摘要目的:探讨X盒结合蛋白1（XBP1）调控硫氧还蛋白互作蛋白-NOD样受体3（TXNIP-NLRP3）通路对小鼠肾小管上皮细胞（TCMK-1）缺氧复氧（H/R）模型的影响及其作用机制。方法:根据干预的不同将细胞分为4组：si-NC组：转染小干扰RNA（siRNA）阴性对照（si-NC）；si-XBP1组：转染靶向沉默XBP1的siRNA（si-XBP1）；si-NC+H/R组：转染si-NC后H/R处理；si-XBP1+H/R组：转染si-XBP1后H/R处理。磷脂结合蛋白Ⅴ/碘化丙啶双标染色法检测细胞凋亡，JC-1探针染色法检测线粒体膜电位（MMP），MitoSOX?探针染色法检测线粒体活性氧（mROS），Western印迹和实时定量PCR检测XBP1的蛋白质和mRNA水平以验证干扰效率，Western印迹检测TXNIP、NLRP3和白细胞介素-1β（IL-1β）的蛋白质水平变化，免疫荧光法检测线粒体和TXNIP共定位变化。使用独立样本 t检验比较组间差异。 结果:与si-NC组相比，si-NC+H/R组细胞凋亡率较高，mROS产生较多，MMP较低；与si-NC+H/R组相比，si-XBP1+H/R组细胞凋亡率较低（12.08±0.51比19.01±1.80， P<0.05），mROS产生较少（34.63±0.64比48.17±1.84， P<0.01），MMP较高（1.03±0.11比0.45±0.08， P<0.05）；在H/R时干扰XBP1U（蛋白质：1.31±0.18比0.23±0.02， P<0.01；mRNA：1.12±0.07比0.38±0.01， P<0.001）和XBP1S（蛋白质：1.13±0.17比0.28±0.07， P<0.01；mRNA：8.39±0.63比2.45±0.22， P<0.001）表达后，TXNIP（0.15±0.02比0.04±0.01， P<0.01）、NLRP3（1.13±0.12比0.51±0.12， P<0.05）、IL-1β（1.02±0.04比0.19±0.06， P<0.001）蛋白质的表达更低，同时，线粒体和TXNIP的共定位水平也更低。 结论:抑制XBP1表达能够减轻TCMK-1的H/R损伤，其机制可能是通过抑制TXNIP介导的NLRP3炎症小体的活化。

abstractsObjective:To investigate the role and regulation mechanism of X box binding protein 1 (XBP1) for hypoxia/reoxygenation(H/R) injury in mouse renal tubular epithelial cells (TCMK-1) through thioredoxin interacting protein (TXNIP)-nucleotide-binding domain (NOD)-like receptor protein (TXNIP-NLRP3) signaling pathway.Methods:The cells were divided into 4 groups: si-NC group transfected with negative control siRNA (si-NC), si-XBP1 group transfected with siRNA targeting XBP1 (si-XBP1), si-NC+H/R group transfected with si-NC and exposed to H/R, and si-XBP1+H/R group transfected with si-XBP1 and exposed to H/R. The Annexin Ⅴ/PI double-staining method was used to detect cell apoptosis; The mitochondrial membrane potential (MMP) was determined by using JC-1 dye; The mitochondrial reactive oxygen species (mROS) was assessed by using MitoSOX? dye. The interference efficiency of XBP1 was tested by Western blotting and quantitative real-time polymerase chain reaction. The expression levels of TXNIP, NLRP3 and IL-1β protein were detected by Western blotting. The colocalization of mitochondria and TXNIP was detected by double-labeling immunofluorescent staining. The intergroup difference was compared by using an independent samples t-test. Results:Compared with the si-NC group, more mROS, apoptosis and lower MMP were observed in si-NC+H/R group. Compared with the si-NC+H/R group, less apoptosis (12.08±0.51 vs 19.01±1.80, P<0.05), mROS (34.63±0.64 vs 48.17±1.84, P<0.01) and higher MMP (1.03±0.11 vs 0.45±0.08, P<0.05) were observed in si-XBP1+H/R group. Down-regulation of XBP1U (protein: 1.31±0.18 vs 0.23±0.02, P<0.01; mRNA: 1.12±0.07 vs 0.38±0.01, P<0.001) and XBP1S (protein: 1.13±0.17 vs 0.28±0.07, P<0.01; mRNA: 8.39±0.63 vs 2.45±0.22, P<0.001) inhibited expression of TXNIP (0.15±0.02 vs 0.04±0.01, P<0.01), NLRP3 (1.13±0.12 vs 0.51±0.12, P<0.05) and IL-1β (1.02±0.04 vs 0.19±0.06, P<0.001) during H/R. Meanwhile, TXNIP exhibited significantly much less colocalization with mitochondria in the si-XBP1+H/R group. Conclusion:Supression of XBP1 expression can effectively alleviate H/R-induced TCMK-1 cells injury, whose mechanism may be inhibition of TXNIP-induced NLRP3 inflammasome activation.