Antioxidant and Nephroprotective Effects of Cassia occidentalis Leaves Methanolic Extract in Rats

Abstract

Cassia occidentalis (Sorib) is a rich source of bioactive compounds with a variety of pharmacological therapeutic properties and considerable effectiveness against oxidative stress-induced severe renal disease. In this study C. occidentalis leaves methanolic extract (COLM) was evaluated for its antioxidant and nephroprotective activities. The phytoconstituents of the leaves extract was also investigated. The antioxidant activity of the extract was measured using 1,1- diphenyl-2- picryl-hydrazyl (DPPH) radical scavenging assay. Nephroprotective activity of COLM was assessed using Wistar albino rats. Seventy rats were divided randomly into seven groups of ten rats each; control group, nephrotoxic group, rats were injected with gentamicin only at a dose of 80mg/kg, intraperitoneally (IP) for 8 days. Standard drug group, animals were injected with gentamicin (80 mg/kg IP), and at the same time they received standard drug silymarin at a dose of 100mg/kg orally for 8 days. Low and high doses of the plant groups, rats were injected with gentamicin (80mg/kg IP), with concurrent administration of C. occidentalis leaves methanolic extract at a dose of 200 or 400 mg/kg orally for 8 days. Toxicity groups, rats were given C. occidentalis leaves extract only at a dose of 200 or 400 mg/kg orally for 8 days. The levels of urea, creatinine, uric acid, and total protein in the blood were used to assess kidney function. Blood constituents, and relative kidney weight were also measured. Phytoconstituents of COLM comprise tannins, saponins, coumarins, and alkaloid as active components and devoid of flavonoids, and sterols. COLM exhibited moderate antioxidant activity (50 ± 0.04%) compared to the standard antioxidant agent propyl gallate (93 ± 0.01%) using DPPH radical scavenging assay. Administration of COLM at a dose of 200 and 400 mg/kg for 8 days significantly (P < 0.05) lowered the levels of urea compared to the gentamicin group. The levels of creatinine, uric acid and total protein were insignificantly changed (P > 0.05) at day 8 in treated groups compared with control. COLM showed no significant changes compared to the standard drug Silymarin. Relative weight of kidneys was significantly increased in treated groups, except toxicity groups, compared to that of control. The results concluded that the methanolic extract of C. occidentalis leaves might possess nephroprotective activity in rats. This effect may be due to antioxidant activity or the chemical constituents of the plant.