Kamal Khaled Y, Trombetta-Lima Marina
Department of Kinesiology, Iowa State University, Ames, IA 50011, USA.
Department of Pharmaceutical Technology and Biopharmacy, Groningen Research Institute of Pharmacy, University of Groningen, 9700 Groningen, The Netherlands.
Int J Mol Sci. 2025 Mar 20;26(6):2802. doi: 10.3390/ijms26062802.
Mechanical unloading leads to profound musculoskeletal degeneration, muscle wasting, and weakness. Understanding the specific signaling pathways involved is essential for uncovering effective interventions. This review provides new perspectives on mechanotransduction pathways, focusing on the critical roles of focal adhesions (FAs) and oxidative stress in skeletal muscle atrophy under mechanical unloading. As pivotal mechanosensors, FAs integrate mechanical and biochemical signals to sustain muscle structural integrity. When disrupted, these complexes impair force transmission, activating proteolytic pathways (e.g., ubiquitin-proteasome system) that accelerate atrophy. Oxidative stress, driven by mitochondrial dysfunction and NADPH oxidase-2 (NOX2) hyperactivation, exacerbates muscle degeneration through excessive reactive oxygen species (ROS) production, impaired repair mechanisms, and dysregulated redox signaling. The interplay between FA dysfunction and oxidative stress underscores the complexity of muscle atrophy pathogenesis: FA destabilization heightens oxidative damage, while ROS overproduction further disrupts FA integrity, creating a self-amplifying vicious cycle. Therapeutic strategies, such as NOX2 inhibitors, mitochondrial-targeted antioxidants, and FAK-activating compounds, promise to mitigate muscle atrophy by preserving mechanotransduction signaling and restoring redox balance. By elucidating these pathways, this review advances the understanding of muscle degeneration during unloading and identifies promising synergistic therapeutic targets, emphasizing the need for combinatorial approaches to disrupt the FA-ROS feedback loop.
机械卸载会导致严重的肌肉骨骼退化、肌肉萎缩和无力。了解其中涉及的特定信号通路对于找到有效的干预措施至关重要。本综述提供了关于机械转导通路的新观点,重点关注粘着斑(FAs)和氧化应激在机械卸载引起的骨骼肌萎缩中的关键作用。作为关键的机械传感器,粘着斑整合机械和生化信号以维持肌肉结构完整性。当这些复合物被破坏时,会损害力的传递,激活加速萎缩的蛋白水解途径(如泛素-蛋白酶体系统)。由线粒体功能障碍和NADPH氧化酶-2(NOX2)过度激活驱动的氧化应激,通过过量产生活性氧(ROS)、损害修复机制和使氧化还原信号失调,加剧肌肉退化。粘着斑功能障碍与氧化应激之间的相互作用突显了肌肉萎缩发病机制的复杂性:粘着斑不稳定会加剧氧化损伤,而ROS的过度产生会进一步破坏粘着斑的完整性,从而形成一个自我放大的恶性循环。诸如NOX2抑制剂、线粒体靶向抗氧化剂和FAK激活化合物等治疗策略,有望通过保留机械转导信号和恢复氧化还原平衡来减轻肌肉萎缩。通过阐明这些通路,本综述增进了对卸载过程中肌肉退化的理解,并确定了有前景的协同治疗靶点,强调了采用联合方法破坏粘着斑-ROS反馈回路的必要性。