Characterization and Identification of Long-Chain and Short-Chain Phospholipid Oxidation Products by MALDI-MS~(n)

摘要

There is increasing evidence that phospholipid oxidation products play an important role in the pathogenesis of various diseases, including diabetes. As the major lipid constituents of cell membranes and lipoproteins, phospholipids have many functions in biological systems acting as fuels, signaling agents, or surfactants. In the nervous system, phospholipids are a main component of myelin, an electrically insulating material that forms around the axons of neurons. Following oxidative stress, many phospholipid oxidation products with varying structures and biological activities are formed. MS, coupled with soft-ionization techniques, is a key tool for elucidating structural changes resulting from oxidative stress. Two classes of phospholipid oxidation products are (1) long-chain products, formed by insertion of oxygen atom(s); and (2) short-chain products, formed by insertion of oxygen atom(s) and cleavage of the unsaturated fatty acid tail. This investigation characterizes long-chain and short-chain phospholipid oxidation products by matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-MS~(n)) utilizing a linear ion trap (LIT) mass analyzer. MS~(n) provides enhanced selectivity, resulting in more reliable identification of oxidized phospholipids.