Department of Toxicology, Anhui Medical University, Hefei, China.
The Second Affiliated Hospital, Anhui Medical University, Hefei, China.
Int Immunopharmacol. 2022 Jun;107:108687. doi: 10.1016/j.intimp.2022.108687. Epub 2022 Mar 10.
Our earlier studies indicated that reactive oxygen species (ROS) were involved in lipopolysaccharide (LPS)-induced acute kidney injury (AKI). The present study aimed to explore the role of mitochondria-derived ROS on renal cell ferroptosis during LPS-induced AKI. Male CD-1 mice were intraperitoneally injected with LPS (2.0 mg/kg). Renal MDA and 4HNE residue, two markers of lipid peroxidation, were increased in LPS-exposed mice. Oxidized lipids were detected in LPS-treated human HK-2 cells. In vivo, ferroptosis-characteristic ultrastructure changes, including cell volume reduction, nuclear pyknosis and smaller mitochondria, were shown in renal cortex. In vitro, abnormal alteration of mitochondrial membrane potential was observed in LPS-treated human HK-2 cells. Ferrostatin-1, a specific inhibitor of ferroptosis, attenuated LPS-evoked renal lipid peroxidation, ferroptosis-characteristic mitochondrial damage and renal cell death. Mechanistically, mitochondria-derived ROS were elevated in LPS-stimulated HK-2 cells. MitoQ, a mitochondria-targeted antioxidant, almost completely scavenged LPS-stimulated mitochondrial ROS in human HK-2 cells. Moreover, pretreatment with MitoQ attenuated LPS-induced GSH depletion and lipid peroxidation in mouse kidney. Finally, pretreatment with MitoQ alleviated LPS-induced renal cell death and AKI. Taken together, these results suggest that mitochondria-derived ROS contribute, at least partially, to renal cell ferroptosis during LPS-induced AKI. Mitochondria-targeted antioxidants may be potential therapeutic agents for sepsis-induced AKI.
我们之前的研究表明,活性氧(ROS)参与了脂多糖(LPS)诱导的急性肾损伤(AKI)。本研究旨在探讨 LPS 诱导 AKI 期间线粒体来源的 ROS 在肾小管细胞铁死亡中的作用。雄性 CD-1 小鼠腹膜内注射 LPS(2.0mg/kg)。LPS 暴露的小鼠肾 MDA 和 4HNE 残留增加,这两种脂质过氧化的标志物。LPS 处理的人 HK-2 细胞中检测到氧化脂质。在体内,肾皮质中出现了铁死亡特征性的超微结构变化,包括细胞体积缩小、核固缩和较小的线粒体。在体外,LPS 处理的人 HK-2 细胞中观察到线粒体膜电位的异常改变。铁死亡特异性抑制剂 ferrostatin-1 减轻了 LPS 诱导的肾脂质过氧化、铁死亡特征性的线粒体损伤和肾小管细胞死亡。机制上,LPS 刺激的 HK-2 细胞中线粒体来源的 ROS 增加。MitoQ,一种线粒体靶向抗氧化剂,几乎完全清除了人 HK-2 细胞中 LPS 刺激的线粒体 ROS。此外,MitoQ 预处理减轻了 LPS 诱导的小鼠肾脏 GSH 耗竭和脂质过氧化。最后,MitoQ 预处理减轻了 LPS 诱导的肾小管细胞死亡和 AKI。综上所述,这些结果表明,线粒体来源的 ROS 至少部分参与了 LPS 诱导的 AKI 期间肾小管细胞的铁死亡。线粒体靶向抗氧化剂可能是脓毒症诱导的 AKI 的潜在治疗药物。