【摘要】 旨在探索硒代蛋氨酸羟基类似物（SeOH）缓解鸡肝癌细胞（LMH）氧化损伤的作用及潜在机制。建立H₂O₂氧化应激模型，通过检测细胞活力和细胞氧化/抗氧化指标的变化以及核转录因子E2相关因子2 （Nrf₂）通路和内质网应激关键分子的表达情况，评价不同浓度SeOH（16、32和64μg/mL）的抗氧化应激和内质网应激作用。结果显示：120μmol/L的H₂O₂刺激细胞24 h时，细胞活力显著下降（P<0.001）,活性氧（ROS）的荧光强度升高。不同剂量的SeOH（16、32和64μg/mL）均可显著提高H₂O₂处理后的LMH细胞活力（P<0.01）;32和64μg/mL的SeOH均可极显著提高LMH细胞的超氧化物歧化酶（SOD）活性（P<0.01）,显著降低丙二醛（MDA）含量（P<0.001）以及ROS的荧光强度。进一步研究显示32和64μg/mL的SeOH极显著上调Nrf₂蛋白（P<0.01）并显著上调谷胱甘肽过氧化物酶4（GPX4）蛋白的表达水平（P<0.05）,极显著下调Kelch样ECH相关蛋白1（Keap1）蛋白的表达水平（P<0.001）,极显著增加Nrf₂的入核率（P<0.001）;64μg/mL的SeOH可显著降低葡萄糖调节蛋白78（GRP78）（P<0.05）、蛋白激酶RNA样内质网激酶（PERK）（P<0.01）和转录激活因子4（ATF4）（P<0.001）的表达水平。提示：SeOH能通过激活Nrf₂通路并且抑制内质网应激缓解H₂O₂诱导的LMH细胞氧化应激，为畜禽养殖中SeOH作为抗氧化剂的应用提供理论基础。更多还原

【Abstract】 The aim of this study was to explore the effect and potential mechanism of hydroxy-selenomethionine（SeOH） on oxidative damage of chicken hepatocellular carcinoma cells（LMH）. An H₂O₂ oxidative stress model was established to evaluate the effects of different concentrations of SeOH（16, 32 and 64 μg/mL） on oxidative stress and ER stress by detecting the changes in cell viability and cell oxidation/antioxidant indexes, as well as the expression of the nuclear factor erythroid-related factor 2（Nrf₂） pathway and the key molecules of ER stress. The results showed that cell viability significantly decreased（P<0.001） and the fluorescence intensity of ROS increased, indicating that the H₂O₂-induced（120 μmol/L, for 24 h） oxidative stress model was successfully established. The different concentrations of SeOH（16, 32 and 64 μg/mL） significantly enhanced the cell viability（P<0.01）. Both 32 and 64 μg/mL SeOH significantly promoted the activity of superoxide dismutase（SOD） in the LMH cells（P<0.01）, significantly reduced the content of malondialdehyde（MDA）（P<0.001） and the production of fluorescence intensity of ROS in the LMH cells. Further research showed that SeOH（32 and 64 μg/mL） significantly up-regulated the protein expression level of Nrf₂（P<0.01） and glutathione peroxidase 4（GPX4）（P<0.05）, and down-regulated the expression level of Kelch-like ECH-associated protein 1（Keap1）（P<0.001）, and synergistically promoted the efficiency of nuclear translocation of Nrf2（P<0.001）. However, the protein expression levels of GRP78（P<0.05）, PERK（P<0.01） and ATF4（P<0.001） were significantly decreased under the 64 μg/mL SeOH treatment. In conclusion, SeOH relieved H₂O₂-induced oxidative stress in LMH cells by activating the Nrf₂ pathway and inhibiting ER stress. This study provided a theoretical basis for the application of SeOH as an antioxidant in livestock and poultry industries.更多还原