The effect of resveratrol on leptin and sirtuin levels of kidney tissue of diabetic rats

Aim: In this study, our aim was to show the changes of histopathological effects of RSV and its impact on distributions of leptin and sirtuin proteins in kidney tissues of the rats made diabetic by using streptozotocin.Method: This study was carried 33 young, healthy, Wistar Albino female rats. The rats induced diabetic by giving STZ with a dose of 50 mg/kg were given RSV with the amount of 10 mg/kg for 15 days after chronic diabetes occurred. At the end of the six weeks, all rats were sacrificed under anesthesia. One of the kidney tissues was used for histologic (H & E and PAS) and immunohistochemical (leptin and sirtuin-2) studies and the other one was used for the western blot study (leptin and sirtuin-1) for every rat and both of them were passed through various processes. The results obtained from Western blot study was analyzed with Image J program and the other results were analyzed by SPSS program with Mann Whitney U and Kruskal-Wallis tests.Results: Blood glucose levels increased and weight levels decreased in the rats which were made diabetic. It is observed a slight decrease in blood glucose level in the RSV given diabetic group compared to the other diabetic group; however, this finding was not statistically significant. It was seen from the histopathological findings that renal damage in diabetic kidney decreased with RSV treatment. It was found from the immunohistochemical findings that leptin levels in diabetic kidney increased. The effect of RSV treatment on the levels of SIRT-2 did not differ between the groups. Findings of the Leptin was similar with the findings of the IHC based on the results of Western blot. It was found that the amount of Leptin in the diabetic kidney increased compared to the other groups. It was found that SIRT-1 significantly increased in DM + RSV group compared to other groups based on the Western blot analysis different than IHC findings.Conclusions: In conclusion, RSV causes changes of leptin and sirtuin levels in diabetic kidney. However, the mechanism of this effect is not clear. It is obvious that RSV has an important antioxidative and antidiabetic functionalities on prevention from kidney damage caused by increased oxidative stress in diabetes involving prolonged hyperglycemia. This may indicate that the effects of RSV may appear on leptin and sirtuin and this situation has a potential to develop new diagnostic and therapeutic strategies.Key words: Resveratrol, diabet, diabetic nephropathy, leptin, sirtuin.91