Abstract
Background and Objective: Metabolic syndrome is a common metabolic disorder that occurs as a result of the increasing prevalence of obesity. Studies show that meteorin-like hormone (METRNL), as a protein molecule and one of the new myokines, increases the rate of metabolism and heat production by beige adipose tissue. This hormone also increases fat metabolism in the body by inducing the production of anti-inflammatory cytokines such as IL-4 and also plays a role in reducing the production of inflammatory cytokines. The aim of the present study was to investigate the effect of 12 weeks of aerobic training on serum concentrations of meteoroid-like hormone, IL-4 and metabolic indices in men with metabolic syndrome.
Methods: The method of this study was semi-experimental with a pre-test and post-test design and its statistical population included middle-aged men with metabolic syndrome with an age range of 40-60 years. Accordingly, 20 men with metabolic syndrome were selected as the research sample as available subjects and were randomly divided into two control groups (10 people) and aerobic exercise (10 people). The inclusion criteria for the study included having at least three metabolic risk factors and not having cardiovascular, respiratory and joint diseases and mobility limitations, and not smoking or drinking alcohol. The aerobic exercise protocol was implemented for twelve weeks (three sessions per week, for 60 minutes per session). Blood samples were collected in pre- and post-test conditions to measure serum levels of IL-4, meteoric-like hormone and other variables. Statistical analysis of data was performed using paired t-tests, independent t-tests and Pearson correlation coefficient using SPSS version 22 software at a significance level of p<0.05.
Results: The results showed that in the exercise group, compared to the control group, serum levels of meteoric-like hormone (p=0.001), HDL (p=0.001) and maximum oxygen consumption significantly increased, and LDL (p=0.006), TG (p=0.015), TC (p=0.033)), insulin resistance index (p=0.001) and body composition indices BMI (p=0.033), PBF (p=0.001) and waist circumference (p=0.001) significantly decreased due to the exercise intervention. However, changes in IL-4 (p=0.32), blood sugar (p=0.25) and body weight (p=0.89) were not significant between the two groups. Also, no significant relationship was found between serum levels of meteoric-like hormone and IL-4 with insulin resistance, waist circumference and body fat percentage in the post-test (P <0.05).
Conclusion: Aerobic exercise can be suggested as a suitable non-pharmacological method for activating the white to brown fat conversion pathway and improving metabolic risk indices for men with metabolic syndrome due to its increased levels of METRNL and favorable effects on metabolic risk factors.