title: Acute responses of circulating microRNAs to low-volume sprint interval cycling.
abstract: Low-volume high-intensity interval training is an efficient and practical method of inducing physiological responses in various tissues to develop physical fitness and may also change the expression of circulating microRNAs (miRNAs). The purpose of the present study was to examine whether miRNAs for muscle, heart, somatic tissue and metabolism were affected by 30-s intervals of intensive sprint cycling. We also examined the relationship of these miRNAs to conventional biochemical and performance indices. Eighteen healthy young males performed sprint interval cycling. Circulating miRNAs in plasma were detected using TaqMan-based quantitative PCR and normalized to Let-7d/g/i. In addition, we determined the levels of insulin-like growth factor-I, testosterone and cortisol, and anaerobic capacity. Compared to plasma levels before exercise muscle-specific miR-1 (0.12 ± 0.02 vs. 0.09 ± 0.02), miR-133a (0.46 ± 0.10 vs. 0.31 ± 0.06), and miR-133b (0.19 ± 0.02 vs. 0.10 ± 0.01) decreased (all P < 0.05), while miR-206 and miR-499 remained unchanged. The levels of metabolism related miR-122 (0.62 ± 0.07 vs. 0.34 ± 0.03) and somatic tissues related miR-16 (1.74 ± 0.27 vs. 0.94 ± 0.12) also decreased (both P < 0.05). The post-exercise IGF-1 and cortisol concentrations were significantly increased, while testosterone concentrations did not. Plasma levels of miR-133b correlated to peak power (r = 0.712, P = 0.001) and miR-122 correlated to peak power ratio (r = 0.665, P = 0.003). In conclusion sprint exercise provokes genetic changes for RNA related to specific muscle or metabolism related miRNAs suggesting that miR-133b and miR-122 may be potential useful biomarkers for actual physiological strain or anaerobic capacity. Together, our findings on the circulating miRNAs may provide new insight into the physiological responses that are being performed during exercise and delineate mechanisms by which exercise confers distinct phenotypes and improves performance.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University Nanjing, China ; Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University Nanjing, China.
authors.forename: Shu Fang
authors.initials: SF
authors.lastname: Cui
authors.affiliation: The Lab of Military Conditioning and Motor Function Assessment, The PLA University of Science and Technology Nanjing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: The Lab of Military Conditioning and Motor Function Assessment, The PLA University of Science and Technology Nanjing, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Niu
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University Nanjing, China ; Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University Nanjing, China.
authors.forename: Chen Yu
authors.initials: CY
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University Nanjing, China ; Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University Nanjing, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University Nanjing, China ; Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing University Nanjing, China ; The Lab of Military Conditioning and Motor Function Assessment, The PLA University of Science and Technology Nanjing, China.
authors.forename: Ji Zheng
authors.initials: JZ
authors.lastname: Ma
keywords: anaerobic capacity; biomarkers; blood hormones; blood lactate; plasma microRNAs