米非司酮对人早孕绒毛组织核转录因子-κB表达的影响

目的 探讨米非司酮对人早孕绒毛组织中核转录因子-κB(nf-κB)表达的影响.方法 人工流产组早孕绒毛18例和药物流产组早孕绒毛22例,应用逆转录聚合酶链反应(RT-PCR)和免疫组织化学技术分别测定两组早孕绒毛组织中NF-κB蛋白和mRNA的分布与含量.结果 药物流产组早孕绒毛组织中NF-κB mRNA表达量与人工流产组相比下调明显(P<0.01);药物流产组早孕绒毛细胞滋养层细胞中NF-κB蛋白表达与人工流产组相比明显下调(P<0.05).结论 米非司酮引起早孕绒毛NF-κB表达降低,可能是米非司酮终止早孕的机理之一.     

Toxic effects of low doses of Bisphenol-A on human placental cells

Humans are exposed daily to a great number of xenobiotics and their metabolites present as pollutants. Bisphenol-A (BPA) is extensively used in a broad range of products including baby bottles, food-storage containers, medical equipment, and consumer electronics. Thus, BPA is the most common monomer for polycarbonates intended for food contact. Levels of this industrial product are found in maternal blood, amniotic fluid, follicular fluid, placental tissue, umbilical cord blood, and maternal urine. In this study, we investigated toxic effects of BPA concentrations close to levels found in serum of pregnant women on human cytotrophoblasts (CTB). These cells were isolated from fresh placentas and exposed to BPA for 24 h. Our results showed that very low doses of BPA induce apoptosis (2 to 3 times) as assessed using M30 antibody immunofluorescent detection, and necrosis (1.3 to 1.7 times) as assessed through the cytosolic Adenylate Kinase (AK) activity after cell membrane damage. We also showed that BPA increased significantly the tumor-necrosis factor alpha (TNF-α) gene expression and protein excretion as measured by real-time RT-PCR and ELISA luminescent test, respectively. Moreover, we observed that induction of AK activation and TNF-α gene expression require lower levels of BPA than apoptosis or TNF-α protein excretion. Our findings suggest that exposure of placental cells to low doses of BPA may cause detrimental effects, leading in vivo to adverse pregnancy outcomes such as preeclampsia, intrauterine growth restriction, prematurity and pregnancy loss.     

醋酸棉酚对离体大鼠黄体和人蜕膜、滋养层细胞的影响

以细胞分泌功能和存活率为指标,观察了醋酸棉酚对无血清培养的大鼠黄体和人蜕膜、滋养层细胞的直接损伤作用和可能的作用途径。结果表明:醋酸棉酚对黄体细胞有直接杀伤作用,LD₅₀为:1.6(0.4～2.9)μg·mL^-1。在非致死剂量(0.5μg·mL^-1)下,醋酸棉酚显著抑制黄体细胞基础孕酮分泌,但不能显著抑制hCG,Forskolin的促孕酮作用和3β-HSD的活性。此外,醋酸棉酚对蜕膜细胞和滋养层细胞也有直接杀伤作用,其LD₅₀分别为:3.5(0.4～6.6)μg·mL^-1,4.1(0.6～7.6)μg·mL^-1。本文结果提示,直接杀伤黄体,蜕膜和滋养层细胞并影响孕酮合成是醋酸棉酚抗生育的重要作用环节。     

Dissociation between increased apoptosis and expression of the tumor necrosis factor-alpha system in term placental villi with preeclampsia

OBJECTIVE: To analyse in situ the placental expression of tumor necrosis factor-alpha (TNF-alpha), its receptors TNFRp55 and TNFRp75, and apoptosis in normotensive and preeclamptic pregnancies. DESIGN AND METHODS: We simultaneously analyzed the immunostaining of TNF-alpha, its receptors and apoptosis in term placentas of 15 patients with preeclampsia and 15 normotensive pregnant women as controls. RESULTS: In normotensive villi TNF-alpha and TNFRp75 were expressed more in syncytiotrophoblasts than cytotrophoblasts or stromal cells, and were almost absent in endothelial cells. TNFRp55 was expressed uniformly in all types of placental cells. Apoptosis was more marked in syncytiotrophoblasts than cytotrophoblasts. In preeclamptic trophoblasts apoptosis was exaggerated whereas expression of TNF-alpha and its receptors remained unchanged. CONCLUSIONS: Placental expression of TNF-alpha and TNFRp75 appear inter-adaptative and follow the same pattern, whereas TNFRp55 and TNF-alpha appear independent. In addition, the exaggerated apoptosis of preeclamptic trophoblasts may be dependent on factors other than the TNF-alpha system alone.     

体外培养人胎盘滋养层细胞内吞丙型肝炎病毒过程的电镜观察

目的 探讨丙型肝炎病毒（HCV）感染体外分离培养人胎盘滋养层细胞的可能机制，观察HCV感染滋养层细胞后在细胞内的具体定位。方法采用胰蛋白酶消化法及Percoll密度梯度分离法分离培养人胎盘组织中滋养层细胞后，以HCVRNA阳性血清对滋养层细胞进行体外感染实验，不同时间终止实验，制备电镜标本，透射电镜观察。结果HCV感染滋养层细胞的过程中有吞噬小泡形成，形态学上符合被覆小凹的特点；感染后HCV病毒样颗粒多定位于粗面内质网附近。结论HCV可以感染滋养层细胞，其感染过程可能是被覆小凹介导的内吞过程。本研究提供了HCV体外感染人胎盘滋养层细胞具体方式的形态学资料，对HCV宫内传播机制的进一步研究奠定了实验基础。     

体外感染实验探讨丙型肝炎病毒的ADE分子机制

目的研究丙型肝炎病毒(HCV)在感染人滋养层细胞的过程中是否存在抗体依赖性感染增强(ADE)作用,以探讨HCV母婴传播的分子机制。方法将HCV阳性血清以4种不同方式感染人滋养层细胞,以免疫电镜观察HCV病毒颗粒在滋养层细胞中的表达,应用RT-PCR法、免疫组化法检测细胞内外的HCVRNA正链、负链,HCVNS5、NS3及C区抗原。结果在滋养层细胞胞浆内发现了HCV病毒颗粒,HCVRNA正链、负链,HCVNS5、NS3、C区抗原仅在全血清感染细胞内或上清中间断测得。结论HCV可以在滋养层细胞中复制。HCV感染滋养层细胞的过程中存在ADE机制,抗体和补体均参与了HCV的跨膜转运过程。     

Serum from women with preeclampsia partially corrects the abnormal in vitro prostacyclin secretion of preeclamptic villous cytotrophoblasts but not that of prostaglandin E2 or endothelin-1

OBJECTIVE: This study was conducted (1) to determine in vitro placental villous cytotrophoblast secretion of prostacyclin, prostaglandin E₂, and endothelin-1, (2) to examine the effect of serum from normal and preeclamptic women on secretion of these vasoactive substances, and (3) to determine whether responses to these sera by cytotrophoblasts from preeclamptic pregnancies are different from those of normal pregnancies. STUDY DESIGN: Cytotrophoblasts isolated from human placentas collected at cesarean section from normal and preeclamptic women were incubated for 20 hours in 20% (vol/vol) sera from preeclamptic or gestational age–matched normal pregnant women. Levels of prostacyclin (measured as 6-keto-prostaglandin F_1α), prostaglandin E₂, and endothelin-1 were measured in cytotrophoblast supernatants. RESULTS: In normal pregnancy sera preeclamptic cytotrophoblasts secreted significantly lower amounts of prostacyclin and prostaglandin E₂ but higher amounts of endothelin-1 than did normal cytotrophoblasts. In preeclamptic sera the abnormality of prostacyclin secretion by preeclamptic cytotrophoblasts was partially corrected, but there was no effect on prostaglandin E₂ or endothelin-1 secretion. Preeclamptic sera had no effect on secretion by normal cytotrophoblasts. CONCLUSIONS: The differences between normal and preeclamptic cytotrophoblasts in prostacyclin, PGE₂, and endothelin-1 secretion and in response to preeclamptic serum suggest altered arachidonic acid metabolism in preeclampsia.(Am J Obstet Gynecol 1997;177:1491-5.)     

妊娠期子宫蜕膜淋巴管研究进展

近年通过对淋巴管透明质酸受体-1和肾小球足突细胞膜蛋白等淋巴管表面标志的研究发现,妊娠期子宫内膜(蜕膜)也有大量淋巴管出现。而体内外实验表明,胎盘滋养细胞可能参与蜕膜淋巴管的形成,并起调控作用。这种蜕膜淋巴管的功能主要是:影响螺旋动脉血流、激活免疫细胞以及参与母胎免疫耐受等。关于其产生和作用的机制将是未来研究的方向。     

人滋养层细胞内丙型肝炎病毒样颗粒的免疫电镜形态学研究

目的：应用免疫电镜技术观察体外培养的人胎盘滋养层细胞感染丙型肝炎病毒（HCV）情况。方法：采用胰蛋白酶消化法及Percoll密度梯度分离法分离培养人胎盘组织中滋养层细胞，以HCV RNA阳性血清对滋养层细胞进行体外感染实验，胶体金免疫电镜检测滋养层细胞内的HCV病毒颗粒，逆转录聚合酶链反应（RT—PCR）定性检测滋养层细胞内HCV RNA。结果：体外培养的人胎盘滋养层细胞内可观察到胶体金颗粒吸附的病毒样颗粒，形态及直径符合HCV特点。RT—PCR定性检测结果阳性，进一步证文所观察到的病毒样颗粒为HCV。结论：HCV可感染体外培养的人胎盘滋养层细胞。     

The thrombogenic effect of an inflammatory cytokine on trophoblasts from women with preeclampsia

OBJECTIVE: This study was undertaken to investigate whether the increased thrombogenic potential of cytotrophoblastic cells of women with preeclampsia can be accounted for by increased rates of apoptosis. STUDY DESIGN: Cytotrophoblasts were isolated from the placenta of (a) nulliparous women without hypertensive disease who were delivered at term and (b) nulliparous women with preeclampsia. The cytotrophoblasts were identified by morphology, and cytokeratin and gonadotropin-releasing hormone positivity. The inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) was added to cytotrophoblasts in vitro and incubated for 24 hours. Tissue factor antigen, activity, and amount of apoptosis were evaluated both before and after TNF-alpha stimulation. RESULTS: TNF-alpha simulation significantly increased tissue factor activity both in the cytotrophoblasts of women with (0.08 +/- 0.04 pmol/min/10 6 cells to 0.53 +/- 0.19 pmol/min/10 6 cells) and without (0.07 +/- 0.04 pmol/min/10 6 cells to 0.30 +/- 0.16 pmol/min/10 6 cells) preeclampsia. TNF-alpha stimulation of the cytotrophoblasts also significantly increased tissue factor antigen in the cytotrophoblasts of both groups of women (3.6 +/- 0.9 fmol/10 6 cells to 34.0 +/- 7.5 fmol/10 6 cells, and 7.5 +/- 1.4 fmol/10 6 cells to 25.4 +/- 2.2 fmol/10 6 cells, respectively). For both tissue factor antigen and activity, the magnitude of increase after stimulation was significantly greater in the preeclamptic cytotrophoblasts. In contrast, both normal and preeclamptic cytotrophoblasts showed similar increases in their apoptotic indices (approximately 2-fold) after induction by TNF-alpha. CONCLUSION: The greater response of tissue factor activity and antigen to TNF-alpha by preeclamptic cytotrophoblasts cannot be accounted for by the increase in apoptosis. These data suggest that preeclamptic cytotrophoblasts are inherently more thrombogenic and more sensitive to TNF-alpha stimulation.