Low-intensity running exercise enhances the capillary volume and pro-angiogenic factors in the soleus muscle of type 2 diabetic rats.

INTRODUCTION

We determined the effects of low-intensity exercise on the three-dimensional capillary structure and associated angiogenic factors in the soleus muscle of Goto-Kakizaki (GK) diabetic rats.

METHODS

Four groups of male rats were studied: sedentary nondiabetic (Con), exercised nondiabetic control (Ex), sedentary GK, and exercised GK (GK+Ex). Rats in the Ex and GK+Ex groups were subjected to chronic low-intensity running on a treadmill (15 m/min, 60 min/session, 5 sessions/week for 3 weeks).

RESULTS

Although mean capillary volume and diameter were lower in the GK compared with all other groups, low-intensity exercise increased both of these measures in GK rats. Mitochondrial markers, i.e., SDH activity and PGC-1α expression, and the levels of angiogenic factors were higher in the GK+Ex than all other groups. Exercise increased vascular endothelial growth factor (VEGF) protein levels and the VEGF-to-TSP-1 ratio, an indicator of angiogenesis, in GK rats.

CONCLUSIONS

Combined, the results indicate that low-intensity exercise reduces some of the microcirculatory complications in type 2 diabetic muscles.