Cai Fangfang, Li Dangran, Zhou Kaiqian, Zhang Wen, Yang Yunwen
School of Biopharmacy, China Pharmaceutical University, Nanjing 211198, China.
The State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China.
Phytomedicine. 2024 Apr;126:155407. doi: 10.1016/j.phymed.2024.155407. Epub 2024 Feb 2.
Ferroptosis, an iron-dependent process that regulates cell death. Emerging evidences suggest that ferroptosis induces acute kidney injury (AKI) progression, and inhibiting ferroptosis provides an effect strategy for AKI treatment. The disruption of the NRF2-KEAP1 protein to protein interaction (PPI) induces NRF2 activation, which provides a promising strategy that can identify new ferroptosis inhibitors. A previous study revealed that tiliroside, a glycosidic flavonoid extracted from Edgeworthia chrysantha Lindl (buds), has anti-neuroinflammatory and neuroprotective effects via NRF2 activation. However, the mechanism through which tiliroside activates NRF2 is unknown, and it remains unclear whether it has protective effects against AKI.
To investigate whether tiliroside has protective effects against AKI in mice and the associated mechanisms.
Possible tiliroside substrates were analyzed using molecular docking. Cisplatin- and ischemia-reperfusion injury (IRI)-induced AKI mouse models and HK2 cells model were constructed to evaluate the protective effects of tiliroside. CRISPR/Cas9 mediated NRF2 knockout HK2 cells were used to verify whether NRF2 mediates tiliroside protective effects.
In vivo, our results showed that tiliroside treatment preserved kidney functions in AKI mice models, as showed by lower levels of serum creatinine (SCr), blood urea nitrogen (BUN), and renal injury markers, including neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (KIM1), compared with the mice in control groups. In vitro, tiliroside treatment greatly ameliorated cisplatin-induced ferroptosis through NRF2 activation in cultured HK2 cells, as evidenced by the protective effects of tiliroside being greatly blunted after the knockout of NRF2 in HK2 cells. Mechanistic studies indicated that tiliroside promoted NRF2/GPX4 pathway activation and ferroptosis inhibition, perhaps via the disruption of the NRF2-KEAP1 PPI.
Together, our results demonstrate that tiliroside may serve as a NRF2-KEAP1 PPI inhibitor and prevents ferroptosis-induced AKI, indicating its potential for clinical AKI treatment.
铁死亡是一种调节细胞死亡的铁依赖性过程。新出现的证据表明，铁死亡会促使急性肾损伤（AKI）进展，而抑制铁死亡为AKI治疗提供了一种有效的策略。NRF2-KEAP1蛋白与蛋白相互作用（PPI）的破坏会诱导NRF2激活，这为识别新的铁死亡抑制剂提供了一种有前景的策略。先前的一项研究表明，椴树苷是从结香（花蕾）中提取的一种糖苷类黄酮，通过激活NRF2具有抗神经炎症和神经保护作用。然而，椴树苷激活NRF2的机制尚不清楚，其对AKI是否具有保护作用也仍不明确。
研究椴树苷对小鼠AKI是否具有保护作用及其相关机制。
使用分子对接分析可能的椴树苷底物。构建顺铂和缺血再灌注损伤（IRI）诱导的AKI小鼠模型以及HK2细胞模型，以评估椴树苷的保护作用。使用CRISPR/Cas9介导的NRF2基因敲除HK2细胞来验证NRF2是否介导椴树苷的保护作用。
在体内，我们的结果表明，与对照组小鼠相比，椴树苷治疗可维持AKI小鼠模型的肾功能，血清肌酐（SCr）、血尿素氮（BUN）以及肾损伤标志物（包括中性粒细胞明胶酶相关脂质运载蛋白（NGAL）和肾损伤分子1（KIM1））水平较低。在体外，椴树苷治疗通过在培养的HK2细胞中激活NRF2，极大地改善了顺铂诱导的铁死亡，HK2细胞中NRF2基因敲除后，椴树苷的保护作用大大减弱，这证明了这一点。机制研究表明，椴树苷可能通过破坏NRF2-KEAP1 PPI促进NRF2/GPX4途径激活并抑制铁死亡。
总之，我们的结果表明，椴树苷可能作为一种NRF2-KEAP1 PPI抑制剂，预防铁死亡诱导的AKI，表明其在临床AKI治疗中的潜力。
