PDF(Pubmed)
Abstract：
Gracilaria chorda (GC) is a red algal species that is primarily consumed in Asia. Here, we investigated the effect of GC on obesity-related skeletal muscle wasting. Furthermore, elucidating its impact on the activation of sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) constituted a critical aspect in understanding the underlying mechanism of action. In this study, 6-week-old male C57BL/6 mice were fed a high-fat diet (HFD) for 8 weeks to induce obesity, then continued on the HFD for another 8 weeks while orally administered GC. GC decreased ectopic fat accumulation in skeletal muscle and increased muscle weight, size, and function in obese mice. Furthermore, GC reduced skeletal muscle atrophy and increased hypertrophy in mice. We hypothesized that the activation of SIRT1/PGC1α by GC regulates skeletal muscle atrophy and hypertrophy. We observed that GC increased the expression of SIRT1 and PGC1α in skeletal muscle of mice and in C2C12 cells, which increased mitochondrial function and biogenesis. In addition, when C2C12 cells were treated with the SIRT1-specific inhibitor EX-527, no changes were observed in the protein levels of SIRT1 and PGC1α in the GC-treated C2C12 cells. Therefore, GC attenuated obesity-related muscle wasting by improving mitochondrial function and biogenesis through the activation of SIRT1/PGC1α in the skeletal muscle of mice.
摘要：
Gracilariachorda（GC）是一种红色藻类，主要在亚洲消费。这里,我们研究了GC对肥胖相关骨骼肌消耗的影响。此外，阐明其对沉默酶1（SIRT1）/过氧化物酶体增殖物激活受体γ共激活因子1α（PGC1α）激活的影响是理解潜在作用机制的关键方面。在这项研究中,6周龄的雄性C57BL/6小鼠饲喂高脂饮食（HFD）8周以诱导肥胖，然后继续在HFD上另外8周,同时口服GC。GC减少了骨骼肌中的异位脂肪积累，增加了肌肉重量，尺寸,和肥胖小鼠的功能。此外，GC减少小鼠骨骼肌萎缩和增加肥大。我们假设GC激活SIRT1/PGC1α调节骨骼肌萎缩和肥大。我们观察到GC增加小鼠骨骼肌和C2C12细胞中SIRT1和PGC1α的表达,增加线粒体功能和生物发生。此外,当用SIRT1特异性抑制剂EX-527处理C2C12细胞时,在GC处理的C2C12细胞中没有观察到SIRT1和PGC1α的蛋白水平的变化。因此,GC通过激活小鼠骨骼肌中SIRT1/PGC1α来改善线粒体功能和生物发生，从而减轻肥胖相关的肌肉消耗。
