Cytokine gene polymorphisms in recurrent spontaneous abortions: a comprehensive review

Investigating the molecular mechanism of traditional Chinese medicine for the treatment of placental syndromes by influencing inflammatory cytokines using the Mendelian randomization and molecular docking technology

Introduction

Placental syndromes, which include pregnancy loss, preterm birth, gestational diabetes mellitus (GDM), and hypertensive disorders in pregnancy (HDP), have a strong association with disorder inflammatory reactions. Nonetheless, the exact causal relationship has not been established. This study aims to investigate the causal relationship between placental syndromes and inflammatory cytokines utilizing Mendelian randomization (MR). Additionally, we examined the interaction between small molecular compounds derived from traditional Chinese medicine and inflammatory cytokines using molecular docking method.

Methods

After obtaining the data of inflammatory cytokines and placental syndromes, as well as establishing single nucleotide polymorphisms (SNPs), we employed the inverse variance weighted (IVW) method to assess the causal relationship. We also accessed the heterogeneity and the horizontal pleiotropy of these data. The "ClusterProfiler" R package was utilized for Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) term analyses. The protein-protein interaction (PPI) network was constructed using STRING database. AutoDock Vina software was used for molecular docking, and Discovery Studio 2019 was used for visualization purposes.

Results

We found that the growth regulated oncogene A (GROA) and interleukin-9 (IL-9) were associated with the development of pregnancy hypertension, whereas interleukin-10 (IL-10) and hepatocyte growth factor (HGF) were linked to the occurrence of preeclampsia. Moreover, there were correlations observed between interleukin-18 (IL-18), IL-10, macrophage colony-stimulating factor (MCSF), and platelet-derived growth factor BB (PDGFbb) in cases of chronic hypertension combined with pregnancy (CHP). Additionally, macrophage migration inhibitory factor (MIF) exhibited a connection with GDM, and TNF related apoptosis inducing ligand (TRAIL) demonstrated a causal relationship with preterm birth. It is plausible to suggest that interleukin-1β (IL-1β) might contribute to the promotion of pregnancy loss. All of the binding free energy values of small molecular compounds with inflammatory cytokines were below -5.0 kcal/mol. Furthermore, all of the RMSD values were less than 2.

Conclusions

GROA, IL-1β, IL-9, IL-10, IL-18, MIF, MCSF, HGF, PDGFbb and TRAIL were found to be causally associated with placental syndromes. Molecular docking analysis revealed that small molecular compounds, such as puerarin, magnolol, atractylenolide I, paeoniflorin, tumulosic acid and wogonin, are closely bound to these inflammatory cytokines.

Genes of Inflammation and Placental Function GWAS Associated with Idiopathic Recurrent Miscarriage in the Kazakh Population

BACKGROUND

The loss of two or more pregnancies is considered recurrent miscarriage (RM). One of the causes of this pathology is the occurrence of mutations both in pleiotropic and pathway-specific regulators and in structural genes. The simplest type of such mutations is single nucleotide polymorphisms.

AIMS

The aim of the study is to study the relationship between gene polymorphisms of anti- and pro-inflammatory cytokines - interferon-gamma (T874A), interleukin (IL1B) (C3954T), IL6 (G572C) and IL10 (G1082A); placental function, apoptosis and angiogenesis - apolipoprotein C-III (APOC3) (G5163C), kinase insert domain receptor (A1719T, G1192A), P53 (Arg72Pro) and signal transducer and activator of transcription 3 (STAT3) (C1697G) with the development of idiopathic RM (iRM) in the Kazakh population.

SETTINGS AND DESIGN

This was a case-control study.

MATERIALS AND METHODS

Molecular genetic studies were performed by TaqMan using a single site-specific amplification and real-time genotyping method in 302 women with iRM and 300 with normal reproduction. DNA isolation from the biomaterial was carried out using kits containing binding magnetic particles. Both samples were analysed for alleles and genotypes for the studied polymorphisms.

STATISTICAL ANALYSIS USED

For statistical data processing, Pearson's criterion, confidence interval (CI) and probability value were taken into account.

RESULTS

It was found that the carriage of unfavourable genotypes (G/C, C/C) for the G5163C polymorphism of the APOC3 gene increases the risk of developing iRM by three times (odds ratio = 3.0; 95% CI = 2.24-4.07). Other studied polymorphisms in the genes of ILs, interferon, P53 proapoptotic protein, kinase domain receptor and STAT3 transcription activator were not associated with RM.

CONCLUSION

Significant associations of APOC3 gene genotypes with the development of iRM in the Kazakh population indicate the involvement of the placental system, which is realised by vascularisation defects and defective embryo implantation and leads to early pregnancy termination.

Comprehensive molecular expression profiling of SARS-CoV-associated factors in the endometrium across the menstrual cycle and elevated susceptibility in women with recurrent pregnancy loss

Objective: To evaluate the dynamic expression profiling alterations of SARS-CoV-2-associated molecules within the fertile human endometrium throughout the menstrual cycle. Furthermore, to explore the inherent vulnerability of the endometrium to SARS-CoV-2 infection among women experiencing recurrent pregnancy failure, including both recurrent implantation failures (RIF) and recurrent pregnancy losses (RPL). Method: The present study employed multiple datasets to investigate the expression patterns of SARS-CoV-2-associated genes. Firstly, a single-cell RNA-sequencing dataset comprising endometrial samples from 19 healthy women across the menstrual cycle was utilized. Additionally, two microarray datasets encompassing 24 women with RIF, and 24 women with RPL during the peri-implantation phase were included. To complement these analyses, immunohistochemical (IHC) staining was performed on endometrial samples collected from 30 women with RIF, 30 women with RPL, and 20 fertile controls recruited specifically during the implantation period. Results: The investigation revealed a moderate expression percentage of CTSL (22%), TMPRSS4 (15%), FURIN (16%) and MX1 (9%) in endometrium. Conversely, the expression percentages of ACE2 (1%) and TMPRSS2 (4%) were relatively low. Notably, the expression of BSG exhibited an increment towards the window of implantation, reaching its peak during the middle secretary phase. Furthermore, a significant reduction (p < 0.05) in TMPRSS2 expression was observed in the RIF group compared to the control group. While the expression of BSG was significantly increased (p < 0.05) in the RPL group, findings that were corroborated by the IHC staining results. Conclusion: The findings of this study indicate a noteworthy upregulation of BSG expression in the endometrium of women with RPL. These results suggest an augmented susceptibility of endometrium to SARS-CoV-2 infection, potentially contributing to unfavorable pregnancy outcomes.

LDHA deficiency inhibits trophoblast proliferation via the PI3K/AKT/FOXO1/CyclinD1 signaling pathway in unexplained recurrent spontaneous abortion

Dysregulated trophoblast proliferation, invasion, and apoptosis may cause several pregnancy-associated complications, such as unexplained recurrent spontaneous abortion (URSA). Recent studies have shown that metabolic abnormalities, including glycolysis inhibition, may dysregulate trophoblast function, leading to URSA. However, the underlying mechanisms remain unclear. Herein, we found that lactate dehydrogenase A (LDHA), a key enzyme in glycolysis, was significantly reduced in the placental villus of URSA patients. The human trophoblast cell line HTR-8/SVneo was used to investigate the possible LDHA-mediated regulation of trophoblast function. LDHA knockdown in HTR-8/SVneo cells induced G0/G1 phase arrest and increased apoptosis, whereas LDHA overexpression reversed these effects. Next, RNA sequencing combined with Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that the PI3K/AKT signaling pathway is potentially affected by downstream genes of LDHA. Especially, we found that LDHA knockdown decreased the phosphorylation levels of PI3K, AKT, and FOXO1, resulting in a significant downregulation of CyclinD1. In addition, treatment with an AKT inhibitor or FOXO1 inhibitor also verified that the PI3K/AKT/FOXO1 signaling pathway influenced the gene expression of CyclinD1 in trophoblast. Moreover, p-AKT expression correlated positively with LDHA expression in syncytiotrophoblasts and extravillous trophoblasts in first-trimester villus. Collectively, this study revealed a new regulatory pathway for LDHA/PI3K/AKT/FOXO1/CyclinD1 in the trophoblast cell cycle and proliferation.

Impact of Vitamin C on Gene Expression Profile of Inflammatory and Anti-Inflammatory Cytokines in the Male Partners of Couples with Recurrent Pregnancy Loss

Immune system disorders and increased inflammation in the male reproductive system can lead to fetal risk in the early stages of development and implantation. Antioxidants such as vitamin C can play a protective role against sperm inflammatory reactions. This study aimed to evaluate the effect of vitamin C on the expression of inflammatory and anti-inflammatory cytokine genes in the male partners of couples with recurrent pregnancy loss. In this randomized clinical trial, twenty male partners of couples with RPL were examined for sperm parameters and expression profile of some inflammatory and anti-inflammatory cytokine genes before and after treatment with vitamin C. There was a statistically significant higher rate of normal morphology and sperm concentration in each patient before and after treatment with vitamin C (p ≤ 0.05). The mRNA levels of interleukin 6 and tumor necrosis factor-alpha were significantly decreased in the sperm of patients after treatment with vitamin C compared to before treatment. In contrast, the gene expression levels of interleukin 4 and transforming growth factor-beta showed a significant increase in the sperm of patients after treatment with vitamin C. Oral daily administration of vitamin C may be effective in the fertility potential of male partners of couples with RPL not only through the improvement of the sperm parameters but also by modulating the expression profile of inflammatory and anti-inflammatory genes. Further studies on protein levels are needed to clarify the role of TNF-⍺ and IFN-γ as a prognostic value in evaluating the recurrent abortion risk in infertile male partners. This trial is registered with IRCT20180312039059N1.

The role of IP-10 and its receptor CXCR3 in early pregnancy

The local immune microenvironment of the uterus plays an important role in a successful pregnancy. IP-10 (CXCL10) has been extensively studied in many immune-related diseases. However, the immune role of IP-10 in early pregnancy has not been fully recognized. This study mainly investigated the role of pro-inflammatory chemokine IP-10 in pregnancy. The levels of IP-10 and its receptor chemokine receptor 3 (CXCR3) were lower in the decidual tissues of an abortion-prone mice than in normal pregnant mice. Meantime, the expression of IP-10 and CXCR3 was higher in the decidual tissues of early pregnant women than in the endometrial tissues of non-pregnant women. IP-10 promoted the production of interleukin 17 (IL-17) and interferon gamma (IFN-γ), and also promoted the migration and differentiation of uterine decidual T cells to type 1 T helper (Th1) cells and Th17 cells. The abortion rate of early pregnant mice increased but the number of CD49b+, CD11b+, and CD3ε+ cells in the decidual tissues decreased upon treatment with anti-IP-10 antibody. Moreover, anti IP-10 antibody decreased the expression of RANTES but increased the expression of anti-inflammatory cytokines IL-6 and IL-10. A successful pregnancy requires the participation of IP-10. IP-10 participates in formation of the pro-inflammatory immune microenvironment during early pregnancy by regulating the distribution of immune cells and promoting the production of pro-inflammatory cytokines.

Systematic biological and proteomics strategies to explore the regulation mechanism of Shoutai Wan on recurrent spontaneous Abortion's biological network

ETHNOPHARMACOLOGICAL RELEVANCE

Shoutai Wan (STW) is a classic herbal formula for the treatment of recurrent spontaneous abortion (RSA), and clinical studies have shown the effectiveness of STW on RSA. However, the molecular mechanism of STW treatment of RSA is still unclear.

METHODS

(1) Animal experiments: The normal pregnancy model was established with CBA/J*BALB/C, and the RSA model was established by CBA/J*DBA/2. The RSA model CBA/J*DBA/2 pregnant mice were randomly divided into four groups (RSA model group, STW low, medium and high dose groups) according to the order of pregnancy, respectively. The drug administration starts from the first day of pregnancy to the 14th day of pregnancy. The embryo loss rate (ELR) of each group was calculated. (2) Proteomic analysis of decidual tissue: The total protein of decidual tissue of each group was isolated by solid phase pH gradient 2-DE technique. The differentially expressed protein spots were analyzed and identified by PDQuest images; the peptide quality fingerprinting (PMF) was obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Then, the proteins were identified by Mascot software searching, their functions were identified by bioinformatics strategy. (3) The expression of HSP27, α-enolase and Transferrin was detected by Western blotting and the expression of Annexin A2 and Transferrin was detected by immunohistochemistry. (4) The differential proteins and potential targets were analyzed by systematic biological strategy.

RESULTS

(1) Compared with the normal group, the ELR in the RSA model group was significantly higher (P < 0.01). Compared with the model group, the ELR in the STW high, medium dose groups was lower (P < 0.01). (2) A 2-DE map of the decidual tissue of the RSA model group, normal pregnancy group, STW low, medium and high dose groups was established. Thirty proteins were identified. (3) The results of western blot showed that the expression of HSP27 and a-enolase in the RSA model group was higher than that in the normal group, and the expression of transferrin was lower (P < 0.01). Compared with the model group, the expression of HSP27 and a-enolase in STW high, medium dose groups was decreased (P < 0.01); Compared with the model group, the expression of Transferrin in the STW high dose group was increased (P < 0.01). (5) A lot of RSA treatment-related targets, biological processes and pathways were found after the systematic biological analysis.

CONCLUSION

(1) STW may reduce the ELR of the RSA mice. (2) The results of proteomics suggest that RSA is a complex process involving multiple proteins. STW can regulate the expression of various proteins in the decidual tissue of RSA mice, suggesting that it can act on multiple targets. (3) The results of western blotting of HSP27, a-enolase, transferrin were consistent with the results of proteomic analysis. (4) STW may achieve therapeutic effects by interfering with the targets, biological processes and signaling pathways discovered in this study.

Association between rs1049174 NKG2D gene polymorphism and idiopathic recurrent spontaneous abortion in Iranian women: a case-control study

Natural killer group 2, member D (NKG2D) is one of the best known activating receptors of NK cells, which recognises its ligand on altered or stressed cells and activates NK cells to kill them. In this study, the single nucleotide polymorphism of the NKG2D gene for rs1049174 mutation was compared in 140 women with recurrent spontaneous abortion (RSA) and 175 control women with at least one successful pregnancy and without any known pregnancy loss. The findings just revealed that GG genotype and G allele were significantly higher in the case group compared with the control group (p < .001). Our results regarding decreased risk of RSA in C allele (OR = 0.438; 95%CI = 0.310-0.619; p < .001), and GC genotype (OR = 0.492; 95%CI = 0.214-0.574; p < .001) compared with G allele and GG genotype respectively. This study demonstrated a significant association between NKG2D gene polymorphism (rs1049174 G/C) and the risk of RSA in Iranian women.Impact statementWhat is already known on this subject? According to previous investigations, maternal immune responses may affect the foetus, causing recurrent spontaneous abortion (RSA). The main cause of RSA has not yet been detected in nearly 50% of the cases.What do the results of this study add? The results showed that the frequency of G allele and C allele were significantly different in the case group and control group.What are the implications of these findings for clinical practice and/or further research? The results suggest a protective function of C allele because it significantly decreased the risk of RSA compared to G allele. It improves inhibition of NK cells and probably participates in maintaining pregnancy in fertile controls; whereas, G allele is related to a slight inhibition of NK cells, probably leading to increase effectiveness of NK activation and undesirable inflammation, which consequently causes foetal rejection.

The expression of intracellular cytokines of decidual natural killer cells in unexplained recurrent pregnancy loss

OBJECTIVE

This study aims to investigate the expression levels of TNF-α, IFN-γ, IL-4, and IL-10 in dNK cells and determine whether or not the MAPK signal pathway is involved in the regulation of cytokine secretion by dNK cells at the maternal-fetal interface.

METHODS

In this study, we collected decidua specimens from patients with apparently normal pregnant and unexplained recurrent pregnancy loss (URPL) and extracted dNK cells by enzymatic digestion. Then the expression of cytokines were analyzed by flow cytometry and Real-Time PCR respectively.

RESULTS

The secretions of both IFN-γ and TNF-α in dNK cells in URPL were significantly higher than those in normal pregnancy. Furthermore, p38/MAPK inhibitors can inhibit the secretion of four cytokines in normal pregnancy, while in URPL cases, p38/MAPK inhibitors only significantly inhibit the secretion of IL-4 and IFN-γ. ERK inhibitors had no effect on the expression of all four cytokines and JNK/MAPK inhibitors varied on different cytokines.

CONCLUSION

URPL is associated with a NK1 cytokine profile. MAPK signaling pathway is involved in the regulation of cytokine secretion by decidual NK cells at maternal-fetal interface.

Association of IL-1β, IL-6, TNF-α, and TGFβ1 Gene Polymorphisms with Recurrent Spontaneous Abortion in Polycystic Ovary Syndrome

Recurrent spontaneous abortion (RSA) is a common pregnancy-associated complication of polycystic ovary syndrome (PCOS) which is an endocrine malfunction disease. Patients with PCOS may have several underlying contributing and interrelated factors, which have been reported in women with RSA. The incidence rate between PCOS and RSA remains uncertain. The aim of this study is to determine the possible association of IL-1β-511C/T, IL-6-174G/C, TNF-α-1031T/C, and TGFβ1-509T/C with RSA patients with or without PCOS. A total of 140 RSA patients, 70 of which were PCOS patients, and 140 healthy females with no history of RSA or PCOS were included in this study. PCR amplification, genotyping, and sequence analysis were employed to investigate the presence of the polymorphisms. The genotypic and allelic frequencies were calculated separately for each subject. Out of the four studied polymorphisms, the IL-1β-511C/T genotype in RSA without PCOS patients (12.7%) was significantly different compared with that in control subjects (p = 0.047). For IL-6-174C/G, there was a tendency towards more CC carriers among RSA with PCOS patients (10%) than in controls (3%). The GG genotype in RSA women with PCOS (60%) was significantly different compared with that in control subjects (p = 0.033), and the GC genotype in RSA with PCOS patients (30%) showed a marginal significant difference compared with that in control subjects (p = 0.050). Significant difference was identified in the allelic frequencies in RSA patients with PCOS compared to controls (p = 0.025). IL-6-174G/C and TNF-α-1031T/C polymorphisms are significantly associated with RSA patients in Saudi patients with PCOS, while the IL-1β-511C/T polymorphism is significantly associated with RSA patients without PCOS.

Molecular and biochemical investigations of key antioxidant/oxidant molecules in Saudi patients with recurrent miscarriage

The present study was undertaken to: i) Determine the levels of oxidative stress (OS) markers, malondialdehyde (MDA), superoxide anions (SOA) and hydrogen peroxide (H₂O₂), in both plasma and placental tissues of recurrent miscarriage (RM) patients in comparison with those of healthy pregnant (HP) and non-pregnant (NP) women; ii) determine the levels of enzymatic antioxidants [glutathione peroxidase (GPx), glutathione reductase (GSR), superoxide dismutase (SOD) and catalase (CAT)], and non-enzymatic antioxidant micronutrients [selenium (Se), zinc (Zn), copper (Cu) and manganese (Mn)] in both plasma and placental tissues of RM patients, in comparison with those of HP and NP women; iii) profile differential expression levels of selected antioxidant and apoptosis-related genes in the placental tissues of RM cases, in relation to those of HP women of matched gestational age, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results revealed highly significant increases of all investigated OS markers in plasma and placental tissues of RM patients compared with those of HP women. Moderate, but significant, increases of OS markers were observed in the plasma of HP patients in relation to those of NP women. The activities of antioxidant enzymes exhibited statistically significant decreases in both plasma and placental tissues of RM patients compared with those of HP women. The significantly reduced level of antioxidant enzymes was also evident in the plasma of HP women as compared with those of NP women. Results of RT-qPCR assays clearly indicated that the expression level of apoptosis-related genes [tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and S100A8], and pro-inflammatory cytokine genes [tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-8] were significantly upregulated in placental tissue of RM cases in relation to those of HP subjects. By contrast, mRNA transcriptional levels of key antioxidant genes (GPx, SOD, GSR and CAT) were found to be significantly reduced in placental tissue of RM patients in comparison to those of HP women. In conclusion, our data highlight a plausible cause-effect association between the observed increase in placental OS level and depletion of the activity of antioxidant enzymes. This suggests that OS is a contributing factor in the pathogenesis of idiopathic RM.

Genetics of recurrent pregnancy loss among Iranian population

Background

Recurrent pregnancy loss (RPL) is one of the most common reproductive disorders which is defined as the occurrence of recurrent miscarriage before 24 weeks of gestation and is observed among 1%–5% of women.

Methods

Various factors are associated with RPL such as immunological disorders, maternal age, obesity, alcohol, chromosomal abnormality, endocrine disorders, and uterine abnormalities. About half of the RPL cases are related with chromosomal abnormalities. Therefore, RPL genetic tests are mainly limited to karyotyping. However, there is a significant proportion of RPL cases without any chromosomal abnormalities that can be related to the single‐gene aberrations. Therefore, it is required to prepare a diagnostic panel of genetic markers besides karyotyping.

Results

In the present review, we have summarized all the significant reported genes until now which are associated with RPL among Iranian women. We categorized all the reported genes based on their cellular and molecular functions in order to determine the molecular bases of RPL in this population.

Conclusion

This review paves the way of introducing a population‐based diagnostic panel of genetic markers for the first time among Iranian RPL cases. Moreover, this review clarifies the genetic and molecular bases of RPL in this population.

Association of IL-10, IL-18, and IL-33 genetic polymorphisms with recurrent pregnancy loss risk in Iranian women

Recurrent pregnancy loss (RPL) is a heterogeneous disease with three or more consecutive abortions before 20 weeks of pregnancy. Recently, inflammatory factors such as interleukins (IL) have been found to be a significant factor in the RPL. The objective of this study was to investigate the association between RPL and IL-10 (rs1800896), IL-18 (rs1946518) and IL-33 (rs1929992) genes polymorphisms in Iranian women. The study participants consisted of 300 women with RPL and the control group comprised of 300 healthy women with successful delivery. Genomic DNA was extracted from peripheral blood, and genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). There were no significant differences in the frequencies of genotype and allele in IL-10 gene polymorphism (rs1800896) between patients and control group (p > .005). In contrast, there were significant differences in the frequencies of CC genotype in IL-18 gene polymorphism (rs1946518) between patients and the control groups (p = .004; OR =0.990; 95% CI: 0.320-8.855). Also, there were significant differences in the frequencies of GA genotype in IL-33 gene polymorphism (rs1929992) between patients and the control groups (p = .001; OR =0.955; 95% CI: 0.239-9.807). Present study showed that the rs1800896 polymorphism (IL-10) might not play role in RPL in the Iranian population; whereas rs1946518 (IL-18) and rs1929992 (IL-33) polymorphisms may be associated with the risk of RPL in the Iranian women.

Interleukin-3 Polymorphism is Associated with Miscarriage of Fresh in Vitro Fertilization Cycles

The aim of this study was to examine the association between interleukin (IL) genes polymorphisms and in vitro fertilization (IVF) outcome. A prospective cohort analysis was performed at a Women’s Hospital IVF centre of 1015 female patients undergoing fresh non-donor IVF cycles. The effects of the following six single nucleotide polymorphisms (SNPs) in five IL genes on IVF outcomes were explored: IL-1α (rs1800587 C/T), IL-3 (rs40401 C/T), IL-6 (rs1800795 C/G), IL-15 (rs3806798 A/T), IL-18 (rs187238 C/G) and IL-18 (rs1946518 G/T). The main outcome measures included clinical pregnancy, embryo implantation, abortion and live birth rates. There were no statistically significant differences in clinical pregnancy, embryo implantation and live birth rates in the analysis of 1015 patients attempting their first cycle of IVF. Infertile women with IL-3 homozygous major genotype had a higher abortion rate than those with heterozygous and homozygous minor genotype (16.5% vs. 7.9%, P = 0.025). In conclusion, our results indicated that the IL-3 rs40401 polymorphism is associated with increased risk of abortion of IVF patients. Future studies with inclusion of other ethnic populations must be conducted to confirm the findings of this study.

Distinct pattern of Th17/Treg cells in pregnant women with a history of unexplained recurrent spontaneous abortion

The aim of the current study was to determine the pattern of immune cells and related functional molecules in peripheral blood and at the maternal-fetal interface in women with unexplained recurrent spontaneous abortion (URSA). In part I, 155 women were included and divided into four groups: non-pregnant controls with no history of URSA (NPCs), pregnant controls with no history of URSA (PCs), non-pregnant women with a history of URSA (NPUs), and pregnant women with a history of URSA (PUs). Venous blood samples were collected and analyzed. In part II, 35 subjects with URSA and 40 subjects in the early stage of normal pregnancy who chose to undergo an abortion were recruited. Samples of the decidua were collected, and the proportion of immune cells and the expression of related molecules were evaluated. Peripheral regulatory T cells (Treg cells) increased in PCs compared to NPCs, but in women with URSA the flux of Treg cells disappeared when pregnancy occurred. Levels of interleukin-10 (IL-10), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and IL-17 and the ratio of Th17/Treg cells in peripheral blood remained stable among the four groups. At the maternal-fetal interface, the percentage of Treg cells, the level of CTLA-4 of CD4⁺CD25⁺CD127^lo cells and CD4⁺Foxp3⁺ cells were significantly lower in women with URSA compared to controls, respectively. Levels of transforming growth factor-β1 (TGF-β1) mRNA and protein in the decidua significantly decreased in URSA while levels of IL-6 and tumor necrosis factor-ɑ (TNF-ɑ) and the Th17/Treg ratio significantly increased. In conclusion, peripheral Treg cells did not increase in pregnant women with URSA. The decrease in Treg cells and levels of CTLA-4 and TGF-β1 and as well as the increase in levels of IL-6 and TNF-ɑ, and the Th17/Treg ratio at the maternal-fetal interface might contribute to inappropriate maternal-fetal immune tolerance in URSA.

ESHRE guideline: recurrent pregnancy loss

STUDY QUESTION

What is the recommended management of women with recurrent pregnancy loss (RPL) based on the best available evidence in the literature?

SUMMARY ANSWER

The guideline development group formulated 77 recommendations answering 18 key questions on investigations and treatments for RPL, and on how care should be organized.

WHAT IS KNOWN ALREADY

A previous guideline for the investigation and medical treatment of recurrent miscarriage was published in 2006 and is in need of an update.

STUDY DESIGN, SIZE, DURATION

The guideline was developed according to the structured methodology for development of ESHRE guidelines. After formulation of key questions by a group of experts, literature searches and assessments were performed. Papers published up to 31 March 2017 and written in English were included. Cumulative live birth rate, live birth rate and pregnancy loss rate (or miscarriage rate) were considered the critical outcomes.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Based on the collected evidence, recommendations were formulated and discussed until consensus was reached within the guideline group. A stakeholder review was organized after finalization of the draft. The final version was approved by the guideline group and the ESHRE Executive Committee.

MAIN RESULTS AND THE ROLE OF CHANCE

The guideline provides 38 recommendations on risk factors, prevention and investigations in couples with RPL, and 39 recommendations on treatments. These include 60 evidence-based recommendations – of which 31 were formulated as strong recommendations and 29 as conditional – and 17 good practice points. The evidence supporting investigations and treatment of couples with RPL is limited and of moderate quality. Of the evidence-based recommendations, only 10 (16.3%) were supported by moderate quality evidence. The remaining recommendations were supported by low (35 recommendations: 57.4%), or very low quality evidence (16 recommendations: 26.2%). There were no recommendations based on high quality evidence. Owing to the lack of evidence-based investigations and treatments in RPL care, the guideline also clearly mentions investigations and treatments that should not be used for couples with RPL.

LIMITATIONS, REASONS FOR CAUTION

Several investigations and treatments are offered to couples with RPL, but most of them are not well studied. For most of these investigations and treatments, a recommendation against the intervention or treatment was formulated based on insufficient evidence. Future studies may require these recommendations to be revised.

WIDER IMPLICATIONS OF THE FINDINGS

The guideline provides clinicians with clear advice on best practice in RPL, based on the best evidence available. In addition, a list of research recommendations is provided to stimulate further studies in RPL. One of the most important consequences of the limited evidence is the absence of evidence for a definition of RPL.

STUDY FUNDING/COMPETING INTEREST(S)

The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings, with the literature searches and with the dissemination of the guideline. The guideline group members did not receive payment. J.E. reports position funding from CARE Fertility. S.L. reports position funding from SpermComet Ltd. S.M. reports research grants, consulting and speaker’s fees from GSK, BMS/Pfizer, Sanquin, Aspen, Bayer and Daiichi Sankyo. S.Q. reports speaker’s fees from Ferring. The other authors report no conflicts of interest.

ESHRE Pages are not externally peer reviewed. This article has been approved by the Executive Committee of ESHRE.

Immunologic Abnormalities, Treatments, and Recurrent Pregnancy Loss: What Is Real and What Is Not?

Recurrent pregnancy loss, depending on the definition, affects 1% to 3% of women aiming to have a child. Little is known about the direct causes of recurrent pregnancy loss, and the condition is considered to have a multifactorial and complex pathogenesis. The aim of this review was to summarize the evaluation and the management of the condition with specific emphasis on immunologic biomarkers identified as risk factors as well as current immunologic treatment options. The review also highlights and discusses areas in need of further research.

Haplotype analysis of IL-10 gene polymorphism in couples with spontaneous abortions and aborted fetuses

Spontaneous abortion is the loss of pregnancy during an early gestational period. Interleukin-10 is an anti-inflammatory cytokine which plays an important role in successful pregnancy outcome. The aim of the study is to elucidate an association of IL-10 gene promoter polymorphisms (-1082G/A, -819 C/T, -592C/A) in spontaneous abortions from Telangana state of South India. The present population-based retrospective case-control triad study includes a total of 80 case families with spontaneous abortions and 100 control families with medically terminated pregnancies. Peripheral blood from all the couples and fetal tissues of <20 weeks of gestation were collected. Genotype analysis was carried out by a standard amplification refractory mutation system-polymerase chain reaction followed by agarose gel electrophoresis. The strength of the association between IL-10 gene promoter polymorphisms and spontaneous abortions were measured by odd ratios and their respective 95% confidence intervals. Haplotype analysis was carried out for the three polymorphisms to establish an association of specific haplotypes with spontaneous abortions. The increased frequency of AA genotype and A allele of -1082G/A, TT genotype and T allele of -819C/T, and AA genotype and A allele of -592C/A was observed in case fetuses and case mothers compared to their respective controls. Haplotype analysis revealed that A-C-A, G-C-A haplotypes in fetuses and haplotypes A-C-C, G-T-C, A-T-A, and G-C-A in mothers were associated with increased risk of spontaneous abortions. IL-10 gene promoter polymorphisms may act as a major genetic regulator in the etiology of spontaneous abortions with maternal genome imprinting effects.

Genetics of recurrent miscarriage and fetal loss

Despite years of research, miscarriage, particularly when recurrent, continues to pose a medical challenge. An embryo chromosomal error is responsible for 50-60% of recurrent cases; however, up to 30-50% remains an enigma. Successful pregnancy involves different maternal physiologic changes and certain complex interactions between the fetus and the mother by cytokines, angiogenic mediators and hormones. To date, research lines have focused on genetic and epigenetic polymorphisms related mainly to immune response and inflammatory mediators, and have yielded a significant relationship between recurrent miscarriage and immune mechanisms. Thus, unknown causes of miscarriage could be due to an immune imbalance induced by T-helper Th1/Th2/Th17 cytokines and regulatory T cells. Furthermore, these genes and mediators have long been suspected of being blood markers for the clinical diagnosis and management of miscarriage; however, more evidence is required for them to be included in medical practice and obstetric guidelines.

No Association between TNF-α -308G/A Polymorphism and Idiopathic Recurrent Miscarriage: A Systematic Review with Meta-Analysis and Trial Sequential Analysis

Background

Conflicting results were reported on the association between the TNF-α -308G/A polymorphism and idiopathic recurrent miscarriage (IRM). Though three meta-analyses have been conducted on this topic, the conclusions were contradictory, and the results may be unreliable as certain crucial conditions were neglected.

Method

A complete search was conducted in PubMed, Cochrane Library, and Embase, other sources like Google Scholar, ClinicalTrial.gov and reference lists of relevant articles were also retrieved. All candidate articles were accessed and screened using specific inclusion and exclusion criteria. Statistical analyses were performed on data extracted from eligible studies using the STATA 12.0 software and the TSA 0.9 beta software.

Results

Eventually, 12 case-control studies from 11 publications (with 1,807 cases and 2,012 controls) were included in this meta-analysis, and no evidence of any significant association was found in the overall analyses between the TNF-α -308G/A polymorphism and IRM risk. However, significant association was shown in Asian population (four studies from three publications) in the dominant model (AA + GA vs. GG), the allelic model (A vs. G), and the heterozygote model (GA vs. GG).

Conclusions

TNF-α -308G/A polymorphism is not associated with IRM risk. Though significant association was found in Asian population, the result needs further confirmation from more studies.

Differences in Cytokine Expression and STAT3 Activation between Healthy Controls and Patients of Unexplained Recurrent Spontaneous Abortion (URSA) during Early Pregnancy

Unexplained recurrent spontaneous abortion (URSA) is a common complication of pregnancy. Although tolerance of the maternal immune system is considered to be essential for a normal pregnancy, the precise mechanism underlying the pathogenesis of URSA remains to be fully elucidated, albeit it is known to involve inflammation. Here, we examine the relationship between the expression of inflammatory cytokines and the activation of downstream signaling pathways in URSA patients. Decidual and peripheral blood samples were collected from 30 URSA patients and from 30 women with normal early pregnancies. Western blot analysis was used to measure the expression levels of signal transducers and activators of transcription 3(STAT3), phosphorylated STAT3(p-STAT3), and interleukin-17 receptor(IL-17R) in the decidual samples. Enzyme-linked immunosorbent assay was used to assess the levels of IL-17, IL-10, IL-6, and IL-23 in the peripheral blood and decidual samples. In the URSA patients, the IL-10 expression levels were lower than those in the control subjects (P<0.05), whereas IL-6, IL-17, and IL-23 were all expressed at higher levels(P<0.05). Furthermore, the expression levels of IL-17R and p-STAT3 were higher in the URSA patients, exhibiting a trend similar to that of IL-23. Our finding of increased IL-23 expression in the deciduae and peripheral blood of patients with URSA suggest that this maybe a contributing factor to the pathogenesis of this disease. Likewise, STAT3 activation through its phosphorylation, which was associated with the IL-23 increase, may also be involved in URSA pathogenesis. However, the precise pathogenic mechanism requires further study.

Immunogenetic contributions to recurrent pregnancy loss

While sporadic pregnancy loss is common, occurring in 15 % of pregnancies, recurrent pregnancy loss (RPL) impacts approximately 5 % of couples. Though multiple causes are known (including structural, hormonal, infectious, autoimmune, and thrombophilic causes), after evaluation, roughly half of all cases remain unexplained. The idiopathic RPL cases pose a challenging therapeutic dilemma in addition to incurring much physical and emotional morbidity. Immunogenetic causes have been postulated to contribute to these cases of RPL. Natural Killer cell, T cell expression pattern changes in the endometrium have both been shown in patients with RPL. Human leukocyte antigen (HLA) and cytokine allelic variations have also been studied as etiologies for RPL. Some of the results have been promising, however the studies are small and have not yet put forth outcomes that would change our current diagnosis and management of RPL. Larger database studies are needed with stricter control criteria before reasonable conclusions can be drawn.

Genetic variant in IL-33 is associated with idiopathic recurrent miscarriage in Chinese Han population

Recurrent miscarriage (RM) is the occurrence of repeated pregnancies that end in miscarriage of the fetus before 20 weeks of gestation. At least 50% of the RM patients are considered idiopathic. High IL-33 levels are critical in early pregnancy and impact the outcome of subsequent pregnancies. However, the association of polymorphisms of IL-33 with idiopathic RM is still unclear. The present study was initiated to investigate whether IL-33 polymorphisms are risk factors for idiopathic RM in Chinese Han population. Study subjects comprised of 321 cases and 384 controls. Five polymorphisms (rs10435816, rs16924159, rs16924171, rs1929992, rs1332290) in IL-33 and serum IL-33 concentrations were assessed. rs16924159 variant exhibits significant association with RM in additive and recessive genetic model (additive model P = 0.015, recessive model P = 0.007). In contrast, rs10435816, rs16924171, rs1929992 and rs1332290 are not significantly associated with RM. Serum IL-33 levels are significantly lower in RM cases than in control (173.51 ± 94.12 versus. 200.97 ± 110.06 (pg/ml), P = 4.57 × 10⁻⁴). There are lower levels of serum IL-33 in rs16924159 homozygous mutant (AA) than homozygous wild-type (GG) in this study population, including cases and control groups (172.18 ± 103.01 versus. 205.82 ± 119.01 (pg/ml), P = 0.006). Reduced IL-33 levels and rs16924159 IL-33 variant may contribute to the pathogenesis of idiopathic RM in Chinese Han population.

Association between IL-6 -174 G/C, IL-6 -634 G/C, and IFN-γ +874 A/T polymorphisms and susceptibility to recurrent pregnancy loss: a meta-analysis

OBJECTIVE

The aim of this study was to determine whether interleukin-6 (IL-6) -174 G/C, IL-6 -634 G/C, and interferon-γ (IFN-γ) +874 A/T polymorphisms are associated with susceptibility to recurrent pregnancy loss (RPL).

METHODS

We conducted a literature search using PubMed and EMBASE databases and performed a meta-analysis using fixed- or random-effects models.

RESULTS

A total of 15 articles met the study inclusion criteria. When all study subjects were considered together, meta-analysis showed no association between RPL and the IL-6 -174 GG + GC genotype (odds ratio [OR] = 0.794, 95 % confidence interval [CI] = 0.542-1.163, p = 0.236). However, stratification of the data by ethnicity indicated an association between this genotype and RPL in non-Caucasians (OR = 0.528, 95 % CI = 0.302-0.925, p = 0.028), but not in Caucasian populations. Moreover, meta-analysis revealed an association between RPL and the IL-6 -634 GG + GC genotype in all study subjects (OR = 0.556, 95 % CI = 0.383-0.806, p = 0.002), while stratification by ethnicity revealed a negative association between this genotype and RPL in Asian (OR = 0.545, 95 % CI = 0.371-0.800, p = 0.002) but not Middle Eastern populations. Furthermore, a relationship between the IFN-γ +874 A allele and RPL was identified in non-Caucasians (OR = 1.403, 95 % CI = 1.133-1.734, p = 0.002), but not in Caucasians.

CONCLUSIONS

This meta-analysis demonstrates that IL-6 -174 G/C, IL-6 -634 G/C, and IFN-γ +874 A/T polymorphisms are associated with susceptibility to RPL, particularly in non-Caucasians.

A functional polymorphism in the promoter region of interleukin-10 gene increases the risk for spontaneous abortions--a triad study

PURPOSE

Spontaneous abortion or miscarriage is the natural death of an embryo or foetus in the early stages of prenatal development. Interleukin-10 is an anti-inflammatory cytokine, produced by human cytotrophoblasts, and defects in its production result in specific pathological conditions during pregnancy. The present study is aimed to evaluate the association of IL-10 -1082G/A polymorphism in spontaneous abortions by comparing foetal, maternal and paternal groups--a triad study.

METHODS

A total of 50 families with spontaneous abortions and 60 families with medically terminated pregnancies were considered for the present study. DNA from foetal tissue and parental blood samples were extracted, and the genotype analysis of IL-10 -1082G/A promoter polymorphism was carried out by amplification refractory mutation system-polymerase chain reaction followed by agarose gel electrophoresis. A statistical analysis was applied to test for the significance of the results.

RESULTS

There was a statistically significant difference in the distribution of AA genotypes and A allele of IL-10 -1082G/A between the two family groups among foetuses (P = 0.0002) and mothers (P = 0.00005). The paternal group showed no significant difference in the genotype distribution of IL-10 between cases and controls.

CONCLUSION

In conclusion, IL-10 G-1082A gene promoter polymorphism may act as a major genetic regulator in the etiology of spontaneous abortions.

Association of interleukin 1 receptor antagonist (IL1RN) gene polymorphism with recurrent pregnancy loss risk in the North Indian Population and a meta-analysis

An appropriate ratio of interleukin 1 beta to interleukin 1 receptor antagonist (IL1Ra) is required for successful pregnancy. Our objective was to study the genetic association between IL1RN variable numbers of tandem repeat (VNTR) polymorphism and recurrent pregnancy loss (RPL). To analyze the association between IL1RN VNTR allele and RPL, we investigated the IL1RN VNTR polymorphism in 136 RPL patients and in 200 healthy control women. Meta-analysis on this polymorphism was conducted to support our findings. PCR based approach was used to analyze IL1RN VNTR polymorphism and it was further confirmed by sequencing. Systematic review and meta-analysis was done using electronic database (Pub-Med, Google Scholar and Ovid) up to February 27, 2013. This meta-analysis was assessed by comprehensive meta-analysis software version 2. For meta-analysis 549 cases and 1,450 controls were included. The frequency of IL1RN genotype 2/2 was significantly higher in RPL compared to control group (AORs 3.10, 95 % CI 1.58-6.11, p = 0.001). The presence of rare allele also increased the risk of RPL significantly (ORs 1.63, 95 % CI 1.16-2.29, p = 0.004). The meta-analysis stratified by ethnicity showed that individuals with allele 2 had increased risk of RPL (OR 1.29, 95 % CI 1.04-1.61, p = 0.01), in Asians population by using fixed model. However the data of the present study clearly suggests that IL1RN VNTR polymorphism is a genetic risk factor for pregnancy loss in the study population.

A genetic association study of NLRP2 and NLRP7 genes in idiopathic recurrent miscarriage

STUDY QUESTION

Do gene polymorphisms of two members of the human innate immune sensor nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing proteins (NLRP) family, NLRP2 and NLRP7, confer susceptibility to idiopathic recurrent miscarriage (RM)?

SUMMARY ANSWER

We found a significant association of a tag single-nucleotide polymorphism (SNP) of NLRP7 (rs26949) with idiopathic RM, while a tag SNP of NLRP2 (rs127868) showed a marginally significant association.

WHAT IS KNOWN ALREADY

Human NLRP2 and NLRP7 have been suggested to be maternal effect genes, regulating early embryonic development and establishment of maternal imprints. Anecdotal evidence showed women who had experienced at least three consecutive miscarriages without hydatidiform mole carried non-synonymous NLRP7 variants. Whether these two genes are associated with idiopathic RM remains obscure.

STUDY DESIGN, SIZE AND DURATION

In this case-controlled study, 143 women who had experienced at least two consecutive spontaneous miscarriages (n = 91 women with two miscarriages, n = 52 with three or more) and 149 controls were included between 2004 and 2010.

MATERIALS, SETTING, METHODS

A total of five tag SNPs of NLRP2 and eight tag SNPs of NLRP7 were genotyped using the primer extension analysis. The deviation from the Hardy-Weinberg equilibrium was checked using χ(2) analysis. The logistic odds ratios (ORs) of RM were estimated with a 95% confidence interval (CI) in multivariate analysis after maternal age adjustment. The false discovery rate (FDR) was used to adjust for multiple testing. Tests for haplotype association with RM were performed. Gene-gene interactions among loci of the two genes were evaluated by using the multifactor dimensionality reduction (MDR) method.

MAIN RESULTS AND THE ROLE OF CHANCE

One tag SNP rs269949 of NLRP7 showed significant difference between patients and controls in a recessive model (FDR P = 0.0456, age-adjusted OR (AOR) = 16.49, 95% CI = 2.00-136.11 for the GG genotype). The difference was significant in patients with two consecutive miscarriages and also in those with three or more consecutive miscarriages. Meanwhile, one tag SNP of NLRP2 (rs12768) showed marginal significance between patients and controls in a co-dominant model (FDR P = 0.0505, AOR = 2.15, 95% CI = 1.29-3.58 for the AC genotype). In the haplotype analysis, NLRP2 and NLRP7 did not show any significant difference between the patients and controls. MDR test revealed that there is no significant gene-gene interaction among loci of NLRP2 and NLRP7.

LIMITATIONS, REASONS FOR CAUTION

The results may be biased by heterogeneous ethnicities of the Taiwanese Han and a small sample size. The genetic loci responsible for the disease as well as their functional significance also await further investigation.

WIDER IMPLICATIONS OF THE FINDINGS

Our study suggests the role of the NLRP family proteins in RM.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by grants from the National Science Council of the Republic of China (NSC-100-2314-B-006-011-MY3). None of the authors have any conflicts of interest.

Global alteration in gene expression profiles of deciduas from women with idiopathic recurrent pregnancy loss

Recurrent pregnancy loss (RPL) occurs in ∼5% of women. However, the etiology is still poorly understood. Defects in decidualization of the endometrium during early pregnancy contribute to several pregnancy complications, such as pre-eclampsia and intrauterine growth restriction (IUGR), and are believed to be important in the pathogenesis of idiopathic RPL. We performed microarray analysis to identify gene expression alterations in the deciduas of idiopathic RPL patients. Control patients had one antecedent term delivery, but were undergoing dilation and curettage for current aneuploid miscarriage. Gene expression differences were evaluated using both pathway and gene ontology (GO) analysis. Selected genes were validated using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). A total of 155 genes were found to be significantly dysregulated in the deciduas of RPL patients (>2-fold change, P < 0.05), with 22 genes up-regulated and 133 genes down-regulated. GO analysis linked a large percentage of genes to discrete biological functions, including immune response (23%), cell signaling (18%) and cell invasion (17.1%), and pathway analysis revealed consistent changes in both the interleukin 1 (IL-1) and IL-8 pathways. All genes in the IL-8 pathway were up-regulated while genes in the IL-1 pathway were down-regulated. Although both pathways can promote inflammation, IL-1 pathway activity is important for normal implantation. Additionally, genes known to be critical for degradation of the extracellular matrix, including matrix metalloproteinase 26 and serine peptidase inhibitor Kazal-type 1, were also highly up-regulated. In this first microarray approach to decidual gene expression in RPL patients, our data suggest that dysregulation of genes associated with cell invasion and immunity may contribute significantly to idiopathic recurrent miscarriage.

Genetics of recurrent miscarriage: challenges, current knowledge, future directions

Recurrent miscarriage (RM) occurs in 1-3% of couples aiming at childbirth. Due to multifactorial etiology the clinical diagnosis of RM varies. The design of genetic/"omics" studies to identify genes and biological mechanisms involved in pathogenesis of RM has challenges as there are several options in defining the study subjects (female patient and/or couple with miscarriages, fetus/placenta) and controls. An ideal study would attempt a trio-design focusing on both partners as well as pregnancies of the couple. Application of genetic association studies focusing on pre-selected candidate genes with potential pathological effect in RM show limitations. Polymorphisms in ∼100 genes have been investigated and association with RM is often inconclusive or negative. Also, implication of prognostic molecular diagnostic tests in clinical practice exhibits uncertainties. Future directions in investigating biomolecular risk factors for RM rely on integrating alternative approaches (SNPs, copy number variations, gene/protein expression, epigenetic regulation) in studies of single genes as well as whole-genome analysis. This would be enhanced by collaborative network between research centers and RM clinics.

Inflammatory mediator gene polymorphisms and gestational diabetes: a review of the literature

The incidence of gestational diabetes (GD) is rising worldwide, in parallel with obesity and type 2 diabetes. Obesity and GD are conditions that have in common a state of chronic, low-grade subclinical inflammation characterized by abnormal production of cytokines and mediators. Genetic polymorphisms may influence the production of inflammatory mediators and predispose to different disorders, including diabetes. The aim of this study was to review the existing literature on the relationship between inflammatory mediator gene polymorphisms and GD. The search in PubMed was restricted to articles published in English, from January 1990 to December 2010. Eight studies were included. These publications evaluated 13 different SNPs and six inflammatory mediators in the blood of women with GD. Gene polymorphisms related to leptin, mannose-binding lectin (MBL) and RAGE (receptor for advanced glycation end products) were individually evaluated in a single study each. Leptin and MBL plasma levels were also evaluated in two studies. The participants included in the studies were ethnically different, but matched with controls. Different criteria were adopted to select the participants. Seven of the eight studies included took into consideration the BMI of patients and controls. Due to the heterogeneity and limited number of studies on GD and inflammatory gene polymorphisms, we could not pool together any of the results or perform any additional analyses of the existing data. Since the existing findings come from isolated studies with mostly small sample sizes, there is a need for new, larger, properly designed studies of good methodological quality.

Profile of inflammatory mediators in gestational diabetes mellitus: phenotype and genotype

PROBLEM

Our study aimed to assess in vitro production of IL-10, IL-6, TNF-A, and adiponectin serum levels in pregnant women with and without gestational diabetes mellitus (GDM) and to investigate a possible association between GDM and IL-10-1082 A>G (rs1800896), IL-6-174 G>C (rs1800795), TNF-A-308 G>A (rs1800629), adiponectin +45 T>G (rs2241766), and adiponectin-11377 C>G (rs266729) gene polymorphisms.

METHOD OF STUDY

This case-control study included 79 women with GDM and 169 healthy controls (C) grouped according to pre-pregnancy BMI. IL-10, IL-6, and TNF-A culture supernatant and adiponectin serum levels were assessed by ELISA. DNA genotype was performed by PCR-RFLP.

RESULTS

Adiponectin levels were significantly higher in C than GDM women, even within the same BMI category. Cytokines levels were similar between the groups. There were no associations between GDM and the analyzed gene polymorphisms.

CONCLUSIONS

Women with GDM have significantly lower adiponectin levels in the third trimester, regardless of BMI.

Association of IL-1β and IL-6 gene polymorphisms with recurrent spontaneous abortion in a Chinese Han population

As certain cytokines may play a role in unexplained recurrent spontaneous abortion (RSA) and also some cytokine gene polymorphisms may affect the level of cytokine production, the aim of this study was to investigate the relationship between Chinese RSA and polymorphisms of the genes coding for interleukin (IL)-1β (-31C/T, -511C/T, +3954C/T) and IL-6 (-634C/G). Women (n = 162) with at least three consecutive spontaneous abortions and 156 ethnically matched healthy women with at least one successful pregnancy were included. Genotypes were determined using restriction fragment length polymorphism analysis of polymerase chain reaction products. No significant differences were found in the IL-1β-31T, -511T and +3954T distributions between the RSA group and the control group. On the other hand, the frequencies of the IL-6-634GG genotype and -634G allele were significantly decreased in the RSA group versus the control group (genotype: P = 0.0003; allele: P = 0.002), suggesting the IL-6-634C/G polymorphism might be a possible genetic protective factor for RSA.

Polymorphisms in VEGF, progesterone receptor and IL-1 receptor genes in women with recurrent spontaneous abortion

Hormonal, inflammatory and vascular alterations during pregnancy are thought to be involved in pregnancy loss. The role of progesterone, the actions of which involve cytokines and vascular endothelial growth factor (VEGF), has been thoroughly studied. Genetic factors are involved in modulation of these molecules, and several genes have been associated with recurrent spontaneous abortion (RSA), as well other obstetric conditions. Here we investigate the relationship between RSA and gene polymorphisms of the progesterone receptor (PROGINS), interleukin-1 receptor 1 (PstI) and vascular endothelial growth factor (VEGF) (-634, 936). This case-controlled study comprised a total of 89 women with idiopathic RSA and a control group of 191 women with at least two successful pregnancies and no miscarriages. Genomic DNA was extracted from whole blood, and polymorphism genotyping was conducted by digesting PCR products with specific restriction endonucleases. No correlations were found in any of the investigated polymorphisms, even among dominant, co-dominant and additive inheritance models and alleles. Our results support the hypothesis that these specific gene polymorphisms are not the major determinant of pregnancy success. Although we did not find any correlations, the investigation of these and other polymorphisms remains a challenge in the evaluation of RSA.

Examination of genetic polymorphisms in newborns for signatures of sex-specific prenatal selection

Success rate in human pregnancies is believed to be very low and sex-specific mechanisms may operate in prenatal loss. Assuming a sex-differential in prenatal loss exists, we examined genetic markers in biologically plausible targets in the HLA complex, other immune system-related and iron-regulatory genes in 388 healthy newborns from Wales (UK) using one sex as a control group for the other. Genotyping of 333 single nucleotide polymorphisms (SNPs) from 107 genes was achieved mainly by TaqMan assays. Twenty-two of autosomal SNPs showed frequency differences between 187 male and 201 female newborns either individually or as part of a haplotype. Of these, six markers (RXRB rs2076310, HLA complex haplotype HLA-DQA1 rs1142316-HLA-DRA rs7192-HSPA1B rs1061581, HIST1H1T rs198844, IFNG rs2069727, NKG2D rs10772266 and IRF4 heterozygosity) showed statistically robust differences between male and female newborns and multivariable modeling confirmed their independence. There were fewer males homozygote for combined wildtype genotypes of LIF rs929271, TP53 rs1042522 and MDM2 rs2279744 compared with females [OR = 0.3, 95% confidence interval (CI) = 0.1-0.8; P < 0.01] although these SNPs did not show any association individually. It is unlikely that SNPs have clinical utility as single markers in any trait with complex etiology but polygenic predictive models remain a possibility. If their validity is confirmed in larger studies of different populations and functional mechanisms of these preliminary associations are elucidated, these markers from the HLA complex, NKG2D region and cytokines may cumulatively have sufficient predictive value for susceptibility to prenatal selection in each sex.

Maternal plasma concentration of the pro-inflammatory adipokine pre-B-cell-enhancing factor (PBEF)/visfatin is elevated in pregnant patients with acute pyelonephritis

PROBLEM

Visfatin/pre-B-cell-enhancing factor (PBEF) has been implicated in the regulation of the innate immune system, as well as in glucose metabolism. Specifically, visfatin plays a requisite role in delayed neutrophil apoptosis in patients with sepsis. The aim of this study was to determine whether pyelonephritis during pregnancy is associated with changes in maternal plasma visfatin concentration in normal weight and overweight/obese patients.

METHOD OF STUDY

This cross-sectional study included the following groups: (1) normal pregnant women (n = 200) and (2) pregnant women with pyelonephritis (n = 40). Maternal plasma visfatin concentrations were determined by ELISA. Non-parametric statistics was used for analyses.

RESULTS

(1) The median maternal plasma visfatin concentration was significantly higher in patients with pyelonephritis than in those with a normal pregnancy; (2) among overweight/obese pregnant women, those with pyelonephritis had a significantly higher median plasma visfatin concentration than women with a normal pregnancy; and (3) pyelonephritis was independently associated with higher maternal plasma visfatin concentrations after adjustment for maternal age, pre-gestational body mass index, smoking status, gestational age at sampling, and birthweight.

CONCLUSION

Acute pyelonephritis during pregnancy is associated with a high circulating maternal visfatin concentration. These findings suggest that visfatin/PBEF may play a role in the regulation of the complex and dynamic crosstalk between inflammation and metabolism during pregnancy.