摘　要：为探索高尿酸环境诱导下的大鼠肾细胞（NRK-52E）中锌α2糖蛋白（ZAG）与细胞外信号调节激酶1/2（ERK1/2）和p38形成反馈通路调控肾细胞上皮间质转化（EMT）的机制，将NRK-52E分为正常培养组（N组）和高尿酸培养组（H组）（20 mg/dL的尿酸刺激48 h），每组中的细胞都分别进行ZAG的过表达转染和敲低，观察细胞中ZAG的表达水平与ERK1/2和p38信号通路的交互作用。结果发现：相较于N组，高尿酸环境下的NRK-52E中EMT相关分子的mRNA及蛋白质的表达均上调（P<0.05）；在高尿酸环境培养下，上调ZAG会减少NRK-52E在该通路中丝裂原活化蛋白激酶激酶（MAPKK）、ERK1/2、p38、活化转录因子2（ATF2）及蛋白激酶B（PKB或Akt）mRNA的表达量（P<0.01），而ZAG的下调则会增加（P<0.05）。在蛋白层面上，相较于未转染组，ZAG上调组的MAPKK、p38和Akt的表达量减少（P<0.05、P<0.01、P<0.001）；ZAG下调组的ERK1/2、p38和Akt的表达量增加（P<0.001、P<0.05、P<0.01）。结果表明：ZAG的转染上调会减少NRK-52E中与EMT相关的标志物波形蛋白（vimentin）和层黏连蛋白（laminin）mRNA的表达量；调控ZAG在NRK-52E中的表达量可以在ERK1/2和p38信号通路中起到积极作用，进而抑制肾细胞EMT。该研究为临床治疗高尿酸血症肾病（HN）提供了试验依据。

关键词：肾纤维化；上皮细胞间充质转化；尿酸性肾病；高尿酸；锌α2糖蛋白

中图分类号：R361                                 文献标志码：ADOI：10.3969/j.issn.1007-7146.2024.02.010

（School of Basic Medical Sciences, Youjiang Medical University for Nationalities, Baise 533000, China）

Abstract: The aim of this paper is to explore the mechanism of zinc-α2-glycoprotein (ZAG) forming a feedback pathway with extracellular signal- regulated kinase 1/2 (ERK1/2) and p38 to regulate epithelial mesenchymal transition (EMT) in rat renal epithelial cells (NRK-52E) induced by high uric acid environment, we divided NRK-52E into normal control group and high uric acid-induced group which was stimulated by 20 mg/dL uric acid for 48 h, and the cells in each group were transfected with overexpression of ZAG and knocked down respectively, to observe the interactions between ZAG expression level and ERK1/2 and p38 signaling pathways in the cells. The results revealed that the mRNA and protein expression of EMT-related molecules were elevated in rat kidney cells under high uric acid environment compared with the normal culture group (P<0.05); up-regulation of ZAG decreased the expression of mitogen-activated protein kinase kinase (MAPKK), ERK1/2, p38, activated transcription factor-2 (ATF2) and protein kinase B (PKB or Akt) mRNA in this pathway in rat kidney epithelial cells under high uric acid environment culture (P<0.01), while the downregulation of ZAG increased (P<0.05). At the protein level, the expression of MAPKK, p38 and Akt decreased in the ZAG up-regulated group compared to the untransfected group (P<0.05, P<0.01, P<0.001); and the expression of ERK1/2, p38 and Akt was elevated in the ZAG down-regulated group (P<0.001, P<0.05, P<0.01). The results suggest that transfection up-regulation of ZAG decreases the expression of laminin and vimentin mRNA, the marker genes related to EMT in NRK-52E; regulation of ZAG expression in NRK-52E can play a positive role in ERK1/2 and p38 signaling pathways, and thus inhibit renal cell EMT. This study provides an experimental basis for clinical treatment of hyperuricemic nephropathy (HN).

Key words: nephrofibrotic: epithelial mesenchymal transformation of urine; uric acid nephropathy; hyperuricemia; zinc-α2-glycoprotein

（Acta Laser Biology Sinica, 2024, 33(2): 176-184）