Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, 110004 Liaoning Province, China.
Mediators Inflamm. 2021 Jul 14;2021:5571272. doi: 10.1155/2021/5571272. eCollection 2021.
Paraquat (PQ) can cause multiorgan failure including acute kidney injury (AKI). Our prior study showed that Toll-interacting protein (TOLLIP) protected against PQ-induced acute lung injury. However, the role of TOLLIP in PQ-induced AKI remains undefined. This study was aimed at understanding the role and mechanism of TOLLIP in AKI. Six-eight-week-old male Wistar rats were intraperitoneally injected with 25 mg/kg PQ to induce AKI for 24 h . HK-2 cells were treated with 300 M PQ for 24 h to induce cellular injury or 300 M PQ and 5 M nuclear factor-B (NF-B) inhibitor BAY11-7082 for 24 h. Rats were infected with adenovirus carrying TOLLIP shRNA via tail vein injection and HK-2 cells with adenovirus carrying TOLLIP shRNA or TOLLIP 48 h before PQ exposure. Results showed that TOLLIP and Toll-like receptor 2/4 (TLR2/4) expressions were boosted in the kidney after PQ intoxication. The toxic effect of PQ on the kidney and HK-2 cells was exacerbated by TOLLIP knockdown, as evidenced by aggravated glomerulus and tubule injury, inflammatory infiltration, and cell apoptosis in the kidney and increased loss of cell viability and apoptotic cells in HK-2 cells. TOLLIP knockdown also enhanced PQ-induced NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation and and TLR2/4-NF-B signaling , reflected by increased contents of proinflammatory cytokines and expressions of NLRP3 inflammasome-related proteins in the kidney and HK-2 cells and expressions of TLR2, TLR4, and nuclear NF-B p65 in HK-2 cells. However, TOLLIP overexpression inhibited PQ-induced loss of cell viability, cell apoptosis, NLRP3 inflammasome activation, and TLR2/4-NF-B signaling . Additionally, BAY11-7082 abolished TOLLIP knockdown-induced NLRP3 inflammasome activation , indicating that TOLLIP protected against NLRP3 inflammasome activation in PQ-induced AKI through inhibiting TLR2/4-NF-B signaling. This study highlights the importance of TOLLIP in AKI after PQ intoxication.
百草枯（PQ）可导致多器官衰竭，包括急性肾损伤（AKI）。我们之前的研究表明，Toll 相互作用蛋白（TOLLIP）可防止 PQ 诱导的急性肺损伤。然而，TOLLIP 在 PQ 诱导的 AKI 中的作用仍未确定。本研究旨在了解 TOLLIP 在 AKI 中的作用和机制。将 6-8 周龄雄性 Wistar 大鼠腹腔注射 25mg/kg PQ 诱导 24h 的 AKI。将 HK-2 细胞用 300μM PQ 处理 24h 诱导细胞损伤，或用 300μM PQ 和 5μM 核因子-B（NF-B）抑制剂 BAY11-7082 处理 24h。通过尾静脉注射携带 TOLLIP shRNA 的腺病毒感染大鼠，并在 PQ 暴露前 48h 将携带 TOLLIP shRNA 或 TOLLIP 的腺病毒感染 HK-2 细胞。结果表明，PQ 中毒后肾脏中 TOLLIP 和 Toll 样受体 2/4（TLR2/4）的表达增加。TOLLIP 敲低加重了 PQ 对肾脏和 HK-2 细胞的毒性作用，表现为肾脏肾小球和肾小管损伤加重、炎症浸润和细胞凋亡增加以及 HK-2 细胞活力丧失和凋亡细胞增加。TOLLIP 敲低还增强了 PQ 诱导的 NLR 家族含 pyrin 结构域蛋白 3（NLRP3）炎性小体激活和 TLR2/4-NF-B 信号，表现为肾脏和 HK-2 细胞中促炎细胞因子含量和 NLRP3 炎性小体相关蛋白表达增加，以及 HK-2 细胞中 TLR2、TLR4 和核 NF-B p65 的表达增加。然而，TOLLIP 过表达抑制了 PQ 诱导的细胞活力丧失、细胞凋亡、NLRP3 炎性小体激活和 TLR2/4-NF-B 信号。此外，BAY11-7082 消除了 TOLLIP 敲低诱导的 NLRP3 炎性小体激活，表明 TOLLIP 通过抑制 TLR2/4-NF-B 信号抑制 PQ 诱导的 AKI 中的 NLRP3 炎性小体激活。本研究强调了 TOLLIP 在 PQ 中毒后 AKI 中的重要性。
