Protective effect of 20(S)-ginsenoside Rg_3 against rat cortex mitochondrial injuries induced by cerebral ischemia / 中国药理学通报

ABSTRACT

Aim To study the mitochondria-protective effects of 20(S)-ginsenoside Rg_3 on focal cerebral ischemia injuries and its mechanism in rats.Methods Middle cerebral artery occlusion(MCAO) was used to induce focal cerebral ischemia model.After 24 h occlusion,cortex mitochondria was isolated and prepared for the measurement of membrane fluidity,swelling,phospholipid content,respiratory function,activities of mitochondrial respiratory enzymes and superoxide dismutase(SOD),contents of phospholipid,malondial dehyde(MDA) and Ca~(2+) to evaluate the function of mitochondrial.Results Focal cerebral ischemia resulted in severe neuronal mitochondrial injuries,which could be alleviated by iv 20(S)-ginsenoside Rg_3 5 mg?kg~(-1),10 mg?kg~(-1),and nimodipine 1.0 mg?kg~(-1).The swelling of mitochondria was ameliorated,the decomposability of membrane phospholipid was decreased,the membrane fluidity of mitochondria was increased.20(S)-ginsenoside Rg_3 also significantly inhibited the decrease in the activities of respiratory(enzymes) and SOD of mitochondrial,and the increase in MDA and Ca~(2+) levels caused by cerebral ischemia in rats.Conclusion 20(S)-ginsenoside Rg_3 showed a protective action against the cortex mitochondrial injuries in rats induced by cerebral ischemia.The mechanisms may be derived from reducing lipid peroxides,inhibiting Ca~(2+) overload,scavenging free radicals and improving the energy metabolism.