Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth
Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth
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DOI：
10.1152/japplphysiol.00261.2014
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发表时间：
2014-10-15
影响因子：
3.3
通讯作者：
Vissing, Kristian
中科院分区：
文献类型：
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作者：
Farup, Jean;Rahbek, Stine Klejs;Vissing, Kristian
骨骼肌卫星细胞(SCs)参与骨骼肌的重构和肥大过程。然而，对影响骨骼肌中干细胞含量的外在因素知之甚少。在一项比较人类的研究中，我们调查了12周单侧阻力训练中卫星细胞(SCs)的出现、肌肉生长和重塑之间的肌肉纤维类型特异性关联，这些训练是以偏心(ECC)或同心(ConC)阻力训练+/-乳清蛋白(乳清蛋白，19.5g蛋白质+19.5g葡萄糖)或安慰剂(安慰剂，39g葡萄糖)补充进行的。肌肉活检(股外侧肌)分析了纤维类型特异的SCs、肌核和纤维横截面积(CSA)。训练后，I型纤维和II型纤维中的SCs均随着COCC的增加而增加(P<；0.01)，并且与ECC有差异(P<；0.05)，ECC没有增加。各组I型纤维肌核含量均增加(P<；0.01)，而乳清蛋白-CONC组(P<；0.01)和安慰剂-ECC组(P<；0.01)II型纤维肌核特异性增生。类似地，虽然I型纤维CSA在干预后独立增加(P<；0.001)，而II型纤维CSA仅在乳清蛋白-Conc训练后增加(P<；0.01)，而II型纤维肥大与整个肌肉肥大仅在Conc训练后相关(P<；0.01)。总之，单独的向心性伸膝阻力训练似乎比离心性阻力训练对SC含量的驱动作用更强，而当向心性阻力训练与补充乳清蛋白相结合时，II型纤维肥大加剧。
Skeletal muscle satellite cells (SCs) are involved in remodeling and hypertrophy processes of skeletal muscle. However, little knowledge exists on extrinsic factors that influence the content of SCs in skeletal muscle. In a comparative human study, we investigated the muscle fiber type-specific association between emergence of satellite cells (SCs), muscle growth, and remodeling in response to 12 wk unilateral resistance training performed as eccentric (Ecc) or concentric (Conc) resistance training +/- whey protein (Whey, 19.5 g protein + 19.5 g glucose) or placebo (Placebo, 39 g glucose) supplementation. Muscle biopsies (vastus lateralis) were analyzed for fiber type-specific SCs, myonuclei, and fiber cross-sectional area (CSA). Following training, SCs increased with Conc in both type I and type II fibers (P < 0.01) and exhibited a group difference from Ecc (P < 0.05), which did not increase. Myonuclei content in type I fibers increased in all groups (P < 0.01), while a specific accretion of myonuclei in type II fibers was observed in the Whey-Conc (P < 0.01) and Placebo-Ecc (P < 0.01) groups. Similarly, whereas type I fiber CSA increased independently of intervention (P < 0.001), type II fiber CSA increased exclusively with Whey-Conc (P < 0.01) and type II fiber hypertrophy correlated with whole muscle hypertrophy exclusively following Conc training (P < 0.01). In conclusion, isolated concentric knee extensor resistance training appears to constitute a stronger driver of SC content than eccentric resistance training while type II fiber hypertrophy was accentuated when combining concentric resistance training with whey protein supplementation.