Phytochemical Screening, In vitro Antioxidant Capacity and Nephro-protective Effects of Combined Extract of Psidium guajava and Carica papaya Leaves in Rats Intoxicated with Cadmium

Aim: Toxic effects arising from heavy metals and other contaminants in the environment are presently been tackled by the use of medicinal plants. Thus, this study evaluated the protective effects of combined extract of Psidium guajava and Carica papaya leaves on kidney injury occasioned by cadmium (Cd) toxicity.

Materials and Methods: Phytochemical investigation of the combined extract revealed the presence of tannins, saponins, flavonoids, triterpene, steroids, alkaloids, cardiac glycoside, anthocyanins, and anthraquinone and the the extract displayed excellent antioxidant capacity in vitro. Eighteen adult female rats were divided into three groups: Group 1 (Control, received feed and water only); Group 2 (Cadmium, received single dose of cadmium, 30mg/kg body weight at the start of the experiment) and Group 3 (Cadmium + combined leaf extract, received cadmium as in group 2 above and 200mg/kg body weight of extract, daily for two weeks).

Results: Intoxication with Cd causes significantly (p<0.05) increased in the levels of lipid peroxidation and in the activity of glutathione peroxidase. Cd intoxication also depleted glutathione (GSH), super oxide dismutase (SOD) and catalase (CAT) reserves and brought about a significant increase in serum urea, creatinine, sodium and potassium. However a significant (p<0.05) normalization in the levels of GSH, SOD, CAT, urea, creatinine, sodium and potassium was observed in Cd-intoxicated rats administered the extracts as compared to the control (untreated rats).

Conclusion: The results reveal that Cd causes nephro-toxicities manifested via lipid peroxidation, increase in serum levels of urea, creatinine, sodium and potassium ions and that the combined extract of Psidium guajava and Carica papaya leaves possess adequate antioxidant power against Cd-induced nephro-toxic effects.