Department of Herbology, College of Korean Medicine, Dongguk University, Gyeongju 38066, Korea.
Korean Medicine R&D Center, Dongguk University, Gyeongju 38066, Korea.
Molecules. 2018 Aug 13;23(8):2023. doi: 10.3390/molecules23082023.
With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.
随着衰老过程的进行，老年人会出现骨骼肌质量下降和与代谢综合征相关的功能障碍。山药常用于具有各种作用的功能性食品和药物。本研究旨在探讨山药根茎提取物及其生物活性化合物尿囊素对骨骼肌细胞成肌分化和线粒体生物发生的影响。山药用水提取，尿囊素用高效液相色谱法（HPLC）分析。通过逆转录（RT）-聚合酶链反应（RT-PCR）或 Western blot 测定 C2C12 肌管中肌球蛋白重链（MyHC）和线粒体生物发生调节因子过氧化物酶体增殖物激活受体γ共激活因子 1-α（PGC-1α）、沉默调节蛋白 1（Sirt-1）、核呼吸因子-1（NRF-1）和转录因子 A，线粒体（TFAM）的表达以及 AMP 激活的蛋白激酶（AMPK）和乙酰辅酶 A 羧化酶（ACC）的磷酸化。通过葡萄糖消耗、葡萄糖摄取和 ATP 测定分别测量葡萄糖水平和总 ATP 含量。山药提取物（1mg/mL）和尿囊素（0.2 和 0.5mM）处理与未经处理的肌管相比，MyHC 表达显著增加。山药提取物和尿囊素显著增加了 PGC-1α、Sirt-1、NRF-1 和 TFAM 的表达，以及 C2C12 肌管中 AMPK 和 ACC 的磷酸化。此外，山药提取物和尿囊素显著增加了葡萄糖摄取水平和 ATP 含量。最后，HPLC 分析表明，山药水提取物含有 1.53%的尿囊素。山药提取物和尿囊素通过上调线粒体生物发生调节剂刺激成肌细胞向肌管分化，并增加能量产生。这些发现表明，山药提取物和尿囊素可以通过刺激能量代谢来帮助预防骨骼肌功能障碍。
