Department of Pharmacy, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230001, China; Office of Drug Clinical Trial Institutions, Anhui Provincial Cancer Hospital, Hefei 230031, China.
Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei 230032, China.
Int Immunopharmacol. 2024 Dec 25;143(Pt 1):113226. doi: 10.1016/j.intimp.2024.113226. Epub 2024 Sep 30.
Liver fibrosis is a sustained process of liver tissue damage and repair caused by various physiological and pathological factors, with the activation and proliferation of hepatic stellate cells being central. Therefore, understanding and clarifying the relevant mechanisms of hepatic stellate cell activation and death is of great clinical significance for the treatment of liver fibrosis diseases.
In vivo, recombinant adeno-associated virus was used to infect the liver of experimental mice, overexpressing ASIC1a, and based on this, a liver fibrosis model treated with sorafenib was constructed. In vitro, using RNA plasmid technology to transfect HSC-T6 cells, ASIC1a was overexpressed or silenced in the cells, and on this basis, PDGF-BB and Sorafenib were used to stimulate HSC-T6 cells, causing activated HSC-T6 to undergo ferroptosis.
The ferroptosis inducers Sorafenib and erastin can induce ferroptosis in HSCs, effectively inhibiting or reversing the progression of liver fibrosis. We found that the expression level of ASIC1a was significantly reduced in the livers of mice with liver fibrosis treated with Sorafenib. After treatment with an adeno-associated virus overexpressing ASIC1a, the therapeutic effect of Sorafenib was inhibited, and the level of ferroptosis induced by Sorafenib was also inhibited. The induction of ferroptosis in hepatic stellate cells in vitro depends on the presence of ASIC1a. By further exploring the potential mechanism, we observed that the overexpression of ASIC1a can promote an increase in YAP nuclear translocation, thereby regulating the activity of Hippo/YAP pathway signaling. After treatment with Sorafenib, the influx of Ca significantly increased when ASIC1a was overexpressed, and BAPTA-AM intervention eliminated the intracellular Ca accumulation induced by ASIC1a overexpression.
This indicated that the activation of YAP depends on the calcium ion influx induced by ASIC1a, which regulates ferroptosis in hepatic stellate cells by regulating the calcium ion-dependent Hippo/YAP pathway.
肝纤维化是由各种生理和病理因素引起的肝组织损伤和修复的持续过程，其中肝星状细胞的激活和增殖是核心。因此，了解和阐明肝星状细胞激活和死亡的相关机制，对于肝纤维化疾病的治疗具有重要的临床意义。
在体内，使用重组腺相关病毒感染实验小鼠的肝脏，过表达 ASIC1a，并在此基础上构建了索拉非尼治疗的肝纤维化模型。在体外，采用 RNA 质粒技术转染 HSC-T6 细胞，过表达或沉默 ASIC1a，在此基础上用 PDGF-BB 和索拉非尼刺激 HSC-T6 细胞，使激活的 HSC-T6 发生铁死亡。
铁死亡诱导剂索拉非尼和 erastin 可诱导 HSCs 发生铁死亡，有效抑制或逆转肝纤维化的进展。我们发现，索拉非尼治疗的肝纤维化小鼠肝脏中 ASIC1a 的表达水平显著降低。用过表达 ASIC1a 的腺相关病毒处理后，索拉非尼的治疗效果受到抑制，索拉非尼诱导的铁死亡水平也受到抑制。体外诱导肝星状细胞铁死亡依赖于 ASIC1a 的存在。通过进一步探讨潜在机制，我们观察到 ASIC1a 的过表达可促进 YAP 核易位增加，从而调节 Hippo/YAP 通路信号的活性。过表达 ASIC1a 后，用索拉非尼处理时，Ca 内流显著增加，BAPTA-AM 干预消除了 ASIC1a 过表达诱导的细胞内 Ca 积累。
这表明 YAP 的激活依赖于 ASIC1a 诱导的钙离子内流，通过调节钙依赖性 Hippo/YAP 通路来调节肝星状细胞的铁死亡。
