Effect of food restriction on the insulin signalling pathway in rat skeletal muscle and adipose tissue.
We tried to elucidate the effects of a brief and severe model of food restriction on insulin sensitivity in female rats, focusing on key proteins involved in the insulin signalling pathway in skeletal muscle and adipose tissue after 5, 10 and 15 days of food restriction. Using euglycemic clamp, we detected that food-restricted rats are significantly less sensitive to insulin action than control rats. However, the time of restriction promotes a progressive increase on insulin sensitivity. The analysis of the insulin signalling pathway showed a tissue-specific regulation of several proteins involved in insulin signalling. In skeletal muscle, insulin receptor substrate 1 and Glut4 are up-regulated at the end of the food restriction period, just the opposite of what we found in adipose tissue. In conclusion, a 50% reduction of food intake modulates insulin sensitivity through a tissue-specific regulation of the insulin signalling pathway in the main target tissues for this hormone.
Alonso
Ana
A
Department of Functional Biology, Physiology Area, University of Oviedo, Oviedo, 33006 Spain.
Fernández
Yolanda
Y
Fernández
Rebeca
R
Ordóñez
Patricia
P
Moreno
María
M
Díaz
Fernando
F
Patterson
Angeles M
AM
González
Celestino
C
D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D005260:Female; D005508:Food Deprivation; D015309:Glucose Clamp Technique; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D055504:Insulin Receptor Substrate Proteins; D018482:Muscle, Skeletal / Q000378:metabolism*; D010750:Phosphoproteins / Q000737:chemistry; D010766:Phosphorylation; D011506:Proteins / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D011972:Receptor, Insulin / Q000737:chemistry; D015398:Signal Transduction; D014443:Tyrosine / Q000378:metabolism
D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; C526296:Irs1 protein, rat; D010750:Phosphoproteins; D011506:Proteins; D014443:Tyrosine; D011972:Receptor, Insulin