Effect of Regular Aerobic Training and Garlic Extract Consumption on Plasma NO Levels and Tissue VEGF of the Soleus and Gastrocnemius Muscles in Elderly Rats

Objective: Elderly age is accompanied with reduced muscle strength and mass. Vascular endothelial growth factor (VEGF) is the most important stimulant of angiogenesis in muscles which, by increasing blood flow to the muscles, causes muscle strength and endurance. Exercise training leads to increased nitric oxide (NO) and release of VEGF by raising the shear stress during proliferation of endothelial cells and the process of angiogenesis. Garlic also modulates blood flow. This study has assessed the effects of regular swimming training combined with the consumption of garlic extract on the levels of NO plasma and VEGF tissue of soleus slow-twitch and gastrocnemius fast-twitch muscles in aged rats. Methods: Male aged rats (۴۰-۵۰ weeks) with an average weight of ۲۵۰-۳۰۰ g were randomly divided into ۵ groups (n=۷ rats per group) - control, saline, aerobic training, garlic, and aerobic training + garlic. The swimming training program was scheduled for ۵۰ m daily, ۳ times per week for ۸ weeks. The groups that received supplements and supplementary training were given a daily dose by gavage of ۱ ml/kg body weight of the garlic extract for ۸ weeks. We collected tissue and blood samples ۴۸ h after the last training session and after a ۱۰-۱۲ h fasting period. The amount of NO and VEGF were detected by colorimetry and ELISA, respectively. Results: One-way ANOVA revealed that regular aerobic training increased plasma NO (P=۰.۰۰۱), VEGF of the soleus muscle tissue (P<۰.۰۰۱), and VEGF of the gastrocnemius muscle (P=۰.۰۰۴) in the aged rats. In the group that received garlic extract, there was a significant increase in NO levels (P=۰.۰۰۱), and VEGF in the soleus muscle tissue (P=۰.۰۰۷) and gastrocnemius muscle tissue (P=۰.۰۱۵). Combined training and garlic supplement significantly increased the plasma level of NO (P<۰.۰۰۱), and VEGF in the soleus muscle tissue (P<۰.۰۰۱) and gastrocnemius muscle tissue (P=۰.۰۰۱) compared to the control and saline groups. Conclusion: Consumption of garlic extract alone and combined with aerobic training significantly increased plasma NO levels, and VEGF of the soleus and gastrocnemius muscle tissues. However, while the extents of increase in the training combined with garlic extract group was higher than that of the garlic group, there was no significant difference observed between the two groups. The lack of significant difference between these two groups might be due to the intensity and type of the training and would need additional research.

کلیدواژه ها:

Aerobic training ، Garlic ، Soleus and Gastrocnemius muscles ، VEGF ، NO ، تمرین هوازی ، سیر ، عضلات نعلی و دوقلو ، عامل رشد اندوتلیال عروقی ، نیتریک اکساید