Translational Medicine R&D Center, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518000, China.
Musculoskeletal Research Laboratory, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, SAR, 999077, China.
Adv Biol (Weinh). 2022 Dec;6(12):e2200162. doi: 10.1002/adbi.202200162. Epub 2022 Aug 26.
Treatments are lacking for sarcopenia, which is an age-related disease characterized by loss of skeletal muscle mass, strength, and/or physical performance. Icariin is a phytomolecule from herbal Epimedium, a traditional Chinese medicine widely used to treat musculoskeletal disorders for thousands of years. Here the effects of icariin against sarcopenia are investigated and the underlying mechanism is elucidated. A classic rat model of bilaterally orchiectomized (ORX) is used to induce sarcopenia. After administration for 8 weeks, compared to the control group, the forelimb grip strength, the specific tetanic forces of the soleus (SOL) and extensor digitorum longus muscle (EDL) are higher, and the fiber cross-sectional areas (CSAs) of the gastrocnemius and tibialis anterior muscle are larger in the icariin group. In addition, icariin promotes mRNA and protein expressions of myosin heavy chain (MyHC) both in SOL and EDL. Mechanistically, icariin significantly suppresses the mRNA and protein expressions of FOXO3a, atrogin-1, and MuRF-1, which are related to the degradation of myosin heavy chain. Collectively, icariin protects from sarcopenia in ORX rats characterized by enhancing grip strength and skeletal muscle contraction, as well as increasing skeletal muscle CSA by inhibiting the ubiquitination degradation of the MyHC in skeletal muscle fibers.
缺乏针对肌少症的治疗方法，肌少症是一种与年龄相关的疾病，其特征是骨骼肌质量、力量和/或身体机能下降。淫羊藿素是一种源自草药淫羊藿的植物分子，淫羊藿是一种传统中药，数千年来一直被广泛用于治疗肌肉骨骼疾病。本研究探讨了淫羊藿素对肌少症的作用，并阐明了其潜在机制。采用双侧去势（ORX）经典大鼠模型诱导肌少症。给药 8 周后，与对照组相比，淫羊藿素组的前肢握力、比目鱼肌（SOL）和趾长伸肌（EDL）的特定强直力更高，腓肠肌和胫骨前肌的纤维横截面积（CSA）更大。此外，淫羊藿素促进了 SOL 和 EDL 中肌球蛋白重链（MyHC）的 mRNA 和蛋白表达。从机制上讲，淫羊藿素显著抑制了与肌球蛋白重链降解相关的 FOXO3a、atrogin-1 和 MuRF-1 的 mRNA 和蛋白表达。总之，淫羊藿素通过抑制骨骼肌纤维中 MyHC 的泛素化降解，可防止 ORX 大鼠的肌少症，表现为握力和骨骼肌收缩增强，以及骨骼肌 CSA 增加。
