Kang Ji Sook, Choi Il-Whan, Han Min Ho, Hong Su Hyun, Kim Sung Ok, Kim Gi-Young, Hwang Hye Jin, Kim Byung Woo, Choi Byung Tae, Kim Cheol Min, Choi Yung Hyun
Blue-Bio Industry RIC, Dongeui University, Busan, 614-714, Republic of Korea.
Department of Microbiology, College of Medicine, Inje University, Busan, 608-737, Republic of Korea.
BMC Complement Altern Med. 2015 Feb 5;15:17. doi: 10.1186/s12906-015-0538-2.
Sargassum horneri, an edible marine brown alga, is typically distributed along the coastal seas of Korea and Japan. Although several studies have demonstrated the anti-oxidative activity of this alga, the regulatory mechanisms have not yet been defined. The aim of the present study was to examine the cytoprotective effects of S. horneri against oxidative stress-induced cell damage in C2C12 myoblasts.
We demonstrated the anti-oxidative effects of a methanol extract of S. horneri (SHME) in a hydrogen peroxide (H2O2)-stimulated C2C12 myoblast model. Cytotoxicity was determined using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyl-tetrazolium assay and mode of cell death by cell cycle analysis. DNA damage was measured using a comet assay and expression of phospho-histone γH2A.X (p-γH2A.X). Levels of cellular oxidative stress as reactive oxygen species (ROS) accumulation were measured using 2',7'-dichlorofluorescein diacetate. The involvement of selected genes in the oxidative stress-mediated signaling pathway was explored using Western blot analysis.
SHME attenuated H2O2-induced growth inhibition and exhibited scavenging activity against intracellular ROS that were induced by H2O2. The SHME also inhibited comet tail formation, p-γH2A.X expression, and the number of sub-G1 hypodiploid cells, suggesting that it prevents H2O2-induced cellular DNA damage and apoptotic cell death. Furthermore, the SHME significantly enhanced the expression of heme oxygenase-1 (HO-1) associated with induction of nuclear factor-erythroid 2 related factor 2 (Nrf2) in a time- and concentration-dependent manner. Moreover, the protective effect of the SHME on H2O2-induced C2C12 cell damage was significantly abolished by zinc protoporphyrin IX, a HO-1 competitive inhibitor, in C2C12 cells.
These findings suggest that the SHME augments cellular antioxidant defense capacity through both intrinsic free radical scavenging activity and activation of the Nrf2/HO-1 pathway, protecting C2C12 cells from H2O2-induced oxidative cytotoxicity.
鼠尾藻是一种可食用的海洋褐藻，通常分布于韩国和日本沿海海域。尽管多项研究已证实该藻类具有抗氧化活性，但其调控机制尚未明确。本研究旨在探讨鼠尾藻对过氧化氢诱导的C2C12成肌细胞损伤的细胞保护作用。
我们在过氧化氢刺激的C2C12成肌细胞模型中证实了鼠尾藻甲醇提取物（SHME）的抗氧化作用。使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑盐法测定细胞毒性，并通过细胞周期分析确定细胞死亡方式。使用彗星试验和磷酸化组蛋白γH2A.X（p-γH2A.X）的表达来测量DNA损伤。使用2',7'-二氯荧光素二乙酸酯测量细胞内活性氧（ROS）积累作为细胞氧化应激水平。使用蛋白质印迹分析探索选定基因在氧化应激介导的信号通路中的参与情况。
SHME减轻了过氧化氢诱导的生长抑制，并表现出对过氧化氢诱导的细胞内ROS的清除活性。SHME还抑制了彗星尾形成、p-γH2A.X表达和亚G1期亚二倍体细胞数量，表明它可防止过氧化氢诱导的细胞DNA损伤和凋亡性细胞死亡。此外，SHME以时间和浓度依赖性方式显著增强了与核因子红细胞2相关因子2（Nrf2）诱导相关的血红素加氧酶-1（HO-1）的表达。此外，在C2C12细胞中，HO-1竞争性抑制剂原卟啉锌IX显著消除了SHME对过氧化氢诱导的C2C12细胞损伤的保护作用。
这些发现表明，SHME通过内在的自由基清除活性和Nrf2/HO-1途径的激活增强了细胞抗氧化防御能力，保护C2C12细胞免受过氧化氢诱导的氧化细胞毒性。
