Fig. 5: Development of systemic insulin resistance by skeletal muscle-specific overexpression of AMPKα2^S491D.

a Schematic diagram of the experimental protocols. Male Pak4 KO mice fed HFD for 8 weeks were injected intravenously with adeno-associated virus 9 (AAV9) carrying eGFP (eGFP), wild type AMPKα2 (AMPKα2^WT) or phospho-mimetic mutant of AMPKα2 (Ser491 to Asp, AMPKα2^SD) and fed HFD for another 6 weeks. b–e Fasting levels of plasma insulin (b, n = 7), HOMA-IR (c, n = 7), leptin (d, n = 7), and adiponectin (e, n = 7) were compared in these mice. f, g Glucose tolerance (f) and insulin tolerance (g, n = 4 for eGFP and n = 5 for AMPKα2^WT and AMPKα2^SD) and areas of the curve (AOC) were compared in mice. ^*p < 0.05 and ^**p < 0.01 versus AMPKα2^WT. h Insulin-stimulated p-Akt level was analyzed in quadriceps femoris (QF) and gastrocnemius (GAS) muscles by western blotting (n = 3 for Veh and n = 4 for insulin treatment). i AMPK signaling pathways in whole cell lysates of gastrocnemius muscle were assessed by western blotting. Data are presented as the mean ± SD. Unpaired two-tailed t test (b–e) and one-way ANOVA followed by Tukey′s multiple comparisons test (f, g, and h) were conducted for statistical analysis. Source data are provided as a Source Data file.