Memory impairment effect of Cannabidiol Oil and Prednisolone Treatment: Alteration of Neuro-oxidant markers and Acetylcholinesterase Activity in the Hippocampus of Cadmium-Induced Toxicity in Male Wistar Rats

Background: There have been conflicting reports on the effect of Cannabis products on learning and memory. Hence this study  investigated CBD oil's and prednisolone treatment's cognitive impact on cadmium-induced toxicity in male Wistar rats. Methods: Forty  rats weighing between 150g to 200g were assigned into 8 groups (1-8) of five animals each. Group A control, Group B-H received 1mg/kg body weight prednisolone; 1.5mg/kg Cadmium; 1mg/kg pred+0.2mg/kg CBD-oil; 0.2mg/kg CBDoil+2mg/kg cadmium; 3mg/kg  pred+2mg/kg cadmium; 0.1mg/kg CBD-oil and 0.2mg/kg CBD-oil respectively. The administration was done using gavage for 14 days. A  T-maze test apparatus was used to determine the latency of object recognition before and after administration. Results: There was a  significant decrease in latency of object recognition in prednisolone, cadmium, and 0.2mg/kg CBD-oil treated groups than control after  administration. Calcium ion significantly (P<0.05) increased in the cadmium+ 0.1mg/kg CBD-oil treated group and decreased in the  pred+CBD-oil group compared to the control. Acetylcholinesterase significantly (P<0.05) increased in prednisolone, pred+cadmium, and  0.2mg/kg CBD-oil treated groups and decreased in cadmium, pred.+CBD-oil, cadmium+CBD-oil, and 0.1mg/kg CBD-oil treated groups  compared to control. Catalase significantly increased in pred+cadmium, 0.1mg/kg CBD-oil, and 0.2mg/kg CBD-oil treated groups  compared to control. SOD significantly decreased in the treatment groups than the control. Malondialdehyde significantly increased in  cadmium, pred+CBD-oil, cadmium+CBD-oil, 0.1mg/kg CBD-oil, and 0.2mg/kg CBD-oil than control. Glutathione peroxidase significantly  decreased in treated groups compared to control. Reduced glutathione significantly decreased across treated groups than the control.  Histology of the hippocampus revealed visible pathologic changes in pred+cadmium, 0.1mg/kg CBD-oil, and 0.2mg/kg CBD-oil treated  groups with cellular vacuolization, Perivascular leucocyte infiltration, and pycnotic nuclei, indicating slight inflammation and detrimental  effects of the treatment in the histoarchitecture of the hippocampus. Conclusions: CBD oil, prednisolone, and cadmium administration at  different doses induced biochemical alterations, and exacerbated cognitive and neurobehavioral decline by enhancing oxidative  stress, acetylcholinesterase activity, and alteration in the cytoarchitecture of the hippocampus