Exercise and Nutrition Research Program, Mary Mackillop Institute for Health Research, Australian Catholic University, Melbourne 3000, Australia.
Department of Health and Medical Sciences, Swinburne University of Technology, Melbourne 3122, Australia.
Int J Mol Sci. 2020 Jan 23;21(3):745. doi: 10.3390/ijms21030745.
Estrogen (E2) and polyunsaturated fatty acids (n-3PUFA) supplements independently support general wellbeing and enhance muscle regeneration in-vivo and myotube formation in-vitro. However, the combined effect of E2 and n-3PUFA on myoblast differentiation is not known. The purpose of the study was to identify whether E2 and n-3PUFA possess a synergistic effect on in-vitro myogenesis. Mouse C2C12 myoblasts, a reliable model to reiterate myogenic events in-vitro, were treated with 10nM E2 and 50μM eicosapentaenoic acid (EPA) independently or combined, for 0-24 h or 0-120 h during differentiation. Immunofluorescence, targeted qPCR and next generation sequencing (NGS) were used to characterize morphological changes and differential expression of key genes involved in the regulation of myogenesis and muscle function pathways. E2 increased estrogen receptor α (Erα) and the expression of the mitogen-activated protein kinase 11 (Mapk11) within 1 h of treatment and improved myoblast differentiation and myotube formation. A significant reduction ( < 0.001) in myotube formation and in the expression of myogenic regulatory factors Mrfs (, and ) and the myoblast fusion related gene, , was observed in the presence of EPA and the combined E2/EPA treatment. Additionally, EPA treatment at 48 h of differentiation inhibited the majority of genes associated with the myogenic and striated muscle contraction pathways. In conclusion, EPA and E2 had no synergistic effect on myotube formation in-vitro. Independently, EPA inhibited myoblast differentiation and overrides the stimulatory effect of E2 when used in combination with E2.
雌激素（E2）和多不饱和脂肪酸（n-3PUFA）补充剂各自支持整体健康，并增强体内肌肉再生和体外肌管形成。然而，E2 和 n-3PUFA 对成肌细胞分化的联合作用尚不清楚。本研究的目的是确定 E2 和 n-3PUFA 是否对体外肌发生具有协同作用。C2C12 成肌细胞是体外重复肌发生事件的可靠模型，用 10nM E2 和 50μM 二十碳五烯酸（EPA）分别或联合处理，在分化过程中处理 0-24 小时或 0-120 小时。免疫荧光、靶向 qPCR 和下一代测序（NGS）用于表征形态变化和参与肌发生和肌肉功能途径调节的关键基因的差异表达。E2 在治疗后 1 小时内增加雌激素受体 α（Erα）和丝裂原活化蛋白激酶 11（Mapk11）的表达，并改善成肌细胞分化和肌管形成。在 EPA 存在下和联合 E2/EPA 处理时，观察到肌管形成和肌生成调节因子 Mrfs（、和）和成肌融合相关基因的表达显著减少（<0.001）。此外，在分化的 48 小时时，EPA 处理抑制了与肌发生和横纹肌收缩途径相关的大多数基因。总之，E2 和 EPA 对体外肌管形成没有协同作用。独立地，EPA 抑制成肌细胞分化，并在与 E2 联合使用时覆盖 E2 的刺激作用。
