Department of Public Health, Kawasaki Medical School, 577 Matsushima, Kurashiki 701-0192, Japan.
Med Sci (Basel). 2023 Feb 10;11(1):19. doi: 10.3390/medsci11010019.
Chronic stress induces psychological and physiological changes that may have negative sequelae for health and well-being. In this study, the skeletal muscles of male C57BL/6 mice subjected to repetitive water-immersion restraint stress to model chronic stress were examined. In chronically stressed mice, serum corticosterone levels significantly increased, whereas thymus volume and bone mineral density decreased. Further, body weight, skeletal muscle mass, and grip strength were significantly decreased. Histochemical analysis of the soleus muscles revealed a significant decrease in the cross-sectional area of type 2b muscle fibers. Although type 2a fibers also tended to decrease, chronic stress had no impact on type 1 muscle fibers. Chronic stress increased the expression of and , but did not affect the expression of or . In contrast, chronic stress resulted in a decrease in p-S6 and p-4E-BP1 levels in the soleus muscle. Taken together, these results indicate that chronic stress promotes muscle atrophy by inhibiting mammalian targets of rapamycin complex 1 activity due to the upregulation of its inhibitor, .
慢性应激会引起心理和生理变化，可能对健康和幸福产生负面影响。在这项研究中，我们观察了雄性 C57BL/6 小鼠的骨骼肌，这些小鼠经历了反复的浸水束缚应激，以模拟慢性应激。在慢性应激的小鼠中，血清皮质酮水平显著升高，而胸腺体积和骨密度下降。此外，体重、骨骼肌质量和握力显著下降。比目鱼肌的组织化学分析显示，2b 型肌纤维的横截面积显著减少。虽然 2a 型纤维也有减少的趋势，但慢性应激对 1 型肌纤维没有影响。慢性应激增加了 和 的表达，但不影响 或 的表达。相反，慢性应激导致比目鱼肌中 p-S6 和 p-4E-BP1 水平降低。综上所述，这些结果表明，慢性应激通过上调其抑制剂 来抑制雷帕霉素靶蛋白复合物 1 的活性，从而促进肌肉萎缩。
