Muscle contraction stimulates a transient change of myogenic factors, partly related to the mode of contractions. Here, we assessed the response of IGF-1Ea, IGF-1Eb, IGF-1Ec, PGC1α-1, PGC1α-4, and myostatin to the eccentric Vs. the concentric contraction in human skeletal muscle. Ten healthy males were performed an acute eccentric and concentric exercise bout (n = 5 per group). For each contraction type, participants performed 12 sets of 10 repetitions knee extension by the dominant leg. Baseline and post-exercise muscle biopsy were taken 4 weeks before and immediately after experimental sessions from Vastus Lateralis muscle. Genes expression was measured by real-time PCR technique. There was a significant increase in PGC1α-1, PGC1α-4, IGF-1Ea and, IGF-1Eb mRNA after concentric contraction (p ≤ 0.05), while the PGC1α-4 and IGF-1Ec significantly increased after eccentric contraction (p ≤ 0.05). It is intriguing to highlight that; no significant differences between groups were evident for changes in any variables following exercise bouts (p ≥ 0.05). Our results found that concentric and eccentric contractions presented different responses in PGC1α-1, IGF-1Ea, IGF-1Eb, and IGF-1Ec mRNA. However, a similar significant increase in mRNA content was observed in PGC1α-4. Further, no apparent differences could be found between the response of genes to eccentric and concentric contraction.

肌肉收缩会刺激肌源性因子的短暂变化，部分与收缩方式有关。在这里，我们评估的回应IGF - 1EA，IGF - 1EB，IGF - 1EC，PGC1α -1，PGC1α -4和肌肉生长抑制素偏心比。人骨骼肌的同心收缩。十名健康男性接受了一次急性离心和同心运动（n =每组5个）。对于每种收缩类型，参与者通过优势腿进行12组，每组10次重复膝盖伸展。在进行实验的前4周和后4周，分别从Vastus Lateralis肌肉进行基线和运动后肌肉活检。通过实时PCR技术测量基因表达。有在显著增加PGC1α -1，PGC1α -4，IGF - 1EA和，IGF - 1EB mRNA的同心收缩（后p  ≤0.05），而PGC1α -4和IGF - 1EC显著离心收缩后增加（p ≤0.05）。突出这一点很有趣；组之间没有差异显著为以下锻炼较量（改变任何变量是明显的p  ≥0.05）。我们的研究结果发现，同心和离心收缩中呈现出不同的反应PGC1α -1，IGF - 1EA，IGF - 1EB，和IGF - 1EC表达。但是，在PGC1α-4中观察到了类似的mRNA含量显着增加。此外，在基因对离心收缩和同心收缩的反应之间未发现明显差异。