Laboratory of Biochemistry and Molecular Biology, Department of Movement, Human and Health Sciences, Università degli Studi di Roma "Foro Italico", 00135 Rome, Italy.
Department of Science, "Department of Excellence 2018-2022", University of Rome "Roma Tre", 00146 Rome, Italy.
Int J Mol Sci. 2022 Sep 20;23(19):10986. doi: 10.3390/ijms231910986.
A central feature of the skeletal muscle is its ability to regenerate through the activation, by environmental signals, of satellite cells. Once activated, these cells proliferate as myoblasts, and defects in this process profoundly affect the subsequent process of regeneration. High levels of reactive oxygen species such as hydrogen peroxide (HO) with the consequent formation of oxidized macromolecules increase myoblasts' cell death and strongly contribute to the loss of myoblast function. Recently, particular interest has turned towards the beneficial effects on muscle of the naturally occurring polyamine spermidine (Spd). In this work, we tested the hypothesis that Spd, upon oxidative challenge, would restore the compromised myoblasts' viability and redox status. The effects of Spd in combination with aminoguanidine (Spd-AG), an inhibitor of bovine serum amine oxidase, on murine C2C12 myoblasts treated with a mild dose of HO were evaluated by analyzing: (i) myoblast viability and recovery from wound scratch; (ii) redox status and (iii) polyamine (PAs) metabolism. The treatment of C2C12 myoblasts with Spd-AG increased cell number and accelerated scratch wound closure, while HO exposure caused redox status imbalance and cell death. The combined treatment with Spd-AG showed an antioxidant effect on C2C12 myoblasts, partially restoring cellular total antioxidant capacity, reducing the oxidized glutathione (GSH/GSSG) ratio and increasing cell viability through a reduction in cell death. Moreover, Spd-AG administration counteracted the induction of polyamine catabolic genes and PA content decreased due to HO challenges. In conclusion, our data suggest that Spd treatment has a protective role in skeletal muscle cells by restoring redox balance and promoting recovery from wound scratches, thus making myoblasts able to better cope with an oxidative insult.
骨骼肌的一个主要特征是，它能够通过环境信号激活卫星细胞来进行再生。一旦被激活，这些细胞就会增殖成为成肌细胞，而这个过程中的缺陷会严重影响随后的再生过程。高水平的活性氧物质，如过氧化氢（HO），以及随之形成的氧化大分子，会增加成肌细胞的死亡，并强烈导致成肌细胞功能的丧失。最近，人们对天然多胺亚精胺（Spd）对肌肉的有益作用特别感兴趣。在这项工作中，我们假设 Spd 在氧化应激下会恢复受损成肌细胞的活力和氧化还原状态。通过分析（i）成肌细胞活力和划痕愈合恢复；（ii）氧化还原状态和（iii）多胺（PAs）代谢，来评估 Spd 与牛血清胺氧化酶抑制剂氨基胍（Spd-AG）联合处理用低剂量 HO 处理的鼠 C2C12 成肌细胞的效果。Spd-AG 处理 C2C12 成肌细胞可增加细胞数量并加速划痕伤口闭合，而 HO 暴露会导致氧化还原状态失衡和细胞死亡。Spd-AG 的联合治疗对 C2C12 成肌细胞表现出抗氧化作用，部分恢复细胞总抗氧化能力，降低氧化型谷胱甘肽（GSH/GSSG）比值，并通过减少细胞死亡来增加细胞活力。此外，Spd-AG 给药可抑制多胺分解代谢基因的诱导，并降低由于 HO 挑战而导致的多胺含量。总之，我们的数据表明，Spd 处理通过恢复氧化还原平衡和促进伤口划痕的恢复，在骨骼肌细胞中发挥保护作用，从而使成肌细胞能够更好地应对氧化应激。
