[Lipid peroxidation and free radicals. Role in cellular biology and pathology].

Membrane phospholipids attack by oxygen free radicals, i.e. lipidoperoxidation, occurs in normal cellular life. This free radicals attack is controlled by a protective system, both enzymatic (superoxide dismutase, catalase, glutahione peroxidase) and non enzymatic (vitamine E). Imbalance between attack and defense can explain many pathological events. In these events, the oxidation products of unsaturated fatty acids are of fundamental importance, in particular those derived from arachidonic acid (prostaglandins, prostacyclins, thromboxanes and leukotrienes).