Li Lei, Ye Zehua, Xia Yuqi, Li Bojun, Chen Lijia, Yan Xinzhou, Yuan Tianhui, Song Baofeng, Yu Weimin, Rao Ting, Lin Fangyou, Zhou Xiangjun, Cheng Fan
Department of Urology, Renmin Hospital of Wuhan University, Wuhan 430060, China.
Biomedicines. 2023 Oct 1;11(10):2692. doi: 10.3390/biomedicines11102692.
The potential association between calcium oxalate stones and renal fibrosis has been extensively investigated; however, the underlying mechanisms remain unclear. Ferroptosis is a novel form of cell death characterized by iron-dependent lipid peroxidation and regulated by acyl coenzyme A synthase long-chain family member 4 (ACSL4). Yes-associated protein (YAP), a transcriptional co-activator in the Hippo pathway, promotes ferroptosis by modulating ACSL4 expression. Nevertheless, the involvement of YAP-ACSL4 axis-mediated ferroptosis in calcium oxalate crystal deposition-induced renal fibrosis and its molecular mechanisms have not been elucidated. In this study, we investigated ACSL4 expression and ferroptosis activation in the kidney tissues of patients with calcium oxalate stones and in mice using single-cell sequencing, transcriptome RNA sequencing, immunohistochemical analysis, and Western blot analysis. In vivo and in vitro experiments demonstrated that inhibiting ferroptosis or ACSL4 mitigated calcium oxalate crystal-induced renal fibrosis. Furthermore, YAP expression was elevated in the kidney tissues of patients with calcium oxalate stones and in calcium oxalate crystal-stimulated human renal tubular epithelial cell lines. Mechanistically, in calcium oxalate crystal-stimulated human renal tubular epithelial cell lines, activated YAP translocated to the nucleus and enhanced ACSL4 expression, consequently inducing cellular ferroptosis. Moreover, YAP silencing suppressed ferroptosis by downregulating ACSL4 expression, thereby attenuating calcium oxalate crystal-induced renal fibrosis. Conclusively, our findings suggest that YAP-ACSL4-mediated ferroptosis represents an important mechanism underlying the induction of renal fibrosis by calcium oxalate crystal deposition. Targeting the YAP-ACSL4 axis and ferroptosis may therefore hold promise as a potential therapeutic approach for preventing renal fibrosis in patients with kidney stones.
草酸钙结石与肾纤维化之间的潜在关联已得到广泛研究；然而，其潜在机制仍不清楚。铁死亡是一种新型细胞死亡形式，其特征是铁依赖性脂质过氧化，并受酰基辅酶A合成酶长链家族成员4（ACSL4）调控。Yes相关蛋白（YAP）是H）是Hippo通路中的一种转录共激活因子，通过调节ACSL4表达促进铁死亡。然而，YAP-ACSL4轴介导的铁死亡在草酸钙晶体沉积诱导的肾纤维化中的作用及其分子机制尚未阐明。在本研究中，我们使用单细胞测序、转录组RNA测序、免疫组织化学分析和蛋白质印迹分析，研究了草酸钙结石患者和小鼠肾组织中ACSL4的表达和铁死亡激活情况。体内和体外实验表明，抑制铁死亡或ACSL4可减轻草酸钙晶体诱导的肾纤维化。此外，草酸钙结石患者的肾组织和草酸钙晶体刺激的人肾小管上皮细胞系中YAP表达升高。机制上，在草酸钙晶体刺激的人肾小管上皮细胞系中，活化的YAP易位至细胞核并增强ACSL4表达，从而诱导细胞铁死亡。此外，YAP沉默通过下调ACSL4表达抑制铁死亡，从而减轻草酸钙晶体诱导的肾纤维化。总之，我们的研究结果表明，YAP-ACSL4介导的铁死亡是草酸钙晶体沉积诱导肾纤维化的重要机制。因此，靶向YAP-ACSL4轴和铁死亡可能有望成为预防肾结石患者肾纤维化的潜在治疗方法。
