血红素加氧酶-1对TNF-α引起内皮细胞炎症损伤的保护作用

The cytoprotection of heme oxyenase-1 on the inflammatory reaction induced by tumor necrosis factor-α in endothelial cells

目的探讨血红素加氧酶-1(HO-1)在肿瘤坏死因子-α(TNF-α)导致肺微血管内皮细胞损伤中的保护作用。方法采用TNF-α刺激人肺微血管内皮细胞(HPMECs)模拟重症急性胰腺炎肺损伤的体外模型,锌原卟啉-IX(ZNPP-IX)作为HO-1抑制剂预处理细胞。试验分为对照组、TNF-α组、ZNPP-IX组。CCK8比色法检测细胞活性,采用Western blotting法及RT-PCR法检测HO-1、细胞间黏附分子-1(ICAM-1)的表达,黏附试验检测HPMECs对多形核细胞(PMN)的黏附力。结果 1与对照组相比,TNF-α组(78.69%±5.54%)、ZNPP-IX组(62.00%±4.27%)细胞活性明显降低(P<0.01);2与对照组相比,TNF-α组(1.59±0.19)HO-1表达增高(P<0.05),ZNPP-IX组(0.01±0.01)比TNF-α组显著降低(P<0.01);3与对照组相比,TNF-α组(32.72±0.95)、ZNPP-IX组(85.33±2.37)ICAM-1表达明显升高(P<0.01),且ZNPP-IX组比TNF-α组更显著(P<0.01);4TNF-α引起HPMECs对PMN黏附力增高,抑制HO-1表达后,黏附作用增强。结论 HO-1可能通过下调ICAM-1的表达降低炎症时HPMECs对PMN的黏附,从而改善重症急性胰腺炎引起的肺损伤。

Objective To investigate the cytoprotection of heme oxygenase-1（HO-1） on the inflammatory reaction induced by tumor necrosis factors（TNF-α） in human pulmonary microvascular endothelial cells（HPMECs）. Methods In this study, TNF-αwas used to mimic the acute lung injury（ALI） induced by severe acute pancreatitis（SAP） in vitro, ZNPP-IX was pretreatmented to inhibit the expression of HO-1. The experiment were divided into 3 groups, control group, TNF-α group and ZNPP-IX group. Cell viability was detected by CCK8, the expressions of HO-1 and ICAM-1 were analyzed with Western blotting and RT-PCR. The adhesion assay was used to measure the capacity of PMN adhere to HPMECs. Results 1 Compared with the control group, the cell viability of group TNF-αand ZNPP-IX were decreased significantly（P〈0.01）; 2The expression of HO-1 was increased in TNF-αgroup compared with the control group（P〈0.05）, but was decreased in ZNPPIX group（P〈0.01）; 3ICAM-1was increased both in group TNF-αand ZNPP-IX（P〈0.01）, and ZNPP-IX was more obviously（P〈0.01）; 4The adhesion of PMN to HPMECs was increased in TNF-αgroup, and it enhanced more after inhibiting HO-1 expression. Conclusion HO-1 down-regulates the expression of ICAM-1, which may alleviate PMN adhere to HPMECs, relieves the acute lung injury induced by SAP.