Nonacute effects of H-FABP deficiency on skeletal muscle glucose uptake in vitro.
Heart-type fatty acid-binding protein (H-FABP) is required for high rates of skeletal muscle long-chain fatty acid (LCFA) oxidation and esterification. Here we assessed whether H-FABP affects soleus muscle glucose uptake when measured in vitro in the absence of LCFA. Wild-type and H-FABP null mice were fed a standard chow or high-fat diet before muscle isolation. With the chow, the mutation increased insulin-dependent deoxyglucose uptake by 141% (P < 0.01) at 0.02 mU/ml of insulin but did not cause a significant effect at 2 mU/ml of insulin; skeletal muscle triglyceride and long-chain acyl-CoA (LCA-CoA) levels remained normal. With the high-fat diet, the mutation increased insulin-dependent deoxyglucose uptake by 190% (P < 0.01) at 2 mU/ml of insulin, thus partially preventing insulin resistance, and it completely prevented the threefold (P < 0.001) diet-induced increase of muscle triglyceride levels; however, muscle LCA-CoA levels showed little or no reduction. With both diets, the mutation reduced the basal (insulin-independent) soleus muscle deoxyglucose uptake by 28% (P < 0.05). These results establish a close relation between FABP-dependent lipid pools and insulin sensitivity and indicate the existence of a nonacute, antagonistic, and H-FABP-dependent fatty acid regulation of basal and insulin-dependent muscle glucose uptake.
Erol
Erdal
E
Dept. of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4467, USA.
Cline
Gary W
GW
Kim
Jason K
JK
Taegtmeyer
Heinrich
H
Binas
Bert
B
D000214:Acyl Coenzyme A / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D004041:Dietary Fats / Q000378:metabolism; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism / Q000493:pharmacokinetics*; D007328:Insulin / Q000502:physiology*; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018482:Muscle, Skeletal / Q000378:metabolism*
D000214:Acyl Coenzyme A; D002352:Carrier Proteins; D004041:Dietary Fats; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D007328:Insulin; D005947:Glucose