Heme oxygenase-1 protects rat liver against warm ischemia/reperfusion injury via TLR2/TLR4-triggered signaling pathways
Heme oxygenase-1 protects rat liver against warm ischemia/reperfusion injury via TLR2/TLR4-triggered signaling pathways
复制标题
血红素加氧酶-1通过TLR2/TLR4触发的信号通路保护大鼠肝脏免受热缺血/再灌注损伤
DOI：
10.3748/wjg.v21.i10.2937
复制
发表时间：
2015-03-14
影响因子：
4.3
通讯作者：
Duan, Jian
中科院分区：
文献类型：
--
作者：
Huang, Han-Fei;Zeng, Zhong;Duan, Jian
目的：为探讨诱导型血红素氧合酶（HO）-1对肝脏热缺血/再灌注（I/R）损伤的保护作用及其分子机制，采用SD大鼠肝左、中叶部分热缺血75 min，再灌注6 h的方法，观察HO-1对肝脏热缺血/再灌注损伤的保护作用。在缺血损伤前24 h用生理盐水、钴原卟啉（CoPP）或锌原卟啉（ZnPP）处理大鼠。再灌注6 h后收集血液和缺血叶标本。测定血清转氨酶、血浆乳酸脱氢酶和肝脏髓过氧化物酶活性。通过组织切片和肝脏免疫组化分析来评估肝脏组织学损伤和炎性细胞浸润。我们用定量逆转录聚合酶链反应分析肝脏炎症细胞因子和趋化因子的表达。细胞裂解物进行免疫沉淀与抗Toll-IL-1 R-含有衔接诱导干扰素-β（TRIF）和抗髓样分化因子88（MyD 88），然后通过SDS-PAGE和免疫印迹与指定的抗体进行分析。结果：HO-1保护肝脏I/R损伤，证明了减少肝酶和保存完好的组织结构。与术后6 h的ZnPP肝脏相比，CoPP治疗肝脏显示淋巴细胞、浆细胞、中性粒细胞和巨噬细胞的炎性细胞浸润显著增加。Toll样受体（TLR）-4和TANK结合激酶1的蛋白水平与CoPP治疗的大鼠显着降低TRIF-免疫沉淀复合物，与ZnPP治疗相比。CoPP预处理可降低MyD 88-免疫沉淀复合物中TLR 2、TLR 4、IL-1 R相关激酶（IRAK）-1和肿瘤坏死因子受体相关因子6的表达水平。与ZnPP处理组相比，CoPP预处理组肝脏中炎性细胞因子和趋化因子mRNA表达迅速下降。然而，与ZnPP处理的大鼠相比，CoPP处理的大鼠中含有负调节因子Toll相互作用蛋白、细胞因子信号传导抑制因子-1、IRAK-M和Src同源2结构域的肌醇-5-磷酸酶-1的表达明显上调。结论：HO-1通过抑制TLR 2/TLR 4介导的MyD 88-和TRIF-表达保护肝脏抗I/R损伤依赖的信号通路和增加表达TLR信号负调节。
AIM: To investigate the efficacy and molecular mechanisms of induced heme oxygenase (HO)-1 in protecting liver from warm ischemia/reperfusion (I/R) injury.METHODS: Partial warm ischemia was produced in the left and middle hepatic lobes of SD rats for 75 min, followed by 6 h of reperfusion. Rats were treated with saline, cobalt protoporphyrin (CoPP) or zinc protoporphyrin (ZnPP) at 24 h prior to the ischemia insult. Blood and samples of ischemic lobes subjected to ischemia were collected at 6 h after reperfusion. Serum transaminases level, plasma lactate dehydrogenase and myeloperoxidase activity in liver were measured. Liver histological injury and inflammatory cell infiltration were evaluated by tissue section and liver immunohistochemical analysis. We used quantitative reverse transcription polymerase chain reaction to analyze liver expression of inflammatory cytokines and chemokines. The cell lysates were subjected to immunoprecipitation with anti-Toll-IL-1R-containing adaptor inducing interferon-beta (TRIF) and anti-myeloid differentiation factor 88 (MyD88), and then the immunoprecipitates were analyzed by SDS-PAGE and immunoblotted with the indicated antibodies.RESULTS: HO-1 protected livers from I/R injury, as evidenced by diminished liver enzymes and well-preserved tissue architecture. In comparison with ZnPP livers 6 h after surgery, CoPP treatment livers showed a significant increase inflammatory cell infiltration of lymphocytes, plasma cells, neutrophils and macrophages. The Toll-like receptor (TLR)-4 and TANK binding kinase 1 protein levels of rats treated with CoPP significantly reduced in TRIF-immunoprecipitated complex, as compared with ZnPP treatment. In addition, pretreatment with CoPP reduced the expression levels of TLR2, TLR4, IL-1R-associated kinase (IRAK)-1 and tumor necrosis factor receptor-associated factor 6 in MyD88-immunoprecipitated complex. The inflammatory cytokines and chemokines mRNA expression rapidly decreased in CoPP-pretreated liver, compared with the ZnPP-treated group. However, the expression of negative regulators Toll-interacting protein, suppressor of cytokine signaling-1, IRAK-M and Src homology 2 domain-containing inositol-5-phosphatase-1 in CoPP treatment rats were markedly up-regulated as compared with ZnPP-treated rats.CONCLUSION: HO-1 protects liver against I/R injury by inhibiting TLR2/TLR4-triggered MyD88-and TRIF-dependent signaling pathways and increasing expression of negative regulators of TLR signaling in rats.