The effect of berberine chloride on oxidative stress in hippocampus of streptozotocin-diabetic rats

Diabetes mellitus increases the risk of central nervous system (CNS) disorders such as stroke, seizures, dementia, and cognitive impairment. Berberine, a natural isoquinolne alkaloid, is reported to exhibit beneficial effect in various neurodegenerative and neuropsychiatric disorders. Hyperglycemia through Enzymatic and non-enzymatic processes induces glucose spontaneous oxidation and by stimulating the production of active oxygen and nitrogen lead to oxidative stress. Also overproduction of ROS can cause to DNA and proteins damage and affected function of receptors, enzymes, transport proteins, and inactive antioxidant defense system enzymes or enzymes involved in the repair. In this study, the male wistar rats (n = 90) were randomly allocated into five groups: control, control berberine-treated (100 mg/kg), diabetic, berberine-treated diabetic (50, 100 mg/kg) groups. Diabetes was induced intraperinoneally STZ administration at the dose of 60mg/kg. Berberine was orally administered at doses of 50 and 100 mg/kg/day one week after STZ injection for a period of 8 weeks. Blood samples were taken from the tail vein 2, 4, 6, 8 weeks after STZ injection to measure blood glucose levels. Lipid peroxidation, nitrite levels and superoxid dismutase activity were evaluated as biomarkers of oxidative stress. Data were analyzed by using Prism-5, one way ANOVA and Tukey tests. Eight weeks after diabetes induction we observed an increase in lipid peroxidation, decreased superoxide dismutase activity, and elevated nitrite levels in the hippocampus of STZ-diabetic rats relative to levels in the control brains. In contrast, chronic treatment with berberine (50 and 100 mg/kg, p.o., once daily) lowered hyperglycemia, oxidative stress, and prevents the up regulation of GFAP in brain of diabetic rats. the present study demonstrates treatment with berberine resulted in an obvious reduction of oxidative stress in hippocampus of STZ -induced diabetic rats