Stabilization of rat heart mitochondria by alpha-tocopherol in rats.

alpha-Tocopherol (alpha-T) acts by different mechanisms: scavenging free oxygen radicals (FOR) and stabilizing membranes; both may contribute to the prevention of the pathogenesis of diseases like cardiovascular events. The present work shows that alpha-T breaks the vicious cycle generated by damaged mitochondria. The latter stimulate the immune system increasing FOR formation that leads to more damaged mitochondria. alpha-T inhibits lipid peroxidation induced by recombinant human tumor necrosis factor (rh-TNF). Polymorphonuclear neutrophils (PMN) are activated by TNF to produce FOR causing lipid peroxidation of cardiomyocyte membranes. Since TNF is used as a therapeutic agent against certain tumors, treating patients with alpha-T could protect them against systemic side effects of TNF.