Regular exercise participation improves genomic stability in diabetic patients: an exploratory study to analyse telomere length and DNA damage

Physical activity demonstrated to be effective as prevention and treatment for different chronic conditions, including type 2 diabetes. In particular, several studies highlighted as its beneficial effects may be related to a major stability of the DNA molecule, such as the telomeric ends. Here we analyze the effect of exercise training on telomere length, spontaneous and H 2 O 2 -induced DNA damage, as well as the apoptosis level in leukocytes from untrained or trained type 2 diabetic (T2D) patients or age-matched healthy subjects (HS). Moreover, the expression analysis of selected genes belonging to DNA repairs systems, cell cycle control, as well as to antioxidants and defence systems was performed. Our findings demonstrate that diabetic patients participating to a regular exercise program show a longer telomere sequence and a substantial reduction of spontaneous DNA damage. Further, ex vivo treatment of leukocytes with H 2 O 2 highlighted: 1) a preferential telomere attrition; 2) a decreased susceptibility to DNA damage in leukocytes of trained T2D patients with respect to untrained ones, and 3) a relationship between DNA damage and cell apoptosis. Finally, the gene expression analysis in T2D subjects suggests an adaptive response to prolonged exercise training aimed at improving the response of specific genes.