AMPK activity and isoform protein expression are similar in muscle of obese subjects with and without type 2 diabetes

K Højlund, KJ Mustard, P Stæhr… - American Journal …, 2004 - journals.physiology.org
K Højlund, KJ Mustard, P Stæhr, DG Hardie, H Beck-Nielsen, EA Richter, JFP Wojtaszewski
American Journal of Physiology-Endocrinology and Metabolism, 2004journals.physiology.org
Acute or chronic activation of AMP-activated protein kinase (AMPK) increases insulin
sensitivity. Conversely, reduced expression and/or function of AMPK might play a role in
insulin resistance in type 2 diabetes. Thus protein expression of the seven subunit isoforms
of AMPK and activities and/or phosphorylation of AMPK and acetyl-CoA carboxylase-β
(ACCβ) was measured in skeletal muscle from obese type 2 diabetic and well-matched
control subjects during euglycemic-hyperinsulinemic clamps. Protein expression of all …
Acute or chronic activation of AMP-activated protein kinase (AMPK) increases insulin sensitivity. Conversely, reduced expression and/or function of AMPK might play a role in insulin resistance in type 2 diabetes. Thus protein expression of the seven subunit isoforms of AMPK and activities and/or phosphorylation of AMPK and acetyl-CoA carboxylase-β (ACCβ) was measured in skeletal muscle from obese type 2 diabetic and well-matched control subjects during euglycemic-hyperinsulinemic clamps. Protein expression of all AMPK subunit isoforms (α1, α2, β1, β2, γ1, γ2, and γ3) in muscle of obese type 2 diabetic subjects was similar to that of control subjects. In addition, α1- and α2-associated activities of AMPK, phosphorylation of α-AMPK subunits at Thr172, and phosphorylation of ACCβ at Ser221 showed no difference between the two groups and were not regulated by physiological concentrations of insulin. These data suggest that impaired insulin action on glycogen synthesis and lipid oxidation in skeletal muscle of obese type 2 diabetic subjects is unlikely to involve changes in AMPK expression and activity.
American Physiological Society