Leaf Ethanolic Extract of Bauhinia monandra Increases Insulin Secretion in Rats Subjected to Intrauterine Malnutrition

Abstract

Aims: This work aimed to investigate the effects of Bauhinia monandra ethanolic extract (E) on blood glucose levels (G), insulin and lipids of control (C) and prenatal malnourished (M) rats. Samples: Animals (from 90 days) were on standard or isocaloric high glucose diet (67%, w/w) during 30 days. Study Design: Animals received 0.1% DMSO (2.5 ml/kg, po.) or E (500 mg/kg, po.). Glucose tolerance was evaluated in blood following glucose overload (1.5 g/kg, po.). Place and Duration of Study: Departamento de Bioquímica and Departamento de Fisiologia e Farmacologia, Universidade Federal de Pernambuco, between January 2006 and February 2007. Methodology: In acute tests, glucose tolerance and serum insulin were evaluated in C and M receiving DMSO or E. Lipids and hepatic enzymes were analyzed before DMSO or E application. Glucose was orally administered by gavage, for glucose tolerance; thirty minutes later, E or DMSO was given. Blood samples were collected for glucose and insulin measurements. In the chronic assay, glucose tolerance, lipids and hepatic enzymes were studied in groups C or M receiving DMSO or E. The group M receiving E had a diet rich in glucose (30 days). Glucose tolerance, lipids, and hepatic enzymes were evaluated before and after diet rich in glucose treatment with E. Serum insulin was measured by chemiluminescence; also, aspartate and alanine aminotransferases were analyzed after high dietary glucose. Serum total cholesterol and triglycerides were estimated with an auto analyzer. Results: In control rats, acute E administration reduced G, but did not change insulin secretion; in M rats, it induced insulin peak. In chronic study, animals on high glucose diet with E showed lower G; prenatal malnourished rats revealed higher insulin levels. Cholesterol, triglycerides and alanine aminotransferase did not change by intrauterine malnutrition or E.  Conclusion: Results indicated that E may act on beta-cells and stimulate insulin secretion.