牛蒡子苷通过抑制内质网应激减轻晚期氧化蛋白产物诱导的HK-2细胞间充质转分化

摘要

目的：探讨牛蒡子苷对AOPPs诱导的肾小管上皮细胞EMT的影响及其机制。方法将体外培养的人肾小管上皮细胞（HK-2细胞）分为3组：牛血清白蛋白（BSA）组、AOPPs组、AOPPs+牛蒡子苷组，用Western blotting和实时荧光定量PCR分别检测细胞E-cadherin、vimentin和GRP78的蛋白和mRNA表达水平；以DCFH-DA为荧光探针，流式细胞术检测细胞内活性氧水平。结果与BSA组相比，AOPPs组的上皮细胞标志性蛋白E-cadherin的蛋白和mRNA表达水平下调、间充质细胞标志性蛋白vimentin和内质网应激标志性蛋白GRP78的蛋白和mRNA表达水平上调、细胞内活性氧水平升高；与AOPPs组相比，AOPPs+牛蒡子苷组E-cadherin蛋白和mRNA表达水平上调、vimentin和GRP78的蛋白和mRNA表达水平下调、细胞内活性氧水平降低。结论牛蒡子苷可能通过抑制内质网应激进而减轻AOPPs诱导的肾小管上皮细胞EMT的发生，且氧化应激参与该过程。%Objective To investigate the effect of arctiin on advanced oxidation protein product (AOPP)-induced epithelial-to-mesenchymal transition (EMT) in tubular cells and explore the mechanisms underlying this effect. Methods Human proximal tubular cells (HK-2 cells) were treated with bovine serum albumin (BSA) or AOPPs in the presence or absence of arctiin. The expressions of E-cadherin, vimentin, and GRP78 at the protein and mRNA levels in the cells were examined using Western blotting and quantitative real-time PCR. The level of reactive oxygen species (ROS) was measured by flow cytometry with DCFH-DA as the fluorescent probe. Results Compared with BSA-treated cells, the cells treated with AOPPs showed decreased expression of epithelial cell marker E-cadherin and overexpression of mesenchymal marker vimentin and endoplasmic reticulum stress marker GRP78 with an increased ROS level. These changes induced by AOPPs were partly inhibited by arctiin. Conclusion Arctiin can ameliorate AOPP-induced EMT in tubular cells by inhibiting endoplasmic reticulum stress, and oxidative stress response may participate in this process.