Neuroprotective Effect of Carica papaya Leaf Extract against Aluminium Toxicity: An Experimental Study on Cognitive Dysfunction and Biochemical Alterations in Rats

Abstract:

Objective: To study the protective role of alcoholic leaf extract of Carica papaya in aluminium induced cognitive dysfunction and oxidative damage in albino rats and to explore the neuroprotective effect of Carica papaya represented by behaviour and memory tests. Methods: The study was carried out for a period of 42 days (6 weeks) in aluminium chloride induced model. Behavioural assessment is done using Rota rod apparatus and Elevated plus maze and biochemical parameters from brain homogenate like acetyl cholinesterase (AchE) activity, Total protein, Lipid peroxidation (MDA), Super oxide dismutase (SOD), Catalase, Glutathione Reductase (GR) were estimated. Male Wistar rats (30) were divided into 5 groups of 6 rats each. Group I received normal saline. Group II were administered orally with aluminium chloride (100 mg/kg). Group III received Rivastigmine 0.3 mg/kg body orally. Group IV and V were administered with alcoholic Carica papaya leaf extract 200 and 400 mg/kg along with aluminium chloride of 100 mg/kg orally after 1 hr interval. All the data was analysed using One-way ANOVA followed by Tukey’s multiple comparison test. Results: Administration of alcoholic Carica papaya leaf extract (200mg/kg and 400mg/kg) showed significant (P<0.001) increase in level of acetyl choline, significant (P<0.001) reduction of total protein and significant (P<0.001) increase in the level of SOD, Catalase and Glutathione reductase in a dose dependent manner when compared with positive control. positive control. Conclusion: This study demonstrates alcoholic Carica papaya leaf extract has a neuroprotective effect against aluminium induced behavioural changes.

Key words: Carica papaya, Neuroprotective, Alzheimer’s disease, Aluminium chloride.