Rosiglitazone improves muscle insulin sensitivity, irrespective of increased triglyceride content, in ob/ob mice.
The present study was performed to examine the effects of rosiglitazone treatment on tissue-specific insulin sensitivity. Therefore, we used obese, insulin-resistant ob/ob mice and measured the effects of rosiglitazone treatment on insulin sensitivity and simultaneously tissue-specific uptake of glucose and free fatty acids (FFA) under hyperinsulinemic euglycemic clamp conditions. Rosiglitazone treatment resulted in significantly higher body weight and decreased plasma levels of glucose, insulin, and triglyceride (TG). Glucose tolerance, as well as insulin sensitivity, was improved upon rosiglitazone treatment, as assessed by glucose tolerance and insulin sensitivity tests. Hyperinsulinemic euglycemic clamps showed increased glucose infusion rates with increased whole body insulin sensitivity. Rosiglitazone treatment resulted in increased glucose uptake by cardiac and skeletal muscle under hyperinsulinemic euglycemic clamp conditions, while no differences were observed in FA uptake. Measurement of TG content showed that rosiglitazone treatment resulted in decreased TG content of cardiac muscle, but increased TG content of skeletal muscle. We conclude that rosiglitazone treatment leads to strong improvement of insulin sensitivity, irrespective of increased muscle TG content, in ob/ob mice.
Muurling
Martin
M
TNO-Prevention and Health, Gaubius Laboratory, Leiden, The Netherland.
Mensink
Ronald P
RP
Pijl
Hanno
H
Romijn
Johannes A
JA
Havekes
Louis M
LM
Voshol
Peter J
PJ
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002784:Cholesterol / Q000097:blood; D004032:Diet; D005230:Fatty Acids, Nonesterified / Q000097:blood; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006321:Heart / Q000187:drug effects; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007333:Insulin Resistance / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D000077154:Rosiglitazone; D013844:Thiazoles / Q000494:pharmacology*; D045162:Thiazolidinediones; D014280:Triglycerides / Q000097:blood / Q000378:metabolism*
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007004:Hypoglycemic Agents; D013844:Thiazoles; D045162:Thiazolidinediones; D014280:Triglycerides; D000077154:Rosiglitazone; D002784:Cholesterol