Chiara Voltolini

Biomarkers of Spontaneous Preterm Birth: An Overview of The Literature in the Last Four Decades

Background: Understanding spontaneous preterm birth ([PTB] < 37 weeks) is difficult due to heterogeneities associated with multitudes of risk factors and pathophysiological pathways. Several biomarkers are routinely used clinically for predicting preterm labor; however, these factors are either nonspecific or detected too late. Objective: Systematic review of literature on PTB biomarkers in the last 40 years to map out the existing knowledge and gaps in understanding PTB biomarkers. Search strategies: Five electronic databases were searched for human studies on PTB biomarkers published in any language between 1965 and 2008. Selection criteria: The phenotype of interest for final data extraction was exclusively spontaneous PTB with no rupture of membranes. Data extraction included (a) general characteristics of the study (clinical setting, period, and study design), (b) study/participant characteristics (inclusion and exclusion criteria, race/ethnicity, number of participants, gestational age at sampling, (c) characteristics of the biomarker (type, rationale for its selection, type of biological sample, and assay used, and (d) concentration of biomarkers in cases and controls. Data collection and analysis: The search yielded 7255 citations and data were extracted from 217 articles which met our inclusion and exclusion criteria. Main results: A total of 116 different biomarkers were reported and these were assayed 578 times in the 217 included studies. Over two thirds of the 217 studies were performed on North American or European populations. No reliable biomarkers emerged as a risk predictor of PTB. Conclusions: Identifying similar studies on biomarkers for the prediction of PTB was a very challenging task due heterogeneities in study design, sampling issues (types, timing and processing), assay methods, and analyses. Major areas of concern identified in this review include poor phenotype definition, nonideal study designs and poor rationale for biomarker selection and assays and population stratification issues.

Urocortin increases IL-4 and IL-10 secretion and reverses LPS-induced TNF-alpha release from human trophoblast primary cells.

Problem  As urocortin (Ucn) is a placental peptide belonging to the corticotrophin‐releasing hormone (CRH) family that modulates immune function in other biological models, this study evaluated Ucn effects on cytokines secretion from cultured human trophoblast cells.

Understanding Spontaneous Preterm Birth: From Underlying Mechanisms to Predictive and Preventive Interventions

Preterm birth is defined as birth before 37 weeks’ gestational age. With an incidence of 7% to 11%, it is one of the major causes of perinatal mortality and morbidity. Preterm birth is considered a clinical syndrome, which arises from different pathological processes that activate prematurely one or more components of the mechanisms leading to parturition. The premature activation of labor may be caused by multiple pathological conditions; in particular a deregulation of the immune system and an exaggeration of inflammatory processes represent common central mechanisms. The complex pathogenesis, the main risk factors and the different therapeutic options will be described in the present review. Since its incidence is still increasing in the last decades, the goal is to improve the primary and secondary prevention.

A Novel Antiinflammatory Role for the Short-Chain Fatty Acids in Human Labor

Human parturition is an inflammatory process that can be activated prematurely by pathological stimuli. This study investigated the expression of G protein-coupled receptors GPR43 and GPR41 receptors in human uteroplacental tissues and the role of short-chain fatty acids (SCFA) in modulating inflammatory pathways in fetal membranes. Expression of GPR43 and GPR41 was investigated in uteroplacental tissues collected from women delivering at term or preterm after ethical approval and patient informed consent. The effect of SCFA on expression of inflammatory genes was assessed in amnion explants after culture with a mimetic of infection (lipopolysaccharide, LPS). Sodium propionate effect on LPS-induced neutrophil chemotaxis was evaluated by transwell assay. GPR43 and GPR41 mRNA expression was higher in myometrium and fetal membranes collected from women after the onset of labor. GPR43 protein expression localized to immune cells and vascular endothelium in the myometrium and epithelium of fetal membranes. Treatment with LPS significantly increased mRNA expression of GPR43 and inflammatory genes. Cotreatment with LPS and sodium propionate decreased LPS-induced expression of inflammatory genes including IL-6, IL-8, cyclooxygenase-2, IL-1α, intercellular adhesion molecule-1, and platelet endothelial cell adhesion molecule-1 but not IL-1β or lymphocyte function-associated antigen-1. Sodium propionate reduced LPS-induced neutrophil chemotaxis and protein secretion of the neutrophil chemoattractant IL-8. Finally, fetal membrane expression of GPR43 was significantly higher in women delivering preterm with evidence of infection. GPR43-SCFA interactions may represent novel pathways that regulate inflammatory processes involved in human labor. Suppression of inflammatory pathways by SCFA may be therapeutically beneficial for pregnant women at risk of pathogen-induced preterm delivery.

ORIGINAL ARTICLE: Urocortin Increases IL-4 and IL-10 Secretion and Reverses LPS-induced TNF-α Release from Human Trophoblast Primary Cells

Problem  As urocortin (Ucn) is a placental peptide belonging to the corticotrophin‐releasing hormone (CRH) family that modulates immune function in other biological models, this study evaluated Ucn effects on cytokines secretion from cultured human trophoblast cells.

Changes of Placental Kiss-1 mRNA Expression and Maternal/Cord Kisspeptin Levels at Preterm Delivery

Kisspeptin, a placental polypeptide secreted throughout pregnancy, is suggested to play a role at parturition. Here we evaluated whether its placental mRNA expression and maternal/fetal plasma levels change at term and preterm delivery, and its effect on oxytocin secretion from placental explants. Samples were collected from 40 women with singleton pregnancies who underwent elective cesarean section at term (TNL), term vaginal delivery (TD), and preterm vaginal delivery (PTD). Plasma Kisspeptin and oxytocin levels were assessed by ELISA; placental mRNA expression by Real-time quantitative RT-PCR analysis. Placental expression was significantly (P < 0.0001) higher in PTD than TNL and TD and significantly (P < 0.001) higher in TD than TNL. Maternal/fetal plasma concentrations did not differ among the groups, and maternal were significantly higher than fetal levels (P < 0.05). In placental explants increasing doses of kisspeptin did not modify oxytocin secretion. In conclusion, labor is associated with increased placental KiSS-1 expression without changes in maternal/fetal circulation.

Term histologic chorioamnionitis: a heterogeneous condition

A histologic response of histologic chorioamnionitis (HCA) is defined as an intrauterine inflammatory condition characterized by acute granulocyte infiltration into the fetal-maternal or the fetal tissues. Prevalence of HCA is inversely correlated with gestational age, occurring in 50% of preterm birth and in up to 20% of deliveries at term. Regardless of these standard definitions, understanding HCA is challenging as it reflects a heterogeneous condition. A histologic response of HCA from term placentas often does not correspond to a clinical presentation; in this context, the present review aims to analyze main characteristics of this condition, in particular focusing on mechanisms and birth outcomes.

Biochemical and biophysical predictors of the response to the induction of labor in nulliparous postterm pregnancy

OBJECTIVE The objective of the study was to evaluate the clinical, sonographic, and hormonal variables that influence the success of labor induction in nulliparous postterm pregnancies. STUDY DESIGN Fifty nulliparous women with a single postterm pregnancy receiving a slow-release prostaglandin estradiol pessary were prospectively enrolled, and clinical characteristics were analyzed in relation to success of induction of labor. Clinical, sonographic, and hormonal variables were analyzed by univariate statistical analysis and multivariate logistic regression for the prediction of successful induction. RESULTS The group of patients delivering within 24 hours differed significantly from the remaining patients by higher Bishop scores, body mass indices, estradiol serum concentrations, estriol to estradiol ratios, and shorter cervices. The combination of cervical length and estriol to estradiol ratio achieved a sensitivity of 100% (95% confidence interval, 71.3-100%) and a specificity of 94.1% (95% confidence interval, 80.3-99.1%). CONCLUSION Cervical length and the estriol to estradiol ratio represent good predictive indicators of the response to the induction of labor in postterm pregnancies.

Histologic chorioamnionitis at term: implications for the progress of labor and neonatal wellbeing.

Objective: The aim of the present study was to evaluate: i) the rate of histologic chorioamnionitis in relation to the onset of labor and mode of delivery; ii) influence of clinical parameters on the risk of histologic chorioamnionitis in laboring women; iii) neonatal outcome in relation to histologic chorioamnionitis. Methods: A cohort study was conducted on 395 healthy women at term, with singleton uneventful pregnancy, of which 195 with spontaneous onset of labor and 200 with elective cesarean section. All placentas, collected after delivery, were examined for the diagnosis of histologic chorioamnionitis. Mode of delivery, presence of bacterial infection of placenta and membranes, maternal clinical parameters and neonatal outcome were recorded. Results: The rate of histologic chorioamnionitis in women with spontaneous onset of labor was significantly higher than in those experiencing elective cesarean section (28.7% vs. 11.5%). Nulliparity and the duration of labor were independent variables associated with acute histologic chorioamnionitis. The presence of histologic chorioamnionitis did not affect neonatal outcome. Conclusions: The present study showed a highest rate of histological chorionamniositis in women delivering after spontaneous onset of term labor, although the mode of delivery either vaginally or by emergency cesarean section was not influenced by the presence of this pathological condition.

High levels of maternal serum IL-17 and activin A in pregnant women affected by systemic lupus erythematosus.

Citation 
Torricelli M, Bellisai F, Novembri R, Galeazzi LR, Iuliano A, Voltolini C, Spreafico A, Galeazzi M, Petraglia F. High levels of maternal serum IL‐17 and activin A in pregnant women affected by systemic lupus erythematosus. Am J Reprod Immunol 2011; 66: 84–89