1Department of Nephrology, Shanghai University of Medicine & Health Sciences affiliated Zhoupu Hospital, Pudong New District, Shanghai, 201318 China.
2Department of Geriatrics, Shanghai University of Medicine & Health Sciences affiliated Zhoupu Hospital, Pudong New District, Shanghai, 201318 China.
Cell Mol Biol Lett. 2019 May 22;24:32. doi: 10.1186/s11658-019-0157-x. eCollection 2019.
Peritoneal fibrosis remains a serious complication of long-term peritoneal dialysis (PD) leading to peritoneal membrane ultrafiltration failure. Epithelial-mesenchymal transition (EMT) of peritoneal mesothelial cells (PMCs) is a key process of peritoneal fibrosis. Curcumin has been previously shown to inhibit EMT of renal tubular epithelial cells and prevent renal fibrosis. There are only limited reports on inhibition of PMCs-EMT by curcumin. This study aimed to investigate the effect of curcumin on the regulation of EMT and related pathway in PMCs treated with glucose-based PD.
EMT of human peritoneal mesothelial cells (HMrSV5) was induced with glucose-based peritoneal dialysis solutions (PDS). Cells were divided into a control group, PDS group, and PDS group receiving varied concentrations of curcumin. Cell Counting Kit-8 (CCK-8) assay was used to measure cell viability, and a transwell migration assay was used to verify the capacity of curcumin to inhibit EMT in HMrSV5 cells. Real-time quantitative PCR and western blot were used to detect the expression of genes and proteins associated with the EMT.
High glucose PDS decreased cell viability and increased migratory capacity. Curcumin reversed growth inhibition and migration capability of human peritoneal mesothelial cells (HPMCs). In HMrSV5 cells, high glucose PDS also decreased expression of epithelial markers, and increased expression of mesenchymal markers, a characteristic of EMT. Real-time RT-PCR and western blot revealed that, compared to the 4.25% Dianeal treated cells, curcumin treatment resulted in increased expression of E-cadherin (epithelial marker), and decreased expression of α-SMA (mesenchymal markers) ( < 0.05). Furthermore, curcumin reduced mRNA expression of two extracellular matrix protein, collagen I and fibronectin. Curcumin also reduced TGF-β1 mRNA and supernatant TGF-β1 protein content in the PDS-treated HMrSV5 cells ( < 0.05). Furthermore, it significantly reduced protein expression of p-TAK1, p-JNK and p-p38 in PDS-treated HMrSV5 cells.
Our results demonstrate that curcumin showed an obvious protective effect on PDS-induced EMT of HMrSV5 cells and suggest implication of the TAK1, p38 and JNK pathway in mediating the effects of curcumin in EMT of MCs.
腹膜纤维化仍然是长期腹膜透析（PD）导致腹膜超滤失败的严重并发症。上皮-间充质转化（EMT）是腹膜间皮细胞（PMCs）发生腹膜纤维化的关键过程。姜黄素已被证明能抑制肾小管上皮细胞的 EMT，并预防肾纤维化。只有有限的报告表明姜黄素能抑制 PMCs-EMT。本研究旨在探讨姜黄素对葡萄糖基 PD 处理的 PMCs 的 EMT 及相关途径的调节作用。
用葡萄糖基腹膜透析液（PDS）诱导人腹膜间皮细胞（HMrSV5）的 EMT。细胞分为对照组、PDS 组和 PDS 组，PDS 组分别接受不同浓度的姜黄素。细胞计数试剂盒-8（CCK-8）法用于测量细胞活力，Transwell 迁移实验用于验证姜黄素抑制 HMrSV5 细胞 EMT 的能力。实时定量 PCR 和 Western blot 用于检测与 EMT 相关的基因和蛋白的表达。
高糖 PDS 降低细胞活力，增加迁移能力。姜黄素逆转了人腹膜间皮细胞（HPMCs）的生长抑制和迁移能力。在 HMrSV5 细胞中，高糖 PDS 还降低了上皮标志物的表达，增加了间充质标志物的表达，这是 EMT 的特征。实时 RT-PCR 和 Western blot 显示，与 4.25% Dianeal 处理的细胞相比，姜黄素处理导致 E-钙粘蛋白（上皮标志物）的表达增加，α-SMA（间充质标志物）的表达减少（ < 0.05）。此外，姜黄素降低了细胞外基质蛋白胶原 I 和纤连蛋白的 mRNA 表达。姜黄素还降低了 PDS 处理的 HMrSV5 细胞上清液中 TGF-β1mRNA 和 TGF-β1 蛋白含量（ < 0.05）。此外，它还显著降低了 PDS 处理的 HMrSV5 细胞中 p-TAK1、p-JNK 和 p-p38 的蛋白表达。
我们的结果表明，姜黄素对 HMrSV5 细胞 PDS 诱导的 EMT 有明显的保护作用，并提示 TAK1、p38 和 JNK 途径在介导姜黄素对 MCs EMT 的作用。
