Transcriptomic analysis of porcine muscle Biceps femoris (BF) exposed to a single bout of endurance exercise. Sus scrofa

Acute physical exercise elicits changes in gene expression in skeletal muscles to promote metabolic changes and to repair exercise-induced muscle injuries. Here, we investigated the impact of a single bout of running exercise until exhaustion on global transcriptional profiles in porcine skeletal muscles. Using a combined microarray and candidate gene approach, we identified a suite of genes that are differentially expressed in muscles during post-exercise recovery. Thus, several members of the heat shock protein family and proteins associated with proteolytic events were significantly up-regulated, suggesting that protein breakdown, prevention of protein aggregation and stabilization of unfolded proteins are important processes for restoring cellular homeostasis. We also detected an up-regulation of genes, which have been reported to be associated with muscle cell proliferation and differentiation, possibly reflecting an activation, differentiation and fusion of satellite cells to facilitate repair of muscle damage. In addition, exercise increased expression of the nuclear hormone receptors, which regulates metabolic functions associated with lipid, carbohydrate and energy homeostasis. Finally, we observed an unanticipated involvement of long non-coding RNA transcripts, which have been implicated in RNA processing and nuclear retention of adenosine-to-inosine edited mRNAs. These findings expand the complexity of pathways affected by acute contractile activity of skeletal muscle, contributing to a better understanding of the molecular processes that occur in muscle tissue in the recovery phase. Overall design: Gene expression study of the porcine muscle Biceps femoris in regard to exercise, pigs allowed to rest for 0 hours, 1 hour and 3 hours after exercise were compared with pigs that had not been exercising, using in-house printed porcine two-colour oligonucleotide microarrays.

急性运动可诱导骨骼肌基因表达发生改变，以促进代谢变化并修复运动诱发的肌肉损伤。本研究探讨了单次力竭跑步运动对猪骨骼肌全局转录谱的影响。我们结合微阵列（microarray）与候选基因研究策略，鉴定出运动后恢复阶段骨骼肌中差异表达的一系列基因。结果显示，热休克蛋白家族多个成员及与蛋白水解过程相关的蛋白均显著上调，提示蛋白降解、抑制蛋白聚集以及稳定未折叠蛋白是恢复细胞稳态的重要生物学过程。我们还检测到与肌细胞增殖分化相关的基因出现上调，这可能反映了肌卫星细胞的激活、分化与融合，从而促进肌肉损伤修复。此外，运动可上调核激素受体的表达，该受体可调控与脂质、碳水化合物及能量稳态相关的代谢功能。最后，我们观察到长链非编码RNA（long non-coding RNA）转录本存在未预期的参与作用，这类RNA此前被证实参与RNA加工以及腺苷-肌苷（adenosine-to-inosine）编辑mRNA的核滞留过程。本研究结果拓展了骨骼肌急性收缩活动所影响的通路复杂性，有助于更深入理解肌肉组织在恢复阶段发生的分子过程。
整体实验设计：以猪股二头肌（Biceps femoris）为研究对象开展基因表达研究，将运动后分别休息0小时、1小时及3小时的实验猪与未运动的对照组猪进行比较，采用实验室自制的猪双色寡核苷酸微阵列进行基因表达检测。