Methanolic extract of Momordica cymbalaria enhances glucose uptake in L6 myotubes in vitro by up-regulating PPAR-γ and GLUT-4

The present study was undertaken to evaluate the influence of the methanolic fruit extract of Momordica cymbalaria(MFMC) on PPAR(Peroxisome Proliferator Activated Receptor gamma) and GLUT-4(Glucose transporter-4) with respect to glucose transport.Various concentrations of MFMC ranging from 62.5 to 500 gmL-1 were evaluated for glucose uptake activity in vitro using L6 myotubes,rosiglitazone was used as a reference standard.The MFMC showed significant and dose-dependent increase in glucose uptake at the tested concentrations,further,the glucose uptake activity of MFMC(500 gmL-1) was comparable with rosigilitazone.Furthermore,MFMC has shown up-regulation of GLUT-4 and PPAR gene expressions in L6 myotubes.In addition,the MFMC when incubated along with cycloheximide(CHX),which is a protein synthesis inhibitor,has shown complete blockade of glucose uptake.This indicates that new protein synthesis is required for increased GLUT-4 translocation.In conclusion,these findings suggest that MFMC is enhancing the glucose uptake significantly and dose dependently through the enhanced expression of PPAR and GLUT-4 in vitro.