Effects of different intensities of endurance training on serum fibroblast growth factor level, glucose, and insulinresistance in streptozotocin-diabetic male rats

Background and aims: Fibroblast growth factor ۲۱ (FGF۲۱) is a myokine which is produced and secreted by skeletal muscle. Given theinconsistent results on the relationship between the intensity of training and the improvement of blood indices in diabetic patients, thecurrent research investigated the effect of endurance training at different intensities on serum FGF۲۱ level, glucose, and insulin resistancein streptozotocin (STZ)-diabetic male rats.Methods: To this end, ۵۰ rats (with a mean weight of ۲۳.۲۸±۲۵.۰۵ g) were randomly divided into healthy (non-diabetic) control, diabeticcontrol, as well as low, moderate, and high-intensity endurance training groups. Diabetes was induced in all rats by the injection of STZ.Three days after STZ injection, the blood samples were taken from the cut tip of the tails, and those rats with blood glucose levels above۳۰۰ mg/dL were considered diabetic and included in the study. The program included ۸-week aerobic training at different intensities. Theblood samples (۵ cc) were directly collected from the hearts ۴۸ hours after the last training session, followed by measuring the serumFGF۲۱ level, glucose, and insulin. Finally, the analysis of variance and Bonferroni post-hoc test were used for inter-group comparison andthe significance level was considered <۰.۰۵.Results: Based on the results, the serum glucose level, insulin resistance, and FGF۲۱ reduced after eight weeks of endurance training. Thereduction of FGF۲۱ in higher intensity endurance training group was greater compared to the other groups (P < ۰.۰۵) and the reduction ofglucose in moderate intensity group was more significant in comparison to that of the other groups (P < ۰.۰۰۱). However, the insulin levelincreased, which was more pronounced in the moderate intensity training group compared to the other groups (P = ۰.۰۰۲).Conclusion: Overall, both moderate and high-intensity endurance training led to a comparatively more effective reduction in bloodglucose and insulin resistance. Therefore, these two parameters may have a protective effect on the complications associated with diabetesin the rats.

کلیدواژه ها:

Endurance training ، Fibroblast growth factor ، Insulin resistance ، Diabetes