The purpose of this investigation was to evaluate the effects of aging and lifelong exercise on skeletal muscle components of the innate immune system. Additionally, the effects of an acute resistance exercise (RE) challenge were explored. Three groups of men were studied: young exercisers (YE, n=10, 25±1y, VO₂max:53±3mL/kg/min, quadriceps size:78±3cm²), lifelong aerobic exercisers with a 53±1y training history (LLE, n=21, 74±1y, VO₂max:34±1 mL/kg/min, quadriceps size:67±2cm²), and old healthy non-exercisers (OH, n=10, 75±1y, VO₂max:22±1mL/kg/min, quadriceps size:56±3cm²). Vastus lateralis muscle biopsies were obtained in the basal state and 4h after RE (3x10reps, 70%1RM) to assess Toll-like receptors (TLR)1-10, TLR adaptors (Myd88 and TRIF), and NFκB pathway components (IκΒα and IKKβ) mRNA expression. Basal TLR3, TLR6, and TLR7 tended to be higher (P≤0.10) with aging (LLE and OH combined). In general, RE increased expression of TLR1 and TLR8 (P≤0.10) and TLR3 and TLR4 (P<0.05), although TLR3 did not respond in OH. Both TLR adaptors also responded to the exercise bout; these were primarily (Myd88, main effect P≤0.10) or exclusively (TRIF, P<0.05) driven by the OH group. In summary, aging appears to increase basal expression of some innate immune components in human skeletal muscle, and lifelong aerobic exercise does not affect this age-related increase. An exercise challenge stimulates the expression of several TLRs, while the TLR adaptor response appears to be dysregulated with aging and maintained with lifelong exercise. Partially preserved muscle mass, coupled with a notable immunity profile, suggests lifelong exercisers are likely better prepared for a stress that challenges the immune system.

中文翻译：

---

衰老和终身有氧运动对人体骨骼肌先天免疫成分表达的影响。

本次调查的目的是评估衰老和终生锻炼对先天免疫系统骨骼肌成分的影响。此外，还探讨了急性阻力运动 (RE) 挑战的影响。研究了三组男性：年轻锻炼者（YE，n=10, 25±1y，VO ₂ max：53±3mL/kg/min，股四头肌大小：78±3cm ²），终生有氧锻炼者，训练时间为 53±1y病史 (LLE, n=21, 74±1y, VO ₂ max:34±1 mL/kg/min, 四头肌大小:67±2cm ² ), 和不锻炼的老年健康者 (OH, n=10, 75±1y , VO ₂ max:22±1mL/kg/min, 股四头肌大小:56±3cm ²）。在基础状态和 RE (3x10reps, 70%1RM) 后 4 小时获得股外侧肌活检，以评估 Toll 样受体 (TLR)1-10、TLR 接头（Myd88 和 TRIF）和 NFκB 通路成分（IκΒα 和 IKKβ） ) mRNA 表达。随着年龄的增长（LLE 和 OH 结合），基础 TLR3、TLR6 和 TLR7 往往更高（P≤0.10）。一般而言，RE 增加了 TLR1 和 TLR8（P≤0.10）以及 TLR3 和 TLR4（P<0.05）的表达，尽管 TLR3 在 OH 中没有反应。两个 TLR 适配器也响应了练习回合；这些主要（Myd88，主效应 P≤0.10）或完全（TRIF，P<0.05）由 OH 基团驱动。总之，衰老似乎会增加人类骨骼肌中某些先天免疫成分的基础表达，终身有氧运动不会影响这种与年龄相关的增加。运动挑战会刺激几种 TLR 的表达，而 TLR 适配器反应似乎随着年龄的增长而失调，并通过终生锻炼得以维持。部分保留的肌肉质量，加上显着的免疫特征，表明终生锻炼者可能为挑战免疫系统的压力做好了更好的准备。