Active muscle regeneration following eccentric contraction-induced injury is similar between healthy young and older adults
Active muscle regeneration following eccentric contraction-induced injury is similar between healthy young and older adults
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DOI：
10.1152/japplphysiol.01350.2012
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发表时间：
2014-06-01
影响因子：
3.3
通讯作者：
Leeuwenburgh, Christiaan
中科院分区：
文献类型：
--
作者：
Buford, Thomas W.;MacNeil, R. Gavin;Leeuwenburgh, Christiaan
骨骼肌损伤后的修复是维持正常肌肉骨骼功能的关键方面。研究表明，再生过程，包括肌生成和血管生成，在老年期间受损，但来自人类的证据有限。这项研究旨在比较健康年轻人和老年人之间的主动肌肉再生。我们评估了急性肌肉损伤后第2天（T2）和第7天（T3）肌肉再生的临床、生化和免疫组化指标的变化。年龄在18-30岁和>= 70岁的男性和女性，性别和体重指数相匹配，以一次重复最大值的110%进行150次足底屈肌单侧离心收缩。采用协方差分析对数据进行分析，并根据性别、习惯性体力活动和结局的基线水平进行调整。共有30名年轻（n = 15; 22.5 +/- 3.7岁）和老年（n = 15; 75.8 +/- 5.0岁）成人完成了研究。肌肉损伤后，T2时，年轻人和老年人的力量产生分别下降了16%和14%，T3时，每组力量恢复到基线力量的93%。尽管反应模式略有差异，但两组间肌源性生长因子肌内浓度和肌钙蛋白（4 '，6-diamidino-2-phenylindole+和配对box 7+）细胞数量的损伤后变化基本相似。同样，损伤后血清和肌内炎症指数（e.例如，在一个实施例中，TNF-α和单核细胞趋化蛋白-1）和血管生成（e.例如，在一个实施例中，VEGF和激酶插入结构域受体）在组间无显著差异。这些发现表明，体力活动的减少和合并症的增加可能导致与年龄相关的主动肌肉再生障碍，而不是衰老本身。
Repair of skeletal muscle after injury is a key aspect of maintaining proper musculoskeletal function. Studies have suggested that regenerative processes, including myogenesis and angiogenesis, are impaired during advanced age, but evidence from humans is limited. This study aimed to compare active muscle regeneration between healthy young and older adults. We evaluated changes in clinical, biochemical, and immunohistochemical indices of muscle regeneration at precisely 2 (T2) and 7 (T3) days following acute muscle injury. Men and women, aged 18-30 and >= 70 years, matched for gender and body mass index, performed 150 unilateral, eccentric contractions of the plantar flexors at 110% of one repetition maximum. Data were analyzed using analysis of covariance, adjusted for gender, habitual physical activity, and baseline level of the outcome. A total of 30 young (n = 15; 22.5 +/- 3.7 yr) and older (n = 15; 75.8 +/- 5.0 yr) adults completed the study. Following muscle injury, force production declined 16% and 14% in young and older adults, respectively, by T2 and in each group, returned to 93% of baseline strength by T3. Despite modest differences in the pattern of response, postinjury changes in intramuscular concentrations of myogenic growth factors and number of myonuclear (4',6-diamidino-2-phenylindole+ and paired box 7+) cells were largely similar between groups. Likewise, postinjury changes in serum and intramuscular indices of inflammation (e. g., TNF-alpha and monocyte chemoattractant protein-1) and angiogenesis (e. g., VEGF and kinase insert domain receptor) did not differ significantly between groups. These findings suggest that declines in physical activity and increased co-morbidity may contribute to age-related impairments in active muscle regeneration rather than aging per se.