Neuroprotective effect of peanut against oxidative stress in streptozotocin-induced diabetic rats

ABSTRACT Diabetes mellitus is characterized by structural abnormalities, oxidative stress and neuroinflammation. This study aimed to determine the antioxidative therapeutic effects of peanut supplementation in improving brain damage resulted from streptozotocin (STZ)-induced diabetes. Forty male Wistar albino rats (Rattus novergicus) were categorized into four groups: control, peanut-supplemented, diabetic, diabetic and peanut-supplemented. The brain was dissected and subjected to biochemical analyses which indicated the role of diabetes in downregulating the expression of superoxide dismutase (SOD), dopamine (DA), serotonin (5-HT), adenosine triphosphate (ATP) and upregulating the levels of malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), 5-lipoxygenase (5-lOX), 8-hydroxy-deoxy guanosine (8-OHdG), Amyloid-β, α-amylase and tau protein expression levels. peanut treatment enhanced the diabetic-dependent brain histopathological features in the cerebrum and hippocampus, the immunohistochemical localization indicated significant downregulation at the expression of synaptophysin and caspase 3. Peanut supplementation significantly downregulated the gene expression of BAX, SOD, Myloperoxidase (MPO), Tumor necrosis factor- α (TNF-α), peroxisome proliferator-activated receptors (PPAR-α and PPAR-γ) and upregulated glial fibrillary acidic protein (GFAP) expression. In conclusion, peanut supplementation showed therapeutic potential against brain damage induced by diabetes. Peanut treatment significantly protected the brain from diabetic-related oxidative stress, and increased dopamine and serotonin levels by restoring the redox balance. Graphical Abstract