Alteration of mitochondrial functions by lipid peroxidation and inhibition by biscoclaurine alkaloid

During investigation of the changes in mitochondrial function accompanying lipid peroxidation, it was found that a biscoclaurine alkaroid protected their functional changes. The results obtained were as follows: 1) Fe(2+) induces lipid peroxidation of isolated mitochondria, resulting in deterioration of oxidative phosphorylation. 2) This deterioration relates to alteration in ion compartmentation of the mitochondrial membrane and an increase in latent ATPase activity. 3) This deterioration by Fe(2+) in ion compartmentation of mitochondrial membrane is strongly protected by a biscoclaurine alkaloid, cepharanthine. 4) Cepharanthine also inhibits the mitochondrial. lipid peroxidation induced by Fe(2+). 5) The protective effect of cepharanthine against deterioration in mitochondrial functions caused by Fe(2+) depends on its inhibitive action on lipid peroxidation as well as on its membrane stabilizing action. 6) Cepharanthine inhibits the lipid peroxidation of soybean lecithine liposomes by (60)Co-irradiation. 7) The action of cepharanthine described above is common to head to head type of biscoclaurin alkaloids which have diether bonds.