Long-term exercise training decreases interleukin-6 (IL-6) serum levels in subjects with impaired glucose tolerance: effect of the −174G/C variant in IL-6 gene

Abstract

Objective: Exercise training has been shown to have anti-inflammatory effects in patients with type 2 diabetes. Changes in interleukin-6 (IL-6) serum concentrations in response to training could contribute to these beneficial effects. However, there are heterogeneous data on whether circulating IL-6 is altered by exercise training. We therefore hypothesize that genetic factors modify the individual changes in IL-6 levels after long-term training. Research design and methods:The K174G/C variant in the IL-6 gene was genotyped in 60 subjects with impaired glucose tolerance. For a 12-month interventional study, patients were randomized into three groups: a control group (nZ16) was compared with one group, which underwent a standardized training program (nZ24) and another group, which was treated with 4 mg rosiglitazone once daily (nZ20). At baseline, after 1, 6, and 12 months, we measured anthropometric parameters and serum concentration of IL-6 and, at baseline and after 12 months, we determined glucose tolerance and fitness level. Results: Only in subjects carrying the SNP K174C allele did long-term exercise training result in significantly reduced IL-6 serum concentrations. Multivariate linear regression analysis identified the IL-6 genotype as a significant predictor of changes in IL-6 serum concentrations independent of age, gender and improvement in body mass index, hemoglobin (Hb)A 1c , and fitness level in response to training. Conclusions: Genetic variants in the IL-6 gene significantly modify changes in IL-6 serum concentrations in response to long-term exercise training programs. Our data suggest that genetic factors are important determinants for the individual response to anti-inflammatory effects of exercise training. 159 129-136 European Journal of Endocrinology

The Effects of 12 Weeks Regular Aerobic Exercise on Brain-derived Neurotrophic Factor and Inflammatory Factors in Juvenile Obesity and Type 2 Diabetes Mellitus

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“…They found that the aerobic exercise group showed significant reductions in CRP, L-6, and IL-18. Additionally, a study of middle-aged men and women performing endurance exercise, consisting of one 60-minute training session per week for 12 months, reported a significant decrease in serum CRP levels following a reduction in BMI14 ) .…”

Effects of lifelong exercise training on mammary tumorigenesis induced by MNU in female Sprague–Dawley rats

“…In order to give new insights on the impact of lifelong exercise training on mammary tumorigenesis, we used a recognized animal model of breast cancer that was submitted to treadmill exercise during 35 weeks. The N-methyl-N-nitrosourea (MNU)-induced mammary cancer in mice and rats is the most used model to study mammary carcinogenesis [22,23]. To our knowledge, this is the first study to evaluate the effects of the long-term exercise training on rat mammary tumorigenesis.…”

Adiponectin (+276 G/T), Tumor Necrosis Factor-alpha (-308 G/A) and Interleukin-6 (-174 C/G) Genes Polymorphisms in Egyptian Type 2 Diabetic Patients

“…Analyses of small cohorts of native Americans and Spanish Caucasians [51], Brazilian [52], Polish [53] and German [54] populations, showed the 'G' allele of -174 C/G SNP to be associated with higher risk of T2DM ,but this SNP was not linked with diabetes in the Finnish Diabetes Prevention Study [46] and Australian population [55].…”