Effects of physical training on the liver igf-i in experimental diabetic rats

Abstract

To investigate the influence of aerobic physical training on IGF-I concentrations in diabetic rats, male wistar rats were allocated into four groups: sedentary control, trained control, sedentary diabetic and trained diabetic. Diabetes was induced by Alloxan (32 mg/kg b.w.) and training protocol consisted of swimming 1hour/day, 5 days/week, during 8 weeks, supporting 5% b.w. During the experimental period, rats weight, water and food ingestion were weekly colected. In the 7th week, blood was collected for glicose and insulin in fasting to Homa index determination. At the end of this period, rats were sacrificed and blood was collected for determinations of serum glucose, insulin, albumin, triglycerides, IGF-I and hematocrit. Gastrocnemius and soleus muscle samples were collected for glycogen determination. Samples of myocardium were used to determine glycogen and triglyceride contents and of liver to determine glycogen, triglyceride, protein, DNA and IGF-I concentrations. Diabetes increased fasting and fed state glycemia, triglyceridemia, cardiac glycogen and triglyceride younder hepatic DNA. The disease still reduced fasting and fed state insulinemia, hepatic ratio protein/DNA and IGF-I concentrations in blood and liver. Physical training protocol was able to reduce fasting and fed state serum glucose, triglyceridemia, cardiac glycogen and trygliceride and hepatic DNA, to increase gastrocnemius muscle glycogen and to recover hepatic ratio protein/DNA and blood and hepatic IGF-I concentrations in diabetic animals. In conclusion, moderate physical training improved the metabolic and endocrine conditions, particulary in GH-IGF axis, in diabetic rats.