The Effect of Eight Weeks Aerobic Training Alone or Combined with Grape Seed Extract Supplementation on the Myocardial Expression of VEGF and VEGFR-2 in the Streptozotocin-induced Diabetic Rats

The angiogenesis process is disrupted in the heart tissue during diabetes. In contrast, exercise training is one of the effective factors on the angiogenesis process. The present study was conducted aiming at investigating the effect of eight weeks aerobic training alone or combined with grape seed extract supplementation on the myocardial expression of VEGF and VEGFR-2 in the streptozotocin-induced (STZ) diabetic rats. Thirty-two diabetic male Wistar rats with initial weight of 160-220 g were randomly assigned to four groups including control, supplement, training, and training + supplement groups, each consisting of eight rats. Type1 diabetes induced by STZ injection (55 mg/kg/bw). Aerobic training conducted for eight weeks and five sessions per week. Grape seed extract supplement was administrated by oral gavage at a dose of 40 mg/kg daily. Two day after the last training session or grape seed extract supplementation, all rats were anesthetized by means of ketamine–xylazine injection and their heart tissues were removed. VEGF and VEGFR-2 gene expression in the heart tissue were determined by Real-time PCR method and data were analyzed by SPSS software and one-way ANOVA test. The present study’s findings indicated that myocardial VEGF expression in training, supplement, and training + supplement groups were significantly higher compared to the control group (p<0.05). In addition, VEGFR-2 expression in training and training + supplement groups indicated a significant increase compared to control and supplement groups (p<0.05). The current study’s finding indicated that aerobic training alone and in combination with grape seed extract supplementation played a key role in increasing the expression of myocardial angiogenic factors in type 1 diabetic rats. However, consumption of grape seed extract along with aerobic training cannot have a synergistic effect on VEGF and VEGFR-2 expression.