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

Abstract

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.

Resveratrol affects the lipid profile but not antioxidant enzymes gene expression in rats fed hypercholesterolaemic diet

“…Similar results were reported by Kim et al (2011) andCho et al (2012). Albeit not all studies confirm that RSV reduces body fat (Louis et al, 2011;Tauriainen et al, 2011).…”

Resveratrol reduces chronic inflammation and improves insulin action in the myocardium of high-fat diet-induced obeserats

“…The present study found similar results, that is, resveratrol supplementation increased IR, IRS1, and Akt phosphorylation in the myocardium and consequently, insulin sensitivity, as shown by the rate of glucose disappearance. Concordantly, resveratrol supplementation reduced hyperglycemia in an animal obesity model 25 .…”

“…An insulin tolerance test was performed at the end of the study period "0" (without insulin), 5,10,15,20,25, and 30 minutes after an intraperitoneal injection of insulin (2 U/kg). Body and epididymal adipose tissue were weighed.…”

“…Food was removed six hours before the test and the first blood collection corresponded to time "0" Next, insulin (2 U/kg of body weight) was injected intraperitoneally and blood samples were collected from a tail incision after 5,10,15,20,25 …”

Why research on resveratrol-mediated cardioprotection should not decelerate1This editorial was invited by the Editors.

“…These include the following: (i) hypertension (Liu et al 2005;Dolinsky et al 2009;Thandapilly et al 2010;Toklu et al 2010;Wojciechowski et al 2010;Chan et al 2011;Rimbaud et al 2011); (ii) obesity (Louis et al 2011;Qin et al 2012 (Barger et al 2008). There is also one study that reported cardioprotection in an animal model of heart failure (Tanno et al 2010).…”