10 - Autoxidation of Plasma Lipids, Generation of Bioactive Products, and Their Biological Relevance

Abstract

Plasma contains cholesteryl, glyceryl, and phosphoglyceryl esters of fatty acids as major lipid components. These compounds are carried in plasma and provide a source of metabolic fuel that drives all biochemical reactions required for normal cellular activity and they provide structural material for cell membranes and lipoproteins. These compounds also include molecules that signal receptor activation on the cell surface, triggering subsequent signaling cascades through various protein kinases and phospholipases. This chapter provides a brief summary of plasma lipid composition and the main chemical and biochemical methods of detecting and quantifying the major primary and secondary products of oxidation of plasma lipoproteins and presents a discussion of the physicochemical, chemical, and metabolic activities of the major individual molecular species or small groups thereof. It also provides attention to the possible involvement of oxo-lipids in metabolic syndromes and disease conditions, as well as prevention of oxidation. The nature and extent of plasma lipid autoxidation depends on the fatty acid composition of glycerolipids, glycerophospholipids, and cholesteryl esters of plasma lipo-proteins. The fatty acid composition of the lipoproteins varies with the diet and to a lesser extent with the age, sex, and general health of the individual.