Subchronic Toxicological Studies of Methanol and n-Hexane Extracts of Leptadenia hastata (pers) Decne Leaves Used as Antihypertensive Agent

Abstract

Leptadenia hastata leaf extracts are used in the folkloric treatment of hypertension and its attendant complications. Sub-chronic toxicological study of the methanol and n-hexane leaf extracts of L. hastata was carried out orally on Swiss albino rats for 28 days. Doses of 100, 300, and 600 mg kg^-1 bodyweights of both extracts were administered through the oral route once daily to the rats in respectively labeled test groups while the control group with normal saline (0.5 ml). L. hastata methanol extract showed a moderate presence of alkaloids (0.92±0.14) and cardiac glycosides. The LD₅₀ of both extracts is >5000 mg kg^-1 bodyweight. ALT, AST, ALP, and total protein were all significantly high in 600 mg kg^-1 bodyweight of the extract (n-hexane)-treated group by a 2% reduction in bodyweight on the 12th day. Lipids in both extract-treated groups were reduced with a concomitant increase in HDL of the methanol extract-treated groups and a decrease in the extract (n-hexane)-treated groups. PCV and RBC significantly increased (p<0.05) and decreased (p>0.05) in the methanol and n-hexane extract-treated groups respectively, while the WBC significantly increased in the extract (n-hexane)-treated groups. Only 600 mg kg^-1 bodyweight of the extract (n-hexane)-treated group showed a decrease in liver and kidney weights with an increase in the weight of the heart. Electrolytes were significantly reduced in 600 mg kg^-1 bodyweight of the extract (n-hexane)-treated group while urea, creatinine, direct, and total bilirubin increased in the extract (n-hexane)-treated groups. L. hastata extracts at 600 mg kg^-1 bodyweight may be toxic.