The effect of methanolic crude extract of ocimum gratisimum leaves on insulin resistance and glut-4 gene expression in monosodium glutamate induced obese rats

Abstract

Obesity is a complex chronic global disease affecting people worldwide across all ages, sexes, ethnicities and nationalities. It is accompanied by remodeling of adipocyte, insulin resistance (IR) and type 2 diabetes. The present study was aimed to determine the effect of methanolic crude extract of Ocimum gratisimum leaves on insulin resistance and GLUT-4 gene expression in Monosodium induced obese Rats. Phytochemical screening of the crude extract of Ocimum gratisimum leaves was carried out before the grouping of animals. The study was conducted using thirty 30 male Wistar rats weighing between 100.0 – 150.0 g. The animals were divided into five groups of six each; Normal control (NC) rats, Obese control (DC) rats, Obese rats treated with Ocimum gratissimum (OG) 100 mg/kg B.W (OG-100), Obese rats treated with OG 200 mg/kg B.W (OG-200), Obese rats treated with orlistat 50 mg/kg B.W (OR-50). Obesity was induced by oral administration of 8 mg/g MSG for 7 days and animals were treated with respective doses orally for 1 week. The phytochemical screening of the crude extract of Ocimum gratisimum leaves revealed the presence of saponins, tannins, flavonoids, glycosides and the results obtained after induction of obesity with MSG showed significant (P<0.05) increase in weight of the rats. After 1 week of treatment with the extract, the weight, non-fasting blood glucose (NFBG) and HOMA-IR level of the rats decreased significantly (P<0.05) when compared to obese control rats. In addition, the level of serum insulin was increased significantly in all groups while fold expression of GLUT-4 gene was increased significantly (P<0.05) in OG-200 only. In conclusion, the use of methanolic crude extract of Ocimum gratissimum leaves can be a therapy in the treatment of obesity due to its significant hypoglycemic, anti hyperlipidemic and insulin resistance lowering properties.