Department of Nephrology, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China.
Clin Sci (Lond). 2024 Mar 6;138(5):235-249. doi: 10.1042/CS20231184.
Contrast-induced nephropathy (CIN) is a leading cause of hospital-acquired acute kidney injury (AKI). Recently, ferroptosis was reported to be crucial for AKI pathogenesis. Our previous studies indicated antioxidant tetramethylpyrazine (TMP) prevent CIN in vivo. However, whether ferroptosis is involved in TMP nephroprotective mechanism against CIN is unclear. In the present study, we investigated the role of renal tubular epithelial cell ferroptosis in TMP reno-protective effect against CIN and the molecular mechanisms by which TMP regulates ferroptosis. Classical contrast-medium, Iohexol, was used to construct CIN models in rats and HK-2 cells. Results showed that tubular cell injury was accompanied by ferroptosis both in vivo and in vitro, including the typical features of ferroptosis, Fe2+ accumulation, lipid peroxidation and decreased glutathione peroxidase 4 (GPX4). Ferroptosis inhibition by classic inhibitors Fer-1 and DFO promoted cell viability and reduced intracellular ROS production. Additionally, TMP significantly inhibited renal dysfunction, reduced AKI biomarkers, prevented ROS production, inhibited renal Fe2+ accumulation and increased GPX4 expression. Expressions of various proteins associated with iron ion metabolism, including transferrin receptor (TFRC), divalent metal transporter 1, iron-responsive element binding protein 2, ferritin heavy chain 1, ferroportin 1, and heat shock factor binding protein 1, were examined using mechanistic analyses. Among these, TFRC changes were the most significant after TMP pretreatment. Results of siRNA knockdown and plasmid overexpression of TFRC indicated that TFRC is essential for TMP to alleviate ferroptosis and reduce LDH release, Fe2+ accumulation and intracellular ROS. Our findings provide crucial insights about the potential of TMP in treating AKI associated with ferroptosis.
对比剂诱导的肾病（CIN）是医院获得性急性肾损伤（AKI）的主要原因。最近，铁死亡被报道对 AKI 的发病机制至关重要。我们之前的研究表明，抗氧化剂川芎嗪（TMP）可预防体内 CIN。然而，铁死亡是否参与 TMP 对 CIN 的肾保护机制尚不清楚。在本研究中，我们研究了肾小管上皮细胞铁死亡在 TMP 预防 CIN 中的作用及其调节铁死亡的分子机制。经典的对比剂碘海醇被用于构建大鼠和 HK-2 细胞的 CIN 模型。结果表明，体内和体外肾小管细胞损伤均伴有铁死亡，包括铁死亡的典型特征，Fe2+积累、脂质过氧化和谷胱甘肽过氧化物酶 4（GPX4）减少。经典抑制剂 Fer-1 和 DFO 抑制铁死亡可促进细胞活力并减少细胞内 ROS 的产生。此外，TMP 可显著抑制肾功能障碍，降低 AKI 生物标志物，抑制 ROS 产生，抑制肾 Fe2+积累并增加 GPX4 表达。使用机制分析检查了与铁离子代谢相关的各种蛋白质的表达，包括转铁蛋白受体（TFRC）、二价金属转运蛋白 1、铁反应元件结合蛋白 2、铁蛋白重链 1、亚铁转运蛋白 1 和热休克因子结合蛋白 1。其中，TMP 预处理后 TFRC 的变化最为显著。TFRC 的 siRNA 敲低和质粒过表达结果表明，TFRC 是 TMP 缓解铁死亡和减少 LDH 释放、Fe2+积累和细胞内 ROS 所必需的。我们的研究结果为 TMP 治疗与铁死亡相关的 AKI 提供了重要的见解。
