Alteration of plasma biochemical, haematological and ocular oxidative indices of alloxan induced diabetic rats by aqueous extract of Tridax procumbens Linn (Asteraceae)

Abstract

In this study, the effects of an aqueous extract of the leaves of Tridax procumbens on the haematology, plasma biochemistry and ocular indices of oxidative stress was investigated in alloxan induced diabetic rats. Diabetes mellitus was induced by injection of alloxan (80 mg/kg body weight), via the tail vein. The extract was administered orally at 100, 200 and 300 mg/kg (both to normal and diabetic rats), and metformin at 50 mg/kg. On gas chromatographic analysis of the alkaloid fraction of the aqueous extract, thirty nine known alkaloids were detected, consisting mainly of 73.91 % akuamidine, 22.33 % voacangine, 1.27 % echitamine, 0.55 % echitamidine, 0.36 % lupanine, 0.27 % crinamidine, 0.23 % augustamine and 0.10 % 6-hydroxypowelline. Tannic acid and β-sitosterol were detected in high quantities. Compared to Test control, the treatment dose-dependently, significantly lowered (P<0.05) plasma glucose, triglyceride, very low density lipoprotein cholesterol, total bilirubin, urea, blood urea nitrogen; plasma alkaline phosphatase, alanine and aspartate transaminases, and ocular superoxide dismutase activities, and lymphocyte count. It also significantly increased (P<0.05) plasma calcium and ocular ascorbic acid contents, haemoglobin concentration and neutrophil count. This study showed that the extract was hypoglycemic, positively affected the haemopoietic system and integrity and function (dose dependently) of the liver and kidney of the diabetic rats; improved the lipid profile and had no deleterious effect on red cell morphology and protected against oxidative stress in ocular tissues. This study also revealed the presence of pharmacologically active compounds in the leaf extract. All of these, highlight the cardioprotective potential of the leaves of Tridax procumbens, and support its use in traditional health care practices for the management of diabetes mellitus.