COMPOUND AND METHOD FOR THE TREATMENT AND DIAGNOSIS OF NEURODEGENERATIVE CONDITIONS

20230416299 ยท 2023-12-28

    Inventors

    Cpc classification

    International classification

    Abstract

    Pharmaceutical compositions comprising cholestenoic acids and deuterated derivatives thereof, methods of treatment or prevention of neurodegenerative conditions, as well as diagnostic methods and novel biomarkers form aspects of the invention.

    Claims

    1. A method of treatment or prevention of neurodegenerative conditions, which method comprises administering to an individual a pharmaceutical or veterinary composition containing a cholestenoic acid compound of general formula (I) ##STR00007## or a pharmaceutically acceptable salt thereof, wherein R1-R4 are each independently selected from H and deuterium, and at least one of R1-R4 is deuterium, wherein there is a reduction in metabolism of the cholestenoic acid compound to neurotoxic metabolites compared with that of its non-deuterated parent compound.

    2. The method of claim 1, wherein R1 is deuterium and R2, R3 and R4 are hydrogen.

    3. The method of claim 1, wherein R2 is deuterium and R1, R3, R4 are hydrogen.

    4. The method of claim 1, wherein R1 and R2 are deuterium and R3 and R4 are hydrogen.

    5. The method of claim 1, wherein R3 and R4 are deuterium and R1 and R2 are hydrogen.

    6. The method of claim 1, wherein R1, R2, R3 and R4 are deuterium.

    7. The method of claim 1, wherein the cholestenoic acid is a deuterated 3,7-dihydroxycholest-5-en-26-oic acid.

    8. The method of claim 7, wherein the cholestenoic acid is 3,7-dideutero, 3,7-dihyroxycholest-5-en-26-oic acid or a pharmaceutically acceptable salt thereof.

    9. The method of claim 1, wherein the compound is an inhibitor of an epimerase that converts 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) to 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA).

    10. The method of claim 1, wherein the neurodegenerative condition is selected from the group consisting of a systemic atrophy, a muscular atrophy, an atrophy of the central nervous system or a combination thereof and in particular amyotrophic lateral sclerosis (ALS), primary lateral sclerosis (PLS), progressive muscular atrophy (PMA), progressive bulbar palsy (PBP), pseudobulbar palsy (BP), spinal muscular atrophy (SMA), hereditary spastic paresis (HSP), or cerebrotendinous xanthomatosis (CTX).

    11. The method of claim 10, wherein the neurodegenerative condition is selected from amyotrophic lateral sclerosis (ALS).

    Description

    BRIEF DESCRIPTION OF THE FIGURES

    [0058] An embodiment of the invention will now be described by way of example only with reference to the accompanying figures and Tables in which:

    [0059] FIG. 1: shows a schematic of the biosynthesis of cholestenoic acids in brain and levels of cholestenoic acids in the circulation. Panel A shows the suggested metabolic pathway for the biosynthesis of 3-hydroxycholest-5-en-26-oic (3-HCA), 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA), 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA) and 7-hydroxy-3-oxocholest-4-en-26-oic (7H,3O-CA) acids. The pathway may start with cholesterol (C) which is synthesised in brain or 26-hydroxycholesterol (26-HC) which may be formed from cholesterol in brain or imported from the circulation. With the exception of the epimerase, each enzyme is known to be expressed in the brain. Enzyme defects in CTX and SPG5 are depicted by solid bars across arrows. Metabolites toxic towards neurons are shown in as having the exact mass 416.3290 (3-HCA) and 432.3240 (3,7-diHCA) and that which is neuroprotective in shown with mass 432.3240 (3,7-diHCA). Panel B shows the levels of 26-HC, (C) 3-HCA, (D), 3,7-diHCA and (E) 3,7-diHCA (ng/mL, meanSE) in plasma/serum from healthy adults (n=56), children (n=3), adult SPG5 patients (n=9), infants suffering from 07HD (n=3) and CTX patients (n=4, indicated by an arrow). Panel C shows the levels of 3-HCA in plasma/serum from the indicated subjects. Panel D shows the levels of 3,7-diHCA in plasma/serum from the indicated subjects. Panel E shows the levels of 3,7-diHCA in plasma/serum from the indicated subjects. Measurements were made by LC-ESI-MS (see Table 2 below). For sterols the applicants use the abbreviation C for the cholesterol, CO for the cholest-4-en-3-one and CA for the cholesten-26-oic acid structures; while numbers (with Greek letters) indicate the location of hydroxy (H) and oxo (0) groups. In this work the applicants have adopted the sterol nomenclature recommended by the lipid maps consortium, where 26-HC refers to cholest-(25R)-5-en-3,26-diol

    [0060] FIG. 2 shows: an analysis of the nuclear receptor activational capacity of oxysterols and cholestenoic acids. Panel A shows an analysis of luciferase activity in SN4741 neural cells transfected with an Lxr-responsive luciferase reporter construct (Lxre) and Lxr, as indicated, and stimulated for 24 h with 22R-hydroxy cholesterol (22R-HC; 10 m), a known Lxr ligand, or the compounds indicated. In panel B one sees a similar assay performed with cells transfected with an Fxr-responsive luciferase reporter construct (Fxre) and Fxr and stimulated for 24 h with chenodeoxycholic acid (CDCA), a known Fxr ligand, or the compounds indicated. In panel C additional luciferase assays are performed as in panel A with or without the addition of the Lxr antagonist geranylgeranyl pyrophosphate (GGPP, 10 M) along with the cholesterol metabolite indicated (10 M). Other compounds: 24S-hydroxycholesterol (24S-HC); 24R-hydroxycholesterol (24R-HC); 25-hydroxycholesterol (25-HC); 26-hydroxycholesterol (26-HC); 7, 25-dihydroxycholesterol (7, 25-diHC); 7, 25-dihydroxycholest-4-en-3-one (7, 25-diHCO); 7,26-dihydroxy cholesterol (7,26-diHC); 7,26-dihydroxycholest-4-en-3-one (7,26-diHCO); 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA); 7-hydroxy-3-oxocholest-4-en-26-oic acid (7H,3O-CA); 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA); 7-hydroxy-3-oxocholest-4-en-26-oic acid (7H,3O-CA); 3-hydroxy-7-oxocholest-5-en-26-oic acid (3H, 7O-CA); 3-hydroxychol-5-en-24-oic acid (3H-A5-BA); and 3-oxochol-4-en-24-oic acid (30-4-BA) may be relevant.

    [0061] The firefly luciferase activity was normalized to Renilla luciferase activity, and the values are expressed as fold activation over the normalized basal Lxr or Fxr response element-luciferase activity set to 1. Data are meansSE (n=3), *, p<0.05; **, p<0.01 compared with vehicle treatment. Additional analysis was performed on the compounds 5-cholestan-3-ol, 5-cholestan-3-one, cholest-4-en-3-one, cholesta-4,6-dien-3-one, 7-hydroxycholesterol, 7-hydroxycholest-4-en-3-one, 7-hydroxycholesterol, and 7, 12-dihydroxycholest-4-en-3-one which are found at elevated levels in plasma of CTX patients. None of these compounds showed significant activity in the luciferase assay. Panel D shows a time-resolved (TR)-FRET Lxr coactivator assay used to determine the binding affinity of cholestenoic acids towards the Lxr-LBD. Data are meansSEM (n=3) and * represents significant difference (p<0.05) compared with vehicle treatment for cholestenoic acid concentrations of 10 M and higher. Concentration is plotted on a log scale. Panel E illustrates that 3,7-diHCA, 3,7-diHCA and 3-HCA induce significant increases in Abca1, Abcg1, and Srebf1 in SN4741 cells. Data are meansSE (n=3), *, p<0.05; **, p<0.01 compared to vehicle treatment.

    [0062] FIG. 3 shows: Green fluorescent protein (GFP) and abca1 expression in motor neurons in Tg[Isl 1/:GFP] embryos 48 h post fertilization (hpf). Embryos were incubated with 10 M test compound or vehicle added to medium, and the medium was replaced every 12 h with fresh solution (containing test compound or vehicle). Immunocytochemistry was performed using an anti-GFP antibody. In panel 3A one sees dorsal (upper panel) and dorsolateral (lower panel) views of the head/upper back region of embryos treated with vehicle, 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA) or 3-hydroxy-7-oxocholest-5-en-26-oic (3H, 7O-CA) acid. Arrows indicate loci III, IV, V, VII and X. In panel 3B there is quantification of Islet-GFP signal intensity in the different cranial nerves/loci. 245,25-Epoxycholesterol (3-hydroxycholest-5-en-24S,25-epoxide, 24S,25-EC) was used as a positive control. Data are meansSE (n=4), *, p<0.05 compared to each respective locus of vehicle-treated zebrafish.

    [0063] In panel 3C one sees Islet-1 mRNA levels, in panel 3D, and panel 3E Islet-1 one sees protein levels (quantification and representative blot) and in panel 3F obe sees abca1 mRNA levels, after treatment of zebrafish with the compounds indicated. Data are meansSE (n=3), *, p<0.05; **, p<0.01 compared to vehicle-treated zebrafish. Other test compounds: 25-hydroxycholesterol (25-HC); 7-hydroxy-3-oxocholest-4-en-26-oic acid (7H,3O-CA); 3-hydroxychol-5-en-24-oic acid (3H-.sup.5-BA). The cranial nerves (III, IV, V, VII, X) in the zebrafish are evolutionarily homologous to those in humans. Locus III contains the oculomotor neurons, IV contains trochlear neurons, V the trigeminal motor neurons, VII the facial motor neurons and X the cell bodies of the vagus nerve.

    [0064] FIG. 4 shows specific cholestenoic acids increase the number of Islet1+ oculomotor neurons, have a neuronal survival effect, or are toxic in mouse E11.5 brain primary cultures. Panel A shows dose-response curves for the quantification of Islet1+ cells in mouse E11.5 brain primary cultures from wild type (wt) embryos treated with 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA), 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA), 3-hydroxycholest-5-en-26-oic (3-HCA) or 3-hydroxy-7-oxocholest-5-en-26-oic (3H, 7O-OA) acids. Concentration is plotted on a log scale. Data are meansSEM (n=3). * represents significant difference (p<0.05) compared with vehicle treatment for concentrations of 5 M and higher of 3,7-diHCA, 10 M and higher of 3H, 7O-CA, 2 M and higher of 3,7-diHCA, and 2 M and higher of 3-HCA. Panel B shows representative images of Islet-1 and Nkx6.1 stained cell nuclei; 3,7-diHCA and 3H, 7O-CA were at 10 M, 3,7-diHCA and 3-HCA were at 2 M. In panel C there is quantification of Islet1+ cells in mouse E11.5 brain primary cultures from wild type (wt) or Lxr//embryos treated with 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) or 3-hydroxy-7-oxocholest-5-en-26-oic acid (3H, 70-OA). Data are meansSE (n=3), *, p<0.05 compared to vehicle wt group. Panel D shows the effect of the Lxr antagonist geranylgeranyl pyrophosphate (GGPP, 10 M) on the treatments in the wt group. Data are meansSE (n=3), *, p<0.05 compared to -GGPP group as indicated. Panel E shows dose-response curves for the quantification of active caspase 3+ cells in mouse E11.5 brain primary cultures (wt group). Concentration is plotted on a log scale. The symbol ]j indicates very high cell death in the cultures. Data are meansSEM (n=3). * represents significant difference (p<0.05) compared with vehicle treatment for concentrations of 10 M and higher of 3,7-diHCA, 2 M and higher of 3,7-diHCA, and 2 M and higher of 3-HCA. Panel F shows representative images of active caspase 3 and Islet-1 stained cell nuclei. 3,7-diHCA and 3H,3O-CA were at 10 M, 3,7-diHCA and 3-HCA were at 2 M. In panel Gone sees quantification of active caspase 3+ cells in mouse E11.5 brain primary cultures (wt group) treated with 2 or 10 M of the acids as indicated, with or without 10 M GGPP. Data are meansSE (n=3), *, p<0.05 compared to vehicle treatment or compared to -GGPP group as indicated. In 4J 3,7-diHCA reduces the toxic effect of 3,7-diHCA or 3-HCA on Islet1+ cells in mouse E11.5 brain primary cultures (wt group). 10 M 3,7-diHCA reverses the loss of Islet1+ cells in the cultures treated with either 2 M 3,7-diHCA or 3-HCA. Data represent meanSE (n=3), *, p<0.05; **, p<0.01 compared to vehicle treatment, or as indicated. Panel H also shows representative images of Islet-1 stained cell nuclei.

    [0065] FIG. 5 shows: 25-Hydroxycholesterol is increased in Cyp7bl/ mouse brain and plasma, increases the number of Islet+ oculomotor neurons and has a neuronal survival effect in mouse E11.5 brain primary cultures. Panel 5A: levels of 25-hydroxycholesterol (25-HC) in plasma (ng/mL, upper panel) and whole brain (ng/mg, lower panel) from 13 month and 23 month male mice. For plasma analysis n=5 for both wild type (WT) and Cyp7bl knockout (KO) 13 month mice and n=4 for the 23 month mice. For brain analysis n=3 for WT and KO 13 month mice and n=4 for 23 month mice. Panel 5B Quantification of Islet1+ cells in mouse E11.5 brain primary cultures from wild type (wt) or Lxr//embryos treated with 25-HC. Data are meansSE (n=3), *, p<0.05 compared to vehicle wt group. Panel 5C: representative images of Islet-1 stained cell nuclei, and panel 5D the effect of the Lxr antagonist geranylgeranyl pyrophosphate (GGPP, 10 M) on the treatments in the wt group. Panel 5E: quantification of active caspase 3+ cells in mouse E11.5 brain primary cultures (wt group) treated with 10 M of 25-HC with or without 10 M GGPP. Data are meansSE (n=3), *, p<0.05 compared to vehicle treatment or compared to -GGPP group as indicated. Panel 5F: Levels of (upper plot) 7, 12-dihydroxy cholesterol (7, 12-diHC) plus 7, 12-dihydroxycholest-4-en-3-one (7, 12a-diHCO) and (lower plot) cholest-5-ene-3,7, 12, 25-tetrol (7, 12, 25-triHC) plus 7, 12, 25-trihydroxycholest-4-en-3-one (7, 12, 25-triHCO) in whole brain (ng/mg) from 3 month male mice (n=3). In panels 5A and 5F 25-HC, 7, 12-diHC, 7, 12-diHCO, 7, 12, 25-triHC and 7, 12, 25-triHCO were identified and quantified by LC-ESI-MS.sup.n following charge-tagging with GP-hydrazine. In the absence of authentic standards 7, 12, 25-triHC and 7, 12, 25-triHCO were presumptively identified by exact mass, retention time and MS.sup.3 spectra. Data are meansSD, **, p<0.01; ***, p<0.001 compared to WT.

    [0066] FIG. 6 illustrates the competition between the effects of the different cholestenoic acids and 50 demonstration that 3,7-diHCA promotes motor neuron survival in vivo. Panel A shows the results of a time-resolved (TR) FRET Lxr coactivator assay. The effect of 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) (at 10 M) was dose dependency competed by 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) and 3-hydroxycholest-5-en-26-oic (3-HCA). Data are meansSEM (n=3). * represents significant difference (p<0.05) compared with 10 M 3,7-diHCA treatment for concentrations of 2 M and higher of 3,7-diHCA+3,7-diHCA and 5 M and higher of 3,7-diHCA+3-HCA. Concentration is plotted on a log scale. Panels B and C shows how 10 M 3,7-diHCA rescues the toxic effect of 2 M 3,7-diHCA or 3-HCA on Islet+ cells and reduces neuronal cell death induced by these acids as indicated by the number of active caspase 3+ cells in mouse E11.5 brain primary cultures. Data represent meanSEM (n=3), *, p<0.05; **, p<0.01 as indicated. Panel D shows the results of an experiment in which the cholestenoic acids 3,7-diHCA, 3-HCA, or 3-HCA and 3,7-diHCA were injected into the cerebral aqueduct of E11.5 mice in utero and coronal brain sections were analyzed at E13.5 for Islet1+ cell numbers. Data are meansSE (n=3), *, p<0.05; **, p<0.01 as indicated. Panel E shows representative images of coronal sections of E1 3.5 mouse embryo brains (upper images) after in utero injections. Higher magnification images (lower images) of the oculomotor nuclei for each of the treatment groups.

    [0067] FIG. 7: panel 7A shows LC-ESI-MS reconstructed ion chromatograms (RICs5 ppm) of the cholestenoic acids: 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA, peak 1), 7-hydroxy-3-oxocholest-4-en-26-oic/3,7-dihydroxycholest-5-en-26-oic (7H,3O-CA/3,7-diHCA peaks 2) and 3-hydroxycholest-5-en-26-oic (3-HCA, peak 3) acid. The insets show the molecular ions corresponding to the peaks 1, 2a and 3. Sterols were extracted from CSF in ethanol, fractionated according to hydrophobicity by SPE and charge-tagged with the GP reagent to give maximum sensitivity upon LC-ESI-MS analysis. The first step of the charge-tagging process involves oxidation of 3-hydroxy-5-ene groups to 3-oxo-4-enes by cholesterol oxidase from Streptomyces sp. Endogenous 3-oxo-4-ene containing compound are differentiated from those derived from 3-hydroxy-5-enes by repeating the charge tagging reactions, but in the absence of oxidizing enzyme. The charge-tagging process introduces syn and anti conformers (peaks a and b) which may or may not be resolved. Panels 7B, 7C, and 7D present LC-ESI-MS.sup.3 spectra of the three acids in panel 7A. Structures of the ions fragmented by MS.sup.3 ([M].sup.+.fwdarw.[M-79].sup.+.fwdarw.) are shown. Fragmentation nomenclature has been described previously. The retention times and MS.sup.3 spectra are identical to those of authentic standards. Spectra were recorded on the LTQ-Orbitrap. In this work the applicants have adopted the sterol nomenclature recommended by the lipid maps consortium, where 26-hydroxy cholesterol refers to cholest-(25R)-5-en-3,26-diol, and similarly, carboxylic acids which introduce 25R stereochemistry to the side-chain are at C-26.

    [0068] FIG. 8: shows an analysis of the nuclear receptor activational capacity of oxysterols and cholestenoic acids (10 M). Panel A: analysis of luciferase activity in SN4741 cells transfected with an Lxr responsive luciferase reporter construct (Lxre) and Lxr and stimulated for 24 h with 22R-hydroxycholesterol (22R-HC), a known Lxr ligand, or the compounds indicated. Panel B shows dose response curves for the activational capacity of cholestenoic acids on Lxr. Concentration is plotted on a log scale. Similar experiments were performed with cells transfected with Vdre and Vdr (see panel C); and DR5 and Nurr 1 (see panel D). Lithocholic acid (LCA) is a known Vdr ligand. 9-Cis-retinoic acid (9-cis-RA) is a known Rxr ligand. Rxr is the heterodimer partner of Nurrl. Other compounds tested were 24S-hydroxycholesterol (24S-HC); 24R-hydroxycholesterol (24R-HC); 25-hydroxycholesterol (25-HC); 26-hydroxycholesterol (26-HC); 7, 25-dihydroxycholesterol (7, 25-diHC); 7, 25-dihydroxycholest-4-en-3-one (7, 25-diHCO); 7,26-dihydroxy cholesterol (7,26-diHC); 7,26-dihydroxycholest-4-en-3-one (7,26-diHCO); 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA); 7-hydroxy-3-oxocholest-4-en-26-oic acid (7H,3O-CA); 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA); 7-hydroxy-3-50 oxocholest-4-en-26-oic acid (7H,3O-CA); 3-hydroxy-7-oxocholest-5-en-26-oic acid (3H, 7O-CA); 3-hydroxychol-5-en-24-oic acid (3H-A5-BA), 3-oxochol-4-en-24-oic acid (30-4-BA); chenodeoxycholic acid (CDCA). The firefly luciferase activity was normalized to Renilla luciferase activity, and the values are expressed as fold activation over the normalized basal Lxr response element-luciferase activity set to 1. Data are meansSE. (n=3), *, p<0.05; **, p<0.01 compared with vehicle treatment.

    [0069] FIG. 9 shows the effects of cholestenoic acids in combination with other nuclear receptor agonists. Panel A: Lxr activational capacity of 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA), 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA) and 3-hydroxycholest-5-en-26-oic (3-HCA) acids (10 M) in combination with 22R-hydroxy cholesterol (22-HC, 10 M). In panel B Similar experiments performed with Fxr, the three cholestenoic acids and chenodeoxycholic acid (CDCA, 10 M). The experiments in panels A and B were performed otherwise as in FIG. 8. In panel C, quantification of Islet1+ cells in mouse E11.5 brain primary cultures treated with 10 M 3,7-diHCA, 2 M 3,7-diHCA or 2 M 3-HCA in combination with 22-HC. Data are meansSE (n=3), *, p<0.05; **, p<0.01 as indicated.

    [0070] FIG. 10 shows 3,7-diHCA and 3H, 7O-OA require 1xr for expression of motor neuron markers in zebrafish. Panel 1OA: 1xr morpholinos {1xr MO) abolished the effects of the two acids on Islet-1 expression. Control scrambled MO (cMO, upper panel) or 1xr MO (lower panel) injected Tg[Isl1:GFP] embryos were incubated with 10 M test compound or vehicle added to medium, and the medium was replaced every 12 h with fresh solution (containing test compound or vehicle). Immunocytochemistry was performed using an anti-GFP antibody. Dorsal views of the head/upper back region of embryos treated with vehicle, 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA) or 3-hydroxy-7-oxocholest-5-en-26-oic (3H, 70-OA) are shown. Arrows indicate loci III, IV, V, VII and X. Panel 10B: Quantification of Islet-GFP signal intensity in the different cranial nerves/loci. 24S,25-Epoxycholesterol (24S,25-EC) was used as a positive control. Data are meansSE (n=4), *, p<0.05; compared to each respective cMO group.

    [0071] FIG. 11 shows: quantitative analysis of oxysterols and cholestenoic acids in male Cyp7bl/ mouse plasma and brain. Major cholesterol metabolites identified in mouse plasma (WT 13 mo and KO 13 mo, n=5; WT 23 mo and KO 23 mo, n=4), and brain (WT 13 mo and KO 13 mo, n=3; WT 23 mo and KO 23 mo, n=4) by LC-ESI-MSn following SPE and charge-tagging with GP-hydrazine. Samples were from wild type (WT) and Cyp7bl/ (KO) animals at 13 and 23 months (mo). Data are meansSD, *, p<0.05; **, p<0.01; ***, p<0.001 compared to WT. 245,25-Epoxycholesterol (24S,25-EC) isomerizes to 24-oxocholesterol (240-C), undergoes hydrolysis to 24,25-dihydroxycholesterol (cholest-5-ene-3,24,25-triol, 24,25-diHC) and methanolysis to 24-hydroxy-25-methoxy cholesterol (3,24-dihydroxycholest-5-ene-25-methoxide, 24H,25M-C) during derivatisation. Quantification was by stable isotope dilution mass spectrometry using deuterated 24(R/S)-hydroxycholesterol as the internal standard.

    [0072] FIG. 12 shows: quantitative analysis of oxysterols and cholestenoic acids in male Cyp27l/ mouse brain. Major cholesterol metabolites identified in mouse brain (n=3) by LC-ESI-MSn following SPE and charge-tagging with GP-hydrazine. Samples were from wild type (WT) and Cyp27l/ (KO) animals at 3 months. Data are meansSD, *, p<0.05; **, p<0.01; ***, p<0.001 compared to WT In the absence of authentic standards cholest-5-ene-3,7, 12, 25-tetrol (7, 12, 25-triHC) and 7, 12, 25-trihydroxycholest-4-en-3-one (7, 12, 25-triHCO) were presumptively identified by exact mass, retention time and MS3 spectra. Quantification was by stable isotope dilution mass spectrometry using deuterated 24(R/S)-hydroxycholesterol as the internal standard.

    [0073] FIG. 13 illustrates a time course analysis and quantification of the number of Islet1+, active caspase 3+ and Nkx6.1+ cells in mouse E11.5 brain primary cultures. Time course analysis for the quantification of (panel A) Islet1+ cells and (panel B) active caspase 3+ cells in mouse E11.5 brain primary cultures treated with 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA), 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA), 3-hydroxycholest-5-en-26-oic (3-HCA) or 3-hydroxy-7-oxocholest-5-en-26-oic (3H, 7O-CA) acids. The symbol indicates very high cell death in the cultures. Data are meansSEM (n=3). Panel C: Quantification of Nkx6.1+ progenitor cells in the cultures.

    [0074] FIG. 14 illustrates the morphological appearance of cells identified as double-positive Islet1+;ac3+ cells in vivo. The cholestenoic acids 3,7-dihydroxycholest-5-en-26-oic (3,7-diHCA) and 3-hydroxycholest-5-en-26-oic (3-HCA), or 3-HCA were injected into the cerebral aqueduct of E11.5 mice in utero and coronal brain sections were analyzed at E13.5 for double-positive Islet1+;ac3+ cells. A very limited number of oculomotor neurons was undergoing apoptosis in vivo. Representative images of Islet1+/DAPI, Islet1+/ac3+, and DAPI/ac3+ stained cells are shown.

    [0075] FIG. 15 shows: a schematic pathway showing the breakdown of cholesterol in the body and the effect of compounds that are produced; and

    [0076] FIG. 16 shows: specific cholestenoic acids increase the number of Islet 1+ oculomotor neurons, promote neuronal survival, or are toxic in mouse E11.5 brain primary cultures.

    [0077] Table 1 shows: oxysterols and Cholestenoic Acids in Human CSF

    [0078] Oxysterols and cholestenoic acids identified by LC-ESI-MSn in CSF following SPE and charge-tagging with GP-hydrazine. In the absence of authentic standards presumptive identifications based on exact mass, MSn spectra and retention time are given. Samples from 12 individual subjects (bluet) and a pool of fifteen subjects (black %) were analysed.

    [0079] Table 2 shows oxysterols and Cholestenoic Acids in Human Plasma (Serum)

    [0080] Oxysterols and cholestenoic acids identified by LC-ESI-MS.sup.n in plasma (serum) following SPE and charge-tagging with GP-hydrazine. In the absence of authentic standards presumptive identifications based on exact mass, MSn spectra and retention time are given. Control samples from 56 adults (bluet) and 3 children (blackj) were analysed. Data for six adults showing clinically pure HSP SPG5 plus one adult with complicated HSP SPG5 (purple*), three infants suffering from 07HD (gold), and four patients suffering from CTX (brown]}) are given. Clinical data is given in Table 3.

    [0081] Table 3 shows: mutations in SPG5, 07AHD and CTX patients studied.

    [0082] Table 4 shows cholestenoic Acids in Cyp7bl/ and Cyp27l-IMouse Brain and Plasma Cholestenoic acids identified by LC-ESI-MSn following SPE and charge-tagging with GP-hydrazine.

    EXAMPLES

    Materials and Methods

    [0083] Reagents. HPLC grade water and solvents were from Fisher Scientific (UK) or Sigma Aldrich (UK). Authentic sterols, steroids, cholestenoic acids, bile acids and their precursors were from Avanti Polar Lipids (Alabama, USA), Steraloids Inc (Rhode Island, USA), Sigma Aldrich (UK), or from previous studies in our laboratories. Girard P (GP) reagent [1-(carboxymethyl)pyridinium chloride hydrazide] was from TCI Europe (UK) or synthesized in earlier studies, and cholesterol oxidase from Streptomyces sp was from Sigma-Aldrich. Certified Sep-Pak Ci8 200 mg solid phase extraction (SPE) cartridges were from Waters (UK). Leur-lock syringes were from BD Biosiences (UK). Patient Samples. Adult CSF and plasma samples were part of a GlaxoSmithKline study. Plasma/serum from CTX, SPG5 and 07AHD patients were from Barts and the London NHS Trust; St Mary's Hospital, Manchester; Institute of Child Health, London; Conegliano Research Center, Conegliano; Universita degli Studi di Napoli Federico II, Naples; and Kurume University School of Medicine, Kurume, Japan.

    [0084] Animals. Lxr/fi/ mouse cell cultures were from the colony at the Department of Biosciences and Nutrition at Novum, Karolinska Institutet. Male and female wild-type and Lxr/fi/ mice were generated as previously described (Alberti et al. J. Clin. Invest 2001: 107(5), 565-73). Mice were back crossed onto a C57BL/6 background for 10 generations. Male Cyp7bl/ mouse brain and plasma were from animals generated at the University of Edinburgh. Male mice homozygous for targeted disruption of the Cyp7bl gene congenic on the C57BL/6 genetic background (>15 generations backcrossed to C57BL/6) and wild-type littermate controls were generated from Cyp7bl-I+ crosses. Male Cyp27l/ mouse tissue and plasma was purchased from The Jackson Laboratory (ME, USA) strain B6.129-Cyp27ltmlElt/J. The Cyp27l/ colony was backcrossed to C57BL/6J inbred mice for approximately 12 generations by the donating investigator prior to sending to The Jackson Laboratory Repository. Upon arrival, mice were bred to C57BL/6J inbred mice for at least one generation to establish the colony. Wild type animals from the colony were used as controls.

    [0085] Extraction of Sterols. Sterols were extracted from CSF, plasma or mouse brain into ethanol and fractionated by reversed phase SPE to give a cholestenoic acid and oxysterol rich fraction devoid of cholesterol.

    [0086] Charge Tagging of Sterols. The sterols were charge-tagged with the GP-hydrazine to enhance their response when analysed by LC-ESI-MS and tandem mass spectrometry (MS.sup.n).

    [0087] LC-ESI-MS on the LTQ-Orbitrap LC-ESI-MS and LC-ESI-MSn was performed using an Ultimate 3000 HPLC system (Dionex, Surrey, UK) linked to the ESI source of a LTQ-Orbitrap XL or LTQ-Orbitrap Velos (Thermo Fisher, San Jose, CA) mass spectrometer. Luciferase Reporter Assay. The ability of oxysterols and their acidic metabolites to activate several nuclear receptors i.e. Lxr and , Fxr, Vdr, Nurrl was tested in luciferase assays. Transient transfection studies were performed in the mouse neuronal cell line SN4741. This cell line was selected as the oxysterols and acidic metabolites tested were initially identified in CSF. Cells were plated in 24-well plates (5105 cells/well) 24 hr before transfection and transfected with 1 g of plasmid DNA/well complexed with 2 L of Lipofectamine 2000 (Invitrogen). Cells were transfected with 400 ng of a Lxr-, Fxr-, Vdr- or Nurrlresponsive luciferase reporter construct, and 200 ng of Lxr, Lxr, Fxr, Vdr or Nurrl. A reporter gene expressing the Renilla luciferase (pRL-TK, Promega) was co-transfected in all experiments as an internal control for normalization of transfection efficiency. After a 12 h incubation, the lipid/DNA mix was replaced with fresh 2.5% serum medium containing vehicle or appropriate ligand (10 M), as specified in each experiment. The ability of cholestenoic acids to activate Lxr was confirmed in experiments with or without the Lxr inhibitor GGPP (10 M) also added to the medium. Luciferase activities were assayed 24 h later using the Dual-Luciferase Reporter Assay System (Promega), following the manufacturer's protocol.

    [0088] Lxr Ligand Binding Assay. For Lxr ligand binding activity measurement, the applicants used the LANTHASCREEN TR-FRET Lxr Coactivator Assay (Invitrogen). The assay uses a terbium (Tb)-labeled anti-GST antibody, a fluorescein-labeled coactivator peptide and the Lxr-LBD tagged with glutathione-S-transferase (GST). Binding of the agonist/ligand to Lxr-LBD causes a conformational change that result in an increase in the affinity of the Lxr for the coactivator peptide. The close proximity of the fluorescently labeled coactivator peptide to the Tb-labeled antibody causes an increase in the TR-FRET signal intensity. The TR-FRET ratio of 520/495 was calculated using a Victor multi label reader with an excitation wavelength of 340 nm and emission wavelengths of 520 nm and 495 nm. The activational capacity of potential ligands was tested in a 382-well polypropylene plate, following the manufacturer's protocol.

    [0089] Quantitative PCR. Total RNA was extracted from SN4741 cells and zebrafish treated with the compounds of interest using the RNeasy Mini Kit (Qiagen), 1 g was treated with RQ1 RNase-free DNase (Promega) and reverse transcribed using Superscript II Reverse Transcriptase (Invitrogen) and random primers (Invitrogen) (RT+ reaction). Parallel reactions without reverse transcriptase enzyme were done as a control (RT reaction), and Sybergreen real-time quantitative PCR assays were performed. Expression levels were obtained by normalization with the value of the housekeeping gene encoding actin obtained for every sample in parallel assays.

    [0090] Primary Brain Cultures. Brains from E11.5 mice were manually dissected, plated on poly-D-lysine (150,000 cells/cm2) and grown in serum-free N2 media consisting of 1:1 mixture of F12 and DMEM with 10 ng/mL insulin, 100 g/mL apo-transferrin, 100 M putrescine, 20 nM progesterone, 30 nM selenium, 6 mg/mL glucose, and 1 mg/mL BSA. Cells were treated for 3 days in vitro (DIV) with the compounds of interest, fixed with 4% PFA and processed for staining using appropriate antibodies.

    [0091] For BrdU analysis, cells were treated with BrdU one hour after plating and media was replaced with fresh medium after 16 h. After a further 2 days in culture, cells were treated for 30 min with 2N HCl and then immunocytochemistry was performed to evaluate the number of double BrdU+;Islet1+ cells (a measure of motor neuron neurogenesis). Hoechst staining was performed by permeabilizing cells with a 0.3% Triton-X 100/PBS solution for 5 min followed by incubation with Hoechst 33258 (Sigma) for 10 min.

    [0092] Antibodies and Detection Procedures. Cells were fixed in 4% PFA, washed in PBS and blocked in 5% normal goat serum/PBS for 1 h at room temperature. Primary antibodies were diluted in PBS (pH 7.4), 0.3% Triton X-100, 1% BSA and incubations were carried out overnight at +4 C. or at room temperature for 2 h. The antibodies used were anti-: BrdU (1:400; Abeam), Islet-1 (1:100; Developmental Studies Hybridoma Bank), cleaved caspase-3 (Asp175) (1:100; Cell Signaling Technology), tyrosine hydroxylase (TH;1:1000; Pel-Freeze) GABA (1:1,000; Sigma), Brn3a (1:250; Millipore), Nkx6.1 (1:200; Novus Biologicals), choline acetyltransferase (ChAT; 1:500; Millipore) and appropriate secondary antibodies (Jackson ImmunoResearch or Alexa). Cells positive for the corresponding marker were counted directly at the microscope at a magnification of 20 x. Cells were counted in every well, in eight consecutive fields (going from one side of the well to the other, passing through the center), in three different wells per experiment and in three different experiments per condition. Random pictures of the wells were taken for every condition to document the result, and representative pictures were subsequently selected to represent the quantitative data. Photos were acquired with a Zeiss Axioplan microscope and a Hamamatsu camera C4742-95 using the Openlab software.

    [0093] Animals for in-utero injections and tissue preparation. Female wild-type CD-1 mice (25-35 g; Charles River Breeding Laboratories) were housed, bred, and treated according to the guidelines of the European Communities Council (directive 86/609/EEC) and the Society for Neuroscience (www.sfr.org), and all experiments were approved by the local ethical committee. Ethical approval for CD-I mice experimentation was granted by Stockholm Norra Djurforsoksetisks Namnd number N1 54/06, N273/11 and N370/09. For embryo analyses, wild type CD-I mice were mated overnight, and noon of the day the plug was considered E0.5. Embryos were dissected out of the uterine horns in ice-cold PBS, fixed in 4% paraformaldehyde (PFA) for 4 h to overnight, cryoprotected in 15-30% sucrose, frozen in Tissue-Tek Optimum Cutting Temperature (OCT) compound (Sakura Fine-Tek) on dry ice, and stored at 80 C. until use. Serial coronal 14-.Math. sections of the brain were obtained on a cryostat.

    [0094] Immunohistochemical analysis of sections. Ten sets of 14 .Math. serial coronal sections were cut on a cryostat. No. 1 and 6 sets were subjected to immunohistochemistry. Sections were pre-incubated for 1 h in blocking solution followed by incubation at 4 C. overnight with following primary antibodies: anti-TH (1:750, Pel-Freeze), anti-Islet-1 (1:100; Developmental Studies Hybridoma Bank), anti-cleaved caspase-3 (Aspl175) (1:100; Cell Signaling Technology). After washing, slides were incubated for 1-2 h at room temperature with the appropriate fluorophore-conjugated (Cy2-, Cy3- and Cy5-, 1:300, Jackson Laboratories; Alexa488-, 555-, and 647-, 1:1000, Invitrogen) secondary antibodies. Confocal pictures were taken with a Zeiss LSM5 Exciter or LSM700 microscope.

    [0095] In utero intraventricular injections. E11.5 pregnant females were deeply anesthetized using Isofluorane (ISOFLO, Abbott Labs) and the uterine horns were accessed through an abdominal incision. 1 L of the different cholestenoic acids studied (5 mM) or vehicle solution (isopropanol, 50% v/v) was injected into the cerebral aqueduct. The uterine horns were replaced into the abdominal cavity, which was then closed with sutures. Embryos were analyzed 48 h later.

    [0096] Zebrafish Strain and Mainrenance Zebrafish were raised on a 14/10 h day/night cycle and were kept at 28.5 C. Islet-1:GFP transgenic embryos were obtained via natural spawning and staged in hours or days post fertilization (hpf and dpf) according to Kimmel et al). Embryos older than 24 hpf were treated with 0.03% phenylthiourea (PTU) to inhibit pigmentation. MO injections were performed using splice site specific zebrafish 1xr MO. MO injected embryos were immediately dechorionated and transferred to a 96 well plate and exposed to dimethyl sulfoxide (DMSO) treated or ligand treated medium.

    [0097] Compound Exposure. Islet-1:GFP embryos were collected by natural mating and immediately (at 1 cell stage) dechorionated and transferred to a 96 well plate. Each of the compounds tested were obtained as 10 mM stock and diluted in embryo medium to a final concentration of 10 M, and 200 L was added to each well. DMSO or propan-2-ol treated embryo medium was taken as control. Ligand solutions were replaced every 12 h with fresh ligand solution prepared in PTU treated embryo medium. Embryos were collected at 48 hpf, fixed for 4 h at room temperature with 4% paraformaldehyde and then washed and kept in PBST. Immunocytochemistry was performed using an anti-GFP antibody and fluorescence was viewed and photographed using a Zeiss Axioplan compound microscope and a Zeiss Axiocam digital camera.

    SYNTHESIS EXAMPLES

    [0098] ##STR00002##

    ##STR00003##

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    Evaluation of Metabolic Stability

    [0099] The metabolic stability of the deuterated compounds can be compared to that of unlabelled compounds by in vitro incubation (i) with the enzyme HSD3B7 to assess the propensity for oxidation at C-3, (ii) with the enzyme HSD11B1, a putative 7-hydroxy epimerase, and (iii) with peroxisome preparation to asses the propensity for side-chain shortening; followed by mass spectrometry analysis to determine the rate of loss of substrate and the rate of formation products. Similar experiments can be performed with primary cultures of mouse and h an hepatocytes, and of mouse neurons, glial and Schwann cells.

    [0100] To asses in vivo metabolism in brain, mice can be injected with both deuterated compounds and also with analogues, .sup.13C labelled compounds. The presence of both substrates and products can be measured in cerebrospinal fluid and brain tissue, and in both the carotid artery and jugular vein, by mass spectrometry providing a measure of the relative rate of metabolism.

    [0101] As shown in FIG. 16. (A) Quantification of Islet1+ cells in mouse E11.5 brain primary cultures from wild type (wt) or Lxr// embryos treated with 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) or 3-hydroxy-7-oxocholest-5-en-26-oic acid (3H, 7O-CA). Data are meansSE (n=3), *, p<0.05 compared to vehicle wt group. (B) Representative images of Islet-1 stained cell nuclei, and (C) the effect of the Lxr antagonist geranylgeranyl pyrophosphate (GGPP, 10 M) on the treatments in the wt group. (D) Quantification of active caspase 3+ cells in mouse E11.5 brain primary cultures (wt group) treated with 2 or 10 M of the acids as indicated, with or without 10 M GGPP. Data are meansSE (n=3), *, p<0.05 compared to vehicle treatment or compared to -GGPP group as indicated. (E,F) 10 M 3,7-diHCA rescues the toxic effect of 2 M 3,7-diHCA or 3-HCA on Islet1+ cells (E) and reduces neuronal cell death induced by these acids as indicated by the number of active caspase 3+ cells (F) in mouse E11.5 brain primary cultures (wt group). Data represent meanSE (n=3), *, p 0.05; **, p<0.01 as indicated.

    Statistical Analysis

    [0102] Statistical analysis was performed by Student's t-test and Mann-Whitney test using Prism4 (Graphpad Software, La Jolla, CA; www.graphpad.com). p<0.05 was considered a statistically significant difference (*), p<0.01 (**). Data represent meanSE.

    A DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

    [0103] As discussed previously, cholesterol metabolites have the capacity to activate Lxrs but the applicants set out to identify what these metabolites are and how they act in plasma and cerebrospinal fluid (CSF) of patients with human diseases associated with motor dysfunction, cerebrotendinous xanthomatosis (CTX) and hereditary spastic paresis (HSP) type 5 (SPG5) and patients with oxysterol 7-hydoxylase deficiency (07HD). These diseases result from mutations in the cytochrome P450 (CYP27A1, CYP7B1 and CYP7B1) genes, respectively. The enzymes coded by these genes are responsible for (25R),26-hydroxylation of cholesterol and 7-hydroxylation of oxysterols, respectively, reactions that generate further oxysterols and ultimately cholestenoic acids (FIG. 1). It has been found that specific cholestenoic acids with a 3-hydroxy-5-ene, but not a 3-oxo-4-ene, structure activate Lxr and Lxr in neuronal cells, increase expression of Islet-1, a transcription factor required for the development of motor neurons, and promote the survival of Islet1+ oculomotor neurons. Moreover these effects were abolished by knockdown or knock-out of the Lxr receptors in zebrafish or in rodent models. In addition, patients with CTX and SPG5, diseases characterized by ataxia, pyramidal signs, motor dysfunction and spastic paraplegia, are unable to synthesize normal amounts of the Lxr ligand 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA), a cholestenoic acid that the applicants found promotes neuronal survival. Additionally, SPG5 patients exhibit a build-up of 3-hydroxycholest-5-en-26-oic acid (3-HCA), an Lxr ligand that is toxic to mouse motor neurons in vitro and to zebrafish in vivo. These results indicate that specific Lxr ligands regulate the balance between motor neuron survival and death. These findings have important implications for neurological diseases leading to motor dysfunction such as CTX and SPG5, since Lxr ligands, as well as inhibitors of specific biosynthetic enzymes in the cholestenoic acid biosynthetic/metabolic pathway, may be useful pharmaceuticals for the treatment of motor neuron disorders.

    [0104] Cholestenoic acids are abundant in human plasma and human CSF (cerebral spinal fluid) also contains cholestenoic acids. Surprisingly, in CSF the levels of cholestenoic acids were higher than those of oxysterols. The exact identity of 16 oxysterols and downstream metabolites, including cholestenoic acids in human CSF are shown in Table 1. The most abundant of these metabolites were 7-hydroxy-3-oxocholest-4-en-26-oic acid (7H,3O-CA), 3-hydroxycholest-5-en-26-oic acid (3-HCA) and newly identified in CSF 3,7-diHCA and 3,7-dihydroxycholest-5-en-26-oic acid (3,7-diHCA) (19.48-0.25 ng/mL, FIG. 7). Precursors of these acids, including 26-hydroxycholesterol (cholest-(25R)-5-ene-3,26-diol, 26-HC) and newly identified 7,26-dihydroxycholesterol (cholest-5-ene-3,7,26-triol, 7,26-diHC) and 7,26-dihydroxycholest-4-en-3-one (7,26-diHCO), were also found, but at lower levels (0.15-0.02 ng/mL). These results identify four novel oxysterols metabolites in human CSF (FIG. 1) which are downstream of 26-HC. 26-HC is metabolized via 7,26-diHC and 7,26-diHCO or via 3-HCA and 3,7-diHCA to 7H,3O-CA. While 26-HC can cross the blood brain barrier (BBB) and enter brain from the circulation, 7H,3O-CA traverses the BBB and is exported from brain. The applicants went on to measure the level of cholestenoic acids and oxysterols in human plasma to examine the likelihood that cholestenoic acids enter or exit the CSF from or to the circulation (Table 2). The CSF to plasma ratio for 7H,3O-CA is >1:6 while for 26-HC it is <1:130. These ratios are consistent with the concept that while 26-HC in CSF is likely, at least in-part, to be derived by diffusion from blood, this is much less likely to be the situation for 7H,3O-CA and other acids where the concentration gradient is far less steep. Very low levels of 24S-hydroxycholesterol (cholest-5-ene-3,245-diol, 24S-HC), 25-hydroxycholesterol (cholest-5-ene-3,25-diol, 25-HC), and newly identified 7, 25-dihydroxycholesterol (cholest-5-ene-3,7, 25-triol, 7, 25-diHC) and 7a 25-dihydroxycholest-4-en-3-one (7, 25-diHCO) were also found in CSF (0.08-0.01 ng/mL).

    [0105] Low levels of 26-HC have been found in human and mouse brain and in human CSF conversely, 7H,3O-CA, a metabolic product of 26-HC, is exported from brain to blood in human. The CSF to plasma ratios for 7H,3O-CA and 26-HC has been found to be >1:6 and <1:130, respectively. These ratios are consistent with the hypothesis that while 26-HC is imported into the CNS, 7H,3O-CA, the most abundant sterol metabolite found in CSF, is synthesized in the CNS.

    Reduced Levels of 7-Hydroxylated Cholestenoic Acids in Plasma/Serum of Human Patients with CTX Cerebrotendinous-Xanthomatosis and SPG5 Hereditary Spastic Paraplegia

    [0106] Two human diseases that can present with upper motor neuron signs, CTX and SPG5, result from mutations in CYP27A1 and CYP7B1, respectively, two of the genes encoding enzymes required for extrahepatic synthesis of 7H,3O-CA and its precursor 3,7-diHCA (FIG. 1 panel A). In order to examine the pathogenic role of such mutations the applicants decided to first identify the alterations in oxysterol and cholestenoic acid profiles in plasma from these patients and then examine their biological activities. We found that the plasma of patients with CTX was essentially devoid of 26-HC and the down-stream cholestenoic acids (FIG. 1B1E, Table 2). There were elevated levels of 7-hydroxycholesterol (cholest-5-ene-3,7-diol, 7-HC) plus 7-hydroxycholest-4-en-3-one (7-HCO) and/or 7, 12-dihydroxy cholesterol (cholest-5-ene-3,7, 12-triol, 7, 12a-diHC) plus 7, 12-dihy droxycholest-4-en-3-one (7, 12a-diHCO) (see Table 2). The absence of cholestenoic acids in plasma indicates an inability to biosynthesize C27 acids in extrahepatic steroidogenic tissue of the central nervous system (CNS).

    [0107] The applicants also examined patients with SPG5, a disease resulting from mutations in the CYP7B1 gene encoding the oxy sterol 7-hydroxylase responsible for the extrahepatic 7-hydroxylation of side-chain oxidised sterols. In agreement with this, a 6-9 fold increase in 26-HC was been described in plasma of SPG5 patients. Here the applicants studied six patients showing pure SPG5 and one adult showing complex SPG5. In all cases elevated levels of the CYP7B1 substrates 25-HC, 26-HC and 3-HCA (FIG. 1 panel A), as well as reduced levels of its product 3,7-diHCA were found, compared to control subjects (FIG. 1 panels B & C, Table 2). While 3,7-diHCA in the CNS is normally derived from 26-HC, that found in the circulation can be derived via either the 26-HC (acidic) or the 7-HC (neutral) pathway of bile acid biosynthesis. Thus, in SPG5 patients (mutation of CYP7B1) the liver specific 7-hydroxylase, CYP7l, (neutral pathway) accounts for the residual content of 3,7-diHCA found in the circulation.

    [0108] The applicants were also able to analyse CSF from three patients with SPG5 and two health carriers, heterozygotes, with a single mutation in CYP7B1 (data in Table SI and patient description in Table 3). As observed in plasma, levels of 25-HC, 26-HC and 3-HCA were elevated in the patient CSF while 3,7-diHCA was reduced. This indicates that, for these metabolites, plasma represents a good surrogate for CSF.

    [0109] The applicants also investigated the plasma oxysterol and cholestenoic acid profile of three infants with mutations in CYP7B1 (Table 2) resulting in oxysterol 7-hydroxylase deficiency (07AHD) and neonatal liver disease), as well as SPG5 in adults. The first identification of CYP7B1 mutations were found in a child with severe cholestasis, defining an inborn error of bile acid biosynthesis. As expected by the absence of functional CYP7B 1 in these patients, the applicants found very low plasma levels of 3,7-diHCA and elevated levels of 3-HCA, as described above for SPG5 (FIG. 1 panels C and D, Table 2). These patients also had considerably elevated plasma levels of 245-, 25- and 26-HC and high levels of hepatotoxic 3-hydroxychol-5-en-24-oic acid (3H-.sup.5-BA) compared to SPG5 patients and controls. These findings suggest that additional factors, including increased levels of toxic 3-hydroxy-5-ene acids, may contribute to the progressive liver disease at an early age in these patients. The research shows specific changes in 7-hydroxylated cholestenoic acids in plasma/serum of CTX and SPG5 patients so the applicants thus decided to examine their impact on neural function.

    Cholestenoic Acids and Action as Lxr Ligands

    [0110] In order to gain insights into the mechanism by which alterations in cholesterol metabolism causes neurological disease, the applicants studied whether any of the cholestenoic acids present at high levels in control human CSF and deregulated in CSF or plasma of SPG5 or CTX patients work as Lxr ligands. The applicants thus focused on 3-HCA, 3,7-diHCA its isomer 3,7-diHCA and 7H,3O-CA (FIG. 1 panel A), and tested their capacity to activate Lxr and in a neuronal cell line (SN4741). The applicants previously found that 3-HCA activates Lxr and the applicants now show that 3,7-diHCA, its isomer 3,7-diHCA and the necessary intermediate for the inter-conversion of the isomers, 3-hydroxy-7-oxocholest-5-en-26-oic acid (3H, 7O-CA), have the ability to activate both Lxrs and therefore act as Lxr ligands in neural cells (FIG. 2 panel A and FIG. 8 panel A). In addition, the applicants confirmed in our system the capacity of 24S-HC and 25-HC to activate Lxr and the applicants observed that 26-HC had no a significant effect. The applicants also tested the activational capacity of 7H,3O-CA and its 7-isomer (7-hydroxy-3-oxocholest-4-en-26-oic acid, 7H,3O-CA), and the precursors 7,26-diHC and 7,26-diHCO, none of which was found to show significant activity (FIG. 2 panel A, FIG. 8 panel A). Moreover, in order to examine if the identified acidic ligands exert their effect by binding to Lxr, the applicants used the Lxr antagonist geranylgeranyl pyrophosphate (GGPP) which blocked their activity, indicating that the acids are indeed Lxr ligands (FIG. 2 panel C). The activity of the known Lxr ligands 22R-hydroxycholesterol (22R-HC) and 25-HC was similarly blocked.

    [0111] In order to confirm that the cholestenoic acids are indeed agonists to Lxr the applicants tested the Lxr activational capacity of either 3,7-diHCA, 3,7-diHCA or 3-HCA in combination with 22R-HC. No additive effect was observed, indicating that the acid molecules work via the same mechanism as 22R-HC (FIG. 9 panel A). To further examine the specificity of the cholestenoic acids described above, farnesoid X receptor (Fxr) luciferase reporter assays were performed (FIG. 2 panel B). Chenodeoxycholic acid (3, 7-dihydroxy-5P-cholan-24-oic acid, CDC A) activated Fxr. Interestingly 3H-.sup.5-BA (a cholesterol metabolite identified in plasma (Table 2)) also activated Fxr, but was less potent than CDCA. However, none of the other compounds tested activated the Fxr luciferase reporter in the neural cells (FIG. 2 panel B), or modulated the activity of CDCA in neural cells (FIG. 9 panel B). Thus, the cholestenoic acids do not exert their effect via modulating the activity of the Fxr nuclear receptor or its ligands. Similarly, cholestenoic acids did not activate luciferase reporter assays under the control of a DR5 element (activated by Nur-related factor 1 (Nurrl)/retinoid X receptor (Rxr) heterodimers) while 9-cis-retinoic acid (9-cis-RA) activated this reporter (FIG. 8 panel C). Furthermore, while lithocholic acid (3-hydroxy-5P-cholan-24-oic acid, LCA) activated a vitamin D receptor (Vdr) luciferase reporter, none of the cholestenoic acids tested showed any significant effect on Vdr activation in neural cells (FIG. 8 panel B). Thus, our results indicate that 33-HCA, 3,7-diHCA, 3,7-diHCA, and 3H, 7O-CA are specific Lxr ligands in neural cells.

    Cholestenoic Acids Bind and Activate Lxr

    [0112] In order to show that specific cholestenoic acids directly interact with Lxr the applicants performed a binding and activation fluorescence resonance energy transfer (FRET) assay in which ligand binding to the ligand binding domain (LBD) of Lxr recruits a fluorescent coactivator. The applicants found that 3,7-diHCA induced FRET in a dose dependent manner to a higher degree than the other acids (FIG. 2 panel D). To provide further evidence that cholestenoic acids are Lxr ligands in neural cells, the applicants treated neural cells with the individual acids for 3 h and measured Abca1, Abcg1 and Srebf1 transcript levels. 3,7-diHCA increased transcripts levels to a similar degree as 22R-HC, while 3,7-diHCA and 3-HCA induced transcription, but to a lesser extent (FIG. 2 panel E). These results provide further proof that 3-HCA, 3,7-diHCA and 3,7-diHCA are specific Lxr ligands in neural cells.

    Cholestenoic Acids Increase Expression of Islet-1 Protein in Islet-1 GFP Zebrafish Embryos

    [0113] Having established that cholestenoic acids that are altered in CTX or SPG5 can activate Lxrs in vitro, the applicants next sought to identify their effect in vivo. In particular, the applicants focused on the expression of Islet-1, a transcription factor expressed in all postmitotic motor neurons and required for multiple aspects of motor neuron development, including motor neuron specification, motor column formation, axonal growth and maintenance of spinal motor neuron identity. The applicants used transgenic zebrafish embryos expressing green fluorescent protein (GFP) driven by the Isl1 gene promoter/enhancer sequences (Tg[Isl1/:GFP]) to screen for biologically active compounds in vivo. Previous studies have indicated that Islet-1 protein is required for the formation of zebrafish primary motor neurons and is conserved throughout vertebrate evolution. Treatment of transgenic zebrafish embryos with 3-HCA and 3,7-diHCA, two weak Lxr ligands, as well as CDCA, the most potent Fxr ligand, had a deleterious toxic effect which impaired the survival of the fish and precluded further in vivo analysis. The applicants also found that the Lxr agonists 3,7-diHCA and 3 H, 7O-CA increased Islet-GFP expression (FIG. 3 panels A and B), but had no significant effect on the number of Islet1+ cells in the different cranial nerves examined (III, IV, V, VII, X). These effects were specific as 7H,3O-CA, which is not an Lxr ligand, failed to regulate Islet-GFP expression (FIG. 3 panel B). Interestingly, the increase in Islet-GFP expression, observed in response to the specific acidic compounds, was evident in all cranial nerves studied (FIG. 3 panel B). Moreover the increase in Islet-GFP expression by 3,7-diHCA and 3H, 7O-CA was also accompanied by an increase in the level of Islet-1 mRNA and protein, as assessed by qPCR and western blot (FIG. 3 panel C, panel D and panel E). To further verify our results, the applicants examined whether these cholestenoic acids regulated the in vivo expression of endogenous Lxr target genes such as abca1. Our results show enhanced expression of abca1 by both 3,7-diHCA and 3H, 7O-CA but not 7H-3O-CA (FIG. 3 panel F). Finally, in order to determine whether these effects are actually mediated by Lxrs the applicants performed 1xr morpholino (MO) injections in Islet-GFP transgenic fish. Interestingly, the applicants found that 1xr MO injections abolished the in vivo increase in Islet-GFP levels by 3,7-diHCA and 3H, 7O-CA, compared to control scrambled MO (FIG. 10). Thus, our data show that cholestenoic acids are capable of activating endogenous Lxr target genes in vivo and regulate the in vivo expression of Islet-1 in brain motor neurons via Lxr.

    3,7-diHCA Promotes Rodent Motor Neuron Survival In Vitro, while 30,70-diHCA and 3-HCA are Toxic

    [0114] In order to determine the functional relevance of our findings in mammalian cells, it was examined first whether any of the cholestenoic acids present in human CSF and implicated in motor neuron disease were also capable of regulating Islet-1 expression in mouse primary brain progenitor cultures. The applicants first performed dose response analysis of the cholestenoic acids of interest, using a wide range of concentrations; while, 3,7-diHCA and 3-HCA caused the loss of Islet1+ cells in the cultures, 3,7-diHCA and 3H, 7O-CA increased the number of Islet1+ oculomotor cells in the cultures (FIG. 4 panel A & panel H). The Islet1+ cells co-expressed the transcription factor Nkx6.1 (FIG. 4 panel B) and choline acetyltransferase (ChAT) (data not shown), therefore were true (bonafide) oculomotor neurons. Time course analysis confirmed the stimulatory effect of 3,7-diHCA and 3H, 7O-CA, as well as the toxic effects of 3,7-diHCA and 3-HCA over a range of incubation times (FIG. 13 panel A). Our analysis shows that the peak of motor neuron production occurred after 2 days in culture and leveled thereafter. These results thus confirmed the dual effects of cholestenoic acids in zebrafish, where 3,7-diHCA and 3-HCA caused the death of the fish while 3,7-diHCA and 3H, 7O-CA regulated Islet-1 expression, providing further evidence of the differential effect of cholestenoic acids on Islet 1+ oculomotor neurons. Interestingly, the effects of 3,7-diHCA and 3H, 7O-CA were specific to motor neurons as they did not affect the number of other midbrain neurons such as TH+ dopamine neurons, GABAergic or red nucleus neurons in the cultures (data not shown).

    [0115] Furthermore, neither 3,7-diHCA nor 3-HCA altered the total number of Nkx6.1+ cells in the cultures (FIG. 13 panel C), which shows that the cholestenoic acids studied did not affect the number of Nkx6.1+ progenitor cells, but only mature double positive Islet1+;Nkx6.1+ oculomotor neurons. In order to examine whether the effects of 3,7-diHCA and 3 H, 70-CA were specifically mediated by Lxr receptors in the rodent brain, the applicants performed progenitor brain cultures from Lxr//mice. Remarkably, the effects of the two cholestenoic acids (at their most potent concentration) on Islet1+ neurons were eliminated, confirming that 3,7-diHCA and 3H, 7O-CA regulate the number of Islet1+ cells in the rodent brain through Lxrs (FIG. 4 panel C). Moreover, the effects of these two acids were blocked by the Lxr antagonist GGPP, indicating that the observed effects are mediated by Lxr receptors (FIG. 4 panel D).

    [0116] In order to unequivocally examine whether the effects of 3,7-diHCA and 3H, 7O-CA are indeed specifically mediated by Lxr receptors in the rodent brain, primary ventral midbrain cultures from Lxr//mice were performed. Remarkably, the effects of the two cholestenoic acids on Islet1+ neurons were eliminated, confirming that 3,7-diHCA and 3H, 7O-CA regulate the number of Islet-1+ cells in the rodent brain through Lxrs (FIG. 4 panel A). Interestingly, 26-HC, a precursor of cholestenoic acids in the acidic pathway of bile acid biosynthesis, which had no Lxr activational effect in luciferase assays in neural cells (FIG. 2), was also shown to have no effect on the number of Islet1+ cells (data not shown). Furthermore, the effects of 3,7-diHCA, 3,7-diHCA or 3-HCA on Islet1+ cells, were not altered by the known Lxr ligand 22R-HC (FIG. 9 panel C), which does not show an effect towards Islet1+ cells. These findings are very exciting as the applicants recently reported that brain endogenous Lxr ligands regulate neurogenesis and/or survival in the developing midbrain. However, none of the known endogenous brain Lxr ligands regulated the function of oculomotor neurons. The applicants thus decided to examine the mechanism by which 3,7-diHCA and 3H, 7O-CA increased the number of Islet1+ cells and studied their role in neurogenesis, proliferation and motor neuron survival in the developing brain.

    [0117] Neurogenesis was examined in bromodeoxyuridine (BrdU) pulse-chase experiments, where neuronal progenitors in primary cultures are labeled with a pulse of BrdU at the beginning of the experiment and then are examined for their differentiation into motor neurons, as assessed by the acquisition of Islet-1 expression, a marker for motor neuron fate. Surprisingly, none of the cholestenoic acids studied affected the number of double BrdU+;Islet+ cells, indicating that they do not promote motor neuron neurogenesis. Similarly, none of the cholestenoic acids affected the total number of BrdU+ cells in the cultures, indicating that they do not modulate proliferation. Finally, it was tested whether cholestenoic acids regulate neuronal survival as assessed by active caspase-3 staining to detect the number of cells undergoing apoptosis in the cultures. Interestingly, treatment with 10 M 3,7-diHCA decreased the number of active caspase-3+ cells (FIG. 4 panel E with representative pictures shown in FIG. 4 panel F). In contrast, 3H, 7O-CA did not affect the number of active caspase-3+ cells (FIG. 4 panel E and 4 panel F), indicating that the increase in Islet1+ cells by this molecule is not due to increased survival, but rather neuronal differentiation. Cholestenoic acids that reduced the number of Islet1+ cells were also examined for their capacity to induce cell death in motor neuron cultures. Interestingly, the applicants found that low concentrations of either 3,7-diHCA or 3-HCA increased the number of active caspase-3+ cells (FIG. 4 panel E and 4 panel F) with toxicity being initiated at 1 M. No surviving cells were detected when cultures were treated with concentrations of 3,7-diHCA or 3-HCA higher than 5 M. Time course experiments showed that toxicity was evident after two days of incubation (FIG. 5 panel B).

    [0118] The survival promoting effect of 3,7-diHCA was completely blocked by co-incubation with the Lxr inhibitor GGPP, indicating that the survival effect of this acid is mediated by Lxr (FIG. 4 panel G). On the contrary, the cell death effects of 3,7-diHCA or 3-HCA (at 2 M) were not blocked by GGPP (FIG. 4 panel G), indicating that the survival-promoting effects of 3,7-diHCA, but not the toxic effects of 3,7-diHCA or 3-HCA, were mediated by Lxr.

    [0119] In contrast, 10 M 3H, 7O-CA did not affect the number of active caspase-3+ cells, indicating that the increase in Islet1+ cells is not due to increased survival, but rather neuronal differentiation. Cholestenoic acids that reduced the number of Islet1+ cells were also examined for their capacity to induce cell death in motor neuron cultures. Interestingly, the applicants found that lower concentrations, 2 M, of either 3,7-diHCA or 3-HCA increased the number of active caspase-3+ cells. Moreover, no surviving cells were detected when cultures were treated with 10 M 3,7-diHCA or 3-HCA. The cell death effects of these two acids (at 2 M), unlike the survival-promoting effects of 3,7-diHCA, were not blocked by GGPP, indicating that the survival-promoting effects of 3,7-diHCA, but not the toxic effects of 3,7-diHCA or 3-HCA, are mediated by Lxr. As a final experiment the applicants tested whether 3,7-diHCA could reduce the toxic effect of 3,7-diHCA or 33-HCA. The applicants found that addition of 10 M 3,7-diHCA reversed the loss of Islet1+ cells in the cultures treated with either 2 M 3,7-diHCA or 3-HCA (FIG. 4 panel J). This is an important finding as it offers an avenue for therapeutic intervention.

    [0120] In order to examine whether there is competition between the effects of the cholestenoic acids studied the applicants performed several studies. In a binding and activation FRET assay, when 3,7-diHCA at its most potent concentration, was used together with increasing concentrations of 3,7-diHCA or 3-HCA, the effect of 3,7-diHCA was reduced to that of the latter acids, indicating that there was competition between the various cholestenoic acids for binding to the LBD of Lxr (FIG. 6 panel A). Additionally, when the applicants tested whether 3,7-diHCA could reduce the toxic effect of 3,7-diHCA or 3-HCA, the applicants found that treatment with 10 M 3,7-diHCA reversed the loss of Islet 1+ cells induced by either 2 M 3,7-diHCA or 3-HCA (FIG. 6 panel B). Finally, treatment with 10 M 3,7-diHCA reduced the neuronal cell death (indicated by activated caspase 3) induced by either 2 M 3,7-diHCAor 3-HCA (FIG. 6 panel C). This is an important finding as it reinforces the notion of balance between the survival- and death-inducing effects of cholestenoic acids and offers a new avenue for therapeutic intervention.

    [0121] Thus, combined, our results indicate that cholestenoic acids regulate the number of Islet+ motor neurons by controlling the expression of Islet-1 (3H, 7O-CA), and regulating neuronal survival in a positive (3,7-diHCA) or a negative (3,7-diHCA and 3-HCA) manner.

    Cyp7bl Knockout Mice Exhibit Elevated Levels of 25-HC and do not Suffer from Motor Neuron or Liver Disease

    [0122] In light of the human diseases associated with mutations in the CYP7B1 and 27A1 genes the applicants decided to examine the sterol profiles of Cyp7bl and Cyp27l knockout mice (Cyp7bl/ and Cyp27l/, respectively). As neither Cyp7bl/ nor Cyp27l/ mice suffer from motor neuron dysfunction. The plasma and brain tissue samples from adult male knockout animals were analysed to search for the presence of the survival-promoting acid. LC-ESI-MS spectra of the Cyp7bl/ mouse revealed an absence of 3,7-diHCA, its 7-isomer and also 3 H, 7O-CA both in plasma (n=9) and in whole brain tissue (n=7). An active bile acid biosynthesis pathway was maintained in these animals as indicated by the presence of 7H,3O-CA in plasma (FIG. 9), formed via the neutral pathway of bile acid biosynthesis initiated via Cyp7l catalysed 7-hydroxylation of cholesterol. Elevated levels of Cyp7bl substrates 25-HC, 26-HC and 3-HCA were found in both plasma and brain tissue of the knockout animals, compared to wild-type control animals (FIG. 5 panel 5A & 9). Thus, the analysis of the levels of sterols in plasma of Cyp7bl/ mice show that these mice phenocopy to a large extent SPG5 patients (Table 2). However, the Cyp7bl/ mouse does not show a motor neuron disease phenotype. This is in contrast to the adult male Lxr/animal, so the possibility exists that some other Lxr ligands in mouse may be responsible for providing a pro-survival effect towards motor neurons. Of the Lxr ligands identified in Cyp7bl/ mouse brain 25-HC shows the greatest elevation in abundance in Cyp7bl/ mouse, from undetectable levels in wild type mice to >2 ng/mg in 23 month old male mice. Significantly, this oxysterol is barely detectable in human brain and CSF (Table 1), and its level is not elevated in the CSF of SPG5 patients. Since 25-HC induced a modest increase in the levels of Islet-1 in Islet1-GFP transgenic fish in vivo (FIG. 3 panel B), the applicants investigated whether 25-HC could also promote motor neuron survival. The applicants found that 25-HC, shared with 3,7-diHCA its capacity to increase the number of Islet1+ oculomotor cells in E11.5 mice brain cultures (FIG. 5 panel 5B & 5 panel 5C). Moreover this effect was inhibited by the Lxr antagonist GGPP (FIG. 5 panel 5D), and was blocked in cultures from Lxr//animals (FIG. 5 panel 5B), indicating that the effect of 25-HC on motor neuron cell numbers is mediated by Lxrs. Finally, the applicants examined whether 25-HC was also capable of decreasing the number of apoptotic cells in motor neuron cultures. The applicants found that 25-HC reduced the number of active caspase-3+ cells in a GGPP sensitive manner (FIG. 5 panel 5E), indicating that the survival-promoting effects of 25-HC are specific and mediated by Lxr.

    [0123] The applicants next analysed the oxysterol and cholestenoic acid profile of whole brain tissue 50 of Cyp27l/ adult male mice and found an absence of 3,7-diHCA, 3H, 7O-CA and also 25-HC. The levels of 7-HC and 7-HCO; 7, 12a-diHC and 7, 12a-diHCO; 7, 25-diHC and 7, 25-diHCO; and also of a trihydroxycholesterol and a trihydroxycholest-4-en-3-one, probably 7, 12, 25-trihydroxycholesterol (cholest-5-ene-3,7, 12, 25-tetrol, 7, 12, 25-triHC) and 7, 12, 25-trihydroxycholest-4-en-3-one (7, 12, 25-triHCO), were elevated in the brain of the knockout mouse (FIG. 5 panel 5F & FIG. 12).

    3,7-diHCA Promotes Rodent Motor Neuron Survival In Vivo

    [0124] In order to demonstrate motor neuron survival in vivo in a mammalian system, 3,7-diHCA was injected into the cerebral aqueduct of E11.5 mice in utero and brain sections were analyzed at E13.5 for Islet1-, TH- and ac3-positive cells. The applicants observed an increase in the number of Islet+ oculomotor neurons but not of TH+ neurons (FIG. 6 panel D and 6 panel E). Upon injection of 3-HCA the number of Islet+ oculomotor neurons was reduced, however, this effect was eliminated by co-injection of 3,7-diHCA. This data provide further support to the specificity of the neuronal survival and toxic effects of these cholestenoic acids on Islet1+, but not TH+, neurons reported in primary culture experiments above.

    [0125] In addition the applicants occasionally observed double-positive Islet1+;ac3+ cells (FIG. 14), which suggested that there was a very limited number of oculomotor neurons undergoing apoptosis in vivo. This has not to our knowledge been shown before, therefore proving the strength of our injection technique.

    [0126] Thus, our results show that specific cholestenoic acids have similar positive or negative effects on Islet1+ motor neurons both in vivo and in vitro.

    [0127] The studies reported here show that cholestenoic acids are not mere intermediate metabolites of bile acid biosynthesis, but are rather a diverse family of bioactive compounds, capable of regulating nuclear receptor function. As such, cholestenoic acids were found to specifically activate Lxr and elicit an exquisite array of functions ranging from the regulation of Islet-1 expression, to the positive and negative regulation of motor neuron survival both in vitro and in vivo. Moreover, our study identifies cholestenoic acids in human CSF to be deregulated in plasma of patients with monogenetic motor neuron dysfunction, specifically CTX and SPG5 patients. Importantly, an absence of neuroprotective cholestenoic acids was found in CTX, while a combination of decreased neuroprotective and increased toxic cholestenoic acids was detected in SPG5. These results thus identify cholestenoic acids as key regulators of motor neuron function in development and disease.

    [0128] Cholesterol is present at high levels in the CNS of vertebrates and is metabolized in brain predominantly to 24S-HC which accounts for about two thirds of brain cholesterol metabolism. Low levels of 26-HC have been found in human and mouse brain and in human CSF where it may be imported from the blood. Conversely, 7H,3O-CA, a metabolic product of 26-HC, is exported from brain to blood in human. Four intermediates in the biosynthesis of 7H,3O-CA from 26-HC via CYP27A1 and CYP7B1 to be present in CSF i.e. 3,7-diHCA, 3-HCA, 7,26-diHCO and 7,26-diHC (FIG. 1 panel A) have been found by the applicants. While 3-HCA and 7,26-diHC were previously found in human neural tissue, 3,7-diHCA and 7,26-diHCO have not been previously found in neural tissue or CSF. Importantly, the identification of these intermediates in the biosynthesis of 7H,3O-CA lends further support to the hypothesis that 7H,3O-CA is biosynthesised in the human brain. This pathway is also conserved in rodents where 26-HC is the precursor for the synthesis of 3-HCA in fetal neurons and of 3,7-diHCA and 7H,3O-CA in fetal astrocytes (FIG. 1 panel A).

    [0129] In human CSF and plasma the applicants also identified 3,7-diHCA but not its 3-oxo-4-ene metabolite. This result is in agreement with the earlier finding that hydroxysteroid dehydrogenase (HSD) 3B7, which acts on 7-hydroxylated C27 sterols converting them to their 3-oxo-4-ene analogs, is expressed in brain but does not metabolize 7-hydroxylated sterols. The absence of such a metabolic sink may thus account for the comparatively high level of 3,7-diHCA in human CSF (Table 1). Importantly, here the applicants show that 3,7-diHCA and 3H, 7O-CA, the necessary intermediate in the epimerization reaction from the 3,7-isomer, also work as Lxr ligands (FIG. 2 panel A and FIG. 7 panel A).

    [0130] Classical studies by Lehmann et al and Janowski et al defined the general structural requirements of steroidal Lxr ligands to be a 3-hydroxy-5-ene function in the ring system and a hydroxy, oxo or epoxide function on the C-17 side-chain. The side-chain functions have more recently been extended to include a carboxylic acid group, a functional group which is also present in the synthetic non-steroidal Lxr ligand GW3965. In the current study, the applicants confirm the Lxr-activational capacity of cholestenoic acids with a 3-hydroxy-5-ene structure in neural cells, and show that despite the introduction of either a 7- or 7-hydroxy or a 7-oxo group, Lxr activity is maintained. On the contrary, the 3-oxo-4-ene equivalents of these acids are not Lxr ligands. Thus, 3-HCA, 3,7-diHCA, its 7-isomer, and the necessary 7-oxo intermediate in the epimerization reaction, are all Lxr ligands. Moreover, none of these acids were found to activate Fxr, Vdr or Nurrl in neural cells, thereby confirming the specificity of their effect on Lxr.

    [0131] A number of studies in recent years have linked Lxr to neuronal degeneration. These studies have utilized Lxr/ and Lxr//mice. Indeed, both Lxr isoforms are expressed in brain and the knock-out mice show progressive accumulation of lipids in brain, abnormal blood brain barrier, increased reactive microglia, astrogliosis and degeneration of adult spinal cord motor neurons. Interestingly, a decrease in the number of oculomotor neurons was also detected during development in the Lxr//mice at E11.5. However, it was not known whether Lxr ligands regulate the development of motor neurons in vivo. Moreover, the identity of endogenous brain Lxr ligands that regulate motor neuron function was unknown. Here the applicants used zebrafish to study the in vivo function of acid Lxr ligands newly identified in human CSF, 3,7-diHCA and 3,7-diHCA, and the 7-oxo intermediate in their epimerization, on Islet1+ cranial motor neurons. While metabolites that did not activate Lxr, such as 7H,3O-CA, did not regulate the expression of Islet-1, the applicants found that two Lxr ligands 3,7-diHCA and 3H, 7O-CA enhance the expression of Islet-1 transcript and protein in zebrafish embryos (FIG. 3), effects that were abolished by injection of 1xr MO (FIG. 10). These effects were confirmed in rodent primary oculomotor neuron cultures, which showed that only 3,7-diHCA and 3H, 7O-CA acids increased the number of Islet1+ neurons (FIG. 4 panel A, panel B, panel C and panel D). Importantly their activity was specific to and mediated by Lxr, as their biological activities were eliminated in cultures from Lxr//mice. The effect of 3,7-diHCA on wild type cultures was accompanied by a decrease in the number of active caspase 3+ cells (FIG. 4 panel E), but no change in neurogenesis or proliferation was detected, indicating that the mechanism by which it increased the number of motor neurons was by promoting neuronal survival. In vivo experiments performed on embryonic brain in utero confirmed this neuroprotective effect of 3,7-diHCA on oculomotor neurons (FIG. 5 panels 5A, 5B, 5C and 5D). In vivo experiments performed on embryonic brain in utero confirmed this neuroprotective effect of 3,7-diHCA on oculomotor neurons (FIG. 5 panels 5A, 5B, 5C and 5D). In contrast, 3H, 7O-CA had no effect on cell death, neurogenesis or survival, but increased the expression of Islet-1, suggesting that it promoted the maturation of precursor cells into Islet1+ cells. Analysis of the function of 3,7-diHCA revealed a toxic effect which was manifested by an increase in the number of caspase3+ cells at low doses of this Lxr ligand (FIG. 4 panel E). Thus, our results indicate that only some of the cholestenoic acids capable of activating Lxr regulate motor neuron development. Our findings indicate that cholestenoic acids regulate motor neuron number by 50 distinct mechanisms involving the regulation of differentiation and survival. Moreover, the applicants found that the regulation of motor neuron survival could be either positive, as shown by the neuroprotective effect of 3,7-diHCA, or negative, as shown by the toxic effect 3,7-diHCA and 3-HCA (FIGS. 4 and 5). These results were quite unexpected but correlated very well with the cholestenoic acid profiles in patients with CTX and SPG5, two human diseases characterized by mutations in CYP27A1 and 7B1 genes, respectively, and which may present with signs of upper motor neuron loss or dysfunction. Indeed, the applicants found that 3-HCA one of the Lxr ligands identified to have a toxic effect, was present at higher levels in SPG5 patients in both plasma and CSF (Tables 1 and 2). At the same time, the Lxr ligand found to be neuroprotective, 3,7-diHCA, was present at lower levels in SPG5 and absent in CTX (FIG. 1 panel C). Thus, our results suggest a double hit model for SPG5, in which the loss of motor neurons is contributed by both mechanisms, while in CTX, the predominant mechanism would be by the loss of neuroprotection.

    [0132] The fact that the upper motor neuron phenotype of SPG5 and CTX often presents in the adolescent or adult argues against the Lxr ligands presented here being exclusively essential for motor neuron development. However, the applicants know that deletion of Lxrs results in motor neuron loss (1). Thus, the lack of an early phenotype in human patients with SPG5 or CTX indicates that other endogenous Lxr ligands are present in the brain and contribute to motor neuron development. Indeed the Cyp7bl/ and Cyp27l/ mice, do not suffer from motor neuron disease despite an absence of 3,7-diHCA in brain and plasma (Table 4). This finding suggest that while the developmental function of the cholestenoic acids identified here is redundant with that of other Lxr ligands, the accumulative effect of altered levels of cholestenoic acids over extended periods of time, as in SPG5 and CTX, may play a decisive role in motor neuron disease.

    [0133] To summarize, in this study the applicants identified 3,7-diHCA and 3,7-diHCA as Lxr ligands present in human CSF. Of these, 3,7-diHCA, and the previously identified Lxr ligand, 3-HCA, were found to cause cell death, and the latter was present at high levels in patients with SPG5. Instead, 3,7-diHCA, which was found at low levels in SPG5 and was absent from CTX patients, promoted motor neuron survival, while 3H, 7O-CA regulated Islet-1 expression levels. Thus, our results uncover several novel functions of cholestenoic acids and identify them as Lxr ligands and as key regulators of motor neuron function in development and disease. Moreover, our study reveals that an orchestra of Lxr ligands regulates the development and survival of motor neurons. The results show that some specific cholestenoic acids selectively work on motor neurons, via Lxr, to regulate the balance between survival and death. These findings provide a mechanism for motor neuron dysfunction, for example in CTX and SPG5 and suggest that efforts aimed at restoring the balance between toxic and pro-survival Lxr ligands, such as administration of 3,7-diHCA or, in some cases, 25-HC may thus find a therapeutic application to prevent motor neuron loss and the treatment of motor neuron disease.

    [0134] FIG. 15 shows a schematic pathway showing the breakdown of cholesterol in the body and the effect of compounds that are produced. As can be seen, both neurotoxic and neuroprotective compounds can be produced which may be in different ratios. The invention relates to deuterated compounds and in particular cholestenoic acids which have deuterated groups and the compounds that are deuterated are represented by those of formula (I). Deuterated (also referred to as D or 2H) means that at least one of the atoms in the compound is deuterium in an abundance that is greater than the natural abundance of deuterium (typically approximately 0.015%). Deuterium refers to an isotope of hydrogen wherein the nucleus contains one proton and one neutron.

    [0135] The concentration of deuterium at a designated position may be defined by the deuterium enrichment factor. Deuterium enrichment factor in the context used herein refers to the ratio between the deuterium isotopic abundance and the natural abundance of deuterium, each relative to hydrogen abundance.

    [0136] If a substituent in a compound of this invention is denoted as deuterium, such compound has a deuterium enrichment factor for each designated deuterium atom of: [0137] at least 1000 (15% deuterium incorporation at each designated deuterium atom); [0138] at least 2000 (30% deuterium incorporation at each designated deuterium atom); [0139] at least 3000 (45% deuterium incorporation at each designated deuterium atom); [0140] at least 4000 (60% deuterium incorporation at each designated deuterium atom); [0141] at least 5000 (75% deuterium incorporation at each designated deuterium atom); [0142] at least 6000 (90% deuterium incorporation at each designated deuterium atom); [0143] at least 6466.7 (97% deuterium incorporation at each designated deuterium atom); [0144] at least 6600 (99% deuterium incorporation at each designated deuterium atom); or [0145] at least 6633.3 (99.5% deuterium incorporation at each designated deuterium atom).

    [0146] As stated according to a first aspect of the invention the compounds are of general formula (I) but there may be following variations of the compound or a pharmaceutically acceptable salt thereof, where R1-R4 are each independently selected from H and deuterium; and [0147] at least one of R1-R4 is deuterium.

    [0148] These compounds are shown as compound (II) to (IX):

    ##STR00005## ##STR00006##

    [0149] For the compound of the invention there may be isotopic variation among the constituent atoms of the molecules. Thus the extent of deuteration at each designated position is not necessarily the same. By way of example, when a compound of the present invention contains multiple deuterium atoms, the deuterium enrichment factor for one designated deuterium atom may be 3000 and the deuterium enrichment factor for another designated deuterium atom may be 5000. Such a compound is considered therefore to have a deuterium enrichment factor of 3000.

    [0150] The structural formulae shown herein may or may not indicate whether atoms at certain positions are isotopically enriched with respect to deuterium. Thus in a general embodiment, when a structural formula is silent with respect to whether a particular position is isotopically enriched, it is to be understood that the stable isotopes at that particular position are present at, or close to, natural abundance or alternatively D indicates that the stable isotopes at that particular position are deuterium enriched.

    [0151] The structural formulae shown herein may or may not indicate specific enantiomers for chiral centres where such chiral centres exist. Where a chiral centre exists but enantiomeric specificity is not designated it is understood that both or all chiral enantiomers are encompassed by the formula. As such, compounds of the present invention can exist as either individual enantiomers, or mixtures of the two enantiomers. Accordingly, a compound of the present invention may exist as either a racemic mixture or a scalemic mixture, or as individual respective stereoisomers that are substantially free from another possible stereoisomer. The term substantially free of other stereoisomers as used herein means less than 25% of other stereoisomers, preferably less than 10% of other stereoisomers, more preferably less than 5% of other stereoisomers and most preferably less than 2% of other stereoisomers are present. Methods of obtaining or synthesizing an individual enantiomer for a given compound are known in the art and may be applied as practicable to final compounds or to starting material or intermediates.

    [0152] Compounds of the present invention may be formulated to treat or provide a therapy for a range of motor neurone diseases. Treat or therapy means decrease, suppress, attenuate, diminish, arrest, or stabilize the development or progression of a disease (e.g., a disease or disorder delineated herein), lessen the severity of the disease or improve the symptoms associated with the disease. Additionally, it includes prophylactic use. The treatment or therapy may be on humans or animals.

    [0153] The compound will be formulated to contain deuterated compound in an amount such that, depending on the route of administration and prescribed frequency, the required daily or weekly dosage of deuterated compound is provided. The composition will be formulated to allow for daily administration or so it can be incorporated in a treatment regime. The compounds may be used on their own or formulated in combination with other therapeutic compounds for the treatment of motor neurone disease.

    [0154] Motor Neurone Disease in the context used herein is understood to be a disorder selected from Amyotrophic Lateral Sclerosis (ALS), Primary Lateral Sclerosis (PLS), Progressive Lateral Sclerosis (PLS), Progressive Bulbar Palsy (PBP), pseudobulbar palsy, Spinal Muscular Atrophy (SMA), spinobulbar muscular atrophy, Charcot-Marie-Tooth disease and other degenerative disorders of upper and/or lower spinal motor neurones irrespective of whether they are classified as motor neurone disease in commonly used disease classification systems such as Medical Subject Headings (MeSH) or the International Statistical Classification of Diseases and Related Health Problems (ICD-10). It is also understood that motor neurone diseases may be known by alternative names and/or is subject to different classification in territories other than the United Kingdom (for example Lou Gehrig's disease in the United States).

    [0155] When they are used, the compounds are included in a pharmaceutically acceptable carrier that means a component that is, within the scope of sound medical judgment, suitable for use in contact with the tissues of humans and other mammals without undue toxicity, irritation, allergic response and the like, and are commensurate with a reasonable benefit/risk ratio.

    [0156] Such carriers include pharmaceutically acceptable salts means any non-toxic salt that, upon administration to a recipient, is capable of providing, either directly or indirectly, a compound of this invention. A pharmaceutically acceptable counter-ion is an ionic portion of a salt that is not toxic when released from the salt upon administration to a recipient. Acids commonly employed to form pharmaceutically acceptable salts include inorganic acids such as hydrogen bisulfide, hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid and phosphoric acid, as well as organic acids such as para-toluenesulfonic acid, salicylic acid, tartaric acid, bitartaric acid, ascorbic acid, maleic acid, besylic acid, fumaric acid, gluconic acid, glucuronic acid, formic acid, glutamic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, lactic acid, oxalic acid, para-bromophenylsulfonic acid, carbonic acid, succinic acid, citric acid, benzoic acid and acetic acid, as well as related inorganic and organic acids.

    [0157] A salt of a compound of this invention is formed between an acid and a basic group of the compound, such as an amino functional group, or a base and an acidic group of the compound, such as a carboxyl functional group. Pharmaceutically acceptable salts thus include but are not limited to sulfate, pyrosulfate, bisulfate, sulfite, bisulfite, phosphate, monohydrogenphosphate, dihydrogenphosphate, metaphosphate, pyrophosphate, chloride, bromide, iodide, acetate, propionate, decanoate, caprylate, acrylate, formate, isobutyrate, caprate, heptanoate, propiolate, oxalate, malonate, succinate, suberate, sebacate, fumarate, maleate, butyne-1,4-dioate, hexyne-1,6-dioate, benzoate, chlorobenzoate, methylbenzoate, dinitrobenzoate, hydroxybenzoate, methoxybenzoate, phthalate, terephthalate, sulfonate, xylene sulfonate, phenylacetate, phenylpropionate, phenylbutyrate, citrate, lactate, [beta]-hydroxybutyrate, glycolate, maleate, tartrate, methanesulfonate, propanesulfonate, naphthalene-1-sulfonate, naphthalene-2-sulfonate, mandelate and other salts. Pharmaceutically acceptable acid addition salts include those formed with mineral acids such as hydrochloric acid and hydrobromic acid, and especially those formed with organic acids such as maleic acid. The pharmaceutically acceptable salt may also be a salt of a compound of the present invention having an acidic functional group, such as a carboxylic acid functional group, and a base. Exemplary bases include, but are not limited to, hydroxide of alkali metals including sodium, potassium, and lithium; hydroxides of alkaline earth metals such as calcium and magnesium; hydroxides of other metals, such as aluminium and zinc; ammonia, organic amines such as unsubstituted or hydroxyl-substituted mono-, di-, or tri-alkylamines, dicyclohexylamine; tributyl amine; pyridine; N-methyl, N-ethylamine; diethylamine; triethylamine; mono-, bis-, or tris-(2-OH(Ci-C6)-alkylamine), such as NJM-dimethyl-N-(2-hydroxyethyl) amine or tri-(2-hydroxyethyl)amine; N-methyl-D-glucamine; morpholine; thiomorpholine; piperidine; pyrrolidine; and amino acids such as arginine, lysine, and the like. The invention also provides pharmaceutical compositions comprising an effective amount of a compound of Formula (I), (II), (III), (IV), (V), (VI), (VII), (VIII) or (IX) (e.g., including any of the formulae herein), or a pharmaceutically acceptable salt of said compound; and a pharmaceutically acceptable carrier. The carrier(s) are acceptable in the sense of being compatible with the other ingredients of the formulation and, in the case of a pharmaceutically acceptable carrier, not deleterious to the recipient thereof in an amount used in the medicament.

    [0158] Pharmaceutically acceptable carriers, adjuvants and vehicles that may be used in the pharmaceutical compositions of this invention include, but are not limited to, ion exchangers, alumina, aluminium stearate, lecithin, serum proteins, such as human serum albumin, buffer substances such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, salts or electrolytes, such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone, cellulose-based substances, polyethylene glycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropyleneblock polymers, polyethylene glycol and wool fat. It is also possible to, enhance the bioavailability if the compound using an amorphous form of the compound optionally formulated with a poloxamer, such as LUTPvOL and PLURONIC (BASF Corporation), or block copolymers of ethylene oxide and propylene oxide.

    [0159] The compound of the present invention may exist in a number of different crystalline polymorphs and the polymorph(s) with optimal pharmaceutical properties can be selected so all crystalline polymorphs of the compound of the present invention are incorporated herein.

    [0160] The pharmaceutical compositions of the invention include those suitable for oral, rectal, nasal, topical (including buccal and sublingual), vaginal or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) intrathecal or other intraspinal administration. In certain embodiments, the compound of the formulae herein is administered transdermally (e.g., using a transdermal patch or iontophoretic techniques). Other formulations may conveniently be presented in unit dosage form, e.g., tablets, sustained release capsules, and in liposomes. The molecule to be administered is brought into association with ingredients such as the carrier which may be a liquid carrier, liposomes or finely divided solid carriers, or both, and then, if necessary, shaping the product. Compositions of the present invention suitable for oral administration may be presented as discrete units such as capsules, sachets, or tablets each containing a predetermined amount of the active ingredient; a powder or granules; a solution or a suspension in an aqueous liquid or a nonaqueous liquid; an oil-in-water liquid emulsion; a water-in-oil liquid emulsion; packed in liposomes; or as a bolus, etc. Soft gelatin capsules can be useful for containing such suspensions, which may beneficially increase the rate of compound absorption. In the case of tablets for oral use, carriers that are commonly used include lactose and corn starch. Lubricating agents, such as magnesium stearate, are also typically added. For oral administration in a capsule form, useful diluents include lactose and dried cornstarch. When aqueous suspensions are administered orally, the active ingredient is combined with emulsifying and suspending agents. If desired, certain sweetening and/or flavoring and/or colouring agents may be added, for example if the composition is included in a lozenges a flavouring which is usually sucrose and acacia or tragacanth is used and for pastilles the active ingredient is included with an inert basis such as gelatin and glycerin, or sucrose and acacia.

    [0161] Compositions suitable for parenteral administration include aqueous and nonaqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and nonaqueous sterile suspensions which may include suspending agents and thickening agents.

    [0162] The formulations may be presented in unit-dose or multi-dose containers, for example, sealed ampules and vials, and may be stored in a freeze dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets. Such injection solutions may be in the form, for example, of a sterile injectable aqueous or oleaginous suspension. This suspension may be formulated according to techniques known in the art using suitable dispersing or wetting agents (such as, for example, Tween 80) and suspending agents. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenter ally-acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are mannitol, water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose, any bland fixed oil may be employed including synthetic mono- or diglycerides. Fatty acids, such as oleic acid and its glyceride derivatives are useful in the preparation of injectables, as are natural pharmaceutically-acceptable oils, such as olive oil or castor oil, especially in their polyoxyethylated versions. These oil solutions or suspensions may also contain a long-chain alcohol diluent or dispersant.

    [0163] The pharmaceutical compositions of this invention may be administered in the form of suppositories for rectal administration. These compositions can be prepared by mixing a compound of this invention with a suitable non-irritating excipient which is solid at room temperature but liquid at the rectal temperature and therefore will melt in the rectum to release the active components. Such materials include, but are not limited to, cocoa butter, 50 beeswax and polyethylene glycols.

    [0164] The pharmaceutical compositions of this invention may be administered by nasal aerosol or inhalation. Such compositions are prepared according to techniques well-known in the art of pharmaceutical formulation and may be prepared as solutions in saline, employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other solubilizing or dispersing agents known in the art.

    [0165] Topical administration of the pharmaceutical compositions of this invention is especially useful when the desired treatment involves areas or organs readily accessible by topical application. For topical application topically to the skin, the pharmaceutical composition should be formulated with a suitable ointment containing the active components suspended or dissolved in a carrier. Carriers for topical administration of the compounds of this invention include, but are not limited to, mineral oil, liquid petroleum, white petroleum, propylene glycol, polyoxyethylene polyoxypropylene compound, emulsifying wax, and water. Alternatively, the pharmaceutical composition can be formulated with a suitable lotion or cream containing the active compound suspended or dissolved in a carrier. Suitable carriers include, but are not limited to, mineral oil, sorbitan monostearate, polysorbate 60, cetyl esters wax, cetearyl alcohol, 2-octyldodecanol, benzyl alcohol, and water. The pharmaceutical compositions of this invention may also be topically applied to the lower intestinal tract by rectal suppository formulation or in a suitable enema formulation. Topically-transdermal patches and iontophoretic administration are also included in this invention.

    [0166] Application of the subject therapeutics may be local, so as to be administered at the site of interest. Various techniques can be used for providing the subject compositions at the site of interest, such as injection, use of catheters, trocars, projectiles, pluronic gel, stents, sustained drug release polymers or other device which provides for internal access. Accordingly, the compounds of this invention may be incorporated into compositions for coating an implantable medical device, such as prostheses, artificial valves, vascular grafts, stents, or catheters. Suitable coatings are typically biocompatible polymeric materials such as a hydrogel polymer, polymethyldisiloxane, polycaprolactone, polyethylene glycol, polylactic acid, ethylene vinyl acetate, and mixtures thereof. The coatings may optionally be further covered by a suitable topcoat of fluorosilicone, polysaccharides, polyethylene glycol, phospholipids or combinations thereof to impart controlled release characteristics in the composition.

    [0167] The compound of the present invention is administered in an effective amount which means that when administered in a proper dosing regimen, the amount is sufficient to treat the target disorder and this amount can vary according to the height and weight of the subject. Effective doses of the compounds of the present invention will also vary, as recognized by those skilled in the art, depending on the disease(s) treated, the severity of the disease, the route of administration, the sex, age and general health condition of the subject, excipient usage, the possibility of co-usage with other therapeutic treatments such as use of other agents and the judgment of the treating physician.

    [0168] It is also possible to co-administer the compound of the invention with one or more second therapeutic agents or treatments. The term co-administered as used herein means that the second therapeutic agent may be administered together with a compound of this invention as part of a single dosage form (such as a composition of this invention comprising a compound of the invention and an second therapeutic agent as described above) or as separate, multiple dosage forms. Alternatively, the additional agent may be administered prior to, consecutively with, or following the administration of a compound of this invention. It is possible that where a second therapeutic agent is administered to a subject, the effective amount of the compound of the invention or the second therapeutic agent that is required is less than its effective amount than when the agent or compound are administered on their own so by being able to give less drugs to the individual undesired side effects associated with high doses of either agent may be minimized. Other potential advantages include improved dosing regimens and/or reduced drug cost. The present invention overcomes problems of the prior art as there is a reduction in metabolism of the compound compared with that of its non-deuterated parent compound. This has the surprising effect that the specific deuterated compounds described are more neuroprotective compared with their non-deuterated parent compounds and also give rise to lower levels of neurotoxic metabolites so making the compound particularly attractive for administering to patients that have a long term illness.

    [0169] It is to be understood that the above embodiments have been provided only by way of exemplification of this invention, such as those detailed below, and that further modifications and improvements thereto, as would be apparent to persons skilled in the relevant art, are deemed to fall within the broad scope and ambit of the present invention described. Furthermore where individual embodiments are discussed, the invention is intended to cover combinations of those embodiments as well. The systems shown and described are not limited to the precise details and conditions disclosed. Method steps provided may not be limited to the order in which they are listed but may be ordered any way as to carry out the inventive process without departing from the scope of the invention. Furthermore, other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangements of the exemplary embodiments without departing from the scope of the invention as expressed in the appended claims.

    TABLE-US-00001 TABLE 1 Oxysterols and Cholestenoic Acids in Human CSF Oxysterols and cholestenoic acids identified by LC-ESI-MS.sup.n in CSF following SPE and charge-tagging with GP-hydrazine. In the absence of authentic standards presumptive identifications based on exact mass, MS.sup.n spectra and retention time are given. Samples from 12 individual control subjects () and a pool of fifteen different control subjects () were analysed. CSF from three SPG5 patients (*), and two health carriers, heterozygotes, with a single mutation in CYP7B1, (.Math.) were also analysed. Originating structure After cholesterol oxidase and GP-tagging Sterol Sterol Systematic name Mean Systematic (Common name, concentration Mass Formula name abbreviation) RT RRT AS ng/mL SE Note 522.3326 C.sub.33H.sub.44N.sub.3O.sub.4 7-Hydroxy-3-oxochol- 7-Hydroxy-3-oxochol- 2.06 0.34 Yes 0.230 0.030 1, 2, 3 text missing or illegible when filed 4-en-24-oic acid 3-GP 4-en-24-oic acid 0.507 0.088 (7H,3O-.sup.4-BA) 0.423 0.128 0.058 0.026* 534.3690 C.sub.33H.sub.48N.sub.3O.sub.3 7-Hydroxy-26-nor- 7-Hydroxy-26-nor 4.86 0.82 No 0.339 0.056 1, 2, text missing or illegible when filed cholest-4-ene-3,24-dione cholest-4-ene-3,24- 0.712 0.093 3, 4 3-GP dione 0.140 0.038 0.022 0.022* 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 24S-Hydroxycholest-4- Cholest-5-ene-3,24S- 7.43 1.26 Yes 0.024 0.003 5, 6 text missing or illegible when filed en-3-one 3-GP diol 0.075 0.003 (24S- 0.032 0.010 Hydroxycholesterol, 0.018 0.006* 24S-HC) 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 25-Hydroxycholest-4-en- Cholest-5-ene-3,25- 7.64 1.30 Yes 0.041 0.004 3, 5, 6 text missing or illegible when filed 3-one 3-GP diol 0.026 0.003 (25- 0.041 0.018 Hydroxycholesterol, 0.166 0.048* 25-HC) 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 26-Hydroxycholest-4-en- Cholest-5-ene-3,26- 7.99 1.36 Yes 0.042 0.006 3, 5, 6 text missing or illegible when filed 3-one 3-GP diol 0.146 0.003 (26- 0.215 0.032 Hydroxycholesterol, 0.915 0.224* 26-HC) 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 7-Hydroxycholest-4-en- Cholest-5-ene-3,7- 9.68 1.62 Yes 0.010 0.002 3, 5, 6 text missing or illegible when filed 3-one 3-GP diol 0.032 0.027 (7- 0.138 0.060 Hydroxycholesterol 0.079 0.022* 7-HC) 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 3-Hydroxycholest-5-en- 3-Hydroxycholest-5- 9.78 1.66 Yes 0.069 0.015 5, 6, 7 text missing or illegible when filed 7-one 7-GP en-7-one NM (7-Oxocholesterol, 7O- NM C) NM* 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 7-Hydroxycholest-4-en- Cholest-5-ene-3,7- 10.20 1.72 Yes 0.023 0.004 3, 5, 6 text missing or illegible when filed 3-one 3-GP diol 0.026 0.017 (7- 0.190 0.091 Hydroxycholesterol, 0.122 0.034* 7-HC) 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 6-Hydroxycholest-4-en- Cholest-4-ene-3,6-diol 10.52 1.77 Yes 0.036 0.006 3, 5, text missing or illegible when filed 3-one 3-GP or Cholest-5-ene-3,6- 0.149 00.042 6, 8 diol 1.419 1.174 (6-Hydroxycholesterol, 0.235 0.138* 6-HC) 546.3690 C.sub.34H.sub.48N.sub.3O.sub.3 3-Oxocholesta-4,6-dien- 3-Oxocholesta-4,6- 7.28 1.23 Yes 1.110 0.137 1, 3, text missing or illegible when filed 26-oic acid 3-GP dien-26-oic acid 2.047 0.312 5, 9 1.182 0.319 0.159 0.111* 546.3690 C.sub.34H.sub.48N.sub.3O.sub.3 3-Oxocholesta-4,6-dien- 3-Hydroxycholesta- 7.28 1.23 No 0.400 0.049 1, 2, text missing or illegible when filed 26-oic acid 3-GP 5,7-dien-26-oic acid 0.467 0.015 3, 10 0.213 0.092 0.079 0.045* 548.3847 C.sub.34H.sub.50N.sub.3O.sub.3 3-Oxocholest-4-en-26- 3-Hydroxycholest-5- 7.63 1.30 Yes 0.534 0.061 1, 3, 5 text missing or illegible when filed oic acid 3-GP en-26-oic acid (3- 1.458 0.095 HCA) 2.749 0.098 20.145 2.756* 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,25-Dihydroxycholest- 7,25- 5.71 0.96 Yes 0.014 0.001 1, 3, text missing or illegible when filed 4-en-3-one 3-GP Dihydroxycholest-4-en- 0.039 0.001 5, 11 3-one (7,25-diHCO) 0.039 0.002 ND* 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,25-Dihydroxycholest- Cholest-5-ene- 5.71 0.96 Yes ND 1, 3, text missing or illegible when filed 4-en-3-one 3-GP 3,7,25-triol 0.028 0.003 5, 11 (7,25- 0.045 0.034 Dihydroxycholesterol, 0.015 0.015* 7,25-diHC) 550.4003 C.sub.34H.sub.53N.sub.3O.sub.3 7,26-Dihydroxycholest- 7,26- 6.23 1.05 Yes 0.024 0.004 1, 3, 5 text missing or illegible when filed 4-en-3-one 3-GP Dihydroxycholest-4-en- 0.045 0.002 3-one (7,26-diHCO) 0.055 0.018 ND* 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,26-Dihydroxycholest- Cholest-5-ene- 6.23 1.05 Yes ND 1, 3, 5 text missing or illegible when filed 4-en-3-one 3-GP 3,7,26-triol 0.028 0.003 (7,26- 0.043 0.010 Dihydroxycholesterol, 0.005 0.003* 7,26-diHC) 562.3639 C.sub.34H.sub.48N.sub.3O.sub.4 24-Hydroxy-3- 24-Hydroxy-3- 4.05 0.68 No 0.395 0.051 1, 2, text missing or illegible when filed oxocholesta-4,6-dien-26- oxocholesta-4,6-dien- 0.160 0.035 3, 12 oic acid 3-GP 26-oic acid 0.313 0.067 0.031 0.031* 562.3639 C.sub.34H.sub.48N.sub.3O.sub.4 25-Hydroxy-3- 25-Hydroxy-3- 5.18 0.86 No 0.054 0.002 1, 2, text missing or illegible when filed oxocholesta-4,6-dien-26- oxocholesta-4,6-dien- 0.054 0.013 3, 13 oic acid 3-GP 26-oic acid ND ND* 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 3,7- 4.18 0.71 Yes 0.253 0.051 1, 3, 5 text missing or illegible when filed oxocholest-4-en-26-oic Dihydroxycholest-5-en- 0.555 0.027 acid 3-GP 26-oic acid (3,7- 0.402 0.100 diHCA) 0.054 0.043* 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 22,25-Dihydroxycholest- 3,22,25- 5.12 0.87 No 0.074 0.008 1, 2, text missing or illegible when filed 4-en-3,24-dione 3-GP Trihydroxycholest-5- 0.269 0.033 3, 14 en-24-one 0.211 0.053 0.223 0.044* 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 7-Hydroxy-3- 5.91 1.00 Yes 11.818 1.626 1, 3, text missing or illegible when filed oxocholest-4-en-26-oic oxocholest-4-en-26-oic 19.475 2.490 5, 9 acid 3-GP acid (7H,3O-CA) 20.156 7.774 2.492 1.316* 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 3,7- 5.91 1.00 Yes 0.773 0.103 1, 3, text missing or illegible when filed oxocholest-4-en-26-oic Dihydroxycholest-5-en- 5.5884 0.460 5, 10 acid 3-GP 26-oic acid (3,7- 4.547 1.941 diHCA) 0.472 0.438* 566.3952 C.sub.34H.sub.52N.sub.3O.sub.4 7,24(or26),25- 7,24(or26),25- 2.63 0.45 No 0.092 0.006 1, 2, text missing or illegible when filed Trihydroxycholest-4-en- Trihydroxycholest-4- 0.261 0.010 3, 15 3-one 3-GP en-3-one 0.089 0.089 ND* 578.3589 C.sub.14H.sub.48N.sub.3O.sub.5 7-Hydroxy-3,24- 7-Hydroxy-3,24- 2.34 0.39 No 0.068 0.005 1, 2, text missing or illegible when filed bisoxocholest-4-en-26- bisoxocholest-4-en-26- 0.200 0.029 3, 16 oic acid 3-GP oic acid 0.233 0.054 ND* 580.3745 C.sub.34H.sub.50N.sub.3O.sub.5 7,24-Dihydroxy-3- 7,24-Dihydroxy-3- 2.66 0.44 No 2.092 0.314 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic oxocholest-4-en-26-oic 3.506 0.540 3, 17 acid 3-GP acid 4.514 1.126 0.603 0.380* 580.3745 C.sub.34H.sub.50N.sub.3O.sub.5 7,25-Dihydroxy-3- 7,25-Dihydroxy-3- 3.64 0.61 No 0.401 0.068 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic oxocholest-4-en-26-oic 1.071 0.270 3, 18 acid 3-GP acid 1.204 0.665 0.191 0.157* 596.3694 C.sub.35H.sub.50N.sub.3O.sub.6 Trihydroxy-3- Trihydroxy-3- 2.15 0.27 No 0.063 0.008 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic oxocholest-4-en-26-oic 0.108 0.019 3, 19 acid 3-GP acid 0.036 0.007 0.059 0.023* RT = Retention time/min, RRT = Retention time relative to 7-hydroxy-3-oxocholest-4-en-26-oic acid, AS = Authentic standard, SE = Standard error of 12 patient samples or of three technical replicates of the pooled sample, NM = not measured, ND = not detected. In some cases the exact location of side-chain oxo and hydroxy groups is equivocal in which case the most likely location is shown in bold. The SPG5 patients were: Patient 2, GAG and 22332 in Table S3. Control heterozygotes were GNI and GAN, mother and father of GAG, in Table S3. 1. Quantitative estimate based on [.sup.2H.sub.6]cholest-5-ene-3,24(R/S)-diol internal standard. 2. Identification based on exact mass and MS.sup.n spectra. 3. Quantitative measurements based on GP-tagged 3-oxo-4-ene compounds giving similar ESI-MS response (9). 4. 26-Nor-sterol is a likely decomposition product of a 24-oxo-26-acid (see note 16). Possible alternatives to the 24-oxo group are an enol or epoxy group, all add 14 Da to the sterol structure. 5. Identification based on comparison with authentic standard. 6. Quantification based on [.sup.2H.sub.6]cholest-5-ene-3,24(R/S)-diol internal standard. 7. Under the conditions employed 3-hydroxy-7-oxo-5-ene sterols are not oxidised to their 3,7-bisoxo-4-ene equivalents. 8. Cholest-4-ene-3,6-diol and/or cholest-5-ene-3,6-diol are decomposition products of 3-hydroxycholestan-5,6-epoxide and cholestane-3,5,6-triol. Identification based on comparison with 6-hydroxycholest-4-en-3-one reference standard. 9. 7-Hydroxy-3-oxocholest-4-en-26-oic acid dehydrates to a minor degree to 3-oxocholesta-4,6-dien-26-oic acid. Thus, the total 7-hydroxy-3-oxocholest-4-en-26-oic acid corresponds to the sum of the two acids. 10. 3,7-Dihydroxychoest-5-en-26-oic acid dehydrates to a minor degree to 3-hydroxychoesta-5,7-dien-26-oic acid. Thus, the total 3,7-dihydroxychoest- 5-en-26-oic acid corresponds to the sum of the two acids. 11. Identification based on comparison with cholest-5-ene-3,7,25-triol and cholest-5-ene-3,7,25-triol reference standards. 12. The MS.sup.n spectra suggest hydroxylation of the C17 side-chain. 24-Hydroxy-3-oxocholesta-4,6-dien-26-oic acid is a likely dehydration product of 7,24- dihydroxy-3-oxocholest-4-en-26-oic acid (see note 17). 13. The MS.sup.n spectra suggest hydroxylation of the C17 side-chain. 25-Hydroxy-3-oxocholesta-4,6-dien-26-oic acid is a likely dehydration product of 7,25- dihydroxy-3-oxocholest-4-en-26-oic acid (see note 18). 14. The MS.sup.n spectra suggest a 3,22,25-trihydroxycholest-5-en-24-one or 3,z-dihydroxycholest-5-en-26-oic acid structure, where z is a side-chain hydroxylation. 15. The MS.sup.n spectra suggest dihydroxylation of the C17 side-chain, possibly at C-24 or C-26 and C-25. 16. The MS.sup.n spectra suggest a 24-oxo group. An alternative explanation is an enol or epoxy group, all add 14 Da to the sterol structure. 17. The MS.sup.n spectra suggest a hydroxyl group on the C17 side-chain, probably at C-24. 18. The MS.sup.n spectra suggest a hydroxyl group on the C17 side-chain, probably at C-25. 19. MS.sup.n spectra of insufficient quality to define location of substituents. text missing or illegible when filed indicates data missing or illegible when filed

    TABLE-US-00002 TABLE 2 Oxysterols and Cholestenoic Acids in Human Plasma (Serum) Oxysterols and cholestenoic acids identified by LC-ESI-MS.sup.n in plasma (serum) following SPE and charge-tagging with GP-hydrazine. In the absence of authentic standards presumptive identifications based on exact mass, MS spectra and retention time are given. Control samples from 56 adults () and 3 children () were analysed. Data is also given for two health carriers, heterozygotes, with single mutations in CYP7B1 (.Math.). Data is given for seven adults showing clinically pure HSP SPG5 plus two adults with complicated HSP SPG5 (*) and three infants suffering from 07AHD (). Data is also given four patients suffering from CTX (). Clinical data is given in Table S3. Oxysterols and cholestenoic acids identified by LC-ESI-MS.sup.n in plasma (serum) following SPE and charge-tagging with GP-hydrazine. In the absence of authentic standards presumptive identifications based on exact mass, MS spectra and retention time are given. Control samples from 56 adults () and 3 children () were analysed. Data is also given for two health carriers, heterozygotes, with single mutations in CYP7B1 (.Math.). Data is given for seven adults showing clinically pure HSP SPG5 plus two adults with complicated HSP SPG5 (*) and three infants suffering from 07AHD (). Data is also given four patients suffering from CTX (). Clinical data is given in Table S3. After cholesterol oxidase and GP-tagging Originating structure Sterol Sterol Systematic Mean Systematic name (common concentration Mass Formula name name, abbreviation) RT RRT AS ng/mL SE 506.3377 C.sub.31H.sub.44N.sub.3O.sub.3 3-Oxochol-4-en-24-oic droxychol-5-en-24-oic acid 4.57 0.75 Y 0.83 0.14 1, 2, text missing or illegible when filed acid 3-GP .sup.5-BA) 1.55 0.38 3 5.73 0.24 22.28 4.53* 178.85 88.40 ND 522.3326 C.sub.31H.sub.44N.sub.3O.sub.4 7-Hydroxy-3-oxochol- 7-Hydroxy-3-oxochol-4-en- 2.18 0.36 Y 1.17 0.23 1, 2, text missing or illegible when filed 4-en-24-oic acid 3-GP 24-oic acid (7H,3O-.sup.4-BA) 1.51 0.67 3 1.27 0.29 1.24 0.32* 11.38 7.33 ND 522.3326 C.sub.31H.sub.44N.sub.3O.sub.4 7-Hydroxy-3-oxochol- 3,7-Dihydroxychol-5-en-24- 2.18 0.36 Y 1.52 0.34 1, 2, text missing or illegible when filed 4-en-24-oic acid 3-GP oic acid (3,7-diH-.sup.5-BA) 1.53 0.63 3 1.25 0.02 0.75 0.42* 2.91 2.38 ND 532.3898 C.sub.34H.sub.50N.sub.3O.sub.2 Cholest-4-ene-3,24- Cholest-4-ene-3,24-dione 7.91 1.27 Y 0.36 0.03 1, 2, text missing or illegible when filed dione 3-GP ND 3, 4 ND ND* ND ND 532.3898 C.sub.34H.sub.50N.sub.3O.sub.2 Cholest-4-ene-3,24- 3-Hydroxycholest-5-en-24- 7.91 1.27 Y 0.24 0.06 1, 2, text missing or illegible when filed dione 3-GP one ND 3, 4 (24-Oxocholesterol, 24O-C) 0.62 0.10 0.37 0.10* 38.74 4.03 0.29 0.23 534.3690 C.sub.33H.sub.48N.sub.3O.sub.3 7-Hydroxy-26-nor- 7-Hydroxy-26-nor-cholest-4- 5.16 0.83 N 0.2 0.2 1, 2, text missing or illegible when filed cholest-4-en-3,24-dione ene-3,24-dione ND 5, 6 3-GP 0.10 0.10 0.03 0.02* 5.10 4.27 ND/ND/ND/ ND 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 24S-Hydroxycholest-4- Cholest-3-ene-3,24S-diol 7.60 1.24 Y 7.11 0.40 3, 7 text missing or illegible when filed en-3-one 3-GP (24S-Hydroxycholesterol, 24S- 12.67 0.26 HC) 8.30 0.07 9.13 1.94* 136.18 43.06 10.11 3.77 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 25-Hydroxycholest-4- Cholest-5-ene-3,25-diol 7.91 1.29 Y 3.96 0.27 2, 3, text missing or illegible when filed en-3-one 3-GP (25-Hydroxycholesterol, 25- 6.04 0.97 7, 8 HC) 1.28 0.06 49.90 11.38* 336.97 86.56 3.60 1.23 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 26-Hydroxycholest-4- Cholest-5-ene-3,26-diol 8.14 1.33 Y 18.99 0.85 2, 3, text missing or illegible when filed en-3-one 3-GP (26-Hydroxycholesterol, 26- 10.22 2.65 7 HC) 38.98 1.39 97.75 7.28* 1320.94 212.61 ND 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 7-Hydroxycholest-4- 7-Hydroxycholest-4-en-3-one 9.84 1.60 Y 2.62 0.75 2, 3, text missing or illegible when filed en-3-one 3-GP (7-HCO) ND 7, 9 ND ND* ND/ND/ND ND 534.4054 C.sub.34H.sub.53N.sub.3O.sub.3 7-Hydroxycholest-4- Cholest-5-ene-3,7-diol 9.84 1.60 Y 1.02 0.58 2, 3, text missing or illegible when filed en-3-onc 3-GP (7-Hydroxycholesterol, 7- ND 7, 9 HC) 0.70 0.03 12.77 12.52* 58.26 45.96 24.01 7.52 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 3-Hydroxycholest-5- 3-Hydroxycholest-5-en-7-one 9.93 1.62 Y 4.98 2.25 1, 3, text missing or illegible when filed en-7-one 7-GP (7-Oxocholesterol, 7O-C) ND 9 2.78 0.43 0.77 0.29* 25.00 19.60 34.35 24.15 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 7-Hydroxycholest-4- 7-Hydroxycholest-4-en-3-one 10.39 1.69 Y 2.43 0.37 2, 3, text missing or illegible when filed en-3-one 3-GP (7-HCO) ND 7, 9 4.23 4.23 3.19 0.79* 0.09 0.09 70.77 39.58 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 7-Hydroxycholest-4- Cholest-5-ene-3,7-diol 10.39 1.69 Y 1.30 0.39 2, 3, text missing or illegible when filed en-3-one 3-GP (7-Hydroxycholesterol, 7- ND 7, 9 HC) 1.48 0.53 6.75 6.21* 36.39 30.67 78.25 51.06 534.4054 C.sub.34H.sub.52N.sub.3O.sub.2 6-Hydroxycholest-4-en- Cholest-4-ene-3,6-diol or 10.79 1.75 Y 1.96 0.50 2, 3, text missing or illegible when filed 3-one 3-GP Cholest-5-ene-3,6-diol ND 7, 9, (6-Hydroxycholesterol, 6-HC) 0.31 0.31 10 0.22 0.19* ND 3.83 2.52 546.3690 C.sub.34H.sub.48N.sub.3O.sub.3 3-Oxocheolesta-4,6-dien- 3-Oxocholesta-4,6-dien-26-oic Y 8.10 0.74 1, 2 text missing or illegible when filed 26-oic acid 3-GP acid 2.57 1.56 3, 11 7.55 1.60 7.58 1.96* 16.56 9.53 ND 546.3690 C.sub.33H.sub.48N.sub.3O.sub.3 3-Oxocholesta-4,6-dien- 3-Hydroxycholesta-5,7-dien- N 6.20 0.59 1, 2, text missing or illegible when filed 26-oic acid 3-GP 26-oic acid 2.56 0.60 5, 12 1.54 0.75 1.73 1.03* ND ND 548.3847 C.sub.34H.sub.50N.sub.3O.sub.3 3-Oxocholest-4-en-26- 3-Hydroxycholest-5-en-26- 7.84 1.28 Y 81.12 4.31 1, 2, text missing or illegible when filed oic acid 3-GP oic acid (3-HCA) 37.21 7.77 3 144.45 38.53 368.40 65.27* 2909.35 675.10 ND 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,25-Dihydroxycholest- 7,25-Dihydroxycholest-4-en- 5.87 0.96 Y 1.10 0.32 1, 2, text missing or illegible when filed 4-en-3-one 3-GP 3-one (7,25-diHCO) 2.51 1.83 3 0.98 0.18 ND* ND 4.64 2.89 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,26-Dihydroxycholest- 7,26-Dihydroxycholest-4-en- 6.38 1.04 Y 5.10 0.56 1, 2, text missing or illegible when filed 4-en-3-one 3-GP 3-one (7,26-diHCO) 5.02 2.52 3 3.95 2.06 1.32 0.26* 0.13 0.13 ND 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,26-Dihydroxycholest- Cholest-5-ene-3,7,26-triol 6.38 1.04 Y 0.92 0.49 1, 2, text missing or illegible when filed 4-en-3-one 3-GP (7,26-Dihydroxycholesterol, 1.27 0.26 3 7,26-diHC) 0.49 0.04 0.20 0.10* 0.57 0.57 ND 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,12- 7,12-Dihydroxycholest-4- 9.23 1.51 Y ND 1, 2, text missing or illegible when filed Dihydroxycholest-4-en en-3-one (7,12-diHCO) ND 3, 3-one 3-GP 0.08 0.08 ND* ND 381.62 250.33 550.4003 C.sub.34H.sub.52N.sub.3O.sub.3 7,12- Cholest-5-ene-3,7,12-triol 9.23 1.51 Y ND 1, 2, text missing or illegible when filed Dihydroxycholest-4-en- (7,12-Dihydroxycholesterol, ND 3, 3-one 3-GP 7,12-diHC) 0.03 0.03 ND* ND 95.60 76.01 562.3639 C.sub.34H.sub.48N.sub.3O.sub.4 24-Hydroxy-3 24-Hydroxy-3-oxocholesta- 4.39 0.71 N 0.2 0.2 1, 2, text missing or illegible when filed oxocholesta-4,6-dien-26- 4,6-dien-26-oic acid 0.2 0.2 5, 13 oic acid 3-GP ND 0.29 0.17* ND ND 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 3,7-Dihydroxycholest-5-en- 4.45 0.73 Y 1.67 0.32 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic 26-oic acid (3,7-diHCA) 3.11 1.00 3 acid 3-GP 3.76 2.02 2.47 0.58* 8.83 4.42 ND 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 22,25-Dihydroxycholest- 3,22,25-Trihydroxycholest-5- 5.44 0.88 N 5.37 0.64 1, 2, text missing or illegible when filed 4-en-3,24-dione 3-Gp en-24-one 4.74 1.59 5, 14 4.78 0.05 15.70 3.30* 29.77 4.06 7.10 1.29 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 7-Hydroxy-3-oxocholest-4- 6.11 1.00 Y 63.27 6.22 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic en-26-oic acid (7H,3O-CA) 48.32 16.97 3, 11 acid 3-GP 56.68 9.94 33.95 5.81* 29.79 14.82 ND 564.3796 C.sub.34H.sub.50N.sub.3O.sub.4 7-Hydroxy-3- 3,7-Dihydroxycholest-5-en- 6.11 1.00 Y 39.40 3.95 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic 26-oic acid (3,7-diHCA) 28.83 8.40 3, 12 acid 3-GP 19.76 8.73 5.21 3.09* 1.16 1.16 ND 566.3952 C.sub.34H.sub.52N.sub.3O.sub.4 7,24(or26),25- 7,24(or26),25- 2.84 0.46 N 0.65 0.11 1, 2, text missing or illegible when filed Trihydroxycholest-4-en- Trihydroxycholest-4-en-3-one 3.38 2.36 5, 15 3-one 3-GP NM ND* 1.60 0.80 ND 580.3745 C.sub.34H.sub.50N.sub.3O.sub.5 7,24-Dihydroxy-3- 7,24-Dihydroxy-3- 2.89 0.47 N 0.2 0.2 1, 2, text missing or illegible when filed oxocholest-4-en-26-oic oxocholest-4-en-26-oic acid 0.5 0.44 5, 16 acid 3-GP 0.95 0.13 ND* ND ND RT = Retention time/min; RRT = Retention time relative to 7-hydroxy-3-oxocholest-4-en-26-oic acid; AS = Authentic standard, Y = Yes, N = No; SE = Standard error of the mean; ND = Not detected; NM = Not measured. In some cases the exact location of the side-chain oxo or hydroxy groups is equivocal in which case the most likely location is shown in bold. 1. Quantitative estimate based on [.sup.2H.sub.6]cholest-5-ene-3,24(R/S)-diol internal standard. 2. Quantitative measurements based on GP-tagged 3-oxo-4-ene compounds giving similar ESI-MS response (9). 3. Identification based on comparison with authentic standard. 4. 24S,25-Epoxycholesterol can isomerise to 3-hydroxycholest-5-en-24-one during sample preparation. 5. Identification based on exact mass and MS.sup.n spectra. 6. 26-Nor-sterol is a likely decomposition product of a 24-oxo-26-acid. Alternatives to the oxo group are an enol or epoxy group, all add 14 Da to the sterol structure. 7. Quantification based on [.sup.2H.sub.6]cholest-5-ene-3,24(R/S)-diol internal standard. 8. There is some tailing of the 24S -hydroxy cholesterol peak into the 25 -hydroxy cholesterol peak, thus, values for 25- hydroxycholesterol are likely to be overestimated particularly when concentrations of 24S-hydroxy cholesterol greatly exceed those of 25-hydroxycholesterol. 9. May be underestimation of levels of late eluting oxysterols. 10. Cholest-4-ene-3,6-diol and/or cholest-5-ene-3,6-diol are decomposition products of 3-hydroxycholestan-5,6-epoxide and cholestane-3,5, 6P-triol. Identification based on comparison with 6P-hydroxycholest-4-en-3-one reference standard. 11. 7-Hydroxy-3-oxocholest-4-en-26-oic acid dehydrates to a minor degree to 3-oxocholesta-4,6-dien-26-oic acid. Thus, the total 7-hydroxy-3-oxocholest-4-en-26-oic acid corresponds to the sum of the two acids. 12. 3,7-Dihydroxychoest-5-en-26-oic acid dehydrates to a minor degree to 3-hydroxychoesta-5,7-dien-26-oic acid. Thus, the total 3,7-dihydroxychoest-5-en-26-oic acid corresponds to the sum of the two acids. 13. The MS.sup.n spectra suggest hydroxylation of the C17 side-chain. 24-Hydroxy-3-oxocholesta-4,6-dien-26-oic acid is a likely dehydration product of 7,24-dihydroxy-3-oxocholest-4-en-26-oic acid (see note 16). 14. The MS.sup.n spectra suggest a 3,22,25-trihydroxycholest-5-en-24-one or 3,z-dihydroxycholest-5-en-26-oic acid structure, where z is a side-chain hydroxylation. 15. The MS.sup.n spectra suggest dihydroxylation of the C17 side-chain, possibly at C-24 or C-26 and C-25. 16. The MS.sup.n spectra suggest a hydroxy group on the C17 side-chain, probably at C-24. text missing or illegible when filed indicates data missing or illegible when filed

    TABLE-US-00003 TABLE 3 Mutations in SPG5, Q7HD and CTX Patients Studied Sample code Mutation Reference Family Comment HSP P4505 II-1 (sister) Compound heterozygous Amoldi et al (Clin P4505 Pure HSP (serum analysed) CFP7B1 c260G>T/p.G87V Genet 2012; c.889A>G/p.T297A 81(2):150-7) P4505 11-2 (sister) Compound heterozygous Amoldi et al P4505 Pure HSP (serum analysed) CYP7B1 (supra) c.260G>T/p.G87V c.889A>G/p.T297A P52405 Homozygous CYP7B1 Amoldi et al P52405 Complicated HSP (serum c.1328G>C/p.443A (supra.) analysed) Patient 2 (female) Homozygous CYP7B1 Schle et al Complicated HSP (serum c.825T>A/p.Y275X (J Lipid Res and CSF analysed) 2010; 51(4):819-23.) AC (male) Homozygous CYP7B1 Present work Pure HSP (plasma analysed) c.889A>G/p.T297A P II-1 (male) Homozygous CYP7B1 Criscuolo et al Family P Pure HSP (plasma analysed) c.806delA/p.D269VfsX282 (J Neurol 2009; 256(8):1252-7) S II-3 (female) Homozygous CYP7B1 Criscuolo et al Family S Pure HSP (plasma analysed) c.806delA/p. D269VIX282 (supra) Si II-1 (male) Homozygous CYP7B1 Criscuolo et al Family Pure HSP (plasma analysed) c.1362insT/p.A453CfsX470 (supra.) Si GAG (male) Compound heterozygous Present work Family G Pure HSP (serum and CSF CYP7B1 analysed) c.250delC/p.L84FfsX6 c.266A>C/p.Y89S O7AHD JP (Infant male) Homozygous CYP7B1 Ueki et al (J O7AHD on treatment with c.538C>T/p.R112X Pediatr UDCA (plasma analysed) Gastroenterol Nutr 2008; 46(4):465-9) LT (Infant female) Compound heterozygous Mizuochi et al O7AHD on treatment with CYP7B1 (Liver UDCA (plasma analysed) c.538C>T/p.R112X Transp 2011; c.1453C>T/p.R417C 17(9):1059-65) JI (Infant male) Homozygous CYP7B1 Chong et al (J O7AHD on treatment with c1249C>T/p.R417C Inherit Metab UDCA (plasma analysed) Dis 2010; 33(Suppl 1):S- 382) Heterozygote (healthy) Controls GAN (male) Heterozygous CYP7B1 Present work Family G Father of GAG, unaffected c.250delC/p.L84FfsX6 (serum and CSF analysed) GNI (female) Heterozygous CYP7B1 Present work Family G Mother of GAG, unaffected c.266A>C/p.Y89S serum and CSF analysed) GPO (male) Heterozygous CYP7B1 Present work Family G Brother of GAG, unaffected c.266A>C/p.Y89S (serum analysed) CTX 8876 Adult (female) Homozygous CYP27A1 Present work Family CTX c.526delG 887 On treatment with CDCA and simvastatin (plasma analysed) 8875 Adult (male) Homozygous CYP27A1 Present work Family CTX c.526delG 887 On treatment with CDCA and simvastatin (plasma analysed) 8577 Child (male) Homozygous CYP27A1 Bourkiza et al CTX c.1184+1G>A (16) Not on treatment (plasma analysed) S2 Child (male) Homozygous CYP27A1 Present work CTX IVS6+1G>A Not on treatment, Diagnosis based on clinical and biochemical grounds Mulation analysis performed on affected brother (plasma analysed)

    TABLE-US-00004 TABLE 4 Cholestenoic Acids in Cyp7b1/ and Cyp27al/ Mouse Brain and Plasma Cholestenoic acids identified by LC-ESI-MS following SPE and charge-tagging with GP-hydrazine. Mouse Mean concentration in Mean concentration in Sterol age brain (ng/mg SD) plasma (ng/mL SD) Systematic name (abbreviation) (months) WT Cyp7b1/ WT Cyp7b1/ Note 3-Hydroxycholest-5-en-26-oic 13 0.01 0.00 0.12 0.02*** 1.97 0.72 7.32 1.50*** 1, 2, acid (3-HCA) 23 0.01 0.00 0.15 0.01*** 1.75 0.50 6.69 2.64*** 3 7-Hydroxy-3-oxocholest-4-en- 13 ND ND 25.89 10.9 14.21 3.76 1, 2, 26-oic acid (7H,3O-CA) 23 ND ND 125.19 9.44 20.73 1.77 3 3,7-Dihydroxycholest-5-en- 13 ND ND ND ND 1, 2, 26-oic acid (3,7-diHCA) 23 ND ND ND ND 3 WT Cyp27al/ WT Cyp27al/ 3-Hydroxycholest-5-en-26-oic 3 ND ND 3.56 1.22 ND** 2, 3, acid (3-HCA) ND ND 4 7-Hydroxy-3-oxocholest-4-en- 3 ND ND 28.96 7.22 5.23 1.07** 2, 3, 26-oic acid (7H,3O-CA) ND ND 4 3,7-Dihydroxycholest-5-en- 3 ND ND ND ND 2, 3, 26-oic acid (3,7-diHCA) ND ND ND ND 4 1. Wild type (WT) Cyp7b1/ mouse plasma (13 months, n = 5; 23 months, n = 4) and brain (13 months, n = 3; 23 months, n = 4) 2. Data are means SD, *, p < 0.05; **, p < 0.01; ***, p < 0.001 compared to same age WT. 3. Quantification was by stable isotope dilution mass spectrometry using deuterated 24(R/S)-hydroxy cholesterol as the internal standard. 4. Samples were from wild type (WT) and Cyp27l/ mice at 3 months, n = 3.