Muscle atrophy and skeletal muscle fibrosis are significant pathological manifestations of primary sarcopenia. The regulation of C2C12 myoblast and skeletal muscle fibroblast apoptosis is associated with these pathological changes. Previous studies have indicated that irisin, the cleaved form of fibronectin type III domain-containing protein 5 (FNDC5), can alleviate primary sarcopenia. However, the mechanisms of the effect of irisin in age-related apoptosis remain unknown. Our present research aimed to explore the effect of irisin and the underlying mechanism of d-galactose (d-gal)-induced apoptosis in skeletal muscle fibroblasts and C2C12 myoblasts. We found the opposite effects of d-gal on C2C12 myoblasts and fibroblasts. We also found that irisin suppressed C2C12 cell apoptosis and promoted fibroblast apoptosis. Mechanistically, irisin altered d-gal-induced apoptosis by increasing caveolin-1 expression. Taken together, these findings further demonstrated that irisin is a potential agent that can treat aged-relative muscle atrophy and fibrosis.

肌肉萎缩和骨骼肌纤维化是原发性肌少症的重要病理表现。 C2C12成肌细胞和骨骼肌成纤维细胞凋亡的调节与这些病理变化相关。先前的研究表明，鸢尾素（纤连蛋白 III 型结构域蛋白 5 (FNDC5) 的切割形式）可以缓解原发性肌少症。然而，鸢尾素在年龄相关细胞凋亡中的作用机制仍不清楚。我们目前的研究旨在探讨鸢尾素的作用以及d-半乳糖（d -gal）诱导骨骼肌成纤维细胞和C2C12成肌细胞凋亡的潜在机制。我们发现d -gal 对 C2C12 成肌细胞和成纤维细胞具有相反的作用。我们还发现鸢尾素抑制 C2C12 细胞凋亡并促进成纤维细胞凋亡。从机制上讲，鸢尾素通过增加 Caveolin-1 的表达来改变d -gal 诱导的细胞凋亡。总而言之，这些发现进一步证明鸢尾素是一种可以治疗老年肌肉萎缩和纤维化的潜在药物。