The leaf and seed aqueous extract of Phyllanthus amarus improves insulin resistance diabetes in experimental animal studies

Ethnopharmacological relevance: Amongst the Yoruba tribe (Southwest Nigeria), water decoction of the leaf and seed of Phyllanthus amarus Schum. and Thonn. is reputably used for the local management of diabetes mellitus, obesity and hyperlipidemia. Aim of the study: The present study seeks to evaluate the effectiveness and elucidate mechanism(s) of action of the aqueous leaf and seed extract of Phyllanthus amarus (PAE) in normal and 10% sucrose-induced hyperglycemia and dyslipidemia as an experimental model of insulin resistance diabetes mellitus. Materials and methods: In this study, the repeated oral antihyperglycemic action of 150-600 mg/kg/day of PAE was evaluated in normal and 10% sucrose-induced insulin resistance rats using indicators such as fasting blood glucose (FBG), insulin and insulin resistance indices. The extract's weight losing, antihyperlipidemic and anti-atherogenic effects were also evaluated by measuring the effect of the extract on the body weight, plasma levels of triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c) and atherogenic indices. Results: In normal rats, PAE caused significant (p <0.05, p <0.01 and p <0.001) and dose related decreases in body weight, FBG, TG, TC, LDL-c, and atherogenic indices. Repeated oral treatment with 10% sucrose drink for 30 days was associated with significant (p <0.001) weight gain, hyperglycemia, insulin resistance indices, hyperlipidemia and atherogenic indices. However, pre-treatment with PAE significantly (p <0.05, p <0.01 and p <0.001) and dose-dependently attenuated increase in any of these measured parameters. Conclusions: Overall, results of this study showed PAE to effectively control insulin resistance DM which was mediated via improvement in insulin resistance, thus, validating its ethnomedical use in the local management of DM. (C) 2012 Elsevier Ireland Ltd. All rights reserved.