Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan.
Nephrol Dial Transplant. 2020 Jan 1;35(1):74-85. doi: 10.1093/ndt/gfz073.
Renal tubulointerstitial lesions (TILs), a key pathological hallmark for chronic kidney disease to progress to end-stage renal disease, feature renal tubular atrophy, interstitial mononuclear leukocyte infiltration and fibrosis in the kidney. Our study tested the renoprotective and therapeutic effects of compound K (CK), as described in our US patent (US7932057B2), on renal TILs using a mouse unilateral ureteral obstruction (UUO) model.
Renal pathology was performed and renal draining lymph nodes were subjected to flow cytometry analysis. Mechanism-based experiments included the analysis of mitochondrial dysfunction, a model of tubular epithelial cells (TECs) under mechanically induced constant pressure (MICP) and tandem mass tags (TMT)-based proteomics analysis.
Administration of CK ameliorated renal TILs by reducing urine levels of proinflammatory cytokines, and preventing mononuclear leukocyte infiltration and fibrosis in the kidney. The beneficial effects clearly correlated with its inhibition of: (i) NF-κB-associated priming and the mitochondria-associated activating signals of the NLRP3 inflammasome; (ii) STAT3 signalling, which in part prevents NLRP3 inflammasome activation; and (iii) the TGF-β-dependent Smad2/Smad3 fibrotic pathway, in renal tissues, renal TECs under MICP and/or activated macrophages, the latter as a major inflammatory player contributing to renal TILs. Meanwhile, TMT-based proteomics analysis revealed downregulated renal NLRP3 inflammasome activation-associated signalling pathways in CK-treated UUO mice.
The present study, for the first time, presents the potent renoprotective and therapeutic effects of CK on renal TILs by targeting the NLRP3 inflammasome and STAT3 signalling.
肾小管间质病变（TILs）是慢性肾脏病进展为终末期肾病的关键病理标志，其特征为肾小管萎缩、间质单核白细胞浸润和肾脏纤维化。我们的研究使用单侧输尿管梗阻（UUO）模型测试了专利号为 US7932057B2 的美国专利中描述的化合物 K（CK）对肾 TILs 的保护和治疗作用。
进行肾脏病理学检查，并对肾脏引流淋巴结进行流式细胞术分析。基于机制的实验包括线粒体功能障碍分析、机械诱导恒压（MICP）下肾小管上皮细胞（TEC）模型和串联质量标签（TMT）-基于蛋白质组学分析。
CK 通过降低尿液中促炎细胞因子的水平，并防止单核白细胞浸润和肾脏纤维化，改善了肾 TILs。这些有益作用与 CK 抑制 NF-κB 相关的启动和 NLRP3 炎性体相关的线粒体激活信号、STAT3 信号（部分防止 NLRP3 炎性体激活）以及 TGF-β 依赖性 Smad2/Smad3 纤维化途径密切相关，这些途径在肾组织、MICP 下的肾 TEC 中和/或激活的巨噬细胞中均有作用，后者是导致肾 TILs 的主要炎症细胞。同时，TMT 蛋白质组学分析显示，CK 处理的 UUO 小鼠中肾脏 NLRP3 炎性体激活相关信号通路下调。
本研究首次提出 CK 通过靶向 NLRP3 炎性体和 STAT3 信号通路对肾 TILs 具有强大的保护和治疗作用。
