lipidome

The lipidome refers to the complete set of lipids present in a cell, tissue, organism, or other biological system at a given time. It includes all lipid species such as glycerophospholipids, sphingolipids, sterols, glycerolipids, and fatty acyls, as well as related lipid classes. The lipidome is dynamic, reflecting developmental stage, diet, metabolic state, disease, and environmental factors.

Lipidome composition is highly diverse, with variations in head groups, backbones, and fatty acyl chain length and saturation. Lipids perform structural roles in membranes, store energy, and participate in signaling and regulation. Because lipids are hydrophobic and heterogeneous, their analysis poses unique challenges.

Lipidomics uses mass spectrometry and chromatography to identify and quantify lipid species. Approaches can be targeted or untargeted. Sample preparation and extraction methods such as Bligh-Dyer or Folch are commonly used. Data interpretation relies on lipid databases (e.g., LIPID MAPS) for annotation; compound isomerism and isobaric species complicate identification.

Applications of lipidomics include studying metabolism, nutrition, development, aging, and disease, as well as biomarker discovery and pharmacology. Limitations include incomplete coverage of the lipidome, isomer differentiation, variable instrument sensitivity, and the need for standardized reporting.