摘要
目的探讨子痫前期胎盘组织中生长阻滞和DNA损伤45α（growtharrestandDNAdamage—inducible45alpha，Gadd45a）基因和p38丝裂原活化蛋白激酶（p38mitogen-activatedproteinkinase，p38MAPK）信号分子的表达，及其与血清中可溶性血管内皮生长因子受体-1（solublevascularendothelialgrowthfactorreceptor-1，sFlt-1）和可溶性endoglin（solubleendoglin，sEng）的相关性分析。方法选择2009年9月至2010年3月在重庆医科大学附属第一医院住院分娩的孕妇54例为研究对象，按病情分为子痫前期轻度组20例、子痫前期重度组16例，以足月择期剖宫产孕妇18例为对照组。采用免疫组织化学SP法检测Gadd45α及磷酸化p38MAPK（phospho—p38MAPK，P—p38MAPK）蛋白在各组胎盘组织中的定位；实时荧光定量PCR检测各组胎盘组织中Gadd45amRNA水平；Western印迹法检测各组胎盘组织中Gadd45α蛋白的表达水平、p38MAPK及p-p38MAPK的蛋白表达差异；双抗体夹心酶联免疫吸附法检测各组孕妇血清样本中sFh-1及sEng的含量，并进行单因素方差及LSD-t检验分析。结果（1）免疫组织化学检测Gadd45α与P—p38MAPK蛋白均定位于胎盘滋养层细胞胞质及胞核、血管内皮细胞胞核及少量间质细胞胞核。（2）子痫前期重度及轻度组Gadd45utuRNA相对表达水平（3．33±0．13和2．10±0．11）较正常对照组（1．01±0．18）明显上调，且子痫前期重度组高于轻度组，两两比较差异均有统计学意义（P〈O．05）。（3）Western印迹法检测正常对照组、子痫前期轻度组及重度组患者胎盘组织中Gadd45a蛋白表达水平分别为0．22±0．11、0．65±0．15、1．34±0．17；p-p38MAPK蛋白的表达水平分别为0．32士0．08、0．72±0．12、1．45±0．21，两两比较差异均有统计学意义（P〈O．05）；p38MAPK蛋白水平组间比较差异无统计学意义（P〉O．05）。（4）子痫前期轻度组、重度组孕妇血清sFlt-1、sEng水平明显高于正常对照组，且子痫前期重度组高于轻度组，两两比较差异均有统计学意义（P〈0．05）。（5）各组Gadd45α蛋白水平与孕妇血清中的sFlt-1、sEng含量呈正相关（r分别为0．88和0．87，P均〈0．05）。结论Gadd45α在子痫前期患者胎盘组织中的表达明显升高，其可能通过调控p38MAPK信号转导通路，诱使循环中的sFlt-1、sEng释放增加，从而加重胎盘血管重铸障碍和抑制滋养细胞浸润，参与子痫前期的发病。
Objective To evaluate the expression of Gadd45α and p38 MAPK in placentas and the correlations of Gadd45α protein and serum soluble vascular endothelial growth factor receptor-1 （sFlt-1） and soluble endoglin （sEng） in preeciampsia（PE）. Methods Fifty-four pregnant women who delivered fromSeptember 2009 to March 2010 in the First Affiliated Hospital of Chongqing Medical University were chosen as the subjects. They were classified into mild preeclampsia group （n = 20）, severe preeclampsia group （n= 16） and the control group （normal pregnant women underwent elective cesarean sections at term without labor and perinatal complications, n = 18）. Western blot and immunohistochemistry were employed to determine the expression and localization of Gadd45α and p-p38 MAPK protein respectively. Gadd45α mRNA level was determined by quantitative real-time PCR. The levels of scum sFlt-1 and sEng were measured by enzyme-linked immunosorhent assay （ELISA）. One-way ANOVA and LSD-t test were applied for statistical analysis. Results （1） Immunobistochemistry identified that the positive stained cells were mostly located in trophoblast cells in normotensive placentas, whereas in preeclamptic placentas Gadd45α protein and p-p38 MAPK protein were detected in trophoblast and endothelial cells, as well as a few stromal cells at increased levels. （2）The mRNA levels of Gadd45α was significantly elevated in mild and severe preeclampsia groups compared to the control group （2.10 ± 0. 11 and 3.33 ± 0.13 vs 1.01±0.18, P〈0.05）, and Gadd45αmRNA level in severe group was significantly higher than in mild group （P〈0.05）. （3）The data of Western blot revealed that the Gadd45α protein levels in each group were 0.22 ± 0.11, 0.65 ± 0.15 and 1.34 ±0.17, respectively, with significant differences between each group（P〈0.05）. The p-p38 MAPK protein levels in each group were 0. 32 ± 0. 08 , 0. 72±0.12 and 1.45 ±0.21, respectively, with significant differences between each group （P〈 0.05）. p38 MAPK protein levels in the total groups showed no difference（P〉0.05）. （4）Compared with the control group, sFlt-1 and sEng concentrations in maternal circulation were significantly increasing in mild and severe preeclampsia groups, and concentrations in severe group were significantly higher than those in mild group （P〈0.05）. （5） There were positive correlations between Gadd45α protein levels and the concentrations of serum sFh-1 and sEng in each group（ r= 0.88 and 0.87, respectively all P〈0.05）. Conclusions Upregulation of Gadd45α in preeclampsia placentas may play an important role in the pathogenesis of preeclampsia. It may induce the increased maternal serum levels of sFh-1 and sEng by activating p38 MAPK signaling pathway, leading to deficient cytotrophoblastic invasion and abnormal placental vascular reconstruction during pregnancy.
出处
《中华围产医学杂志》
CAS
2011年第7期396-402,共7页
Chinese Journal of Perinatal Medicine
基金
基金项目：国家自然科学基金（81070502）
