PHARMACEUTICAL COMPOSITION AND METHOD FOR REGENERATING MYOFIBERS IN THE TREATMENT OF MUSCLE INJURIES
20220175806 · 2022-06-09
Inventors
Cpc classification
A61P9/04
HUMAN NECESSITIES
A61K31/704
HUMAN NECESSITIES
A61K35/34
HUMAN NECESSITIES
A61K31/56
HUMAN NECESSITIES
A61K31/192
HUMAN NECESSITIES
International classification
A61K31/704
HUMAN NECESSITIES
A61K31/192
HUMAN NECESSITIES
A61K31/56
HUMAN NECESSITIES
A61K35/34
HUMAN NECESSITIES
Abstract
A pharmaceutical composition and method for regenerating cardiomyocytes in treating or repairing heart muscle damages cause by an ischemic disease. The pharmaceutical composition contains an active ingredient compound with a backbone structure of Formula (I). The active ingredient compound is capable of (a) increasing viability of myogenic precursor cells to enable said precursor cells to survive through an absolute ischemic period; (b) reconstituting a damaged blood supply network in said heart region where said injured muscle is located; and (c) enhancing cardiomyogenic differentiation efficiency of said precursor cells down cardiac linage, said steps being performed simultaneously or in any particular order.
Claims
1. A method of regenerating myocytes or myocardia in the heart of a mammalian subject suffering an injured heart muscle, comprising a step of administering an effective amount of a compound with a backbone structure showing in Formula (I) or a functional derivative of said compound. ##STR00004##
2. The method of claim 1, wherein said compound is said backbone structure itself without any substitution.
3. The method of claim 1, wherein said compound is selected from the group consisting of: ##STR00005## ##STR00006##
4. The method of claim 3, wherein said compound is: ##STR00007##
5. The method of claim 4, wherein said injured heart muscle is caused by an ischemic event.
6. The method of claim 5, wherein said ischemic event is myocardial infarction.
7. The method of claim 1, wherein said myocytes or myocardia are regenerated in a process comprising one or more steps of (a) increasing viability of myogenic precursor cells to enable said precursor cells to survive through an absolute ischemic period; (b) reconstituting a damaged blood supply network in said heart region where said injured muscle is located; and (c) enhancing cardiomyogenic differentiation efficiency of said precursor cells down cardiac linage, said steps being performed simultaneously or in any particular order.
8. The method of claim 7, wherein said myogenic precursor cells are mesenchymal stem cells coming from bone marrow through blood circulation.
9. The method of claim 1, further comprising the steps of: (a) obtaining a plurality of stem cells; (b) contacting said stem cells with said compound or said functional derivative for a period of time; and (c) transplanting said cells into an infarcted or damaged heart tissue of said mammalian subject.
10. The method of claim 1, further comprising the steps of: (a) formulating said compound or said functional derivative into a dosage form and (b) systematically administering said compound or said functional derivative in said dosage form to said mammalian subject.
11. The method of claim 10, wherein said dosage form is selected from the group consisting of tablet, capsule, injection solution, syrup, suspension and powder.
12. The method of claim 1, further comprising the steps of: (a) culturing a plurality of MSCs or endothelial cells in a culture medium containing said compound or said functional derivative for a period of time; (b) collecting said culture medium, containing secretary proteins from said MSCs or endothelial cells; and (c) administering or delivering said medium to heart tissues in a infarct area.
13. The method of claim 1, wherein at least 95% by weight of said composition is identified compounds.
14. The method of claim 1, further comprising adding a piece of information on usefulness of said compound, wherein said information indicates that said compound is beneficial to a human suffering or having suffered a heart disease.
15. The method of claim 1, further comprising adding a piece of information on usefulness of said compound, wherein said information indicates that said compound is beneficial to regenerate myocytes or myocardia in the heart of said mammalian subject.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0021]
[0022]
[0023]
[0024]
[0025]
[0026]
[0027]
DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS
I. Experiment Procedures
[0028] All protocols used in the present invention conformed to the Guide for the Care and Use of Laboratory Animals published by the U.S. National Institutes of Health, and were approved by the Animal Experimental Ethical Committee of The Chinese University of Hong Kong.
[0029] For the following discussion, CMF refers to the base compound (or backbone compound) of the present invention. Its chemical structure is defined by formula (I) shown in the above.
[0030] Obtaining Compounds of the Present Invention:
[0031] The compounds can be prepared from plants, although it may possible to make it through chemical synthesis.
[0032] As an example for illustrating the process of preparing the compounds from natural resources, the following provides details involved in CMF's isolation and purification from one plant species, Geum japonicum. Other plants that may contain CMF or variants include, for example, Acaena pinnatifida R. et P., Agrimonia pilosa Ledeb, Asparagus filicinus, Ardisia japonica, Campsis grandiflora, Campylotropis hirtella (Franch. Schindl.), Caulis sargentodoxae, Cedrela sinensis, Chaenomeles sinensis KOEHNE, Debregeasia salicifolia, Eriobotrya japonica calli, Eriobotrya japonica LINDL. (Rosaceae), Goreishi, Leucoseptrum stellipillum, Ludwigia octovalvis, Perilla frutescens, Perilla frutescens (L.) Britt. (Lamiaceae), Physocarpus intermedius Potentilla multifida L., Poterium ancistroides, Pourouma guianensis (Moraceae), Rhaponticum uniflorum, Rosa bella Rehd. et Wils., Rosa laevigata Michx, Rosa rugosa, Rubus alceaefolius Poir, Rubus allegheniensis, Rubus coreanus, Rubus imperialis, Rubus imperialis Chum. Schl. (Rosaceae), Rubus sieboldii, Rumex japonicus, Salvia trijuga Diels, Strasburgeria robusta, Strawberry cv. Houkouwase, Tiarella polyphylla, Vochysia pacifica Cuatrec, Zanthoxylum piperitum, etc.
[0033] Isolation of Cardiotnyogenic Factor (CMF) from Geumjaponicutn:
[0034] Referring to
[0035] Preparation of MSCs for Transplantation:
[0036] The MSCs were cultured with CMF (10 μg/mL in growth medium) for 6 days. In parallel, the control MSCs were cultured in growth medium containing equivalent volume of 5% DMSO. On day 2, expression of endogenous phospho-Aktl was assessed by immunocytochemistry and Western blot. On day 4, myogenic differentiation was assessed by immunocytochemistry and Western blot against MEF2, which were further confirmed by immunocytochemistry and Western blot with an antibody specific to MHC on day 6. On day 3, both the CMF-pretreated MSCs and the control MSCs were labeled with CM-DiI in culture and made ready for transplantation.
[0037] Preparation of Bone Marrow Mesenchymal Stein Cells:
[0038] The tibias/femur bones were removed from Sprague-Dawley (SD) rats and the bone marrow (BM) was flushed out of the bones with IMDM culture medium containing 10% heat inactivated FBS (GIBCO) and 1% penicillin/streptomycin. The BM was thoroughly mixed and centrifuged at 1500 rpm for 5 minutes. The cell pellet was suspended in 5 ml growth medium. The cell suspension was carefully put on 5 mL Ficoll solution and centrifuged at 200 rpm for 30 min. The second layer, which contains BM cells was transferred into a tube and washed twice with PBS to remove Ficoll (1200 rpm for 5 minutes). The cell pellet was resuspended in IMDM culture medium containing 10% heat inactivated FBS (GIBCO) and 1% penicillin/streptomycin antibiotic mixture. After 24 hours culture in a 37° C. incubator with 5% CO2, the non-adherent cells are discarded and the adherent cells are cultured by changing medium once every 3 days and the cells became nearly confluent after 14 days of culture. This was the BM cells, referred to as MSCs in the following, which were used for in vitro and in vivo studies conducted in the present disclosure.
[0039] Western Blot Analysis:
[0040] Whole cell extracts of the CMF-treated cells or control cells were prepared by lysing the cells with 3 times packed cell volume of lysis buffer (50 mM Tris, pH 7.5, 150 mM NaCl, 1 mM EDTA, 1 mM EGTA, 1% Nonidet P-40, 10% glycerol, 200 mM NaF, 20 mM sodium pyrophosphate, 10 mg/mL leupeptin, 10 mg/mL aprotinin, 200 mM phenylmethylsulfonyl fluoride, and 1 mM sodium orthovanadate) on ice for 30 minutes. Protein yield was quantified by Bio-Rad DC protein assay kit (Bio-Rad). Equal amounts (30 μg) of total protein were size-fractionated by SDS-PAGE and transferred to PVDM membranes (Millipore). The blots were blocked with phosphate-buffered saline plus 0.1% (vol/vol) Tween 20 (PBST) containing 5% (wt/vol) milk powder (PBSTM) for 30 minutes at room temperature and probed for 60 minutes with specific primary antibodies against rat phospho-Aktl (mouse) or rat MHC (mouse, Sigma-Aldrich), diluted 1:1000 in PBSTM. After washing extensively in PBST, the blots were probed by horseradish peroxidase-coupled anti-mouse IgG (Amersham Biosciences) (1/1000 dilution in PBSTM, 60 min), extensively washed with PBST, and developed by chemiluminescence.
[0041] Transplantation of the CMF Pretreated MSCs to the Heart Tissue:
[0042] The Sprague-Dawley (SD) rats were used and all animal procedures were approved by the University Animal Committee on Animal Welfare. Each rat was anesthetized with intraperitoneal pentobarbital (50 mg/kg), intubated, and mechanically ventilated with room air using a Harvard ventilator (model 683). After a left thoracotomy, myocardial infarction was induced by permanent ligation of left anterior descending (LAD) coronary artery. The 5×10.sup.5 DiI labeled CMF-pretreated MSCs (32 rats) suspended in saline were injected into three sites of the distal myocardia (the ischemic region) of the ligated artery immediate after the ligation respectively (test group). The control rats were injected with an equivalent amount of Dil labeled non-treated control MSCs (32 rats) suspended in saline at the same location and timing. For sham ischemia (32 rats), thoracotomy was performed without LAD ligation. Sixteen rats subject to no-treatment were set as normal control.
[0043] Half of the experimental rats from different groups were sacrificed according to experimental plan on day 7 and day 14 post-infarction after assessment of their heart function by echocardiography measurements. The hearts of the sacrificed rats were removed, washed with PBS and photographed respectively. All the specimens harvested were paraffin embedded and sectioned for tracing the signals of DiI and examination of revascularization, infarct size and regeneration of myocardia. If the regenerating cells were DiI positive, further MHC immunohistochemical staining was performed to confirm their cardiomyogenic differentiation.
[0044] Colocalization of the DiI label and cardiac-specific marker expression were examined with a confocal microscope (ZEISS, LSM 510 META). Briefly, the sections were immunohistochemically stained with rat-specific troponin I antibodies. The confirmation of cardiomyogenic differentiation of the Dil labeled transplanted MSCs forming regenerating myocardia was carried out by merging the Dil-positive cells, indicating their donor cell origin, with the specific positive staining of cardiac terminal differentiation marker-troponin I useing confocal microscopic examination, implying their cardiomyogenic differentiation of these transplanted cells.
[0045] CMF Direct Treatment in MI Model:
[0046] Thirty-two SD rats were randomly divided into four groups: normal group, sham group, CMF-treated group and non-treated control group (8 rats each). Rats were anesthetized with intraperitoneal pentobarbital (50 mg/kg), intubated, and mechanically ventilated with room air using a Harvard ventilator (model 683). After a left thoracotomy, myocardial infarction was induced by permanent ligation of left anterior descending (LAD) coronary artery. CMF in 5% DMSO (0.1 ml, containing 0.1 mg CMF) was injected into the distal myocardium (the ischemic region) of the ligated artery in 8 rats immediate after the ligation (CMF-treated group). Another 8 rats were injected with an equivalent amount of 5% DMSO at the same location and timing as non-treated control group. For sham ischemia, thoracotomy was performed on 8 rats without LAD ligation. Further 8 rats without any treatment were set as normal group.
[0047] Conditioned Medium Containing Secretary Proteins from MSCs or Other Cells Induced by CMF:
[0048] The MSCs were treated with 10 μg/ml CMF for 24 hours to activate/upregulate gene expressions and then washed thoroughly to remove residue of CMF. Then 5 ml of fresh growth medium was added to the culture and collected after another 3 days of culturing. The collected medium was referred to as conditioned medium. The 5 ml of conditioned medium was condensed to a volume of 1 mL, and was used as a treatment agent in the heart infarction animal model as described above. Briefly, after a left thoracotomy and ligation of LAD, 0.2 mL of the conditioned medium was injected immediately into the distal part of ligation. Fresh growth medium was used as control.
[0049] Bone Marrow Replacement with Labeled MSCs:
[0050] Sixteen 5-week old SD rats were used for bone marrow transplantation. Recipient rats were irritated by 9.5 Gy of gamma irradiation from a 137Cs source (Elite Grammacell 1000) at a dosage of 1.140 Gy/min to completely destroy the bone marrow derived stem cells of the rat. DU-labeled MSCs (2×10.sup.8 cells suspended in 0.3 ml PBS) were then injected through tail vein within 2 hours after irritation using a 27-gauge needle. One week after irritation and transplantation, the rats with DiI-labeled bone marrow were divided into two groups: one to be treated directly with CMF and the other as control without treatment. Heart infarction surgery and treatment scheme were performed as described above. The experiment was terminated on day 14 post surgery and treatment for further assessment. Heart specimens of the sacrificed rats were obtained. All the specimens were traced for DiI positive cells and their cardiomyogenic differentiation by immunohistochemical staining with specific antibodies for heart type troponin I (Santa Cruz) and PCNA (Dako). Specific secondary antibody conjugated with alkaline phosphatase (Santa Cruz) was used to visualize the positively stained cells. DiI positive signal was observed with a fluorescence microscope (Laica)
[0051] Estimation of Infarct Size:
[0052] Left ventricles from experimental rats sacrificed on day 14 were removed and sliced from apex to base in 3 transverse slices. The slices were fixed in formalin and embedded in paraffin. Sections (20 μm thickness) of the left ventricle were stained with Masson's trichrome, which labels collagen blue and myocardium red. These sections were digitized and all blue staining was quantified morphometrically. The volume of infarct (mm.sup.3) of a particular section was calculated based on the thickness of the slice. The volumes of infarcted tissue for all sections were added to yield the total volume of the infarct for each particular heart. All studies were performed by a blinded pathologist.
[0053] Angiogenic Assessment in Infarct Region:
[0054] Vascular density was determined on day 7 postinfarction from histology sections by counting the number of vessels within the infarct area using a light microscope under high power field (HPF) (×400). Six random and non-overlapping HPFs within the infarct filed were used for counting all newly formed vessels in each section of all experimental hearts. The number of vessels in each HPF is averaged and expressed as the number of vessels per HPF.
[0055] Assessment of regenerating cardiac myocytes and myocardia: The sections from both CMF pretreated MSCs-transplanted and non-treated MSCs-transplanted groups on day 7 post-ligation were stained with Ki67 or myosin heavy chain (WIC) antibodies to identify the regenerating myocardia. Specific secondary antibody conjugated with alkaline phosphatase was used to visualize the positive stains. Briefly, paraffin-embedded sections were microwaved in a 0.1 M EDTA buffer and stained with a polyclonal rabbit antibody with specificity against rat Ki67 at 1:3,000 dilution (Sant Cruz Biotechnology) and incubated overnight at 4° C. After they were washed, the sections were incubated with a goat anti-rabbit IgG secondary antibody conjugated with alkaline phosphatase at 1:200 dilution (Sigma) for 30 min, and the positive nuclei were visualized as dark blue with a 5-bromo-4-chloro-3-indolylphosphate-p-toluidine-nitro blue tetrazolium substrate kit (Dako). The immediate neighbor sections from corresponding paraffin tissue block were incubated overnight at 4° C. in a 1:50 dilution of rabbit anti-rat MHC (MF20, Developmental Hybridoma Bank, University of Iowa) antibodies, and further incubated for 30 minutes at room temperature in a 1:100 dilution of peroxidase-conjugated goat anti-rabbit IgG (Sigma). After incubation with 1 mg/mL diaminobenzidine (DAB; plus 0.02% H.sub.2O.sub.2), the slides were investigated by microscopic analysis. The regenerating myocardium area was delineated in the projected field by a grid containing 42 sampling points. Approximately, 30-60 calculating points along the border of a particular regenerating myocardium were selected in each section. This grid defined an uncompressed tissue area of 62,500 μm.sup.2, which was used to measure the selected 30-60 calculating points in each section. The shapes and volumes of regenerating myocardia in the central area of infarct were determined by measuring in each section (50 μm apart) of approximately 70 sections the shapes and areas occupied by the regenerating myocardia and section thickness. Integration and calculation with these variables produced a stereo-structure and yields the volume of a particular regenerating myocardium in the central area of the infarct in each section. Values and stereo structure of all sections of a particular tissue block were added and computed to obtain the total volume and the full stereo-structure of the regenerating myocardia.
[0056] Echocardiography Assessment of Myocardial Function:
[0057] Echocardiographic studies were performed using a Sequoia C256 System (Siemens Medical) with a 15-MHz linear array transducer. The chest of experimental rats was shaved, the animal was situated in the supine position on a warming pad, ECG limb electrodes were placed, and echocardiography was recorded under controlled anesthesia. Each experimental rat received a baseline echocardiography before the experimental procedure. Two-dimensional guided M-mode and two-dimensional (2D) echocardiography images were recorded from parasternal long- & short-axis views. Left ventricular (LV) end-systolic and end-diastolic dimensions, as well as systolic and diastolic wall thickness were measured from the M-mode tracings by using the leading-edge convention of the American Society of Echocardiography. LV end-diastolic (LVDA) and end-systolic (LVSA) areas were planimetered from the parasternal long axis and LV end-diastolic and end-systolic volumes (LVEDV and LVESV) were calculated by the M-mode method. LV ejection fraction (LVEF) and fractional shortening (FS) were derived from LV cross-sectional area in 2D short axis view: EF=[(LVEDV−LVESV)/LVEDV]×100% and FS=[(LVDA−LVSA)/LVDA]×100%. Standard formulae were used for echocardiographic calculations. All data were analyzed offline with software resident on the ultrasound system at the end of the study. All measured and calculated indexes were presented as the average of three to five consecutive measurements.
[0058] Statistics:
[0059] All morphometric data are collected blindly, and the code is broken at the end of the experiment. Results are presented as mean±SD computed from the average measurements obtained from each heart. Statistical significance for comparison between two measurements is determined using the unpaired two-tailed Student's t test. Values of P<0.05 are considered to be significant.
II. CMF-Induced Increased Survival Potential and Cardiogenic Differentiation of MSCs Ex Vivo
[0060] Referring to
III. Therapeutic Effect Via Transplantation of MSCs Pretreated with CMF
[0061] To determine whether the increased survival potential and cardiogenic differentiation efficiency showed ex vivo in MSCs treated with CMF prior to transplantation would bring about significant improvement in repairing of MI in vivo, or in other words, whether CMF's ex vivo effects have any therapeutic values, cell transplantation experiments with MI animal model were performed, where MSCs pre-treated with CMF were implanted in the areas of infarct. The homing, survival, proliferation, cardiomyogenic differentiation and maturation of the transplanted cells were traced by the positive signals of either Dil-florescence and by immunohistochemical staining for Ki67 and WIC in sections, which were from the hearts on day 7 and day 14 post infarction and cell transplantation. As shown in
[0062] Formation of new vessels could be detected as early as 12 hours after transplantation and many more newly formed vessels and capillaries filled with blood cells were observed in the whole infarct areas in the test group in 24 hours (before any regenerating cardiac myocytes could be seen) and in 7 days post infarction (
[0063] As shown in
TABLE-US-00001 TABLE 1 The distribution of ejection fraction (EF) and fractional shortening (FS). (mean ± _SE):¶ EF (%) FS (%) 2 days § 14 days 2 days § 14 days
Normal (16) 71.03 ± 4.05 68.24 ± 4.79 35.65 ± 3.99 34.02 ± 3.27 Sham (32) 70.45 ± 2.67 71.34 ± 2.77 36.03 ± 2.76 35.86 ± 2.13 CMF-pretreated (32) 59.79 ± 2.33* 67.13 ± 2.53* 29.43 ± 1.35* 31.72 ± 2.57* MSC control (32) 52.1 ± 2.54 53.3 ± 2.31 24.07 ± 1.47 23.49 ± 1.99 §, Sixteen rats for normal group and 32 rats for sham operated, CMF pretreated and MSC control groups respectively.
, Eight rats for normal group and 16 rats for sham operated, CMF-pretreated and MSC control gorups respectively,¶ *EP, P = 0.03 on day 2; P = 0.001 on day 14, and FS, P = 0.01 on day 2 and P = 0.002 on day 14.¶
indicates data missing or illegible when filed
IV. Direct Therapeutic Effects in MI Model without Pre-Treating MSCs and Transplantation
[0064] Referring to
[0065] Furthermore, echocardiography demonstrated that the replacement of infarcted heart tissue with structurally integrated regenerating myocardia and reconstituted vasculatures was accompanied by significant functional improvement by day 2 post-infarct in CMF-treated hearts, and further improvement by day 14 compared with control hearts, probably due to the growth and maturation of the regenerated myocardia and vasculatures that repaired the infarct.
V. Therapeutic Effect Via Conditioned Medium Induced by CMF-Treated MSCs
[0066] To determine whether conditioned medium containing certain induced proteins secreted by CMF-activated-MSCs would bring about similar effects as CMF direct application or transplantation of the CMF-pretreated-MSCs to the infarct area, the conditioned medium was tested with both MSCs culture and heart infarction animal model. Referring to
VI. Cellular Origin of the Regenerated Myocardia after Direct CMF Treatment
[0067] Referring to
VII. Manufacturing Pharmaceutical Compositions and their Uses in Treating Ischemic Heart Diseases in Mammals
[0068] Once the effective chemical compound is identified and partially or substantially pure preparations of the compound are obtained either by isolating the compound from natural resources such as plants or by chemical synthesis, various pharmaceutical compositions or formulations can be fabricated from partially or substantially pure compound using existing processes or future developed processes in the industry. Specific processes of making pharmaceutical formulations and dosage forms (including, but not limited to, tablet, capsule, injection, syrup) from chemical compounds are not part of the invention and people of ordinary skill in the art of the pharmaceutical industry are capable of applying one or more processes established in the industry to the practice of the present invention. Alternatively, people of ordinary skill in the art may modify the existing conventional processes to better suit the compounds of the present invention. For example, the patent or patent application databases provided at USPTO official website contain rich resources concerning making pharmaceutical formulations and products from effective chemical compounds. Another useful source of information is Handbook of Pharmaceutical Manufacturing Formulations, edited by Sarfaraz K. Niazi and sold by Culinary & Hospitality Industry Publications Services.
[0069] As used in the instant specification and claims, the term “plant extract” means a mixture of natural occurring compounds obtained from parts of a plant, where at least 10% of the total dried mass is unidentified compounds. In other words, a plant extract does not encompass an identified compound substantially purified from the plant. The term “pharmaceutical excipient” means an ingredient contained in a drug formulation that is not a medicinally active constituent. The term “an effective amount” refers to the amount that is sufficient to elicit a therapeutic effect on the treated subject. Effective amount will vary, as recognized by those skilled in the art, depending on the types of diseases treated, route of administration, excipient usage, and the possibility of co-usage with other therapeutic treatment. A person skilled in the art may determine an effective amount under a particular situation.
[0070] While there have been described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes, in the form and details of the embodiments illustrated, may be made by those skilled in the art without departing from the spirit of the invention. The invention is not limited by the embodiments described above which are presented as examples only but can be modified in various ways within the scope of protection defined by the appended patent claims.
REFERENCES
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