INS and obesity due to melanocortin 4 receptor deficiency: As presented in Fig. 1A, insulin-stimulated glycogen synthesis was reduced in myotubes from women with severe obesity compared with lean donors (10.9 ± 0.5 vs. 9.4 ± 0.2 nmol/min/mg, for lean vs. severely obese, respectively, P < 0.05) with and without resveratrol treatment.