Differential effects of rosiglitazone on skeletal muscle and liver insulin resistance in A-ZIP/F-1 fatless mice

Diabetes. 2003 Jun;52(6):1311-8. doi: 10.2337/diabetes.52.6.1311.

Abstract

To determine the role of adipocytes and the tissue-specific nature in the insulin sensitizing action of rosiglitazone, we examined the effects of 3 weeks of rosiglitazone treatment on insulin signaling and action during hyperinsulinemic-euglycemic clamps in awake A-ZIP/F-1 (fatless), fat-transplanted fatless, and wild-type littermate mice. We found that 53 and 66% decreases in insulin-stimulated glucose uptake and insulin receptor substrate (IRS)-1-associated phosphatidylinositol (PI) 3-kinase activity in skeletal muscle of fatless mice were normalized after rosiglitazone treatment. These effects of rosiglitazone treatment were associated with 50% decreases in triglyceride and fatty acyl-CoA contents in the skeletal muscle of rosiglitazone-treated fatless mice. In contrast, rosiglitazone treatment exacerbated hepatic insulin resistance in the fatless mice and did not affect already reduced IRS-2-associated PI 3-kinase activity in liver. The worsening of insulin action in liver was associated with 30% increases in triglyceride and fatty acyl-CoA contents in the liver of rosiglitazone-treated fatless mice. In conclusion, these data support the hypothesis that rosiglitazone treatment enhanced insulin action in skeletal muscle mostly by its ability to repartition fat away from skeletal muscle.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adipocytes / drug effects
  • Adipocytes / metabolism
  • Adipose Tissue / drug effects
  • Adipose Tissue / metabolism
  • Adipose Tissue / transplantation
  • Animals
  • Blood Glucose / drug effects
  • Body Weight / drug effects
  • Female
  • Glucose Clamp Technique
  • Hypoglycemic Agents / pharmacology
  • Insulin / blood
  • Insulin Resistance / physiology*
  • Liver / drug effects
  • Liver / metabolism*
  • Male
  • Mice
  • Mice, Mutant Strains
  • Muscle, Skeletal / drug effects
  • Muscle, Skeletal / metabolism*
  • Rosiglitazone
  • Thiazoles / pharmacology*
  • Thiazolidinediones*

Substances

  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin
  • Thiazoles
  • Thiazolidinediones
  • Rosiglitazone