外源性硫化氢抑制ox-LDL诱导血管内皮细胞组织因子的表达与降低ROS产生和抑制NF-κB活化有关

Exogenous hydrogen sulfide inhibits expression of tissue factor induced by ox-LDL through reducing generation of ROS and inhibiting NF-κB activation in endothelial cells

目的探讨外源性硫化氢抑制氧化型低密度脂蛋白(ox-LDL)诱导内皮细胞组织因子(TF)表达的机制。方法分别用不同浓度NaHS(25、50、100和200μmol·L-1)和50mg·L-1ox-LDL孵育人脐静脉内皮细胞(HUVECs),用RT-PCR和ELISA法检测HUVECs TF mRNA表达和蛋白含量,DCFH法测细胞内活性氧(ROS)的含量,Western blot测核蛋白转录因子(NF-κB)的活化。结果 ox-LDL明显诱导HUVECs TF mRNA的表达和蛋白含量增加;细胞内ROS水平升高,NF-κB活化。NaHS明显抑制了ox-LDL对TF mRNA和蛋白表达的诱导作用,同时降低ox-LDL诱导的细胞内ROS生成和NF-κB活化。此外,NF-κB抑制剂BAY 11-7082(10μmol·L-1)或抗氧化剂N-乙酰半胱氨酸(1 mmol·L-1)也能抑制ox-LDL诱导TF mRNA表达和蛋白含量的增加,同时降低细胞内ROS生成和NF-κB活化,该作用与200μmol·L-1NaHS的效应相似。结论 NaHS抑制ox-LDL诱导内皮细胞TF的表达与降低ROS产生和抑制NF-κB活化有关。

Aim To investigate the mechanism for the inhibitory effect of hydrogen sulfide on the expression of tissue factor（TF）induced by oxidative low-density lipoprotein（ox-LDL）in endothelial cells.Methods Human umbilical vein endothelial cells （HUVECs ） were treated with 50 mg·L-1 ox-LDL in the absence or presence of different concentrations of NaHS （25 , 50,100 and 200 μmol·L-1 ）for 24 h.The mRNA expression and protein content of TF in HUVECs were determined by reverse transcription PCR and ELISA, respectively.The content of intracellular reactive oxy-gen species （ROS）was determined by DCFH,an oxi-dative sensitive fluorescent indicator.The activation of nuclear factor-kappaB （NF-κB）was estimated by its expression in nuclear extracts analyzed by Western blot.Results Ox-LDL induced TF mRNA expression and increased TF protein content in HUVECs.The in-crease in intracellular ROS production and the activa-tion of NF-κB were observed in HUVECs treated with＆amp;nbsp;ox-LDL.However,NaHS could markedly inhibit the increases in TF mRNA and protein levels induced by ox-LDL.Also the elevation of intracellular ROS pro-duction and the activation of NF-κB elicited by ox-LDL were significantly suppressed by pretreatment with NaHS.In addition,pretreatment with BAY 1 1-7082 （10 μmol·L-1 ）,the inhibitor of NF-κB or N-acetyl-L-cysteine（1 mmol·L-1 ）,an antioxidant,could also decrease the TF mRNA and protein level as well as ROS production and NF-κB activation induced by ox-LDL in HUVECs,similar to the effects of 200 μmol· L-1 NaHS.Conclusion The mechanism for the in-hibitory effect of H2 S on the ox-LDL- induced TF ex-pression in endothelial cells may be related to inhibi-ting intracellular ROS production and subsequently NF-κB activation.