Treatment with low-dose resveratrol reverses cardiac impairment in obese prone but not in obese resistant rats.

We hypothesized that a low-dose resveratrol will reverse cardiovascular abnormalities in rats fed a high-fat (HF) diet. Obese prone (OP) and obese resistant (OR) rats were fed an HF diet for 17 weeks; Sprague-Dawley rats fed laboratory chow served as control animals. During the last 5 weeks of study, treatment group received resveratrol daily by oral gavage at a dosage of 2.5 mg/kg body weight. Assessments included echocardiography, blood pressure, adiposity, glycemia, insulinemia, lipidemia, and inflammatory and oxidative stress markers. Body weight and adiposity were significantly higher in OP rats when compared to OR rats. Echocardiographic measurements showed prolonged isovolumic relaxation time in HF-fed OP and OR rats. Treatment with resveratrol significantly improved diastolic function in OP but not in OR rats without affecting adiposity. OP and OR rats had increased blood pressure which remained unchanged with treatment. OP rats had elevated fasting serum glucose and insulin, whereas OR rats had increased serum glucose and normal insulin concentrations. Resveratrol treatment significantly reduced serum glucose while increasing serum insulin in both OP and OR rats. Inflammatory and oxidative stress markers, serum triglycerides and low-density lipoprotein were higher in OP rats, which were significantly reduced with treatment. In conclusion, HF induced cardiac dysfunction in both OP and OR rats. Treatment reversed abnormalities in diastolic heart function associated with HF feeding in OP rats, but not in OR rats. The beneficial effects of resveratrol may be mediated through regression of hyperglycemia, oxidative stress and inflammation.