Fan Heng, Le Jian-Wei, Sun Min, Zhu Jian-Hua
Department of Intensive Care Unit, The First Affiliated Hospital of Ningbo University, Ningbo, Zhejiang Province, P.R China.
Iran J Basic Med Sci. 2024;27(7):850-856. doi: 10.22038/IJBMS.2024.72882.15853.
To investigate the protective effect of N-acetylcysteine (NAC) on septic acute kidney injury (SAKI) via regulating Sirtuin3 (SIRT3)-mediated mitochondrial dysfunction and apoptosis.
By constructing SIRT3 knockout mice and culturing kidney tubular epithelial cells (KTECs), we assessed the changes of renal function and detected the protein expression of adenine nucleotide translocator (ANT), cyclophilin (CypD) and voltage-dependent anion channel (VDAC) using western-blotting, and simultaneously detected toll-like receptor 4 (TLR4), inhibitor of kappa B kinase (IKKβ), inhibitor of Kappa Bα (IκBα), and p65 protein expression. We observed mitochondrial damage of KTECs using a transmission electron microscope and assessed apoptosis by TdT-mediated dUTP Nick-End Labeling and flow cytometry.
SIRT3 deficiency led to the deterioration of renal function, and caused a significant increase in inducible nitric oxide synthase production, a decrease in mitochondrial volume, up-regulation of TLR4, IκBα, IKKβ, and p65 proteins, and up-regulation of ANT, CypD and VDAC proteins. However, NAC significantly improved renal function and down-regulated the expression of TLR4, IκBα, IKKβ, and p65 proteins. Furthermore, SIRT3 deficiency led to a significant increase in KTEC apoptosis, while NAC up-regulated the expression of SIRT3 and inhibited apoptosis.
NAC has a significant protective effect on SAKI by inhibiting SIRT3-mediated mitochondrial dysfunction and apoptosis of KTECs.
探讨N-乙酰半胱氨酸（NAC）通过调节沉默调节蛋白3（SIRT3）介导的线粒体功能障碍和细胞凋亡对脓毒症急性肾损伤（SAKI）的保护作用。
通过构建SIRT3基因敲除小鼠并培养肾小管上皮细胞（KTECs），我们评估了肾功能的变化，并使用蛋白质免疫印迹法检测腺嘌呤核苷酸转位酶（ANT）、亲环蛋白（CypD）和电压依赖性阴离子通道（VDAC）的蛋白表达，同时检测Toll样受体4（TLR4）、κB激酶抑制剂（IKKβ）、κBα抑制剂（IκBα）和p65蛋白表达。我们使用透射电子显微镜观察KTECs的线粒体损伤，并通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法和流式细胞术评估细胞凋亡。
SIRT3缺乏导致肾功能恶化，诱导型一氧化氮合酶产生显著增加，线粒体体积减小，TLR4、IκBα、IKKβ和p65蛋白上调，ANT、CypD和VDAC蛋白上调。然而，NAC显著改善了肾功能，并下调了TLR4、IκBα、IKKβ和p65蛋白的表达。此外，SIRT3缺乏导致KTECs凋亡显著增加，而NAC上调了SIRT3的表达并抑制了细胞凋亡。
NAC通过抑制SIRT3介导的线粒体功能障碍和KTECs凋亡对SAKI具有显著的保护作用。
