Chronic Hepatitis B Infection is Associated with Decreased Risk of Preeclampsia: A Meta-Analysis of Observational Studies.

BACKGROUND/AIMS: Preeclampsia is a complex multi-system obstetric syndrome and remains one of the leading causes contributing to maternal and perinatal mortality and morbidity. Previous epidemiological studies regarding the association between chronic hepatitis B virus (CHB) infection and the risk of preeclampsia have reported inconsistent results. Therefore, we conducted a meta-analysis to investigate the association between CHB infection and preeclampsia. METHODS: The electronic database was searched until January 1st, 2016. Relevant studies reporting the association between CHB infection and the risk of preeclampsia were included and for further evaluation. Statistical analysis was performed using Stata 10.0 (Stata Corp). RESULTS: Three observational cohort studies and eight case-control studies, including 11566 preeclampsia patients, were identified. A significant negative association between CHB infection and preeclampsia was observed (odds ratio = 0.77, 95% confidence interval, 0.65- 0.90, P=0.002, fixed-effect model). CONCLUSIONS: Findings from our meta-analysis indicate that CHB infection may decrease the risk of preeclampsia in Asian population. Future prospective cohorts in different countries with larger sample sizes are warranted to ascertain the causality and pathophysiological studies are required to explore the possible biological mechanisms involved.

Activation of PAR-1/NADPH oxidase/ROS signaling pathways is crucial for the thrombin-induced sFlt-1 production in extravillous trophoblasts: possible involvement in the pathogenesis of preeclampsia.

BACKGROUNDS/AIMS: Preeclampsia was characterized by excessive thrombin generation in placentas and previous researches showed that thrombin could enhance soluble Fms-like tyrosine kinase 1 (sFlt-1) expression in first trimester trophoblasts. However, the detailed mechanism for the sFlt-1 over-production induced by thrombin was largely unknown. The purpose of this study was to explore the possible signaling pathway of thrombin-induced sFlt-1 production in extravillous trophoblasts (EVT). METHODS: An EVT cell line (HRT-8/SVneo) was treated with various concentrations of thrombin. The mRNA expression and protein secretion of sFlt-1 in EVT were detected with real-time polymerase chain reaction and ELISA, respectively. The levels of intracellular reactive oxygen species (ROS) production were determined by DCFH-DA. RESULTS: Exposure of EVT to thrombin induced increased intracellular ROS generation and overexpression of sFlt-1 at both mRNA and protein levels in a dose dependent manner. Short interfering RNA (siRNA) directed against PAR-1 or apocynin (an inhibitor of NADPH oxidase) could decrease the intracellular ROS generation and subsequently suppressed the production of sFlt-1 at mRNA and protein levels. CONCLUSIONS: Our results suggested that thrombin increased sFlt-1 production in EVT via the PAR-1 /NADPH oxidase /ROS signaling pathway. This also highlights the PAR-1 / NADPH oxidase / ROS pathway might be a potential therapeutic target for the prevention of preeclampsia in the future.

Circulating retinol-binding protein 4 levels in gestational diabetes mellitus: a meta-analysis of observational studies.

Retinol-binding protein 4 (RBP4) is a novel adipocyte-derived cytokine playing an important role in the regulation of energy metabolism and insulin sensitivity. Although the association between RBP4 and metabolic dysfunction is well established, studies on the relationship between circulating RBP4 levels and the risk of gestational diabetes mellitus (GDM) have yielded inconclusive results. We performed a meta-analysis to investigate whether women with GDM had higher circulating RBP4 levels than the normglycemic pregnant women. PubMed, Web of Science and EMBASE were searched up to 1 August 2014. A total of 14 studies comprised of 884 women with GDM and 1251 normglycemic pregnant women were included. The overall results suggested that maternal circulating RBP4 levels were significantly higher in GDM than their normal controls (SMD: 0.49 µg/ml, 95% CI: 0.23-0.75 µg/ml, p < 0.001, random effect model). However, stratified results indicated that this significant difference only existed in the second/third trimester and was limited to Asian populations. Furthermore, subgroup analysis according to matched maternal age and BMI still demonstrated that GDM had higher circulating RBP4 levels than the normal controls. Our findings suggested that Asian women with GDM had increased circulating RBP4 levels in their second/third trimester.

Interrelation Between Fibroblasts and T Cells in Fibrosing Interstitial Lung Diseases.

Interstitial lung diseases (ILDs) are a heterogeneous group of diseases characterized by varying degrees of inflammation and fibrosis of the pulmonary interstitium. The interrelations between multiple immune cells and stromal cells participate in the pathogenesis of ILDs. While fibroblasts contribute to the development of ILDs through secreting extracellular matrix and proinflammatory cytokines upon activation, T cells are major mediators of adaptive immunity, as well as inflammation and autoimmune tissue destruction in the lung of ILDs patients. Fibroblasts play important roles in modulating T cell recruitment, differentiation and function and conversely, T cells can balance fibrotic sequelae with protective immunity in the lung. A more precise understanding of the interrelation between fibroblasts and T cells will enable a better future therapeutic design by targeting this interrelationship. Here we highlight recent work on the interactions between fibroblasts and T cells in ILDs, and consider the implications of these interactions in the future development of therapies for ILDs.

Placental expression of PHLDA2 and IGF2 in selective intrauterine growth restriction in monozygotic twins.

OBJECTIVE: To compare the expression of imprinted genes PHLDA2 and IGF2 in the peripheral blood, placenta and fetal umbilical cord blood from normal single chorionic twins (MCDA) and single chorionic twins combined with sIUGR, in order to explore the pathogenesis relationship between the expression of PHLDA2 and IGF2 with single chorionic twins combined with sIUGR. METHODS: Immunohistochemical method was applied to detect the expression of PHLDA2 and IGF2 in maternal placenta of MCDA and normal MCDA. ELISA method was applied to detect the expression of PHLDA2 and IGF2 in two groups of umbilical cord blood. RESULTS: There was a significant difference in two groups of maternal age and neonatal birth weight (P<0.05). Immunohistochemical results: IGF2 in the normal MCDA maternal placenta was high expression. The number of IGF2-positive cells in MCDA-sIUGR group A1 decreased slightly and the staining decreased slightly. The number of IGF2-positive cells in A2 group was significantly decreased, and the staining was weakened. In normal MCDA placenta, PHLDA2 cells were colorless, or occasionally in pale yellow; the number of PHLDA2 positive cells in MCDA sIUGR A1 group was slightly increased, the staining was light yellow or colorless. In A2 group, the number of positive cells increased significantly, the staining was brown or brownish-yellow. ELISA results showed that there were significant differences in the expression of IGF2 and PHLDA2 between cord blood of MCDA sIUGR and neonatal cord blood (P<0.05). The expression of IGF2 in MCDA sIUGR and normal MCDA twins were also significantly different (P<0.01). CONCLUSION: The differential expression of PHLDA2 and IGF2 may be one of the causes of selective intrauterine growth restriction.

Maternal HCV infection is associated with intrauterine fetal growth disturbance: A meta-analysis of observational studies.

Since the evidence regarding the association between maternal hepatitis C virus (HCV) infection and impaired intrauterine fetal growth had not been conclusive, the aim of the present study was to evaluate the risk of maternal HCV infection in association with intrauterine fetal growth restriction (IUGR) and/or low birth weight infants (LBW). We performed an extensive literature search of PubMed, MEDLINE, and EMBASE through December 1, 2015. The odds ratios (ORs) of HCV infection and IUGR/LBW were calculated and reported with 95% confidence intervals (95% CIs). Statistical analysis was performed using RevMen 5.3 and Stata 10.0. Seven studies involving 4,185,414 participants and 5094 HCV infection cases were included. Significant associations between HCV infection and IUGR (OR = 1.53, 95% CI: 1.40-1.68, fixed effect model) as well as LBW were observed (OR = 1.97, 95% CI: 1.43-2.71, random effect model). The results still indicated consistencies after adjusting for multiple risk factors which could affect fetal growth, including maternal age, parity, maternal smoking, alcohol abuse, drugs abuse, coinfected with HBV/HIV and preeclampsia. Our findings suggested that maternal HCV infection was significantly associated with an increased risk of impaired intrauterine fetal growth. In clinical practice, a closer monitoring of intrauterine fetal growth by a series of ultrasound might be necessary for HCV-infected pregnant population.

Chronic hepatitis B infection and risk of preterm labor: a meta-analysis of observational studies.

Many epidemiological studies have found a positive association between chronic hepatitis B virus (CHB) infection and the risk of preterm labor, but the magnitude of this association varies and independent studies have reported conflicting findings. We performed a meta-analysis to ascertain the relationship between CHB infection and preterm labor. The PubMed and Embase databases were searched up to May 1st, 2014, for relevant observational studies on an association between CHB infection and the risk of preterm labor. Data were extracted and analyzed independently by two authors. The meta-analysis was performed using Stata version 10.0 software. Six observational case-control studies and 4 cohort studies, involving 6781 women with preterm labor, were identified. Based on a random-effects meta-analysis, no association between CHB infection and preterm labor was identified (odds ratio=1.12, 95% confidence interval CI, 0.94-1.33). Our meta-analysis suggested that CHB infection is not associated with an increased risk of preterm labor.