Two faces of lipid peroxidation products: the -Yin and Yang- principles of oxidative stress

Zhi-Hua Chen, Etsuo Niki

Abstract
Oxidants and antioxidants, like many other things, have two faces. Lipids, important biological substances of aerobic organisms, are oxidized by reactive oxygen and nitrogen species formed inevitably in vivo to give diverse products. The emerging evidence suggests that lipid peroxidation products have also two faces.
Lipid peroxidation products alter biological membrane organization and modify proteins and nucleic acids, which result in a number of dysfunctional states in vivo. Many studies show that the levels of lipid peroxidation products increase with the development of acute and chronic diseases. Lipid peroxidation products may modulate signal transduction pathways and mediate biological processes through receptors or receptor-independent pathways. At the same time, it has been shown that the lipid peroxidation products induce adaptive response and increase tolerance against forthcoming oxidative stress by upregulating defense capacity.
In this brief review, the examples of such dual opposite effects of lipid peroxidation products are shown and the underlying mechanisms are suggested.

Key words: Adaptive response; Antioxidants; Lipid peroxidation; Oxidative stress