Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"-SCITEC Sede di Roma, Largo F. Vito, 00168 Roma, Italy.
Dipartimento di Scienze Biotecnologiche di Base, Cliniche Intensivologiche e Perioperatorie, Sezione di Biochimica, Università Cattolica del Sacro Cuore di Roma, Largo F. Vito 1, 00168 Roma, Italy.
Int J Mol Sci. 2023 Oct 17;24(20):15276. doi: 10.3390/ijms242015276.
Muscle weakness and muscle loss characterize many physio-pathological conditions, including sarcopenia and many forms of muscular dystrophy, which are often also associated with mitochondrial dysfunction. Verbascoside, a phenylethanoid glycoside of plant origin, also named acteoside, has shown strong antioxidant and anti-fatigue activity in different animal models, but the molecular mechanisms underlying these effects are not completely understood. This study aimed to investigate the influence of verbascoside on mitochondrial function and its protective role against HO-induced oxidative damage in murine C2C12 myoblasts and myotubes pre-treated with verbascoside for 24 h and exposed to HO. We examined the effects of verbascoside on cell viability, intracellular reactive oxygen species (ROS) production and mitochondrial function through high-resolution respirometry. Moreover, we verified whether verbascoside was able to stimulate nuclear factor erythroid 2-related factor (Nrf2) activity through Western blotting and confocal fluorescence microscopy, and to modulate the transcription of its target genes, such as heme oxygenase-1 (HO-1) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), by Real Time PCR. We found that verbascoside (1) improved mitochondrial function by increasing mitochondrial spare respiratory capacity; (2) mitigated the decrease in cell viability induced by HO and reduced ROS levels; (3) promoted the phosphorylation of Nrf2 and its nuclear translocation; (4) increased the transcription levels of HO-1 and, in myoblasts but not in myotubes, those of PGC-1α. These findings contribute to explaining verbascoside's ability to relieve muscular fatigue and could have positive repercussions for the development of therapies aimed at counteracting muscle weakness and mitochondrial dysfunction.
肌肉无力和肌肉损失是许多生理病理状况的特征，包括肌肉减少症和许多形式的肌肉营养不良症，这些疾病通常也与线粒体功能障碍有关。苯乙醇苷类化合物毛蕊花糖苷，也称为毛蕊花糖苷，在不同的动物模型中显示出很强的抗氧化和抗疲劳活性，但这些作用的分子机制尚不完全清楚。本研究旨在研究毛蕊花糖苷对线粒体功能的影响及其在 HO 诱导的氧化损伤中的保护作用，在预处理 24 小时的 C2C12 成肌细胞和肌管中加入毛蕊花糖苷，然后暴露于 HO 中。我们通过高分辨率呼吸测定法研究了毛蕊花糖苷对细胞活力、细胞内活性氧（ROS）产生和线粒体功能的影响。此外，我们通过 Western blot 和共聚焦荧光显微镜验证了毛蕊花糖苷是否能够刺激核因子红细胞 2 相关因子（Nrf2）的活性，并通过 Real Time PCR 调节其靶基因血红素加氧酶-1（HO-1）和过氧化物酶体增殖物激活受体γ共激活因子 1-α（PGC-1α）的转录。我们发现毛蕊花糖苷（1）通过增加线粒体备用呼吸能力来改善线粒体功能；（2）减轻 HO 诱导的细胞活力下降和降低 ROS 水平；（3）促进 Nrf2 的磷酸化及其核易位；（4）增加 HO-1 的转录水平，并且仅在成肌细胞中而不在肌管中增加 PGC-1α 的转录水平。这些发现有助于解释毛蕊花糖苷缓解肌肉疲劳的能力，并可能对开发旨在对抗肌肉无力和线粒体功能障碍的治疗方法产生积极影响。
