ABSTRACT
Objective
To investigate the effects of physical training on metabolic and morphological parameters of diabetic rats.
Methods
Wistar rats were randomized into four groups: sedentary control, trained control, sedentary diabetic and trained diabetic. Diabetes mellitus was induced by Alloxan (35mg/kg) administration for sedentary diabetic and Trained Diabetic Groups. The exercise protocol consisted of swimming with a load of 2.5% of body weight for 60 minutes per day (5 days per week) for the trained control and Trained Diabetic Groups, during 6 weeks. At the end of the experiment, the rats were sacrificed and blood was collected for determinations of serum glucose, insulin, albumin and total protein. Liver samples were extracted for measurements of glycogen, protein, DNA and mitochondrial diameter determination.
Results
The sedentary diabetic animals presented decreased body weight, blood insulin, and hepatic glycogen, as well as increased glycemia and mitochondrial diameter. The physical training protocol in diabetic animals was efficient to recovery body weight and liver glycogen, and to decrease the hepatic mitochondrial diameter.
Conclusion
Physical training ameliorated hepatic metabolism and promoted important morphologic adaptations as mitochondrial diameter in liver of the diabetic rats.
Diabetes mellitus; Exercise; Liver; Wistar, rats
(A) Representative micrograph of rat hepatic tissue from the Sedentary Control Group. This micrograph shows the abundance of mitochondria (m) around the nucleus (N) and in the smooth endoplasmic reticulum (rl). Note some abundance of nuclear pores (arrow) (10,250x). (B) Representative micrograph of rat hepatic tissue of the Trained Control Group. This micrograph shows the abundance of peroxisomes (P) among the mitochondriae (m) and the smooth endoplasmic reticulum (rl). The presence of material with lipid aspects (L) is observed, but without the characteristic delimitation of typical droplets (14,500x).
(A) Representative micrograph of rat hepatic tissue of the Sedentary Diabetic Group. The altered appearance of the nucleus (N) and large lipid droplets (L) stand out. In addition, irregularities in the inner membrane (o) of the nuclear envelop, and the presence of smooth endoplasmic reticulum around the nucleus, as well as rough endoplasmic reticulum in smaller amounts (14,500x). (B) Representative micrograph of hepatic tissue of rat Diabetic Trained Group. The vacuolated smooth endoplasmic reticulum (rl) with is located among the mitochondriae (m). Note also the presence of glycogen (g) and myelin figures (f) (21,000x).
Data expressed as mean±standard deviation. a p<0.05 versus Sedentary Control; b p<0.05 versus Trained Control. d p<0.05 versus Trained Diabetic.
(A) Representative micrograph of rat hepatic tissue Sedentary Control Group. A large amount of rough endoplasmic reticulum (rr) is observed, besides peroxosome (P) and mitochondria (m) (41,000x). (B) Representative micrograph of hepatic tissue of rat Sedentary Diabetic Group. Large vacuoles of the smooth reticulum (rl), some ribosomes (r), the presence of myelin figures and mitochondria with high diameter (m) are noted (41,000x).