The effects of different intensity of aerobic exercise on endoplasmic reticulum stress and IL-23 levels

Aim: Today, while the negative effects of sedentary lifestyle on the human body are mentioned, the importance of exercise is emphasized by experts. However, the frequency, intensity, duration and type of exercise should be emphasized. Moderate aerobic exercise is known to have positive effects on the body. There are studies showing that secretion of proinflammatory cytokines and endoplasmic reticulum (ER) stress markers that may cause muscle tissue damage may increase as the intensity of exercise increases. The aim of this study is to investigate whether IL-17 and IL-23 levels in serum change with the effect of different intensity swimming exercise on ER stress. Material and method: The rats were divided into three groups as control (n = 9), normal swimming exercise (NSE) (n = 8), and weight-loaded swimming exercise (WLSE) (n = 9). For 10 weeks, rats in NSE groups were started swimming exercise with 10 minutes and then swimming time was increased for 10 minutes in every 2 weeks time. In the first week of the exercise, rats in the WLSE group were started to swim by tying up a weight of 5% of the body weight of the animal. As in the NSE group, swimming time was increased 10-minutes in every 2 weeks, as well as the bound weight ratio was increased by 1% in every 2 weeks. After sacrificing the animals, the striated muscle and heart tissues were homogenized and the glucose-regulated protein 78 kDA (GRP78 / BIP) and Activating Transcription Factor 4 (ATF4) concentrations in the striated muscle tissue, ATF4 concentrations in the heart muscle were measured by Western Blot technique. IL-23 and IL-17 levels were measured by ELISA from serum samples. Data were compared with Kruskal Wallis test. Significant data were compared by using the relative Benforroni test. Results: There was no significant difference in IL-23 and IL-17 levels between the groups (P> 0.05). GRP78 levels obtained from striated muscle tissue decreased significantly in NSE group compared to WLSE and control group. ATF4 protein levels were significantly increased compared to WLSE I group and control group. ATF4 levels in heart muscle were found to be decreased in the WLSE group compared to the NSE group, but there was no significant difference compared to the control group. Conclusion: It was observed that the levels of IL-23 and IL-17, proinflammatory cytokines, did not change in both swimming exercise types, but ER stress markers changed. There was no adequate adaptation response to ER stress in high intensity swimming exercise performed for a long time in heart and striated muscle tissue. Key Words: ER Stress, Swimming Exercise, GRP78, ATF4, IL-23, IL-17