Search

Prolactin (PRL) is a pleiotropic hormone with a key role in pregnancy. In fetal membranes, PRL can regulate the secretion of pro-inflammatory factors, which induces the activation of matrix metalloproteinases (MMPs). The increase and activation of MMPs deregulate the turnover of the extracellular matrix in the fetal membranes, altering its structure and function, causing premature rupture of the membranes and preterm labor. In this work, we evaluate the effect of PRL upon the secretion of MMP-1, MMP-2, MMP-9, MMP-13, and the tissue inhibitors of metalloproteinases (TIMPs) in human fetal membranes after lipopolysaccharide (LPS) challenge. Nine fetal membranes from healthy non-laboring cesarean deliveries at term were cultured in a 2-independent chamber system and pre-treated with 250, 500, 1000 or 4000 ng/ml of PRL for 24 h, then choriodecidual region was stimulated with 500 ng/ml of LPS plus fresh PRL for 24 h. The MMPs and TIMPs secretion were quantified by ELISA, additionally MMP-2 and MMP-9 gelatinolytic activity was measured by zymography. LPS induced the MMP-9 and MMP-1 secretion, but no MMP-2 or MMP-13 in comparison with basal levels. PRL co-treatment decreased the MMP-2, MMP-9 and MMP-1 secretion induced by LPS. The active forms were present in the tissue extract, showing a response consistent with the secretion profile. TIMP-1 and TIMP-2 secretion was decreased after LPS treatment and the PRL co-treatment reverts this effect. The present results support that PRL may favor the balance between these factors involved in the structural maintenance of fetal membranes in an inflammatory event. [ABSTRACT FROM AUTHOR]

Background: Human labor is associated with an inflammatory process that takes place at the maternal–fetal interface, where leukocytes infiltrate and contribute to the local production of effector molecules such as cytokines, chemokines, MMPs, etc. This process may be altered by a low‐grade chronic inflammation, characteristic of obesity, resulting in adverse pregnancy outcomes. In this cross‐sectional pilot study, we analyzed the relationship between maternal adiposity and inflammation‐related gene expression in leukocytes from six healthy women with term pregnancies without labor. Methods: We estimated maternal adiposity and examined the relative expression of 211 inflammation‐related genes in maternal peripheral blood leukocytes (MAT), placental intervillous blood leukocytes (PLA), and choriodecidual leukocytes (CHD) by real‐time qPCR. Finally, we analyzed the correlation between maternal adiposity and gene expression. Results: Participants' adiposity ranged from 27.6% to 61.1% (n = 6). The expression of 23 genes significantly differed (p < 0.05) in MAT, PLA, and CHD leukocytes, most of which code for chemokines and proinflammatory cytokines. Importantly, increasing maternal adiposity correlated (r > 0.7) mostly positively with the expression of genes related to activation, migration, infiltration, and proinflammation in MAT (36 genes) and PLA (31 genes). In contrast, in CHD leukocytes maternal adiposity correlated only negatively with seven genes, involved in migration and infiltration. Conclusion: Our findings suggest that during term pregnancy, increased maternal adiposity may enhance the priming of peripheral leukocytes, while in choriodecidua it may alter leukocyte recruitment and proinflammatory activity. Maternal adiposity must be considered an important variable in further studies that analyze inflammation‐related gene expression in pregnant women. [ABSTRACT FROM AUTHOR]

Objective: Interleukin (IL)-10 is a cytokine with anti-inflammatory properties that plays pivotal roles in immune recognition and maintenance of pregnancy, limiting the harmful effects of pro-inflammatory modulators. The aim of this work was to characterize the contribution of amnion and choriodecidua regions of the human fetal membranes in the production of IL-10 after selective stimulation with Candida albicans, Gardnerella vaginalis and Streptococcus agalactiae. Methods: Pre-labor human fetal membranes were cultured in a two-compartment tissue culture system and stimulated with 1 × 106 CFU/ml of each pathogen added to either the amniotic or choriodecidual region or both. Results: Candida albicans and G. vaginalis were the pathogens most effective in inducing IL-10 secretion, increasing 20 and 10 times, respectively, the levels of this cytokine in the choriodecidual compartment. Stimulation with S. agalactiae was effective only in the choriodecidual region, increasing two times IL-10 concentration. Conclusions: Synthesis and secretion of IL-10 in response to three different pathogens associated with intrauterine infection and preterm birth are differential and depend on the nature of the microorganism and initial contact region. [ABSTRACT FROM AUTHOR]

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The human labor is an inflammatory process invading leukocytes modulated by gestational tissues. The local increase of cell adhesion molecules (CAMs) promotes the permanence of these leukocytes in the coriodecidua. Gestational tissues express ICAM-1, while circulating leukocytes expressing its ligand Mac-1., Objective: To analyze, first, if the expression of CAMs in the fetal membranes is associated with progress of gestational age, and second, the expression of CAMs on circulating leukocytes in the uterus (placenta)., Material and Method: original and closed study conducted at the Instituto Nacional de Perinatologia Isidro Espinosa de los Reyes (Mexico City). We included samples from healthy women between 15 and 44 years of age with term pregnancies (> or =37 weeks gestation)., Results: Real time PCR analysis showed that the expression of CAMs in the fetal membranes remained constant before labor. ICAM3 and ICAM1 tended to increase during labor, while ICAM2, VCAM1, SELE and SELP decrease with advancing gestational age. Placental leukocytes showed a clear increase in the expression of ITGAM (Mac-1) during labor., Conclusions: These results show that the maternal-fetal interface expresses a specific combination of CAMs during labor, including ICAM1, ICAM-3 and Mac-1. The expression of these molecules could promote the retention of leukocytes in the local tissues to modulate the local inflammatory microenvironment during human labor.

Background: Physical and structural chorioamniotic membranes integrity is due to a precise process of synthesis and degradation of collagen; surrounding collagenolitic activity raises during labor, what leads to a structural loss and mechanical resistance weakening, the main cause of its rupture under physiological and pathological conditions. Understanding of its three-dimensional structure is essential to characterize normal and pathological labor., Objective: To analyze three-dimensional structure of human chorioamniotic membranes at gestational term., Material and Methods: Descriptive study to analyze the distribution of collagens type I, II and IV in human chorioamniotic membranes at term (37 to 40 gestational weeks) without labor by means of confocal and electronic scan microscopy., Results: Cells' amnios shapes a homogeneous epithelium without a close intercellular contact (classic epithelium) what may contribute to transmembranal diffusion molecules' transport. Amnios connective tissue is too a complex fibrilar net of type I collagen, structurally supported by type IV collagen. On the contrary, corion has a great amount of cells in close contact, with a few fibers of type I and II collagen, and almost none of type IV collagen cells., Conclusion: Three-dimensional analysis of chorioamniotic membranes connective tissue, particularly amnios, allows to understand the main role of type IV collagen on supporting its structure, as well as collagenolitic enzymes in its degradation and rupture under normal and pathological conditions.

Objective: To identify a specific microenvironment in direct contact with fetal membranes where effector molecules acumulate, aiming to degrade the components of its extracellular matrix during labor., Type of Study: Experimental, analytic, longitudinal and prospective., Materials and Methods: Blood samples were collected from maternal, fetal and choriodecidual compartments, and mononuclear cells were isolated. Part of these cells was stained with antibodies to determine leukocyte subpopulations by flow cytometry. The other part was cocultured for 12 h with amniochorion explants. After coculture, MMP-9 was identified on the mononuclear cells by immunofluorescence. IL-1beta and TNF-alpha were determined in the supernatants by ELISA. Three independent experiments were carried out with duplicates and analyzed with Mann-Whitney's U test., Results: Although there were no significant differences in the mononuclear cell subpopulations from the three compartments, MMP-9 production was higher in choriodecidual cells than in those of the maternal and fetal compartments. Furthermore, IL-1beta and TNF-alpha were significantly more abundant in cocultures with choriodecidual cells compared with the other two compartments., Conclusions: During labor, choriodecidual cell subpopulations are not phenotypically different from those of the maternal or fetal compartments, but they are regarding MMP-9 production, which suggests that the environment surrounding chorioamniotic membranes enhances the synthesis of this enzyme, thus promoting degradation of connective tissue.