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 / 中国药理学通报

ABSTRACT

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 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.