Context: Oxidative stress has been implicated in the progression of pathogenesis in diabetes mellitus and leads to a variety of deformations in the central nervous system. Recent studies have provided several insights on therapeutic uses of resveratrol in diabetic complications.
Objective: The present study determines if resveratrol ameliorates oxidative stress and molecular changes in the brain frontal cortex of streptozotocin-induced diabetic rats.
Materials and methods: Rats were divided into four groups: control, diabetic, resveratrol-treated control, and resveratrol-treated diabetic. After diabetes induction, resveratrol (20 mg/kg) was given intraperitoneally once daily for 4 weeks. In addition to enzymatic activities, gene and protein expression of brain antioxidant enzymes were utilized by qRT-PCR and Western blot, respectively.
Results: The results indicated a significant elevation in total oxidant species (1.22-fold) and malonedialdehyde (1.38-fold) contents in diabetic rat brain cortex tissues. In addition, significant augmentation in the activities of catalase (1.38-fold) and superoxide dismutase (3-fold) was witnessed with the gene and protein expression levels reflecting a transcriptional regulation. Resveratrol treatment significantly normalized diabetic malonedialdehyde and oxidized glutathione levels and strengthens the action of all antioxidant enzymes. Recovery of the diabetes-associated changes reflects the reduction of oxidative conditions by resveratrol and reveals the decrease in the requirement for the activation of antioxidant defense systems in the brain tissues of diabetic rats.
Discussion and conclusion: Potent antioxidant and neuroprotective properties of resveratrol against diabetes-induced oxidative damage were demonstrated and the results support the conduct of new studies searching for the molecular mechanism of diabetes-induced changes in brain tissues.
Keywords: Brain; diabetes mellitus; gene expression; oxidative stress; resveratrol.