Bay11-7082通过抑制足细胞焦亡减轻膜性肾病组织损伤

Bay11-7082 alleviated renal injury in membranous nephropathy by inhibiting podocyte pyroptosis

目的:探索细胞焦亡抑制剂Bay11-7082对膜性肾病(MN)的保护效应及机制。方法:建立C3a/C5a足细胞损伤模型并予Bay11-7082干预,观察细胞损伤及焦亡信号通路的变化情况;建立被动Heymann肾炎(PHN)大鼠模型并予Bay11-7082干预,检测24 h尿蛋白定量、血清白蛋白,评估肾组织病理损伤并观察肾组织和足细胞焦亡信号通路的变化情况。结果:Bay11-7082通过抑制焦亡减轻C3a/C5a介导的足细胞损伤,表现为碘化吡啶(PI)染色阳性细胞数及乳酸脱氢酶释放减少,NF-κB-NLRP3-ASC-Caspase-1-IL-18/GSDMD焦亡信号通路下调;Bay11-7082通过抑制焦亡减轻PHN大鼠肾组织和足细胞损伤,表现为模型鼠24 h尿蛋白下降、血清白蛋白升高,肾小球结蛋白表达下降、足细胞核Wilms瘤基因1表达上升、足细胞足突融合减轻,NF-κB-NLRP3-ASC-Caspase-1-IL-1β/IL-18/GSDMD焦亡信号通路下调。结论:Bay11-7082通过抑制足细胞焦亡在MN肾组织损伤中发挥保护作用。

Objective:To investigate effect and underlying mechanisms of a pyroptosis inhibitor, Bay11-7082, in treatment of membranous nephropathy(MN). Methodology:Bay11-7082 was administered to a C3 a/C5 a-induced podocyte injury model in vitro. Cell injury was evaluated according to propidium iodide(PI) staining and lactate dehydrogenase(LDH) release. Alterations in pyroptosis signaling pathways were observed through immunofluorescence, Western-blot and ELISA. Passive Heymann nephritis(PHN) rat model was established and treated with Bay11-7082. Renal and podocyte injuries were evaluated through 24 h urine protein(24 h-UPro), serum albumin(ALB), renal histopathology, immunohistochemical staining of Desmin/WT-1. Changes in pyroptosis signaling pathways were observed through immunofluorescence, immunohistochemistry, RT-qPCR, Western-blot and ELISA. Results:Bay11-7082 ameliorated C3 a/C5 a-induced podocyte injury by inhibiting pyroptosis, as demonstrated by decreased percentage of PI-positive cells and LDH release along with downregulation of NF-κB-NLRP3-ASC-Caspase-1-IL-18/GSDMD pyroptosis signaling pathway. Bay11-7082 alleviated renal and podocyte injuries in PHN rats by inhibiting pyroptosis, as reflected by improvement of renal injury, including decreased 24 h-UPro and Desmin expression in podocyte, increased ALB and WT-1 expression in podocyte nuclei, and significantly alleviated podocyte foot process fusion under transmission electron microscopy. The NF-κB-NLRP3-ASC-Caspase-1-IL-1β/IL-18/GSDMD pyroptosis signaling pathway was also downregulated in the glomeruli. Conclusion:Bay11-7082 alleviated renal lesions in MN by inhibiting complement-induced podocyte pyroptosis.