RESUMEN
Background: Inflammation is a condition that jeopardizes the continuity of pregnancy because it increases the secretion of chemokines that favor the migration of leukocytes from maternal and fetal circulations to the cervix, placenta, and the chorioamniotic membranes. During pregnancy, the level of prolactin (PRL) in the amniotic fluid is high; there is evidence to suggest that PRL contributes to maintain a privileged immune environment in the amniotic cavity. We test the effect of prolactin on the secretion profile of chemokines in human fetal membranes.Methods: Nine fetal membranes collected from healthy nonlabouring cesarean deliveries at term. We placed whole membrane explants in a two-chamber culture system. Choriodecidua and amniotic chambers were pretreated with 250, 500, 1000, or 4000 ng/ml of PRL for 24 h, then choriodecidua was cotreated with 500 ng/ml of lipopolysaccharide (LPS) and PRL for 24 h. We used ELISA to measure secreted levels of four chemokines (RANTES, monocyte chemoattractant protein 1 (MCP-1), MIP-1α, and IL-8) in both amnion and choriodecidua regions.Results: In comparison with basal conditions, LPS treatment induced significantly higher secretion of RANTES, MCP-1, and MIP-1α, but not of IL-8. RANTES was mainly produced by choriodecidua and cotreatment with PRL significantly decreased its LPS-induced secretion. MCP-1 was primarily produced by the amnion and its secretion was only inhibited by 4000 ng/ml of PRL. Both membrane regions produced MIP-1α, which was significantly inhibited at 1000 and 4000 ng/ml PRL concentrations. IL-8 showed no significant changes regardless of PRL concentration.Conclusion: PRL inhibits the differential secretion of proinflammatory chemokines by human fetal membranes.
Asunto(s)
Membranas Extraembrionarias , Lipopolisacáridos , Prolactina , Amnios , Quimiocinas , Femenino , Humanos , Embarazo , Prolactina/fisiologíaRESUMEN
Prolactin (PRL) plays an important role in trophoblast growth, placental angiogenesis and immunomodulation within the feto-maternal interface, where different cell types secrete PRL and express its receptor. During pregnancy, inflammatory signalling is a deleterious event that has been associated with poor fetal outcomes. The placenta is highly responsive to the inflammatory stimulus; however, the actions of PRL in placental immunity and inflammation remain largely unknown. The aim of this study was to evaluate PRL effects on the TLR4/NFkB signalling cascade and associated inflammatory targets in cultured explants from healthy term human placentas. An in utero inflammatory scenario was mimicked using lipopolysaccharides (LPS) from Escherichia coli. PRL significantly reduced LPS-dependent TNF-α, IL-1ß and IL-6 secretion and intracellular levels. Mechanistically, PRL prevented LPS-mediated upregulation of TLR-4 expression and NFκB phosphorylation. In conclusion, PRL limited inflammatory responses to LPS in the human placenta, suggesting that this hormone could be critical in inhibiting exacerbated immune responses to infections that could threaten pregnancy outcome. This is the first evidence of a mechanism for anti-inflammatory activity of PRL in the human placenta, acting as a negative regulator of TLR-4/NFkB signaling.
Asunto(s)
Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/inducido químicamente , Lipopolisacáridos , Placenta/efectos de los fármacos , Prolactina/farmacología , Adulto , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Recién Nacido , Inflamación/metabolismo , Inflamación/prevención & control , Masculino , FN-kappa B/metabolismo , Placenta/citología , Placenta/metabolismo , Embarazo , Tercer Trimestre del Embarazo , Cultivo Primario de Células , Prolactina/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Adulto JovenRESUMEN
Progesterone is an essential hormone that induces deep immune adaptations favoring pregnancy maintenance. We aimed at evaluating the effects of progesterone on the synthesis of pro- and anti-inflammatory cytokines by mononuclear cells isolated from human placental blood stimulated with lipopolysaccharide, emulating an infection-inflammation environment. Mononuclear cells isolated form human placental blood were obtained from nine women undergoing elective cesarean delivery at term (not in labor), isolated by density gradient sedimentation, cultured and co-stimulated with lipopolysaccharide (500 ng/ml) from Escherichia coli in the presence or not of progesterone (0.01, 0.1, or 1.0 µM) for 24 h. Culture supernatants were assayed for pro-inflammatory (IL-1ß, TNFα, IL-6), anti-inflammatory (IL-10) cytokines, chemokines (IL-8, MIP-1α) and total MMP-9 by ELISA. In comparison with basal conditions, lipopolysaccharide treatment induced IL-1ß, TNFα, IL-6, IL-8, MIP-1α, and MMP-9 synthesis. lipopolysaccharide co-treatment with progesterone significantly decreased the bacterial endotoxin-induced IL-1ß, TNF-α, IL-6, IL-8, and MIP-1α secretion. In contrast, co-treatment with progesterone increased the level of IL-10 secreted to the culture medium. The present results support the concept that progesterone can modulate--partially--the inflammatory response of professional immune cells isolated from placental blood. Therefore, progesterone might be part of the natural compensatory mechanism that limits the cytotoxic effects associated with an intrauterine infection process during gestation.
Asunto(s)
Inflamación/inmunología , Leucocitos Mononucleares/inmunología , Placenta/inmunología , Embarazo , Progesterona/metabolismo , Adulto , Células Cultivadas , Citocinas/metabolismo , Femenino , Humanos , Tolerancia Inmunológica , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/inmunología , Adulto JovenRESUMEN
BACKGROUND: During human pregnancy, infection/inflammation represents an important factor that increases the risk of developing preterm labor. The purpose of this study was to determine if pre-treatment with progesterone has an immunomodulatory effect on human placenta production of endotoxin-induced inflammation and degradation of extracellular matrix markers. METHODS: Placentas were obtained under sterile conditions from pregnancies delivered at term before the onset of labor by cesarean section. Explants from central cotyledons of 10 human placentas were pre-treated with different concentrations of progesterone (0.01, 01, 1.0 µM) and then stimulated with 1000 ng/mL of LPS of Escherichia coli. Cytokines TNFα, IL-1ß, IL-6, IL-8, MIP-1α, IL-10 concentrations in the culture medium were then measured by specific ELISA. Secretion profile of MMP-9 was evaluated by ELISA and zymogram. Statistical differences were determined by one-way ANOVA followed by the appropriate ad hoc test; P < 0.05 was considered statistically significant. RESULTS: In comparison to the explants incubated with vehicle, the LPS treatment led to a significant increase in the level of all cytokines. In comparison to the explants treated only with LPS, pre-treatment with 0.01-1.0 µM progesterone significantly blunted (73, 56, 56, 75, 25, 48 %) the secretion of TNF-α, IL-1ß, IL-6, IL-8, MIP-1α, IL-10, respectively. The MMP-9 induced by LPS treatment was inhibited only with the highest concentration of progesterone. Mifepristone (RU486) blocked the immunosuppressive effect of progesterone. CONCLUSIONS: The present results support the concept that progesterone could be part of the compensatory mechanism that limits the inflammation-induced cytotoxic effects associated with an infection process during gestation.
Asunto(s)
Endotoxinas/toxicidad , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/metabolismo , Placenta/metabolismo , Progesterona/farmacología , Adulto , Cesárea , Quimiocina CCL3/biosíntesis , Femenino , Humanos , Interleucina-10/biosíntesis , Interleucina-1beta/biosíntesis , Interleucina-6/biosíntesis , Interleucina-8/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Técnicas de Cultivo de Órganos , Placenta/efectos de los fármacos , Embarazo , Progesterona/fisiología , Factor de Necrosis Tumoral alfa/biosíntesis , Adulto JovenRESUMEN
BACKGROUND AND AIM: Fatty infiltration and fibrosis are major issues in chronic liver disease. Recent reports suggest a role for the endocannabinoid system in these processes. AIM: To characterize localization and expression of CB2 in normal liver and nonalcoholic fatty liver. METHODS: We studied 64 liver biopsies: eight were considered normal; 56 had a diagnosis of nonalcoholic fatty liver disease (NAFLD); 32 with nonalcoholic steatosis and 24 nonalcoholic steatohepatitis (NASH). CB2 immunolocalization was studied in 38 samples in paraffin blocks using immunohistochemistry, and a computerized semiquantitative analysis was carried out. CB2 mRNA expression was assessed through RT-PCR in 26 frozen liver samples and the ratio CB2/beta-actin was used to evaluate differences between groups. Statistical analysis was performed with central tendency measures and the Mann-Whitney U-test. We considered as significant differences those with a P-value <0.05. RESULTS: Neither parenchymal nor nonparenchymal cells in normal liver tissue react towards anti-CB2 antibodies. All the samples from patients with steatosis and nonalcoholic steatohepatitis showed hepatocellular immunoreactivity. Cholangiocytes were positive only in the NAFLD group. Normal liver tissue showed a normalized CB2/beta-actin ratio of 0.001+/-0.01, steatosis 6.52+/-17.3 (P=0.05 vs normal) and NASH 6.49+/-12.2 (P=0.06 vs normal and P=0.6 vs steatosis). CONCLUSION: CB2 receptors are expressed by hepatocytes in nonalcoholic fatty liver disease but not in normal liver.
Asunto(s)
Hígado Graso/metabolismo , Receptor Cannabinoide CB2/metabolismo , Hígado Graso/patología , Hepatitis/metabolismo , Hepatitis/patología , Humanos , Inmunohistoquímica , Hígado/metabolismo , Hígado/patología , Estudios Prospectivos , ARN Mensajero/metabolismo , Receptor Cannabinoide CB2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Distribución TisularRESUMEN
OBJECTIVE: To characterize the molecular nature of the chemotactic signal for sperm contained in human follicular fluid (FF). DESIGN: Follicular fluid was fractionated and several procedures were followed to the physicochemical initial characterization of sperm chemotactic compound(s). MAIN OUTCOME MEASURE: Relative chemotactic activity of each fraction was measured in a double chamber device. RESULTS: Sperm chemotaxis was found to be associated with a lipid-like molecule extracted from FF. Several steroids were assayed individually and only P showed sperm chemotactic properties in dose-response curves. CONCLUSIONS: In this paper we present experimental evidence to support the hypothesis that P, the main steroid component of FF, is a mediator of sperm chemoattraction in human beings.
Asunto(s)
Quimiotaxis , Progesterona/farmacología , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Factores Quimiotácticos/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Líquido Folicular/química , Humanos , Masculino , Progesterona/administración & dosificación , Espermatozoides/fisiologíaRESUMEN
Matrix metallo proteinases (MMP) are the physiological mediators of collagen degradation and its participation in physiopathogenesis of premature rupture of membranes has been suggested by our group. With the idea of defining if some MMP become active active in a coordinated way with labor in fetal membranes, we analyzed enzymatic activity and immunoreactive protein present in extracts of amnion and chorion. It was possible to identify the presence of MMP-9 in extracts of membranes obtained during cesarean sections, without labor, although its activity/quantity was faintly detectable. Instead, extracts of fetal membranes obtained during active labor showed large activity/quantity of this MMP. With a monoclonal antibody, it was possible to show that the active form of MMP-9 could only be found in samples with labor. MMP-9 and its messenger RNA, were localized by immunohistochemistry and in situ hybridization in amniotic epithelium, in some fibroblasts of the compact layer and in trophoblast-like cells in chorion. It is concluded that: 1. Activity and quantity of MMP-9 increase selectively associated to labor; and 2. That this enzyme is expressed by different cellular populations of fetal membranes.