The wonders of isoprostanoids in biological systems
Résumé
Isoprostanoids are low abundance lipids derived from non-enzymatic oxidation of polyunsaturated fatty acids (PUFA). Despite the concentration of these molecules to be low (picogram to milligram) in biological specimen, it appears to have fundamental roles especially when under oxidative stress. The two most evaluated isoprostanoids are those derived from arachidonic acid and docosahexaenoic acid, namely 15-F2t-Isoprostane and 4-F4t-Neuroprostane respectively. The former is renowned to be general biomarker of in vivo oxidative stress whilst the latter is more known to be a bioactive lipid mediator and oxidative stress biomarker related to specific neurological disorders.
Giving credit to the total synthesis of the standards and the development of mass spectrometry namely LC–MS/MS, measurement of other types of isoprostanoids has been possible. Insofar, we have discovered dihomo-isoprostanes from adrenic acid, new types of phytoprostanes from alpha-linolenic acid, and more recently phytoprostanes from gamma-linolenic acid and stearidonic acid. Over 10 years of investigation in cells, tissues from crabs, corals, rodents, and so forth, biological fluids from rodents and human, plants namely algae, nuts and seeds, the level of these isoprostanoids although low in concentration, become significant depending on the oxidative stress status, inflammation and pathophysiological process, as well as the existence of PUFA. In this presentation, the significance of some isoprostanoids found in biological systems will be discussed.