Free radicals during HIV infection

In HIV infected patients, the increase of the concentration of free radicals is related to: a depletion of protective system (glutathione peroxidase, superoxide dismutase, vitamin E, selenium...), and an increased production of free radicals (superoxide anion, hydrogen peroxide, hydroxil radical) consecutive to the activation of lymphocytes and phagocyting cells, the chronic inflammation, the increased polyinsatured fatty acids concentration and lipoperoxidation, and direct or indirect effect of several pathologic agents including Mycoplasma sp. This free radical excess could impair cell membranes and generate apoptosis, the main cause of lymphocytes CD4(+) depletion. After a brief review of the free radicals synthesis pathway, their potential deleterious effects and the protective systems, the role of free radicals in the pathogenesis of HIV infection are discussed in regard to data reported in the literature.