Glucose and Lipid Lowering Potentials of Heliotropium indicum L. Leaves in Alloxan-Induced Hyperglycaemic Rats

Abstract

The antidiabetic potentials of Heliotropium indicum L. leaf aqueous (HILA) extract used for the management of diabetes by Traditional Medicinal Practitioners (TMPs) in Nigeria was assessed. Alloxan (ALX)-induced hyperglycaemic rats were orally administered with known folkloric dosage of 30 and 75 mg/kg b. wt. of HILA extract, once a day, for 14 days. Fasting blood glucose (FBG) levels were monitored and pancreatic histology was examined. Net hepatic glycogen (GLY) concentration and lipid profiles were also determined. Prior to treatment, ALX-induced hyperglycaemia (>250 mg/dL) was established in rats. Oral administration of 30 and 75 mg/kg b. wt. HILA extract to diabetic rats for 14 days caused significant reduction in FBG to baseline values observed in non-diabetic conditions. Treatment with HILA extract also showed improvement in lipid abnormalities observed in hyperglycaemic condition, levels of triglyceride, total cholesterol and LDL-cholesterol were significantly reduced and HDL-cholesterol increased resulting in improved artherogenic index. Hepatic GLY concentration was significantly increased in diabetic rat treated with the extract. Histological examinations showed degenerated and sparse pancreatic islets β-cells in non-treated diabetic rat, whereas microscopy of treated rats showed mild to normal architecture with enriched β-cells. Preliminary phytochemical profiling of the extract revealed the presence of alkaloids (2.54 mg/g), saponins (0.28 mg/g), phenols (0.04 mg/g) and anthraquinones (0.01 mg/g). Results from this study revealed that the aqueous leaf extract of H. indicum possesses not only antihyperglycaemic, but also antidyslipidemic activities, that may prove to be of clinical importance in the management of diabetes and associated secondary complications.