Vitamin D Metabolism and Profiling in Veterinary Species

• Published in: Metabolites Vol. 10; no. 9; p. 371
• Main Authors: Hurst, Emma A, Homer, Natalie Z, Mellanby, Richard J
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 15.09.2020; MDPI AG
• Subjects: 1,25-dihydroxyvitamin-D; 24,25-dihydroxyvitamin-D; 25-hydroxyvitamin-D; C3-epimers; free vitamin D; Review; vitamin D; 1,25-dihydroxyvitamin-D; LC-MS/MS; 24,25-dihydroxyvitamin-D; C3-epimers; profiling; free vitamin D; vitamin D; comparative; 25-hydroxyvitamin-D; veterinary
• ISSN: 2218-1989; 2218-1989
• DOI: 10.3390/metabo10090371

The demand for vitamin D analysis in veterinary species is increasing with the growing knowledge of the extra-skeletal role vitamin D plays in health and disease. The circulating 25-hydroxyvitamin-D (25(OH)D) metabolite is used to assess vitamin D status, and the benefits of analysing other metabolites in the complex vitamin D pathway are being discovered in humans. Profiling of the vitamin D pathway by liquid chromatography tandem mass spectrometry (LC-MS/MS) facilitates simultaneous analysis of multiple metabolites in a single sample and over wide dynamic ranges, and this method is now considered the gold-standard for quantifying vitamin D metabolites. However, very few studies report using LC-MS/MS for the analysis of vitamin D metabolites in veterinary species. Given the complexity of the vitamin D pathway and the similarities in the roles of vitamin D in health and disease between humans and companion animals, there is a clear need to establish a comprehensive, reliable method for veterinary analysis that is comparable to that used in human clinical practice. In this review, we highlight the differences in vitamin D metabolism between veterinary species and the benefits of measuring vitamin D metabolites beyond 25(OH)D. Finally, we discuss the analytical challenges in profiling vitamin D in veterinary species with a focus on LC-MS/MS methods.