Effects of Low-Intensity Treadmill Exercise on Sciatic Nerve in Experimental Diabetic Neuropathy.

OBJECTIVE

To investigate the potential beneficial effects of low-intensity exercise on histopathological changes of sciatic nerves in streptozotocin (STZ)-induced diabetic rats.

STUDY

DESIGN

The rats were allotted randomly into 3 experimental groups: A (control), B (diabetic untreated), and C (diabetic treated with low-intensity exercise); each group contained 8 animals. Groups B and C received STZ. Diabetes was induced in 2 groups by a single intraperitoneal injection of STZ (40 mg/kg, freshly dissolved in 0.1 M citrate buffer, pH 4.2). Two days after STZ treatment, diabetes in 2 experimental groups was confirmed by measuring blood glucose levels. Rats with blood glucose levels ≥ 250 mg/dL were considered to be diabetic. Animals in the exercise group were made to run the treadmill once a day for 4 consecutive weeks. Exercise started 3 days prior to STZ administration.

RESULTS

The treatment of low-intensity exercise caused a sharp decrease in the elevated serum glucose and an increase in the lowered serum insulin concentrations in STZ-induced diabetic rats. STZ induced a significant decrease in the area of insulin-immunoreactive β cells. Low-intensity exercise treatment resulted in increased area of insulin-immunoreactive β cells signficantly. Myelin breakdown decreased significantly after treatment with low intensity exercise. The ultrastructural features of degenerated axons also showed remarkable improvement.

CONCLUSION

We believe that further preclinical research into low-intensity exercise may indicate its usefulness as a potential treatment for peripheral neuropathy in STZ-induced diabetic rats.