THE COMPARATIVE METHYLOME ANALYSIS AFTER ACUTE ENDURANCE EXERCISE

Abstract

One of the processes of epigenetic modifications is DNA methylation. It is an epigenetic mechanism in which a methyl group is added to a cytosine's C5 position to produce 5-methylcytosine [1]. The most prevalent sites for DNA methylation are CpG sites, or cytosine-guanine (C-G) base pairs. CpG islands are CpG-rich regions found in gene regulatory regions such as the promoter and enhancer. The bulk of CpG sites in humans (70-80%) are methylated [2, 3]. When methylation is present or increases (hypermethylation), transcription factors are unable to bind to specific areas of the gene, and gene expression is reduced [4]. Conversely, loss of methyl groups (hypomethylation) at specific sites might enable/increase gene expression. Cancer risk [5, diabetes [6, CVDs [7], major depressive disorder [8, autoimmune disorders [9], and aging [10] have all been related to changes in DNA methylation at specific genomic locations. Exercise has been shown to affect DNA methylation profiles in blood, muscle, and adipose tissue in earlier investigations [11, 12, 13, 14]. The effects of various forms of exercise on DNA methylation were investigated. In humans, aerobic exercise training alters the methylome of skeletal muscle, hypomethylating the genome more frequently in patients with type 2 diabetes and obesity [15, 16]. Eight young (21.1 2.2 years) males undertook 8 weeks of supervised, thrice-weekly resistance exercise training consisting of three sets of 8–12 repetitions with a weight comparable to 80% of 1RM, as well as changes in genome-wide DNA methylation and gene expression [13]. Furthermore, the duration of activities varies amongst research. Some research looked at chronic exercise regimes, while others looked at acute exercise protocols. In one research, two different sport-relevant high-intensity running protocols were used: Exercises: 2) straight line vs. 1) change of direction (COD) (ST). Researchers took skeletal muscle samples 44 from the vastus lateralis 30 minutes and 24 hours after exercise. Exercise alone caused substantial alterations in the 50 methylome 30 minutes and 24 hours after exercise in both conditions, particularly in the MAPK, AMPK, and axon guidance 51 pathways [12]. Only a few studies, however, have looked at DNA methylation across the genome in healthy human blood after acute endurance exercise.