Correlation Between The Myeloperoxidase Genetic Polymorphism And Coronary Artery Disease

【Objective】Myeloperoxidase(MPO), a leukocyte enzyme that promotes oxidation of lipoproteins in atheroma, has been proposed as a possible mediator of atherosclerosis. There is a functional polymorphism 463 by upstream of the enzyme. A lot of results have been reported overseas that MPO polymorphism has a significant correlation with coronary heart disease(CHD), but there is few civil relative research. In this study, the importance of MPO polymorphism was further evaluated in Chinese.【Methods】A case-control study was performed in 219 CHD patients and 70 controls proved by angiography. CHD patients were including 74 patients with stable angina pectoris(SAP), 97 patients with unstable angina pectoris(UAP), 48 with acute myocardial infarction(AMI). The plasma level of MPO was detected by ELISA and compared between the groups. PCR-RFLP methods and gene-Sequencing Analyses were used to decide the genotype of the patients. And at the same time, we measured the plasma levels of TC,TG,LDL-C,HDL-C and so on in Yangzhou No.1 people's Hospital.【Results】1 The plasma levels of MPO were obviously higher in ACS groups than that in SAP and control group(P<0.01), The mean levels of plasma MPO in SAP group were not significant difference, compared with that in control group(P>0.05).2 The plasma levels of MPO among single, double and three vessel lesion group were higher than that in control group(P<0.05), The plasma levels of MPO among 1-20, 21-40 and >40 group were higher than that in control group(P<0.05). 3 There was positive correlation between the level of plasma MPO and the number of WBC(P<0.05), but there was no obvious correlation between the level of plasma MPO and age, gender, smoking, hypertension, diabetes and the level of TC,TG,LDL-C(P>0.05).4 The frequency distribution of the genotype and allele alleles differ significantly between patients groups and controls(X2=7.711, P<0.05); the risk of CHD in the GA genotype was 3.10 times higher than that of AA. The risk of CHD in the GG genotype was 2.70 times higher than that of AA.5 The distribution of A/A,G/A and G/G were difference among single, double and three vessel lesion group(P<0.05), as well as the allele frequencies of G and A (P<0.05); the distribution of A/A,G/A and G/G were difference among 1-20, 21-40 and >40 group (P<0.05), as well as the allele frequencies of G and A(P<0.05).【Conclusions】Plasma MPO content was related to the clinical severity of CHD, but also to the degree of coronary artery lesions. This suggested that the increased level of MPO may be connected with plaque vulnerability and the onset of ACS, and MPO could serve as an inflammatory marker for ACS. The frequency of genotype and alleles differed significantly between CHD groups and controls, which also had significant differences in coronary vascular lesion count and the degree of vascular stenosis. Moreover, single-point mutation made a very high risk of coronary heart disease. So We have reached a conclusion that the-463 G/A polymorphism of the MPO gene influence the risk of CHD, and is correlated with the extent of coronary artery lesions.