Dong Daoyin, Zhong Wei, Sun Qian, Zhang Wenliang, Sun Xinguo, Zhou Zhanxiang
Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, NC, USA.
Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, NC, USA; Department of Nutrition, University of North Carolina at Greensboro, Greensboro, NC, USA.
Cytokine. 2016 Sep;85:109-19. doi: 10.1016/j.cyto.2016.06.014. Epub 2016 Jun 14.
Pro-inflammatory cytokines play a vital role in the pathogenesis of alcoholic steatohepatitis. The present study was to determine the role of alcohol-induced oxidative stress in modulating cytokine production. A rat model of alcohol consumption was used to determine alcohol-induced hepatic cytokine expression. Chronic alcohol exposure caused lipid accumulation, oxidative stress, and inflammation in the livers of Wistar rats. The role of oxidative stress in regulating cell type-specific cytokine production was further dissected in vitro. Lipopolysaccharide (LPS) dose-dependently upregulated TNF-α, MIP-1α, MCP-1, and CINC-1 in Kupffer cells-SV40, whereas TNF-α dose-dependently induced CINC-1, IP-10, and MIP-2 expression in H4IIEC3 hepatoma cells. An additive effect on cytokine production was observed in both Kupffer cells-SV40 and hepatocytes when combined hydrogen peroxide with LPS or TNF-α, respectively, which was associated with NF-κB activation and histone H3 hyper-acetylation. Unexpectedly, an inhibitory effect of 4-hydroxynonenal on cytokine production was revealed in LPS-treated Kupffer cells-SV40. Mechanistic study showed that 4-hydroxynonenal significantly enhanced mRNA degradation of TNF-α, MCP-1, and MIP-1α, and decreased the protein levels of MCP-1 in LPS-stimulated Kupffer cells-SV40 through reducing the phosphorylation of mRNA binding proteins. This study suggests that Kupffer cells and hepatocytes express distinct pro-inflammatory cytokines/chemokines in response to alcohol intoxication, and oxidative products (4-hydroxynonenal) differentially modulate pro-inflammatory cytokine/chemokine production via NF-κB signaling, histone acetylation, and mRNA stability.
促炎细胞因子在酒精性脂肪性肝炎的发病机制中起着至关重要的作用。本研究旨在确定酒精诱导的氧化应激在调节细胞因子产生中的作用。使用酒精摄入大鼠模型来确定酒精诱导的肝脏细胞因子表达。慢性酒精暴露导致Wistar大鼠肝脏脂质蓄积、氧化应激和炎症。体外进一步剖析了氧化应激在调节细胞类型特异性细胞因子产生中的作用。脂多糖(LPS)剂量依赖性上调库普弗细胞-SV40中的TNF-α、MIP-1α、MCP-1和CINC-1,而TNF-α剂量依赖性诱导H4IIEC3肝癌细胞中CINC-1、IP-10和MIP-2的表达。当过氧化氢分别与LPS或TNF-α联合时,在库普弗细胞-SV40和肝细胞中均观察到对细胞因子产生的叠加效应,这与NF-κB激活和组蛋白H3高乙酰化有关。出乎意料的是,在LPS处理的库普弗细胞-SV40中发现4-羟基壬烯醛对细胞因子产生具有抑制作用。机制研究表明,4-羟基壬烯醛通过降低mRNA结合蛋白的磷酸化,显著增强LPS刺激的库普弗细胞-SV40中TNF-α、MCP-1和MIP-1α的mRNA降解,并降低MCP-1的蛋白水平。本研究表明,库普弗细胞和肝细胞在酒精中毒时表达不同的促炎细胞因子/趋化因子,氧化产物(4-羟基壬烯醛)通过NF-κB信号传导、组蛋白乙酰化和mRNA稳定性差异调节促炎细胞因子/趋化因子的产生。