Determination of acylglycerols from biological samples with chromatography-based methods

Lipids are the most diverse class of metabolites in mammalian physiology and dysregulation of lipid metabolism is linked to various diseases. Alterations in acylglycerols, a major class of lipids in plasma and adipose tissue, are involved in the pathogenesis of obesity and type 2 diabetes. Therefore, determination of acylglycerols is important to depict and unravel cellular mechanisms related to pathological outcomes, and specific molecular species of acylglycerols might be promising biomarker candidates. The variety of acylglycerols can be characterized in different ways. Enzymatic assays enable the determination of total tri- or diacylglycerols showing a possible relation to diseases, but they do not allow clarification of molecular mechanism. While gas chromatography can provide an overview of the fatty acid composition of total or separated lipids, a very detailed description of the individual molecular acylglycerol species is possible via liquid chromatography, particularly when combined with mass spectrometry. This review describes the determination of acylglycerols considering recent developments, with a focus on mammalian serum/plasma and tissue.