Low ethanol consumption increases insulin sensitivity in Wistar rats.
Several human studies suggest that light-to-moderate alcohol consumption is associated with enhanced insulin sensitivity, but these studies are not free of conflicting results. To determine if ethanol-enhanced insulin sensitivity could be demonstrated in an animal model, male Wistar rats were fed a standard chow diet and received drinking water without (control) or with different ethanol concentrations (0.5, 1.5, 3, 4.5 and 7%, v/v) for 4 weeks ad libitum. Then, an intravenous insulin tolerance test (IVITT) was performed to determine insulin sensitivity. Among the ethanol groups, only the 3% ethanol group showed an increase in insulin sensitivity based on the increase of the plasma glucose disappearance rate in the IVITT (30%, P<0.05). In addition, an intravenous glucose tolerance test (IVGTT) was performed in control and 3% ethanol animals. Insulin sensitivity was confirmed in 3% ethanol rats based on the reduction of insulin secretion in the IVGTT (35%, P<0.05), despite the same glucose profile. Additionally, the 3% ethanol treatment did not impair body weight gain or plasma aspartate aminotransferase and alanine aminotransferase activities. Thus, the present study established that 3% ethanol in the drinking water for 4 weeks in normal rats is a model of increased insulin sensitivity, which can be used for further investigations of the mechanisms involved.
Furuya
D T
DT
Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil.
Binsack
R
R
Machado
U F
UF
D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D002492:Central Nervous System Depressants / Q000008:administration & dosage* / Q000378:metabolism; D004195:Disease Models, Animal; D000431:Ethanol / Q000008:administration & dosage* / Q000378:metabolism; D005951:Glucose Tolerance Test; D007333:Insulin Resistance; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D002492:Central Nervous System Depressants; D000431:Ethanol; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase