[Free radicals derived from oxygen and lipid peroxidation. Role in cellular biology and physiopathology]

Lipid peroxidation results from the attack of membrane phospholipids by free radicals derived from oxygen. It plays a major role in normal cell life processes. Under physiological conditions, this attack is modulated by an enzymatic system (superoxide dismutase, catalase, glutathione peroxidase) and by a non-enzymatic system (vitamin E and others). Many pathological processes might be explained by a deficient protection system or by an imbalance between attack and protection. Lipid peroxidation is difficult to detect and measure, and the methods available still have low sensitivity.