The Effects of Exercise on Telomere Length in Persons with Heart Failure

Introduction Heart failure (HF) is a disease of premature cellular aging, and telomere length, a measure of cellular age, is reduced in persons with HF. Chronic inflammation in HF is associated with worse outcomes. While inflammation is a putative mechanism contributing to telomere shortening, this relationship has yet to be explored in HF. Although physical activity has been known to increase telomere length, the effects in HF are unknown. Therefore, the purpose of this study is to examine the effects of exercise on telomere length and the relationship with interleukin [IL]-1β in persons with HF. Methods This study is a secondary analysis of stored samples from persons with HF who participated in a 3-month home-based aerobic exercise intervention (n=15) or received usual care (n=15). IL-1β was measured in triplicate via ELISA. DNA was extracted from peripheral blood mononuclear cells. Absolute telomere length was measured in triplicate via quantitative real-time PCR. The Student's t-test was used to examine between group and within group differences at baseline and 3-months, and Pearson correlations were used to examine relationships between telomere length and cytokines. Effect size was calculated using Hedges’ g. All data were analyzed using SAS version 9.4 with an alpha set at 0.05. Results Plasma IL-1β was lower among the exercise group compared to control at 3 months (1.08 ± 0.07 pg/mL vs. 1.80 ± 0.2 pg/mL; p Conclusions In this short-term study, a home-based walking intervention displays encouraging results related to the increase in telomere length and reduction of IL-1β in HF. The association between telomere length and IL-1β suggest a relationship between inflammation and cellular aging. Implications Moderate intensity exercise can help to maintain cellular function, thus improving outcomes in persons with HF.