Epigenetic effects of physical activity in elderly patients with cardiovascular disease

Cardiovascular disease (CVD) is an important public health problem affecting especially the elderly. Over the past 20years, an increasing number of studies have examined its underlying pathophysiological mechanisms and new therapies are continually being discovered. However, despite considerable progress in CVD management, mortality and morbidity remain a major healthcare concern, and frequent hospital admissions compromise the daily life and social activities of these patients. Physical activity has emerged as an important non-pharmacological adjunctive therapy for CVD in older patients, especially for heart failure patients, exerting its beneficial effects on mortality, morbidity, and functional capacity. The mechanisms underlying the cardiovascular benefits of exercise are not wholly clear. Mounting evidence suggest that epigenetic modifications, such as DNA methylation, histone post-translational modifications (hPTMs) and non-coding RNA, especially microRNAs (miRNAs), may be induced by physical activity. Recently, a number of miRNAs have been identified as key players in gene expression modulation by exercise. MiRNAs are synthesized by living cells and actively released into the bloodstream through different shuttles. The epigenetic information, thus carried and delivered, is involved in the interplay between environmental factors, including physical activity, and individual genetic make-up. We review and discuss the effects of exercise on age-related CVDs, focusing on circulating miRNA (c-miRNAs) modulation. Epigenetic mechanisms may have clinical relevance in CVD prevention and management; since they can be modified, insights into the implications of lifestyle-related epigenetic changes in CVD etiology may help develop therapeutic protocols of exercise training that can be suitable and effective for elderly patients.