Department of Environmental Health, School of Public Health, China Medical University, Shenyang, China.
Environ Toxicol. 2022 Feb;37(2):282-298. doi: 10.1002/tox.23397. Epub 2021 Nov 5.
Excessive manganese (Mn) exposure can cause nerve damage and mitochondrial dysfunction, which may involve defects in mitochondrial dynamics. Resveratrol (RSV) exerts a wide range of beneficial effects via activation of sirtuin 1 (SIRT1) and thus may positively impact Mn-induced mitochondrial damage through the regulation of peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) by SIRT1. In this study, we investigated the molecular mechanisms by which RSV alleviates the nerve injury and mitochondrial fragmentation caused by Mn in C57 BL/6 mice. Our results demonstrated that RSV activated the deacetylase activity of SIRT1 and protected against the surge of mitochondrial reactive oxygen species, the loss of mitochondrial membrane potential, and the attenuation of ATP caused by Mn. RSV, therefore, inhibits mitochondrial fragmentation and safeguards neural cells. Increased deacetylase activity led to a reduction in the acetylation of PGC-1α, which directly regulates DRP1 expression by binding to the DRP1 promoter. The resultant attenuation of DRP1-mediated mitochondrial fragmentation in RSV-pretreated mice was abolished by the addition of the SIRT1 inhibitor EX527. Taken together, these findings indicate that RSV alleviates Mn-induced mitochondrial dysfunction mediated by DRP1 by modulating the SIRT1/PGC-1α signaling pathway.
过量锰(Mn)暴露可导致神经损伤和线粒体功能障碍,这可能涉及线粒体动力学缺陷。白藜芦醇(RSV)通过激活沉默调节蛋白 1(SIRT1)发挥广泛的有益作用,因此可能通过 SIRT1 对过氧化物酶体增殖物激活受体-γ共激活因子 1-α(PGC-1α)的调节对 Mn 诱导的线粒体损伤产生积极影响。在这项研究中,我们研究了 RSV 通过 SIRT1 减轻 C57BL/6 小鼠中 Mn 引起的神经损伤和线粒体碎片化的分子机制。我们的结果表明,RSV 激活了 SIRT1 的去乙酰化酶活性,可防止 Mn 引起的线粒体活性氧激增、线粒体膜电位丧失和 ATP 减少。因此,RSV 抑制线粒体碎片化并保护神经细胞。去乙酰化酶活性的增加导致 PGC-1α 的乙酰化减少,PGC-1α 通过与 DRP1 启动子结合直接调节 DRP1 的表达。在 RSV 预处理的小鼠中,加入 SIRT1 抑制剂 EX527 可消除 DRP1 介导的线粒体碎片化的衰减。总之,这些发现表明 RSV 通过调节 SIRT1/PGC-1α 信号通路来减轻 Mn 诱导的 DRP1 介导的线粒体功能障碍。