The physiologic anticoagulant and anti-inflammatory role of heparins and their utility in the prevention of pregnancy complications

Cuyun Recipe ameliorates pregnancy loss by regulating macrophage polarization and hypercoagulable state during the peri-implantation period in an ovarian hyperstimulation mouse model

BACKGROUND

The Chinese herbal prescription Cuyun Recipe (CYR) has been widely used to treat clinical infertility and has shown good efficacy. Animal experiments have shown that CYR can promote implantation in mice, however, the exact mechanism underlying the implantation has not been elucidated.

PURPOSE

To investigate the effect and mechanism of CYR on regulating macrophage polarization and hypercoagulability during the peri-implantation period in mice with ovarian hyperstimulation.

METHODS

An ovarian hyperstimulation mouse model was developed, followed by treatment with CYR. Mice were sacrificed on day (D)4.5, D6, or D8 of gestation. The number of implantation sites, the pathological changes of the uterus and ovaries were assessed. The polarization of monocytes/macrophages in the spleen and endometrium, the expression and localization of cytokines were further detected. Furthermore, analyses of hypercoagulable state of the blood were also performed.

RESULTS

Treatment with CYR increased the average number of implantation sites, promoted angiogenesis in endometrial, and regulated monocytes/macrophages and the cytokine levels. Moreover, CYR downregulated the overexpression of D-dimer and fgl2 after ovarian hyperstimulation.

CONCLUSION

CYR facilitates embryo implantation by alleviating ovarian hyperstimulation, promoting endometrial decidualization and angiogenesis, regulating macrophage polarization, and reversing the hypercoagulable state of the blood.

Low-molecular-weight heparin in addition to low-dose aspirin for preventing preeclampsia and its complications: A systematic review and meta-analysis

Background

In this systematic review, we aimed to investigate the efficacy and safety of adding low-molecular-weight heparin (LMWH) or unfractionated heparin to low-dose aspirin (LDA) started ≤16 weeks'gestation in the prevention of preeclampsia (PE) in high-risk women.

Methods

PubMed, Cochrane Library, Embase, and ClinicalTrials.gov databases were searched from their inception to April 2022 for randomized controlled trials (RCTs) that to determine whether the combined treatment of LMWH and LDA is better than single anticoagulant drugs in preventing PE and improving live birth rate of fetus in high-risk women with pregnancy ≤16 weeks. We also searched Embase, OVID MEDLINE and OVID MEDLINE in-process using the OVID platform.

Results

14 RCTs involving 1,966 women were found. The LMWH (or unfractionated heparin) and LDA groups included 1,165 wemen, and the LDA group included 960 women. The meta-analysis showed that the addition of LMWH to LDA reduced the risk of PE (RR: 0.59, 95% CI: 0.44-0.79, P < 0.05), small-for-gestational age (SGA, RR: 0.71, 95% CI: 0.52-0.97, P = 0.03), fetal and neonatal death (RR: 0.45, 95% CI: 0.23-0.88, P = 0.02) and gestational hypertension (RR: 0.47, 95% CI: 0.25-0.90, P = 0.02). It is worth emphasizing that LMWH (or unfractionated heparin) combined with LDA did not increase the risk of bleeding.

Conclusions

LMWH combined with LDA can effectively improve the pregnancy outcome of women with high risk factors for PE and its complications. Although this study showed that combined medication also did not increase the risk of bleeding, but such results lack the support of large sample size studies. The clinical safety analysis of LMWH combined with LDA in patients with PE should be more carried out.

Correlation Between the Presence of Antinuclear Antibodies and Recurrent Pregnancy Loss: A Mini Review

In the past decade, the incidence of recurrent pregnancy loss (RPL) has increased significantly, and immunological disorders have been considered as one of the possible causes contributing to RPL. The presence of antinuclear antibodies (ANAs) is regarded as a typical antibody of autoimmunity. However, the relationship between the presence of ANAs and RPL, the underlying mechanism, and the possible role of immunotherapy is still controversial. The aim of this mini review is to assess the association between ANAs and RPL and the effects of immunotherapy on pregnancy outcomes in women with positive ANAs and a history of RPL from the available data and to provide a relevant reference basis for clinical application in this group of women.

Aspirin, low molecular weight heparin, or both in preventing pregnancy complications in women with recurrent pregnancy loss and factor V Leiden mutation

Objective: The aim of this study was to compare the effects of low molecular weight heparin (LMWH), LMWH plus low dose aspirin, or low dose aspirin only on pregnancy outcomes in recurrent pregnancy loss (RPL) patients with factor V Leiden mutation (FVLM).Materials and methods: A total of 2764 RPL patients were evaluated in for the etiology of RPL. Mutations in factor V Leiden homozygous and heterozygous were determined. Subsequently, 196 of these patients were diagnosed with FVLM and included in the study; of these 174 completed the study. At the sixth week of gestation of subsequent pregnancy participants were randomly distributed into three groups. Group A (n = 61) was composed of patients with an oral dose of 100 mg aspirin daily, Group B (n = 59) consisted of patients using 40 mg enoxaparin and 100 mg orally aspirin daily, and Group C (n = 54) included patients using 40 mg enoxaparin daily during pregnancy.Results: Among the 174 patients who completed the study, the live birth and miscarriage rates were similar for the three groups (p = .843 and p = .694, respectively). There was no significant difference among the groups in rates of eclampsia, placental abruption, intrauterine fetal growth restriction and gestational diabetes mellitus. The number of preeclamptic patients was significantly higher in Group A than Groups B and C. The levels of preterm birth was significantly higher in Group A than Groups B and C.Conclusion: Using low dose aspirin, LMWH plus aspirin, or LMWH alone yielded comparable live birth rates in RPL patients with FVLM. However, LMWH decreased the risk of preeclampsia in this group of patients. LMWH might therefore have a preventive role regarding preeclampsia.

The role of epigenetic changes in preeclampsia

Preeclampsia (PE) is a disorder affecting 2-10% of pregnancies and has a major role for perinatal and maternal mortality and morbidity. PE can be occurred by initiation of new hypertension combined with proteinuria after 20 weeks gestation, as well as various reasons such as inflammatory cytokines, poor trophoblast invasion can be related with PE disease. Environmental factors can cause epigenetic changes including DNA methylation, microRNAs (miRNAs), and histone modification that may be related to different diseases such as PE. Abnormal DNA methylation during placentation is the most important epigenetic factor correlated with PE. Moreover, changes in histone modification like acetylation and also the effect of overregulation or low regulation of miRNAs or long noncoding RNAs on variety signaling pathways can be resulted in PE. The aim of this review is to describe of studies about epigenetic changes in PE and its therapeutic strategies.

Hemostasis-related gene polymorphisms and their epistatic relationship in women with idiopathic infertility

: A numerous factor can cause infertility, but around one of four reproductive failure cases remain unexplained and diagnosed as idiopathic infertility. In the past few decades, analysis of gene polymorphisms takes a significant place in pathogenesis of infertility. The aim of this study was to evaluate the possible role of hemostasis-related gene polymorphisms in unexplained infertility. The study includes 117 female patients with idiopathic infertility and 130 fertile women with at least one born child. Eight polymorphisms important for hemostasis (ITGB3 1565T>C, FV 1691G>A, FII 20210G>A, MTHFR 677C>T and 1298A>C, ATIII 786G>A, PAI-14G/5G and ACE I/D) were genotyped by real-time PCR system. The frequencies of alleles and genotypes of examined polymorphisms were analyzed in SPSS statistical program, whereas gene interactions were identified using the GMDR software. Examination of etiological factors has shown that family history is a significant factor in assessing individual risk for infertility. The alleles and genotypes frequency of FV 1691G>A and FII 20210G>A polymorphisms were statistically different between control and patient group leading to a greater risk for infertility. The analysis of epistatic relationship between examined hemostasis-related gene polymorphisms identified more complex high-risk genotypes associated with infertility. Our results suggest that positive family history could be important predictive factor for fertility problems, pointing to the potential hereditary basis of this condition. Polymorphisms FVL and FII prothrombin are independent risk factors for idiopathic infertility, whereas multilocus interactions approach should be taken into consideration for the future research.

Clinical utility of thrombophilia, anticoagulant treatment, and maternal variables as predictors of placenta-mediated pregnancy complications: an extensive analysis

Objective: The objective of this study is to analyze the usefulness of thrombophilia and antithrombotic drugs in combination with materno-fetal characteristics to generate a predictive model of placenta-mediated pregnancy complications (PMPC) for counseling treatment.Methods: A retrospective analysis was performed in women with singleton pregnancy that required a thrombophilia study, including 222 patients with unknown cause PMPC and 151 women with no complications at current pregnancy in Hospital Clínico Universitario, Lozano, Blesa, Zaragoza, Spain. Chi-squared and Mann-Whitney test were applied to analyze univariate risk factors. Multivariate analysis was performed using logistic regression model with candidate variables: maternal characteristics, obstetric history, thrombophilia, and treatment with low-molecular-weight heparin (LMWH) and/or with acid acetylsalicylic (ASA). The calibration, discrimination, and best cutoff point for the clinical application of the model was analyzed.Results: Maternal characteristics showed differences in median body mass index (BMI), odds ratio (OR): 0.4, smoking habit, OR: 8.5, and hypertension, OR: 11.4, appearing all of them as risk factors. In our study, a prior pregnancy that ended in a child alive was a protective factor OR: 0.02-0.4, and having a previous preterm child was a strong risk factor OR: 4.2. Thrombophilia was not a risk factor. Patients under LMWH treatment (15%) and/or ASA (6.2%) had better pregnancy outcomes, showing both as protective factors: ASA OR: 0.32 and LMWH OR: 0.16. The model has an AUC value of 0.847, with good calibration. A nomogram and an app is provided for this adjusted model with high discrimination ability in internal validation (AUC = 0.833). Our clinical utility analysis guide us to choose 40% as the best threshold probability.Conclusions: We found risk and protective factors associated with PMPC, but our data were not conclusive to demonstrate its relation with maternal thrombophilia. However, the challenger finding is the clinical utility of antithrombotic drugs as a protective factors in PMPC prevention. It is possible to identify patients with high risk of PMPC through a combined predictive model, for counseling treatment.

Delayed hemolysis, elevated liver enzymes, low platelet count syndrome in succession of switches of preventive anticoagulant treatment in a 41-year-old patient with a history of recurrent assisted implantation failures: a case report

Background

For the past decades the mean age of primiparae in Western societies is constantly increasing. At the same time, there is a growing demand for assisted reproductive technologies such as in vitro fertilization and intracytoplasmic sperm injection. Subsequently, a higher prevalence of pregnancy-associated diseases such as gestational hypertension and preeclampsia is observed. To improve pregnancy rates after in vitro fertilization/intracytoplasmic sperm injection and to reduce the risk of pregnancy-associated diseases with a cardiovascular pathophysiology, two anticoagulants are the focus of current research: low molecular weight heparin and acetylsalicylic acid (aspirin).

Case presentation

A 41-year-old white woman, gravida 3, para 0, received low molecular weight heparin to reduce the risk of abortion after five unsuccessful intracytoplasmic sperm injections and two miscarriages. She autonomously discontinued the medication with low molecular weight heparin at 12 weeks and 2 days of gestation and took aspirin instead until 24 weeks and 2 days of gestation as preeclampsia prophylaxis. However, the pregnancy ended with an urgent cesarean section at 27 weeks and 4 days of gestation due to a fast progressing hemolysis, elevated liver enzyme levels, and low blood platelet count syndrome, a potentially life-threatening variant of preeclampsia.

Conclusion

Based on the current demographic trend toward late-in-life pregnancy it is mandatory to establish clear guidelines concerning preventive treatment options of preeclampsia for patients with risk factors. The establishment of a special first-trimester screening for these women should be discussed. Moreover, it is necessary to raise the awareness among physicians of these contemporary issues to guarantee the best possible medical care.

Electronic supplementary material

The online version of this article (10.1186/s13256-018-1943-1) contains supplementary material, which is available to authorized users.

Bemiparin as a Prophylaxis After an Unexplained Stillbirth: Open-Label Interventional Prospective Study

Stillbirth is a devastating event to the parents, relatives, friends, and families. The role of anticoagulants in the prevention of unexplained stillbirths is uncertain. An open-label interventional prospective cohort study was conducted on 144 women with a history of unexplained stillbirths. The intervention group had a high umbilical artery resistance index (RI) and received bemiparin. The nonintervention group had a normal RI and did not receive any intervention. We measured the adjusted odds ratio (OR) and 95% confidence interval (CI) of the main outcome for these variables using logistic regression analysis. Fresh stillbirth and early neonatal death rates were lower (P = .005, OR = 11.949 and 95% CI = 2.099-68.014) and newborn weight was higher (P = .015, OR = 0.048, 95% CI = 0.004-0.549) in the group that received bemiparin. Bemiparin is effective in decreasing the rate of stillbirth in women with a history of previous unexplained stillbirths.

Prevention of preeclampsia in high-risk patients with low-molecular-weight heparin: a meta-analysis

Objective: To assess the secondary preventive effect of low-molecular-weight heparin (LMWH) on pregnant women with prior early-onset or severe preeclampsia (PE).Methods: A systematic literature search of several databases was conducted for randomized controlled trials comparing LMWH with either aspirin or no treatment in pregnant women at a high risk of placental-mediated pregnancy complications (PMPCs). Odds ratios and associated 95% confidence intervals (CI) and weighted mean differences and 95% CI were calculated.Results: Seven studies including 1035 patients were evaluated. These studies showed a risk reduction in composite PMPC outcome (relative risk (RR) 0.635 (95% CI: 0.436-0.925); p=.018), PE (RR 0.522 (95% CI: 0.334-0.815); p=.004), a small-for-gestational-age neonate (RR 0.622 (95% CI: 0.440-0.880); p=.007), and an increase in gestational length (SMD 0.312 (95% CI: 0.017-0.607); p=.038) and neonatal weight (SMD 0.428 (95% CI: 0.066-0.791); p=.020).Conclusions: LMWH has a secondary preventive effect on early or severe PE and improves neonatal outcomes. In the future, additional large multicenter studies will need to focus on high-risk PE groups by more accurate screening to obtain more information before clinical application.

Gene delivery in the cornea: in vitro & ex vivo evaluation of solid lipid nanoparticle-based vectors

AIM

Inflammation is a process that underlies sight-threatening ocular surface diseases, and gene supplementation with the plasmid that encodes for p-IL10 will allow the sustained de novo synthesis of the cytokine to occur in corneal cells, and provide a long-term anti-inflammatory effect. This work describes the development of solid lipid nanoparticle systems for the delivery of p-IL10 to transfect the cornea.

RESULTS

In vitro, vectors showed suitable features as nonviral vectors (size, ζ-potential, DNA binding, protection and release), and they were able to enter and transfect human corneal epithelial cells. Ex vivo, the vectors were found to transfect the epithelium, the stroma and the endothelium in rabbit corneal explants. Distribution of gene expression within the cell layers of the cornea depended on the composition of the four vectors evaluated.

CONCLUSION

Solid lipid nanoparticle-based vectors are promising gene delivery systems for corneal diseases, including inflammation.

Hypomethylation of tissue factor pathway inhibitor 2 in human placenta of preeclampsia

OBJECTIVES

To investigate the expression, DNA methylation status and its regulatory mechanism of tissue factor pathway inhibitor 2 (TFPI-2) in human placenta tissues of preeclampsia (PE).

MATERIAL AND METHODS

We studied the mRNA and protein expression and the promoter methylation levels of TFPI-2 in the PE placentas compared with those in the normal pregnant (NP) women. Quantitative real-time polymerase chain reaction, immunohistochemistry, western blot, and Sequenom MassARRAY were used for placenta tissue detection.

RESULTS

The expressions of TFPI-2 mRNA and protein were significantly elevated in the PE placentas when compared with those in the NP ones (P<0.05). Hypomethylation of the TFPI-2 promoter was detected both in PE patients and NP women, with a significant decrease in PE placentas (P=0.005). The methylation level was significantly decreased at CpG_6 (-168 to -167), CpG_15 (-98 to -97) and CpG_18.19 (-68 to -65) in PE patients than that in normal placentas (P<0.05). However, the expression of DNMT-1 didn't show significant difference between the two groups (P>0.05).

CONCLUSION

Over-expression of TFPI-2 and aberrant promoter mythylation status presented in the PE placentas, suggesting that epigenetic mechanism might contribute to the pathogenesis of PE.

Heparin exerts anti-apoptotic effects on uterine explants by targeting the endocannabinoid system

Miscarriage caused by Gram-negative bacteria infecting the female genital tract is one of the most common complications of human pregnancy. Intraperitoneal administration of LPS to 7-days pregnant mice induces embryo resorption after 24 h. Here, we show that LPS induced apoptosis on uterine explants from 7-days pregnant mice and that CB1 receptor was involved in this effect. On the other hand, heparin has been widely used for the prevention of pregnancy loss in women with frequent miscarriage with or without thrombophilia. Besides its anticoagulant properties, heparin exerts anti-inflammatory, immunomodulatory and anti-apoptotic effects. Here, we sought to investigate whether the administration of heparin prevented LPS-induced apoptosis in uterine explants from 7-days pregnant mice. We found that heparin enhanced cell survival in LPS-treated uterine explants and that this effect was mediated by increasing uterine FAAH activity. Taken together, our results point towards a novel mechanism involved in the protective effects of heparin.

Prevention of pre-eclampsia by low-molecular-weight heparin in addition to aspirin: a meta-analysis

OBJECTIVE

To estimate the impact of adding low-molecular-weight heparin (LMWH) or unfractionated heparin to low-dose aspirin started ≤ 16 weeks' gestation on the prevalence of pre-eclampsia (PE) and the delivery of a small-for-gestational-age (SGA) neonate.

METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) was performed by searching the medical databases PubMed, EMBASE, Web of Science and Cochrane Central. Pregnant women randomized to receive LMWH or unfractionated heparin in addition to low-dose aspirin were compared with those who received low-dose aspirin alone. Outcome measures were PE, severe PE, early-onset PE and SGA. Pooled relative risks (RRs) with 95% CI were calculated using a random-effects model.

RESULTS

Eight RCTs met the inclusion criteria; the indication for recruitment was previous recurrent miscarriage in five studies (three included women with thrombophilia) and a history of severe or early-onset PE in three studies (including women with thrombophilia in one). LMWH was administered in seven studies and unfractionated heparin in one. In women with a history of PE, treatment with LMWH and aspirin, compared with aspirin alone, was associated with a significant reduction in development of PE (three trials (n = 379); RR, 0.54 (95% CI, 0.31-0.92); P = 0.03) and in delivery of SGA neonates (two trials (n = 363); RR, 0.54 (95% CI, 0.32-0.91); P = 0.02). These outcomes were not significantly reduced in women with recurrent miscarriage who received LMWH and aspirin, compared with aspirin alone. The small number of studies precluded sensitivity analyses and the evaluation of publication biases. Blinding to the allocation treatment was absent in all RCTs.

CONCLUSIONS

Based on limited evidence, the addition of LMWH to low-dose aspirin could reduce the prevalence of PE and SGA in women with a history of PE. This observation should be the basis of a well-conducted future trial rather than a recommendation for immediate clinical application. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.