Correlative Study On IL-1β,COX-2,MMP-2 And Premature Rupture Of Membranes

Objective: Through to determine the levels of IL-1βin serum and amniotic fluid, the express of COX-2,MMP-2 in fetal membrane between the premature rupture of membranes and the term-pregnant to analyze the relationship between IL-1βin serum and amniotic fluid and COX-2,MMP-2 in fetal membrane in premature rupture of membranes. Explained the pathogenesis of premature rupture of membranes from the view of cytokine,cyclooxygenase and matrix metalloproteinase. It would provide a theory basement and new train of thought for prevention and cure of premature rupture of membranes.Methods:1. The study objects: 60 pregnant women who had delivered in the Obstetrics of the Second Hospital of HeBei Medical University were selected from September 2006 to July 2007. 20 patients of term premature rupture of membranes (tPROM) were set to the first group and 20 patients of preterm premature rupture of membranes (pPROM) were set to the second group and the other 20 cases of healthy term-pregnant women set to the third group for compared. All the patients were nulliparous women and single birth. All patients had no physical or surgical diseases and other pregnancy complication. 2. sample collecting (1) serum: Approximately 3ml maternal antecubital venous blood were collected before caesarean section and centrifugalized by 2000 r/min for fifteen minutes. Then separated the serum and stored in -20℃refrigerator to be detected. (2) amniotic fluid: Collected 3~5ml amniotic fluid in the caesarean section by amniocentesis, centrifuged and stored in -20℃refrigerator to be detected. (3) fetal membrane: Collected two piece of membrane about 1.5cm×1.5cm close to the crevasse. One piece of the fetal membrane fixed by 10% neutral formalin and embedded in paraffin wax. The other one swilling with phosphate buffer saline for 3 times and freezed in liquid nitrogen immediately then stored in -80℃refrigerator to be detected. 3.The experiment methods: (1) The enzyme linked immunosorbent assay (ELISA) assayed the levels of IL-1βin serum and amniotic fluid in order to show whether there are differences among IL-1βconcentrations of each group and the associativity of the levels of IL-1βbetween serum and amniotic fluid; (2) Fetal membranes histology after hematoryline and eosin (HE) staining was performed to identify as the infection and the noninfection group; (3) Reverse transcription polymerase chain reaction (RT-PCR) technology was used to determine the levels of COX-2mRNA and MMP-2mRNA in fetal membranes. The data was statistical treatment with SPSS13.0 and expressed with mean±standard deviation(x±s). Results were analyzed with use of F test,t test and linear correlation; For these analyses, P<0.05 was considered statistically significant. Results:1. The serum and amniotic fluid concentrations of IL-1βwere significantly higher in patients with premature rupture of membranes than in controls (P<0.01), IL-1βlevels of amniotic fluid were higher in term premature rupture of membranes group then in preterm premature rupture of membranes (P<0.01), but there were not statistics difference in serum (P>0.05).2. The levels of COX-2 mRNA and MMP-2 mRNA were significantly greater in patients with premature rupture of membranes than in controls (P<0.01). Whereas there were not significant differences between the term premature rupture of membranes and the preterm premature rupture of membranes groups. (P>0.05)3. All the objects were dividing to the infection group and the noninfection group according to the histology indicates of the fetal membranes. Infection rate in the premature rupture of membranes group were significantly greater than the control group (P<0.05); no statistically significant differences in infection rate between the term premature rupture of membranes and the preterm premature rupture of membranes groups (P>0.05). The levels of IL-1βin serum and amniotic fluid,COX-2 and MMP-2 mRNA in membranes were significantly higher in the infection group compared with the no infection group (P<0.01), and in the noninfection group, patients with premature rupture of membranes also had a significantly higher levels of IL-1βin serum and amniotic fluid,COX-2 mRNA and MMP-2 mRNA in membranes than the control group (P<0.01), whereas no significant differences between the term premature rupture of membranes and the preterm premature rupture of membranes groups (P>0.05).4. The levels of IL-1βin serum and amniotic fluid were positively correlated(r=0.628, P <0.01), and the levels of IL-1βin serum and amniotic fluid were positively correlated with COX-2 in fetal membranes tissue (r=0.458,P<0.01; r=0. 528,P<0.01). Also the levels of COX-2 mRNA and MMP-2 mRNA in fetal membranes tissue were positively correlated (r=0.826,P<0.01).Conclusion:1. It was found in the study that compared with term-pregnant women, the levels of IL-1βin serum and amniotic fluid,COX-2 and MMP-2 in membranes were significantly higher in the patients of premature rupture of membranes. And there were correlated among them. It illustrate that IL-1,COX-2 and MMP-2 participate the proceed of premature rupture of membranes through to enhance and influence each other.2. The infection rate in the premature rupture of membranes group were significantly greater than the normal pregnancy at term , The levels of IL-1βin serum and amniotic fluid,COX-2 and MMP-2 in membranes were significantly higher in the infection group compared with the noninfection group, and in the noninfection group, patients with premature rupture of membranes also had a significantly higher levels of IL-1βin serum and amniotic fluid,COX-2 and MMP-2 in membranes than the control group. It illustrate that infection participative and promote the premature rupture of membranes for a synergy in the mechanism that originated by IL-1β,COX-2 and MMP-2.3. It indicated in the study that IL-1β,COX-2 and MMP-2 is one of the mechanism of the premature rupture of membranes. It may be an independent factor or take cooperation effect with other associated risk factors, such as infection. Therefore, it can control the genesis of premature rupture of membranes by intercept this passageway in the exploration of diagnose and cure the premature rupture of membranes. It will provide a new direction about the investigation of the prevention and cure of premature rupture of membranes.