Histological and Immunohistochemical Study of the Effect of Stevia Rebaudiana Extract on the Cerebral Cortex of High Fat Diet-fed Adult Male Albino Rat

Introduction: Obesity is a worldwide health challenge, related to many cognitive and neurodegenerative disorders. The high fat diet (HFD) is considered the main cause of obesity in humans and the standard method for its induction in laboratory animals. Stevia Rebaudiana, a non-caloric natural sweetener, is a promising agent in the management of many medical conditions due to its antioxidant, anti-apoptotic, anti-inflammatory, and hypolipidemic properties.Aim of the Work: To evaluate the effect of Stevia Rebaudiana extract on the cerebral cortex of high fat diet-fed adult male albino rats.Materials and Methods: 40 rats were distributed into 4 equal groups; Control group, Stevia-group (daily fed a standard balanced diet & received 400 mg/kg/day of Stevia Rebaudiana extract orally for consecutive 10 weeks), HFD-group (daily fed a HFD for consecutive 10 weeks), and HFD & stevia-group (daily fed a HFD concomitantly with Stevia Rebaudiana extract at similar dose and route as stevia group for consecutive 10 weeks). Specimens of the cerebral cortex were prepared for biochemical, histological, and immunohistochemical techniques.Results: The HFD-group exhibited a significant increment in (final body weight, weight gain percentage, serum TC, TGs & LDLc, and tissue MDA & MPO), and a significant decrement in (serum HDL and tissue CAT, GPx & SOD). Further, HFD-group exhibited remarkable histological alterations in the cerebral cortex and a significant increment in caspase-3, GFAP, and iNOS immunohistochemical-expression. Co-administration of Stevia Rebaudiana extract with high fat diet prevented most of these biochemical, histological and immunohistochemical alterations.Conclusion: The obtained results highlighted that Stevia Rebaudiana extract had a potent ameliorative effect versus the induced adverse effects of high fat diet on rats’ cerebral cortex.