Effect of different resistance-training regimens on the WNT-signaling pathway
- 504 Downloads
The purpose of the present study was to evaluate the effects of 8 weeks of strength and power training on the expression of genes related to the canonical WNT pathway and β-catenin protein levels in physically active men. Twenty-five subjects (27.4 ± 4.6 years) were balanced based on their relative maximum strength in the squat exercise (squat 1RM/body mass) and randomly assigned to strength training (ST) (n = 10), power training (PT) (n = 10), and control (C) (n = 5) groups. The ST and the PT groups performed high and low intensity squats, respectively, thrice a week, for 8 weeks. Muscle biopsies from the vastus lateralis muscle were collected before and after the training period. Relative strength and power increased similarly in both ST and PT groups (P < 0.001). Fiber cross-sectional area also increased similarly in both ST and PT groups. Gene expression and β-catenin protein expression levels were assessed by real-time PCR and Western blot. Certain genes were up-regulated in the ST group (WNT1: 6.4-fold, P < 0.0001; SFRP1: 3.3-fold, P < 0.0001 and LEF1: 7.3-fold, P < 0.0001) and also in the PT group (WNT1: 24.9-fold, P < 0.0001; SFRP1: 2.7-fold, P < 0.0001; LEF1: 34.1-fold, P < 0.0001 and Cyclin D1: 7.7-fold, P < 0.001). In addition, the expression of key WNT pathway genes was substantially more responsive to PT than to ST (WNT1: P < 0.0001; LEF1: P < 0.0001 and Cyclin D1: P < 0.001). Finally, the total β-catenin protein content increased only in the PT group (P < 0.05). Our data indicate that a PT regimen triggers greater responses in key elements of the WNT pathway.
KeywordsSkeletal muscle Gene expression Strength Power
The authors express their gratitude to Antonio Garcia Soares for excellent technical assistance. This work was supported by FAPESP (Fundação de Amparo a Pesquisa do Estado de São Paulo, Brazil), Grants: 08/58415-3, 07/52288-7, 06/00302-3 and 06/61523-7.
- Angelis E, Garcia A, Chan SS, Schenke-Layland K, Ren S, Goodfellow SJ, Jordan MC, Roos KP, White RJ, MacLellan WR (2008) A cyclin D2–Rb pathway regulates cardiac myocyte size and RNA polymerase iii after biomechanical stress in adult myocardium. Circ Res 102(10):1222–1229PubMedCrossRefGoogle Scholar
- Brown LE, Weir JP (2001) ASEP procedures recommendation I: accurate assessment of muscular strength and power. JEPonline 4(3):1–21Google Scholar
- Burd NA, West DW, Staples AW, Atherton PJ, Baker JM, Moore DR, Holwerda AM, Parise G, Rennie MJ, Baker SK, Phillips SM (2010) Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. PLoS One 5(8):e12033PubMedCrossRefGoogle Scholar
- Campos GE, Luecke TJ, Wendeln HK, Toma K, Hagerman FC, Murray TF, Ragg KE, Ratamess NA, Kraemer WJ, Staron RS (2002) Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. Eur J Appl Physiol 88(1–2):50–60PubMedCrossRefGoogle Scholar
- Welle S, Bhatt K, Pinkert CA, Tawil R, Thornton CA (2007) Muscle growth after postdevelopmental myostatin gene knockout. Am J Physiol 292(4):E985–E991Google Scholar