A method of attenuating, treating or preventing cognitive aging in an individual who does not have dementia includes administering to the individual a therapeutically effective amount of a composition containing an omega-3 fatty acid, a nitric oxide releasing compound, Vitamin B12 and choline. The composition is administered in a daily dose that provides 0.1 to 50 times the recommended daily requirement (RDA) of Vitamin B12 per day, more preferably 0.1 to 40 times the recommended daily requirement (RDA) of Vitamin B12 per day and 0.01 to 10.0 times the recommended daily requirement (RDA) of choline. Optionally Vitamin B6 and/or Vitamin B9 can be included in the composition. The method can achieve a benefit that is one or more of decreasing brain atrophy, increasing or maintaining number of synapses, increasing amyloid-β phagocytosis, or decreasing or maintaining neuroinflammation in the non-demented individual. The method can prevent dementia in an individual at risk thereof, for example an elderly human.

A method for identifying pre-disposition to cognitive decline in a subject, the method comprising determining levels of: (a) omega-3 fatty acids, and vitamin D or a metabolite thereof; (b) omega-3 fatty acids, and homocysteine; (c) vitamin D or a metabolite thereof, and homocysteine; or (d) omega-3 fatty acids, vitamin D or a metabolite thereof, and homocysteine, independently in one or more samples obtained from the subject.

A method for identifying pre-disposition to cognitive decline in a subject, the method comprising determining levels of: (a) omega-3 fatty acids, and vitamin D or a metabolite thereof; (b) omega-3 fatty acids, and homocysteine; (c) vitamin D or a metabolite thereof, and homocysteine; or (d) omega-3 fatty acids, vitamin D or a metabolite thereof, and homocysteine, independently in one or more samples obtained from the subject.

A method of processing of a biological sample containing multiple metabolites is described The method comprising the steps of pre-treating the biological sample with a metabolite extraction solvent to provide a pre-treated sample, separating a first aliquot of the pretreated sample by reverse phase liquid chromatography (RPLC) to provide a first eluent containing resolved hydrophobic metabolites, and separating a second aliquot of the pre-treated sample by hydrophilic interaction liquid interaction chromatography (HILIC) to provide a second eluent containing resolved hydrophilic metabolites. The first and second eluents are assayed using targeted tandem mass spectroscopy operated in multiple reaction monitoring mode. Each liquid chromatography step (LC) is directly hyphenated with the tandem mass spectrometry (MS/MS) into a single LC-MS/MS analysis. The extraction solvent typically comprises methanol, isopropanol and an acetate buffer.

A method of processing of a biological sample containing multiple metabolites is described The method comprising the steps of pre-treating the biological sample with a metabolite extraction solvent to provide a pre-treated sample, separating a first aliquot of the pretreated sample by reverse phase liquid chromatography (RPLC) to provide a first eluent containing resolved hydrophobic metabolites, and separating a second aliquot of the pre-treated sample by hydrophilic interaction liquid interaction chromatography (HILIC) to provide a second eluent containing resolved hydrophilic metabolites. The first and second eluents are assayed using targeted tandem mass spectroscopy operated in multiple reaction monitoring mode. Each liquid chromatography step (LC) is directly hyphenated with the tandem mass spectrometry (MS/MS) into a single LC-MS/MS analysis. The extraction solvent typically comprises methanol, isopropanol and an acetate buffer.

A method for assessing a suicidal severity in a depressed patient according to an embodiment includes measuring a concentration of a suicidal behavior prediction biomarker contained in a biological sample of the depressed patient, wherein the suicidal behavior prediction biomarker is one or more markers selected from the group consisting of cortisol, interleukin-1 beta (IL-1β), homocysteine, total cholesterol, and folate, and determining a probability of an increased suicidal severity by comparing the measured concentration of the suicidal behavior prediction biomarker with a preset cutoff level thereof.

A method for assessing a suicidal severity in a depressed patient according to an embodiment includes measuring a concentration of a suicidal behavior prediction biomarker contained in a biological sample of the depressed patient, wherein the suicidal behavior prediction biomarker is one or more markers selected from the group consisting of cortisol, interleukin-1 beta (IL-1β), homocysteine, total cholesterol, and folate, and determining a probability of an increased suicidal severity by comparing the measured concentration of the suicidal behavior prediction biomarker with a preset cutoff level thereof.

Use of a folate derivative to assay in vitro the folate in a sample such as a biological sample.

Use of a folate derivative to assay in vitro the folate in a sample such as a biological sample.

Methods are described for measuring the amount of one or more of vitamin A, α-tocopherol, and the combination of β-tocopherol and γ-tocopherol in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying one or more of vitamin A, α-tocopherol, and the combination of β-tocopherol and γ-tocopherol in a sample.