Ameliorative Effect of Ashwagandha (Withania somnifera) Root Extract on Brain Oxidative Stress and Depression of Diabetic Rats

Abstract

Evaluation of the efficacy of ashwagandha root extract to ameliorate the oxidative stress and depression resulting from diabetes in male rats was conducted in the current study. Thirty-six male albino rats were randomly grouped into two main groups: normal (n=18) and diabetic (n=18), diabetes was induced by a single dose of 150 mg/kg BW alloxan injected intraperitoneally. After six weeks, both normal and diabetic groups were further subdivided into six sub-groups; normal control, 100 & 200 mg/kg BW ashwagandha treated normal, diabetic control, 100 and 200 mg/kg BW ashwagandha treated diabetic groups, for another six weeks. The forced swim test was used to assess depression, and serum serotonin levels were measured. In brain tissue homogenates, the glutathione reduced content, superoxide dismutase, and catalase activity were measured, as well as the total antioxidant capacity, total oxidative capacity, and malondialdehyde levels. Moreover, histopathological examination of the brain (cerebral cortex and cerebellum) were conducted. The obtained results revealed that the administration of ashwagandha extract to diabetic rats reduced immobility time during the forced swim test while increasing the serotonin levels significantly when compared with the diabetic group. Similar to this, brain total antioxidant capacity, glutathione reduced content, superoxide dismutase, and catalase activity increased significantly, while brain total oxidative capacity, oxidative stress index, and malondialdehyde levels decreased significantly when compared with the diabetic group. Furthermore, the histopathological changes in brain sections were reversed by ashwagandha root extract. In conclusion, ashwagandha root extract can be used to ameliorate the brain oxidative stress and depression brought on by diabetes mellitus at doses of 100 and 200 mg/kg BW.