Association Of Hypertensive Disorders In Pregnancy With Matrix Metalloproteinase-9Gene-1562C/T Polymorphism

Background and purpose: Hypertensive disorders in pregnancy is apregnancy-specific disease，which is a group of blood pressure in pregnancyclinical syndrome characterized by, a serious threat to maternal and child health,one of the major causes of maternal and perinatal morbidity and mortality inchildren. The morbidity of hypertensive disease was9.4-10.4%, that,s offoreign is7-12%. Metalloproteinases which Gross and Lapire separated fromthe tadpole tail out in1962is a collagenase, able to degrade the collagen matrixtadpole tail, and plays an importantrole in the deformation process of thetadpole. There are more than20species of metalloproteinases whicharedifferent gene products. Matrix metalloproteinases can degrade variouscomponents of the extracellular matrix, and degradation of extracellular matrixin vivo is an important for many physiological processes. The etiology andpathogenesis of hypertensive disorders in pregnancy has not yet beenelucidated, it is reported that MMP-9and tissue inhibitor TIMPs play a veryimportant role in the development of it. The literatures show that expressionlevels in placental of MMP-9of many patients with hypertensive disorders inpregnancy are significantly lower than normal pregnant women. Studies invitro suggest that gene1562C/T may change the expression ofmetalloproteinase-9, resulting in elevated circulating metalloproteinase-9.Abroad clinical studies show that there is a correlation betweenhypertensive disorders in pregnancy and polymorphism1562of MMP-9gene.However, the studies of MMP-9is limited to the foreign national population,due to differences of races on gene expressions, the expressions may bedifferent. Objective: In this study, Inspecting the different MMP-9genepolymorphism of40normal pregnancy and40patients with hypertensivedisorders in pregnancy, we analyze the relationship between MMP-9genepolymorphism and hypertensive disorders in pregnancy, to provide a new,valuable theoretical basis of hypertensive disorders in pregnancy.Materials and Methods: We selected80cases of inpatients for the study(40healthy women with uncomplicated pregnancies,40patients withhypertensive disorders in pregnancy)since February2012January-2014indepartment of Obstetrics and Gynecology of China--Japan Union Hospitalof Jilin University. The diagnostic criteria for hypertensive disorders inpregnancy is based on our national textbooks "Obstetrics and Gynecology"eighth edition classification criteria, and gestational age, number of pregnancy,age and previous history are similar, besides we excluside other medicalcomplications. Healthy control group are people without clinical blood pressure,urine protein, edema, history of hypertension. We analyze the differencebetween patients with hypertensive disorders in pregnancy and healthypregnant. Measurement data are expressed by mean±standard deviation (SD),a P value <0.05was considered statistically significant.Results: The MMP-9-1562C/T genotype frequency distribution inpatients with hypertensive disorders in pregnancy was that CC genotypeoccurred in38patients (95%), CT genotype in2patients (5%), but TT genotypewas not present. The MMP-91562C/T genotype frequencydistribution in healthy individuals of the same region was that CC genotypeoccurred in32individuals (80%), CT genotype in8individuals (20%), TTgenotype in0individuals (0%). There were significant differences inMMP-91562C/T genotype frequency distribution between the two groups(P＜0.05).Conclusion: The MMP-91562C/T gene is polymorphic among the gestational hypertensions. The1562C/T polymorphism in MMP-9gene isassociated with the etiology and pathgenesis of hypertensive disorders inpregnancy.