Evaluation of antidiabetic potential of Gymnema sylvestre

Abstract

Diabetes is a metabolic disorder categorized by insulin resistance and hyperglycemia, newlineresulting in diminished glucose uptake. Traditionally, numerous plant species have been newlineused as natural therapies for diabetes treatment Amongst these Gymnema sylvestre, a newlineknown antidiabetic medicinal plant is well established in Indian traditional system newline Ayurveda . A triterpene glycoside fraction (TG) isolated and purified from ethanolic newlineextract of Gymnema sylvestre (EEGS) was investigated for blood glucose control using in newlinevitro, in silico and in vivo methods. TG was characterized to be a mixture of triterpene newlineglycosides; gymnemic acid I, IV, VII and gymnemagenin. The purified fraction (TG) newlineexhibited effective inhibition of and#945;-glucosidases and pancreatic and#945;-amylase activities newlinerespectively compared to control. The in vitro studies were validated in silico to explain newlinethe activity order of triterpene glycosides (TG); gymnemic acid I, IV, VII and newlinegymnemagenin against selected enzyme targets. The results suggested tha t TG exhibited newlinestrong binding towards the dissacharidase enzyme targets. In vitro cell culture studies newlinewere performed using mouse pancreatic and#946;-cell lines (MIN6), mouse adipocytes (3T3L1) newlineand mouse skeletal muscle (C2C12) cell line models. TG showed negligi ble toxicity on newlineall the selected cell line models even at the highest concentration studied. There was an newlineincrease in glucose stimulated insulin secretion in a dose -dependent manner relative to newlinestandard antidiabetic drug glibenclamide. TG could also dose-dependently enhance the newlineexpression of glut-4, ppar-and#947;, adiponectin and leptin, thereby indicating potential newlineantidiabetic activity. We also attempted to encapsulate the active fraction (TG) to further newlineenhance the antidiabetic potential in vitro. We observed improvement in the glucose newlineuptake and increased levels of GLUT-4 (glucose transporter) in 3T3L1 cells. Further, o