Carica Papaya Leaves Extract: an Antidote to Aluminium Chloride Induced Hippocampal Degeneration in the Brain of Wistar Rats

ABSTRACT Background: Aluminum chloride (AlCl₃) exposure is linked to neurotoxicity, causing oxidative stress, neuroinflammation, and hippocampal degeneration, which impair cognitive functions. This study investigates the protective effects of Carica papaya leaf extract (CPLE) against AlCl₃-induced hippocampal degeneration in Wistar rats. Methods: Twenty-five adult male rats were divided into five groups: Control, AlCl₃ only group (10 mg/kg body weight), AlCl₃ plus extract (10 mg/kg of AlCl₃ plus 200 mg/kg of Carica papaya leaf extract), Extract only group (200 mg/kg of Carica papaya leaf extract) and AlCl₃ with vitamin E (10 mg/kg of AlCl₃ plus 100 mg of vitamin E) for 21 days. Biochemical analyses revealed elevated oxidative stress markers, such as malondialdehyde (MDA), and reduced antioxidant enzymes, including Glutathione (GSH), Tumor necrosis Factor-Alpha (TNF), Cardiac Troponins (cTnl and cTnT), Superoxide dismutase (SOD), Blood Urea nitrogen (BUN) and catalase (CAT), in the AlCl₃ group. Results: Histopathological examination showed neuronal loss and structural disorganization in the hippocampus, while immunohistochemical analysis indicated increased pro-inflammatory cytokines (IL-6 and TNF-α). Treatment with CPLE, particularly at higher doses, significantly ameliorated these changes, improving cognitive performance, restoring antioxidant balance, and reducing neuroinflammation. Conclusion: These findings suggest that Carica papaya leaf extract has potent antioxidant and neuroprotective properties, effectively counteracting AlCl₃-induced hippocampal degeneration. CPLE shows promise as a natural therapeutic agent for aluminum-induced neurotoxicity, warranting further exploration.