We previously demonstrated that astaxanthin (ASTX), a xanthophyll carotenoid, repressed ethanol-induced inflammation and oxidative stress in macrophages. We explored the role of sirtuin 1 (SIRT1) and histone deacetylase 4 (HDAC4) in the inhibitory effect of ASTX on inflammation and oxidative stress in macrophages exposed to ethanol. Ethanol decreased mRNA and protein of SIRT1 while increasing those of HDAC4, which was attenuated by ASTX in RAW 264.7 macrophages and mouse bone marrow-derived macrophages (BMDMs). Inhibition of SIRT1 expression or activity augmented ethanol-induced Hdac4 expression, but SIRT1 activation elicited the opposite effect. Consistently, Hdac4 knockdown increased Sirt1 expression with decreases in ethanol-induced inflammatory gene expression, but its overexpression resulted in the opposite effects. Furthermore, BMDMs from mice with macrophage specific-deletion of Hdac4 (Hdac4^MKO) showed significant decreases in ethanol-induced inflammatory genes and ROS accumulation but an increase in Sirt1 expression. Macrophage specific deletion of Hdac4 or ASTX abolished the changes in genes for mitochondrial biogenesis and glycolysis by ethanol. Ethanol increased mitochondrial respiration, ATP production, and proton leak, but decreased maximal respiration and spare respiratory capacity, all of which were abolished by ASTX in RAW 264.7 macrophages. The ethanol-induced alterations in mitochondrial respiration were abrogated in Hdac4^MKO BMDMs. In conclusion, the anti-inflammatory and antioxidant properties of ASTX in ethanol-treated macrophages may be mediated, at least partly, by its opposite effect on SIRT1 and HDAC4 to empower SIRT1 to counteract ethanol-induced activation of HDAC4.

我们以前证明了叶黄素类胡萝卜素虾青素（ASTX）可以抑制巨噬细胞中乙醇诱导的炎症和氧化应激。我们探讨了沉默调节蛋白1（SIRT1）和组蛋白脱乙酰基酶4（HDAC4）在ASTX对暴露于乙醇的巨噬细胞的炎症和氧化应激的抑制作用中的作用。乙醇降低SIRT1的mRNA和蛋白，同时增加HDAC4的mRNA和蛋白，这在RAW 264.7巨噬细胞和小鼠骨髓衍生的巨噬细胞（BMDM）中被ASTX减弱。SIRT1表达或活性的抑制增强了乙醇诱导的Hdac4表达，但SIRT1激活引起相反的作用。始终如一，HDAC4击倒增加Sirt1的乙醇诱导的炎症基因表达减少，但其过表达导致相反的作用。此外，来自具有巨噬细胞特异性缺失Hdac4（Hdac4 ^MKO）的小鼠的BMDMs在乙醇诱导的炎症基因和ROS积累中显着降低，但Sirt1表达增加。Hdac4的巨噬细胞特异性缺失或ASTX取消了乙醇引起的线粒体生物发生和糖酵解基因的变化。乙醇增加线粒体呼吸，ATP产生和质子泄漏，但最大呼吸和备用呼吸能力下降，所有这些都被RAW 264.7巨噬细胞中的ASTX废除了。Hdac4 ^MKO BMDM中消除了乙醇诱导的线粒体呼吸变化。总之，乙醇处理的巨噬细胞中ASTX的抗炎和抗氧化特性至少可以部分通过其对SIRT1和HDAC4的相反作用来介导，以赋予SIRT1抵抗乙醇诱导的HDAC4激活的能力。