Effect of Ethanolic Extract of a Herbal Mixture, AjuMbaise, on the Histomorphology of the Hippocampus and the Hypothalamus of Adult Wistar Rats Exposed to High-Fat Diet

High fat diet (HFD) has been reported to cause oxidative stress and brain damage. Reports show that a herbal mixture, AjuMbaise, is rich in phytonutrients with vast medicinal values. The study investigated the effects of ethanolic extract of a herbal mixture, AjuMbaise, on the histomorphology of the limbic system of adult Wistar rats exposed to HFD. Fresh samples of AjuMbaise procured from Afor-Enyiogugu Market, Amuzi, Aboh-Mbaise L.G.A., of Imo State, Nigeria were air-dried, blended and macerated in 95% ethanol for 72hours. The extract was concentrated and stored in an air-tight container in a refrigerator. Twenty-five Wistar rats were divided into 5 groups, 1-5 (n=5) each. Group 1 received normal saline, group 2 received HFD and normal saline, while groups 4, 5 and 6 received HFD and 200mg/kg, 400mg/kg and 800mg/kg of the herbal mixture, respectively for 49days. All groups received feed and water ad libitum. On day 50, the rats were anaesthetized with 50 mg/kg thiopental sodium and aortic perfusion fixation with 4% paraformaldehyde was carried out. The brains were dissected out and the hippocampus and hypothalamus were harvested, fixed in Bouin‟s fluid and processed for Nissl stain. Group 2 showed hippocampal atrophy and neuronal degenerations in the hypothalamus while groups 3, 4 and 5 showed progressive recovery from the hippocampal and hypothalamic degenerations. The results show that ethanolic extract of the herbal mixture, AjuMbaise, can reverse the deleterious effect of HFD on the Hippocampus and the Hypothalamus in a dose dependent manner.