Effect of conjugated linoleic acids on hepatic oxidative stress and hepatic mitochondrial respiratory chain enzyme activities in type 2 diabetic rats

    XU Wen, HAI Chunª²Xu, YANG Chen, LI Jiaª²Lin, WANG Peng

    Department of Hygiene and Toxicology, School of Preventive Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To observe the effect of conjugated linoleic acids on hepatic oxidative stress and enzyme activities of hepatic mitochondrial respiratory chain in type 2 diabetic (DM2) rats. METHODS: Sixty rats were randomly divided into 3 groups: control group, diabetic (DM) group and conjugated linoleic acids (CLA) treatment group. DM2 rat model was induced by feeds of higher sugar, fat and cholesterol with the injection of streptozotocin. Blood glucose was determined by a blood glucose testing instrument and serum insulin by a radioimmunological method. The contents of malondialdehyde (MDA), reduced glutathione(GSH) and the activity of superoxide dismutase (SOD) and catalase (CAT) in hepatic tissues were tested by biochemical methods. The enzyme activities of hepatic mitochondrial respiratory chain were measured by Clark oxygen electrode. RESULTS: Compared with those in control group, the blood glucose, serum insulin and MDA in liver increased significantly (P<0.05) and GSH content, activities of SOD, and CAT as well as mitochondrial respiratory chain enzymes in the hepatic tissues decreased remarkably (P<0.05) in the DM group. In CLA treatment group, the indexes above ameliorated to different degree and these changes were in a doseª²dependent manner. CONCLUSION: CLA ameliorates the energy metabolism impairment of DM liver by suppressing the oxidative stress and improving the activity of enzymes in mitochondrial respiratory chain, and CLA has effective protection from the oxidative injury induced by DM. ......