Resveratrol Attenuates Benzo(a)pyrene-Induced Dysfunctions, Oxidative Stress and Apoptosis in Pancreatic Beta-Cells

Background: Diabetes mellitus is one of the major health problems for people all over the world today. According to international diabetes federation reports, diabetes affects 382 million people worldwide. Environmental pollutants have deleterious effects on glucose metabolism and cause insulin resistance. We aimed to investigate the effects of the environmental pollutants benzo(a)pyrene, and the therapeutic potential of resveratrol. Methods: 20 μM of benzo(a)pyrene was administered after 48 h of resveratrol (80 μM) application for 24 h in INS-1 (832/13) insulinoma cells. The cells were treated with 20 μM benzo(a)pyrene for 24 hours after 48 hours initial preconditions with 10 μM resveratrol. Oxidative stress status, insulin secretion and apoptosis were analyzed by molecular techniques. Results: Though resveratrol increased the antioxidant status which was decreased by benzo(a)pyrene, interestingly, it increased the oxidative status. Resveratrol increased benzo(a)pyrene-depleted reduced glutathione levels to the control level. The mRNA expression levels of beta-cell functions associated with genes insulin-1, insulin-2 and sirtuin-1 were upregulated by resveratrol. Resveratrol treatment elevated the insulin concentration of culture medium, and the mRNA expression of forkhead box protein-1 gene. Resveratrol upregulated benzo(a)pyrene-downregulated p53 gene expression. On the other hand, benzo(a)pyrene-downregulated mRNA expression of B-cell lymphoma-2 was induced by resveratrol treatment. Conclusion: The data showed that resveratrol could reverse the oxidative alterations, functional impairments and the carcinogenetic effects of benzo(a)pyrene in pancreas beta-cells.