Protective effect of grape seed and skin extract against high-fat diet-induced liver steatosis and zinc depletion in rat.

BACKGROUND: Obesity is a tremendous public health problem, characterized by ectopic deposition of fat into non-adipose tissues as liver generating an oxidative stress that could lead to steato-hepatitis. Grape seed and skin extract (GSSE) is a complex mixture of polyphenolics exhibiting robust antioxidative properties. AIM: We hypothesize that GSSE could protect the liver from fat-induced lipotoxicity and have a beneficial effect on liver function. METHODS: Hepatoprotective effect of GSSE was measured by using an experimental model of fat-induced rat liver steatosis. Male rats were fed a standard diet or a high-fat diet (HFD) during 6 weeks and treated or not with 500 mg/kg bw GSSE. Lipid deposition into the liver was assessed by triglyceride, cholesterol and phospholipid measurements. Fat-induced lipoperoxidation, carbonylation, depletion of glutathione and of antioxidant enzyme activities were used as oxidative stress markers with a special emphasis on transition metal distribution. RESULTS: HFD induced liver hypertrophy and inflammation as assessed by high liver transaminases. HFD also induced an oxidative stress characterized by increased lipid and protein oxidation, a drop in glutathione and antioxidant enzyme activities as glutathione peroxidase and superoxide dismutase and a drastic depletion in liver zinc. Importantly, GSSE prevented all the deleterious effects of HFD treatment. CONCLUSIONS: Data suggest that GSSE could be used as a safe preventive agent against fat-induced liver lipotoxicity which could also have potential applications in other non-alcoholic liver diseases.

Grape seed extract alleviates high-fat diet-induced obesity and heart dysfunction by preventing cardiac siderosis.

Obesity is a tremendous public health problem, characterized by ectopic accumulation of fat into non-adipose tissues, leading to oxidative stress and chronic inflammation, in which the heart is the most severely affected organ. We used an experimental model of high-fat-diet (HFD)-induced obesity to analyze the link between oxidative stress and heart dysfunction. We also studied the cardioprotective effect of a grape seed and skin extract (GSE). Exposure of rats to HFD during 45 days induced heart hypertrophy, inflammation as assessed by plasma CRP elevation and contractile dysfunction as revealed after ischemia/reperfusion of Langendorff-perfused hearts. HFD also induced cardiac steatosis and lipotoxicity, which are linked to an oxidative stress status, worsened by increased siderosis and resulting in Ca(2+) overload. Importantly, GSE alleviated all the deleterious effects of HFD treatment. These studies suggest that GSE is a safe anti-obesity and cardioprotective agent that should also find potential applications in other inflammatory damaging conditions as stroke.