Protection of mitochondrial system by Hippophae rhamnoides L. against radiation-induced oxidative damage in mice

The whole extract of the fresh berries of Hippophae rhamnoides L. (RH-3), which has been reported to provide protection to whole mice, various tissues, cells and cell organelles against lethal irradiation was further investigated for its effects on mitochondria isolated from mouse liver. Superoxide anion, reduced (GSH) and oxidized glutathione (GSSG) levels, NADH-ubiquinone oxidoreductase (complex 1). NADH-cytochrome c oxidoreductase (complex I/II), succinate-cytochrome c oxidoreductase (complex II/III), mitochondrial membrane potential (MMP), lipid pefoxidation (LPx) and protein oxidation (PO) were determined for RH-3-mediated radioprotective manifestation. Pre-irradiation treatment of mice with RH-3 (30 mg kg(-1), i.p.; single dose; -30 min) significantly inhibited the radiation-induced increase in superoxide anions, GSSG, thiobarbituric acid reactive substances (TEARS), complex 1, complex I/III activity and MMP maximally at 4 h (P< 0.05). This treatment inhibited the oxidation of proteins (P< 0.05) at all the time periods studied here. This study suggests that pre-irradiation treatment of mice with RH-3 protects the functional integrity of mitochondria from radiation-induced oxidative stress.