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Global metabolomic and isobaric tagging capillary liquid chromatography-tandem mass spectrometry approaches for uncovering pathway dysfunction in diabetic mouse aorta.

ABSTRACT: Despite the prevalence of diabetes and the global health risks it poses, the biochemical pathogenesis of diabetic complications remains poorly understood with few effective therapies. This study employs capillary liquid chromatography (capLC) and tandem mass spectrometry (MS/MS) in conjunction with both global metabolomics and isobaric tags specific to amines and carbonyls to probe aortic metabolic content in diabetic mice with hyperglycemia, hyperlipidemia, hypertension, and stenotic vascular damage. Using these combined techniques, metabolites well-characterized in diabetes as well as novel pathways were investigated. A total of 53,986 features were detected, 719 compounds were identified as having significant fold changes (thresholds ≥ 2 or ≤ 0.5), and 48 metabolic pathways were found to be altered with at least 2 metabolite hits in diabetic samples. Pathways related to carbonyl stress, carbohydrate metabolism, and amino acid metabolism showed the greatest number of metabolite changes. Three novel pathways with previously limited or undescribed roles in diabetic complications--vitamin B6, propanoate, and butanoate metabolism--were also shown to be altered in multiple points along the pathway. These discoveries support the theory that diabetic vascular complications arise from the interplay of a myriad of metabolic pathways in conjunction with oxidative and carbonyl stress, which may provide not only new and much needed biomarkers but also insights into novel therapeutic targets.

SUBMITTER: Filla LA

PROVIDER: S-EPMC4261973 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Isobaric protein-level labeling strategy for serum glycoprotein quantification analysis by liquid chromatography-tandem mass spectrometry.

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| S-EPMC3690282 | biostudies-literature

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| S-EPMC3759156 | biostudies-literature

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| S-EPMC8564867 | biostudies-literature

Accounting for an isobaric interference allows correct determination of folate vitamers in serum by isotope dilution-liquid chromatography-tandem MS.

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| S-EPMC5771954 | biostudies-literature

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| S-EPMC6236683 | biostudies-literature

Development of capillary liquid chromatography: A personal perspective.

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| S-EPMC5675780 | biostudies-other

Ocrelizumab quantitation by liquid chromatography-tandem mass spectrometry.

Project description:IntroductionOcrelizumab is a monoclonal anti-CD20 antibody approved for the treatment of multiple sclerosis (MS). The clinical value of therapeutic drug monitoring (TDM) for this antibody in treatment of MS is unknown, and an adequately specific and precise quantitation method for ocrelizumab in patient serum could facilitate investigation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based quantitation methods have been shown to have higher analytic specificity and precision than enzyme-linked immunosorbent assays.ObjectivesTo establish and validate an LC-MS/MS-based quantitation method for ocrelizumab.MethodsWe present an LC-MS/MS-based quantitation method using immunocapture purification followed by trypsinization and analysis by a triple quadrupole mass analyzer obtaining results within the same day.ResultsWe found that the ocrelizumab peptide GLEWVGAIYPGNGDTSYNQK (Q1/Q3 Quantifier ion: 723.683+/590.77 y112+ Qualifier ion: 723.683+/672.30 y122+) can be used for quantitation and thereby developed a method for quantifying ocrelizumab in human serum with a quantitation range of 1.56 to 200 µg/mL. The method was validated in accordance with EMA requirements in terms of selectivity, carry-over, lower limit of quantitation, calibration curve, accuracy, precision and matrix effect. Ocrelizumab serum concentrations were measured in three MS patients treated with ocrelizumab, immediately before and after ocrelizumab infusion, with additional sampling after 2, 4, 8 and 12 weeks. Measured serum concentrations of ocrelizumab showed expected values for both Cmax and drug half-life over the sampled time period.ConclusionWe have established a reliable quantitation method for serum ocrelizumab that can be applied in clinical studies, facilitating the evaluation of ocrelizumab TDM in MS.

| S-EPMC9334332 | biostudies-literature

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