Effects of DEHP and its metabolite MEHP on insulin signalling and proteins involved in GLUT4 translocation in cultured L6 myotubes

Graphical abstract Legend for concept diagram. A proposed schematic diagram to show the effect of DEHP and MEHP on insulin signalling molecules and GLUT4 translocation in L6 myotubes. Downregulated proteins are represented as in different color for DEHP (red) and MEHP (blue). Upregulated proteins are indicated as . GLUT4 translocation during insulin – stimulated condition is represented in the figure. – GLUT4 Storage Vesicle, – GLUT4, – VAMP2, – IRAP, – Syntaxin 4. Re-orientation of Munc 18c during insulin-stimulated condition is represented in the figure. Insulin signalling molecules (IR, pIRTyr1162/1163 , IRS1, pIRS1Tyr632 , pAktTyr315 , pAktSer473 , pAktThr308 , AS160, pAS160Thr642 , Rab8A, Rab13, GSK3β and pGSK3βSer9 as well as GLUT4 (cytosol and plasma membrane) proteins were found to be decreased. Proteins involved in GLUT4 translocation such as Syntaxin-4, Synip, SNAP-23 (plasma membrane) were found to be decreased upon DEHP and MEHP treatment whereas Munc18c and SNAP23 (cytosol) proteins were significantly increased upon DEHP treatment and decreased upon MEHP treatment.