Alteration Of Plasma Vascular Peroxidase Levels In Patients With Coronary Artery Diseases And Its Involvement In Vascular Inflammatory Reaction

Objective:we investigated the alteration of plasma vascular peroxidase(VPO)levels in patients coronary artery diseases,and the effect of VPO on oxidized low-denisity lipoprotein(ox-LDL)vascular inflammatory reaction in endothelial cells.Method:The study included clinical and experimental serials.In clinical study,139 patients with coronary artery diseases(CAD) including 72 acute coronery syndrome(ACS)and 67 stable angina pectoris(SAP),47 healthy subjects were recruited.The enzyme linked-immuno sorbent assay(ELISA)method was used for plasma concentration of tumor necrosis factor-α(TNF-α)and activity of myeloperoxidase(MPO)measurement,while the plasma protein levels of VPO and MPO were detected using Western blotting.In vitro study, endothelial cells were cultured,the expression of VPO in endothelial cell was detected using Western Blotting,intracellular reactive oxygen species(ROS)levels was measured by fluorometric method,and the TNF-αlevels in cultured of endothelial cell was determined by ELISA.Results:1.The plasma levels of TNF-αand VPO were significantly higher in the CAD patients than in the control(P＜0.01 and P＜0.01,respectively).Moreover it was significantly higher in ACS than that in SAP(P＜0.01).The plasma MPO levels in ACS was significantly higher than that in SAP or in control group (P＜0.01).However,there was only a tendency toward increase in MPO level in SAP group when comparing with control group(P＞0.05).2.Ox-LDL increased the TNF-αlevels in.endothelial cell supernatant fluid in a time- or -concentration-dependent manner. ox-LDL at the concentration of 100 mg/L promoted the expression of VPO in endothelial cell and increased the intracellular ROS levels in a time-dependent manner.3.Ox-LDL(100 mg/L,24 h)promoted the expression of VPO in endothelial cell and increased the intracellular ROS levels.The endothelial cells were incubated in pyrollidine dithiocarbamate (PDTC(100μM))for 1 h and followed by incubation with ox-LDL(100 mg/L)for 24 h.After that,either the increased VPO expression or ROS level by ox-LDL was significantly inhibited.Conclusion:1.Plasma VPO levels significantly increases in patients with coronary artery diseases.2.Ox-LDL may induce VPO expression in endothelial cells.3.Ox-LDL promotes the secretion of TNF-αin endothelial cells.This property may play a role in the induction of VPO expression in endothelial cells and increase in the intracellular ROS levels.