RESUMEN
ABSTRACT: Guilherme, JPLF, Semenova, EA, Borisov, OV, Kostryukova, ES, Vepkhvadze, TF, Lysenko, EA, Andryushchenko, ON, Andryushchenko, LB, Lednev, EM, Larin, AK, Bondareva, EA, Generozov, EV, and Ahmetov, II. The BDNF-increasing allele is associated with increased proportion of fast-twitch muscle fibers, handgrip strength, and power athlete status. J Strength Cond Res 36(7): 1884-1889, 2022-The brain-derived neurotrophic factor (BDNF) is involved in neurogenesis and formation of regenerated myofibers following injury or damage. A recent study suggested that the BDNF overexpression increases the proportion of fast-twitch muscle fibers, while the BDNF deletion promotes a fast-to-slow transition. The purpose of this study was to evaluate the association between the BDNF gene rs10501089 polymorphism (associated with blood BDNF levels), muscle fiber composition, and power athlete status. Muscle fiber composition was determined in 164 physically active individuals (113 men, 51 women). BDNF genotype and allele frequencies were compared between 508 Russian power athletes, 178 endurance athletes, and 190 controls. We found that carriers of the minor A-allele (the BDNF-increasing allele) had significantly higher percentage of fast-twitch muscle fibers than individuals homozygous for the G-allele (males: 64.3 [7.8] vs. 50.3 [15.8]%, p = 0.0015; all subjects: 64.1 ± 7.9 vs. 49.6 ± 14.7%, p = 0.0002). Furthermore, the A-allele was associated (p = 0.036) with greater handgrip strength in a sub-group of physically active subjects (n = 83) and over-represented in power athletes compared with controls (7.7 vs. 2.4%, p = 0.0001). The presence of the A-allele (i.e., AA+AG genotypes) rather than GG genotype increased the odds ratio of being a power athlete compared with controls (odds ratio [OR]: 3.43, p = 0.00071) or endurance athletes (OR: 2.36, p = 0.0081). In conclusion, the rs10501089 A-allele is associated with increased proportion of fast-twitch muscle fibers and greater handgrip strength, and these may explain, in part, the association between the AA/AG genotypes and power athlete status.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Fuerza de la Mano , Fibras Musculares de Contracción Rápida , Alelos , Atletas , Factor Neurotrófico Derivado del Encéfalo/genética , Femenino , Fuerza de la Mano/fisiología , Humanos , Masculino , Fuerza Muscular/fisiologíaRESUMEN
Guilherme, JPLF, Egorova, ES, Semenova, EA, Kostryukova, ES, Kulemin, NA, Borisov, OV, Khabibova, SA, Larin, AK, Ospanova, EA, Pavlenko, AV, Lyubaeva, EV, Popov, DV, Lysenko, EA, Vepkhvadze, TF, Lednev, EM, Govorun, VM, Generozov, EV, Ahmetov, II, and Lancha Junior, AH. The A-allele of the FTO gene rs9939609 polymorphism is associated with decreased proportion of slow oxidative muscle fibers and over-represented in heavier athletes. J Strength Cond Res 33(3): 691-700, 2019-The purpose of this study was to explore the frequency of the FTO T > A (rs9939609) polymorphism in elite athletes from 2 cohorts (Brazil and Russia), as well as to find a relationship between FTO genotypes and muscle fiber composition. A total of 677 athletes and 652 nonathletes were evaluated in the Brazilian cohort, whereas a total of 920 athletes and 754 nonathletes were evaluated in the Russian cohort. It was found a trend for a lower frequency of A/A genotype in long-distance athletes compared with nonathletes (odds ratio [OR]: 0.65; p = 0.054). By contrast, it was found an increased frequency of the A-allele in Russian power athletes. The presence of the T/A + A/A genotypes rather than T/T increased the OR of being a Russian power athlete compared with matched nonathletes (OR: 1.45; p = 0.002). Different from that observed in combat sports athletes of lighter weight categories, the A-allele was also over-represented in combat sports athletes of heavier weight categories. The presence of the T/A + A/A genotypes rather than T/T increased the OR of being a combat sports athlete of heavier weight categories compared with nonathletes (OR: 1.79; p = 0.018). Regarding the muscle fibers, we found that carriers of the A/A genotype had less slow-twitch muscle fibers than T-allele carriers (p = 0.029). In conclusion, the A/A genotype of the FTO T > A polymorphism is under-represented in athletes more reliant on a lean phenotype and associated with decreased proportion of slow-twitch muscle fibers, while is over-represented in strength and heavier athletes.