Resveratrol reduces excessive cholesterol accumulation in Goto-Kakizaki rat, a model with congenital type 2 diabetes

Resveratrol (3, 5, 3'-trihydroxystilbene) is a naturally-occurring, biologically active compound having numerous beneficial effects in the organism, including anti-diabetic properties. Its anti-diabetic action have been relatively well established using various animal models, however, in Goto-Kakizaki (GK) rats is poorly explored. These animals are non-obese and have a congenital type 2 diabetes. In the present study, effects of resveratrol on cholesterol content, blood levels of some hormones (thyroxine, triiodothyronine, ghrelin and spexin), glucose and parameters indirectly related with renal function (creatinine, urea nitrogen, total protein and albumin) were explored in GK rats. GK and control rats were treated with resveratrol for 10 weeks at the dose of 20 mg/kg body weight. It was shown that cholesterol content was significantly increased in the blood, liver and the skeletal muscle of diabetic rats, compared with the control animals. However, the resveratrol therapy was associated with a markedly reduced tissue cholesterol content. Our study also demonstrated that blood levels of thyroxine (T4) were decreased, and triiodothyronine (T3) increased in GK rats. These alterations were, however, not significantly affected by resveratrol. GK rats had elevated blood glucose levels, but hyperglycemia was not ameliorated by resveratrol. It was also shown that blood creatinine levels were increased in diabetic rats. However, in animals subjected to the resveratrol therapy, the blood creatinine level was unchanged. Concentrations of ghrelin, spexin and other blood parameters indirectly related with the renal function were shown to be similar in GK and control rats. These results indicate that resveratrol beneficially influences cholesterol concentrations in tissues of diabetic rats; however, it is ineffective in the case of thyroid hormones and glucose. Moreover, it was shown that resveratrol did not induce any significant effects in non-diabetic animals.