Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan.
Physiol Res. 2021 Mar 17;70(1):55-65. doi: 10.33549/physiolres.934534. Epub 2021 Jan 14.
This study aimed to examine the effect of eicosapentaenoic acid (EPA) on skeletal muscle hypertrophy induced by muscle overload and the associated intracellular signaling pathways. Male C57BL/6J mice were randomly assigned to oral treatment with either EPA or corn oil for 6 weeks. After 4 weeks of treatment, the gastrocnemius muscle of the right hindlimb was surgically removed to overload the plantaris and soleus muscles for 1 or 2 weeks. We examined the effect of EPA on the signaling pathway associated with protein synthesis using the soleus muscles. According to our analysis of the compensatory muscle growth, EPA administration enhanced hypertrophy of the soleus muscle but not hypertrophy of the plantaris muscle. Nevertheless, EPA administration did not enhance the expression or phosphorylation of Akt, mechanistic target of rapamycin (mTOR), or S6 kinase (S6K) in the soleus muscle. In conclusion, EPA enhances skeletal muscle hypertrophy, which can be independent of changes in the AKT-mTOR-S6K pathway.
本研究旨在探讨二十碳五烯酸（EPA）对肌肉超负荷诱导的骨骼肌肥大的影响及其相关的细胞内信号通路。雄性 C57BL/6J 小鼠被随机分为口服 EPA 或玉米油治疗 6 周。治疗 4 周后，右侧后肢的腓肠肌被手术切除，以超负荷比目鱼肌和跖肌 1 或 2 周。我们使用比目鱼肌研究了 EPA 对与蛋白质合成相关的信号通路的影响。根据对代偿性肌肉生长的分析，EPA 给药增强了比目鱼肌的肥大，但没有增强比目鱼肌的肥大。然而，EPA 给药并没有增强比目鱼肌中 Akt、雷帕霉素靶蛋白（mTOR）或 S6 激酶（S6K）的表达或磷酸化。总之，EPA 增强了骨骼肌肥大，这可能与 AKT-mTOR-S6K 通路的变化无关。
