The Effect of Rosmarinus officinalis L Extract on the Inhibition of High Glucose-Induced Neurotoxicity in PC12 Cells: an In Vitro Model of Diabetic Neuropathy

Abstract

Abstract Background and Aim: Diabetes mellitus and continued hyperglycemic condition prompt serious diabetic complications such as diabetic neuropathy. Numerous studies have shown the involvement of oxidative stress and high glucose-induced cell death in the progress of diabetic neuropathy. Rosmarinus officinalis L has been suggested in the literature as an anti-diabetic herbal medicine that contains potent antioxidant components. Therefore, the neuroprotective effect of Rosmarinus officinalis L (RE) extract was investigated in glucose-induced neurotoxicity via pheochromocytoma )PC12( cells as an appropriate in vitro model of diabetic neuropathy. Materials and Methods: Cell viability was determined using MTT assay. Cleave caspase-3 and Bax: Bcl2 ratio, as biochemical parameters of cellular apoptosis, were measured by western blotting analysis. Results: Our data showed that a 4-fold elevation in the glucose in the medium significantly reduced cell viability (P < 0.01) and increased caspase-3 activation (P < 0.01) as well as Bax: Bcl2 ratio (P < 0.05) in PC12 cells after 24 h. Incubation of high glucose medium cells with 60μg/ml RE extract decreased high glucose-induced cell toxicity and prevented caspase-3 activation and Bax: Bcl2 ratio. Conclusion: It could be concluded that RE extract is effective in the protection against hyperglycemia-induced cellular toxicity. This could be relevant to the prevention of apoptosis. Moreover, the results suggest that RE has the therapeutic potential to attenuate diabetes complications such as that neuropathy. Keywords: Rosmarinus officinalis, hyperglycemia, cell toxicity, apoptosis, diabetic neuropathy, PC12 cells