Celecoxib restores angiogenic factor expression at the maternal-fetal interface in the BPH/5 mouse model of preeclampsia

Reversal of maternal obesity attenuates hypoxia and improves placental development in the preeclamptic-like BPH/5 mouse model

Background

Women with obesity have higher risk of adverse pregnancy outcomes, including preeclampsia (PE). Late-gestational hypertension, aberrant fetoplacental development, and fetal growth restriction (FGR), hallmarks of PE, are observed spontaneously in BPH/5 mice. Similar to obese preeclamptic women, BPH/5 mice have higher visceral white adipose tissue (WAT) and circulating leptin. We hypothesized that attenuation of maternal obesity and serum leptin in pregnant BPH/5 mice will improve fetoplacental development by decreasing hypoxia markers and leptin expression at the maternal-fetal interface.

Methods

To test this hypothesis, BPH/5 mice were fed ad libitum (lib) and pair-fed (PF) to C57 ad lib controls beginning at embryonic day (e) 0.5. Hypoxia-related genes, hypoxia inducible factor (Hif) 1α, stem cell factor (Scf), heme oxygenase-1 (Ho-1), leptin (Lep), and leptin receptor (LepR) were assessed in e7.5 implantation sites.

Results

BPH/5 ad lib had 1.5 to 2-fold increase in Hif1α, Scf, and Ho-1 mRNA and a greater than 3-fold increase in leptin mRNA vs. C57 that was attenuated with PF. Exogenous leptin promoted Hif1α and Ho-1 mRNA expression in e7.5 decidua in vitro. While hypoxic conditions in vitro did not change decidual leptin mRNA. Furthermore, BPH/5 PF mice demonstrated improved fetal and placental outcomes later in gestation, with greater placental vascular area by e18.5 and attenuation of FGR.

Conclusion

In conclusion, pair-feeding BPH/5 mice beginning at conception may improve placental vasculature formation via decreased leptin and hypoxia-associated markers in this model. Future investigations are needed to better determine the effect of hypoxia and leptin on pregnancy outcomes in obese pregnant women.

Preeclampsia and Obesity-The Preventive Role of Exercise

Obesity is now recognized as a worldwide epidemic. An inadequate diet and reduced physical activity are acknowledged as the leading causes of excess body weight. Despite growing evidence that obesity is a risk factor for unsuccessful pregnancies, almost half of all women who become pregnant today are overweight or obese. Common complications of pregnancy in this group of women are preeclampsia and gestational hypertension. These conditions are also observed more frequently in women with excessive weight gain during pregnancy. Preeclampsia is one of the most serious pregnancy complications with an unpredictable course, which in its most severe forms, threatens the life and health of the mother and her baby. The early identification of the risk factors for preeclampsia development, including obesity, allows for the implementation of prophylaxis and a reduction in maternal and fetal complications risk. Additionally, preeclampsia and obesity are the recognized risk factors for developing cardiovascular disease in later life, so prophylaxis and treating obesity are paramount for their prevention. Thus, a proper diet and physical activity might play an essential role in the prophylaxis of preeclampsia in this group of women. Limiting weight gain during pregnancy and modifying the metabolic risk factors with regular physical exercise creates favorable metabolic conditions for pregnancy development and benefits the elements of the pathogenetic sequence for preeclampsia development. In addition, it is inexpensive, readily available and, in the absence of contraindications to its performance, safe for the mother and fetus. However, for this form of prevention to be effective, it should be applied early in pregnancy and, for overweight and obese women, proposed as an essential part of planning pregnancy. This paper aims to present the mechanisms of the development of hypertension in pregnancy in obese women and the importance of exercise in its prevention.

The preventive effects of aspirin on preeclampsia based on network pharmacology and bioinformatics

This study aimed to reveal the key targets and molecular mechanisms of aspirin in preventing preeclampsia. We used bioinformatics databases to collect the candidate targets for aspirin and preeclampsia. The biological functions and signaling pathways of the intersecting targets were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Then, the hub targets were identified by cytoscape plugin cytoHubba from the protein-protein interaction network. We collected 90 targets for aspirin in preventing preeclampsia. The biological processes of the intersecting targets are mainly involved in xenobiotic metabolic process, inflammatory response, negative regulation of apoptotic process, and protein phosphorylation. The highly enriched pathways were FoxO signaling pathway, circadian rhythm, insulin resistance, arachidonic acid metabolism, and drug metabolism-cytochrome P450. The hub targets for aspirin in preventing preeclampsia were tumor protein p53 (TP53), C-X-C motif chemokine ligand 8 (CXCL8), mitogen-activated protein kinase 3 (MAPK3), mitogen-activated protein kinase 1 (MAPK1), mitogen-activated protein kinase 14 (MAPK14), epidermal growth factor receptor (EGFR), estrogen receptor (ESR1), and prostaglandin-endoperoxide synthase 2 (PTGS2). Molecular docking results showed good bindings between the proteins and aspirin. In conclusion, these findings highlight the key targets and molecular mechanisms of aspirin in preventing preeclampsia.

Levels of plasma Quaking and cyclooxygenase-2 predict in-stent restenosis in patients with coronary artery disease after percutaneous coronary intervention

OBJECTIVES

Percutaneous coronary intervention (PCI) is one of the important methods for the treatment of coronary artery disease (CAD). In-sent restenosis (ISR) after PCI for patients suffered from CAD is considered to be an essential factor affecting long-term outcomes and prognosis of this disease. This study aims to investigate the correlation between plasma Quaking (QKI) and cyclooxygenase-2 (COX-2) levels and ISR in patients with CAD.

METHODS

A total of 218 consecutive CAD patients who underwent coronary angiography and coronary arterial stenting from September 2019 to September 2020 in the Department of Cardiology of Xiangya Hospital of Central South University were enrolled in this study, and 35 matched individuals from the physical examination center were served as a control group. After admission, clinical data of these 2 groups were collected. Plasma QKI and COX-2 levels were measured by enzyme linked immunosorbent assay (ELISA). Follow-up angiography was performed 12 months after PCI. CAD patients were divided into a NISR group (n=160) and an ISR group (n=58) according to the occurrence of ISR based on the coronary angiography. The clinical data, coronary angiography, and stent features between the NISR group and the ISR group were compared, and multivariate logistic regression was used to explore the factors influencing ISR. The occurrence of major adverse cardiovascular events (MACE) 1 year after operation was recorded. Fifty-eight patients with ISR were divided into an MACE group (n=24) and a non-MACE group (n=34), classified according to the occurrence of MACE, and the plasma levels of QKI and COX-2 were compared between the 2 groups. Receiver operating characteristic (ROC) curves were utilized to analyze the diagnostic value of plamsa levels of QKI and COX-2 for ISR and MACE occurrences in patients after PCI.

RESULTS

Compared with control group, plasma levels of QKI and COX-2 in the CAD group decreased significantly (all P<0.001). Compared with the NISR group, the plasma levels of QKI and COX-2 also decreased obviously in the ISR group (all P<0.001), while the levels of high sensitivity C-reactive protein (hs-CRP) and glycosylated hemoglobin (HbAlc) significantly increased (all P<0.001). The level of COX-2 was negatively correlated with hs-CRP (r=-0.385, P=0.003). Multivariate logistic regression analysis showed that high level of plasma QKI and COX-2 were protective factors for in-stent restenosis after PCI, while hs-CRP was a risk factor. ROC curve analysis showed that the sensitivity and specificity of plasma QKI for evaluating the predictive value of ISR were 77.5% and 66.5%, respectively, and the sensitivity and specificity of plasma COX-2 for evaluating the predictive value of ISR were 80.0% and 70.7%, respectively. The sensitivity and specificity of plasma QKI combined with COX-2 for evaluating the predictive value of ISR were 81.3% and 74.1%, respectively. The sensitivity and specificity of plasma QKI for evaluating the prognosis of ISR were 75.0% and 64.7%, respectively. The sensitivity and specificity of plasma COX-2 for evaluating the prognosis of ISR were 75.0% and 70.6%, respectively. The sensitivity and specificity of plasma QKI combined with COX-2 for prognostic evaluation of ISR were 81.7% and 79.4%, respectively. The sensitivity and specificity of plasma COX-2 combined with QKI for evaluating ISR and MACE occurrences in patients after PCI were better than those of COX-2 or QKI alone (P<0.001).

CONCLUSIONS

High level of plasma QKI and COX-2 might be a protective factor for ISR, which can also predict ISR patient's prognosis.

An Overview of Obesity, Cholesterol, and Systemic Inflammation in Preeclampsia

Preeclampsia (PE), an inflammatory state during pregnancy, is a significant cause of maternal and fetal morbidity and mortality. Adverse outcomes associated with PE include hypertension, proteinuria, uterine/placental abnormalities, fetal growth restriction, and pre-term birth. Women with obesity have an increased risk of developing PE likely due to impaired placental development from altered metabolic homeostasis. Inflammatory cytokines from maternal adipose tissue and circulating cholesterol have been linked to systemic inflammation, hypertension, and other adverse outcomes associated with PE. This review will summarize the current knowledge on the role of nutrients, obesity, and cholesterol signaling in PE with an emphasis on findings from preclinical models.

The BPH/5 Mouse Model of Superimposed Preeclampsia Is Not a Model of HELLP Syndrome

Preeclampsia (PE) is a multisystemic disease of pregnancy affecting 2-8% of women worldwide. PE-induced liver disease is a rare but important complication of pregnancy. The pathogenesis of liver dysfunction in PE is poorly understood, but is correlated with dysregulated angiogenic, inflammatory, and hypoxic events in the early phase of placental development. Because BPH/5 mice develop the maternal and fetal hallmarks of PE during pregnancy, we hypothesized that they may also share the clinicopathologic findings of the human PE-associated hemolysis elevated liver transaminases low platelets (HELLP) syndrome. Using this model, we determined that microangiopathic hemolysis, thrombocytopenia, and elevated liver enzymes do not occur in mid to late gestation. Pregnant BPH/5 mice do not develop histologic evidence of hepatic inflammation, but they do have increased microsteatosis scores at preconception and in mid to late gestation that progress to macrosteatosis in a subset of mice in late gestation. The transcriptional upregulation of TNF-α, CXCL-10, and TLR-2 occurs in mid gestation prior to the onset of macrosteatosis. The BPH/5 female mouse is not a model of HELLP syndrome, but may be a model of fatty liver disease associated with pregnancy.

Rodent models of hypertension

Elevated blood pressure (BP), or hypertension, is the main risk factor for cardiovascular disease. As a multifactorial and systemic disease that involves multiple organs and systems, hypertension remains a challenging disease to study. Models of hypertension are invaluable to support the discovery of the specific genetic, cellular and molecular mechanisms underlying essential hypertension, as well as to test new possible treatments to lower BP. Rodent models have proven to be an invaluable tool for advancing the field. In this review, we discuss the strengths and weaknesses of rodent models of hypertension through a systems approach. We highlight the ways how target organs and systems including the kidneys, vasculature, the sympathetic nervous system (SNS), immune system and the gut microbiota influence BP in each rodent model. We also discuss often overlooked hypertensive conditions such as pulmonary hypertension and hypertensive-pregnancy disorders, providing an important resource for researchers.

Genotypic analysis of the female BPH/5 mouse, a model of superimposed preeclampsia

Animal models that recapitulate human diseases and disorders are widely used to investigate etiology, diagnosis, and treatment of those conditions in people. Disorders during pregnancy are particularly difficult to explore as interventions in pregnant women are not easily performed. Therefore, models that allow for pre-conception investigations are advantageous for elucidating the mechanisms involved in adverse pregnancy outcomes that are responsible for both maternal and fetal morbidity, such as preeclampsia. The Blood Pressure High (BPH)/5 mouse model has been used extensively to study the pathogenesis of preeclampsia. The female BPH/5 mouse is obese with increased adiposity and borderline hypertension, both of which are exacerbated with pregnancy making it a model of superimposed preeclampsia. Thus, the BPH/5 model shares traits with a large majority of women with pre-existing conditions that predisposes them to preeclampsia. We sought to explore the genome of the BPH/5 female mouse and determine the genetic underpinnings that may contribute to preeclampsia-associated phenotypes in this model. Using a whole genome sequencing approach, we are the first to characterize the genetic mutations in BPH/5 female mice that make it unique from the closely related BPH/2 model and the normotensive background strain, C57Bl/6. We found the BPH/5 female mouse to be uniquely different from BPH/2 and C57Bl/6 mice with a genetically complex landscape. The majority of non-synonymous consequences within the coding region of BPH/5 females were missense mutations found most abundant on chromosome X when comparing BPH/5 and BPH/2, and on chromosome 8 when comparing BPH/5 to C57Bl/6. Genetic mutations in BPH/5 females largely belong to immune system-related processes, with overlap between BPH/5 and BPH/2 models. Further studies examining each gene mutation during pregnancy are warranted to determine key contributors to the BPH/5 preeclamptic-like phenotype and to identify genetic similarities to women that develop preeclampsia.

Regulation of Uterine Spiral Artery Remodeling: a Review

Extravillous trophoblast remodeling of the uterine spiral arteries is essential for promoting blood flow to the placenta and fetal development, but little is known about the regulation of this process. A defect in spiral artery remodeling underpins adverse conditions of human pregnancy, notably early-onset preeclampsia and fetal growth restriction, which result in maternal and fetal morbidity and mortality. Many in vitro studies have been conducted to determine the ability of growth and other factors to stimulate trophoblast cells to migrate across a synthetic membrane. Clinical studies have investigated whether the maternal levels of various factors are altered during abnormal human pregnancy. Animal models have been established to assess the ability of various factors to recapitulate the pathophysiological symptoms of preeclampsia. This review analyzes the results of the in vitro, clinical, and animal studies and describes a nonhuman primate experimental paradigm of defective uterine artery remodeling to study the regulation of vessel remodeling.

Complement in Reproductive White Adipose Tissue Characterizes the Obese Preeclamptic-Like BPH/5 Mouse Prior to and During Pregnancy

Preeclampsia (PE) is a serious hypertensive disorder of pregnancy characterized by abnormal placental development with an unknown etiology. To better understand which women will develop PE, a number of maternal risk factors have been identified, including obesity. Visceral white adipose tissue (WAT) contains inflammatory mediators that may contribute to PE. To explore this, we utilized the blood pressure high (BPH)/5 mouse model of superimposed PE that spontaneously recapitulates the maternal PE syndrome. We hypothesized that BPH/5 visceral WAT adjacent to the female reproductive tract (reproductive WAT) is a source of complement factors that contribute to the inflammatory milieu and angiogenic imbalance at the maternal-fetal interface in this model and in preeclamptic women. To test our hypothesis, we calorie-restricted BPH/5 females for two weeks prior to pregnancy and the first seven days of pregnancy, which attenuated complement component 3 (C3) but not complement factor B, nor complement factor D, (adipsin) in the reproductive WAT or the implantation site in BPH/5. Furthermore, calorie restriction during pregnancy restored vascular endothelial and placental growth factor mRNA levels in the BPH/5 implantation site. These data show maternal reproductive WAT may be a source of increased C3 during pregnancy, which is increased at the maternal-fetal interface in preeclamptic BPH/5 mice. It also suggests that calorie restriction could regulate inflammatory mediators thought to contribute to placental dysfunction in PE. Future studies are necessary to examine the effect of calorie restriction on C3 throughout pregnancy and the role of maternal obesity in PE.

From animal models to patients: the role of placental microRNAs, miR-210, miR-126, and miR-148a/152 in preeclampsia

Placental microRNAs (miRNAs) regulate the placental transcriptome and play a pathological role in preeclampsia (PE), a hypertensive disorder of pregnancy. Three PE rodent model studies explored the role of placental miRNAs, miR-210, miR-126, and miR-148/152 respectively, by examining expression of the miRNAs, their inducers, and potential gene targets. This review evaluates the role of miR-210, miR-126, and miR-148/152 in PE by comparing findings from the three rodent model studies with in vitro studies, other animal models, and preeclamptic patients to provide comprehensive insight into genetic components and pathological processes in the placenta contributing to PE. The majority of studies demonstrate miR-210 is upregulated in PE in part driven by HIF-1α and NF-κBp50, stimulated by hypoxia and/or immune-mediated processes. Elevated miR-210 may contribute to PE via inhibiting anti-inflammatory Th2-cytokines. Studies report an up- and downregulation of miR-126, arguably reflecting differences in expression between cell types and its multifunctional capacity. MiR-126 may play a pro-angiogenic role by mediating the PI3K-Akt pathway. Most studies report miR-148/152 family members are upregulated in PE. Evidence suggests they may inhibit DNA methylation of genes involved in metabolic and inflammatory pathways. Given the genetic heterogeneity of PE, it is unlikely that a single placental miRNA is a suitable therapeutic target for all patients. Investigating miRNAs in PE subtypes in patients and animal models may represent a more appropriate approach going forward. Developing methods for targeting placental miRNAs and specific placental cell types remains crucial for research seeking to target placental miRNAs as a novel treatment for PE.

Dysregulation of Complement Activation and Placental Dysfunction: A Potential Target to Treat Preeclampsia?

Preeclampsia is one of the leading causes of maternal and neonatal mortality and morbidity worldwide, affecting 2–8% of all pregnancies. Studies suggest a link between complement activation and preeclampsia. The complement system plays an essential role in the innate immunity, leading to opsonization, inflammation, and elimination of potential pathogens. The complement system also provides a link between innate and adaptive immunity and clearance of immune complexes and apoptotic cells. During pregnancy there is increased activity of the complement system systemically. However, locally at the placenta, complement inhibition is crucial for the maintenance of a normal pregnancy. Inappropriate or excessive activation of the complement system at the placenta is likely involved in placental dysfunction, and is in turn associated with pregnancy complications like preeclampsia. Therefore, modulation of the complement system could be a potential therapeutic target to prevent pregnancy complications such as preeclampsia. This review, based on a systematic literature search, gives an overview of the complement system and its activation locally in the placenta and systemically during healthy pregnancies and during complicated pregnancies, with a focus on preeclampsia. Furthermore, this review describes results of animal and human studies with a focus on the complement system in pregnancy, and the role of the complement system in placental dysfunction. Various clinical and animal studies provide evidence that dysregulation of the complement system is associated with placental dysfunction and therefore with preeclampsia. Several drugs are used for prevention and treatment of preeclampsia in humans and animal models, and some of these drugs work through complement modulation. Therefore, this review further discusses these studies examining pharmaceutical interventions as treatment for preeclampsia. These observations will help direct research to generate new target options for prevention and treatment of preeclampsia, which include direct and indirect modulation of the complement system.

Gene expression and DNA methylation changes in BeWo cells dependent on tumor necrosis factor-α and insulin-like growth factor-I

Pregnant women with increased insulin resistance, characterized by elevated levels of tumor necrosis factor-alpha (TNF-α) and insulin-like growth factor-I (IGF-I), are at high risk of preeclampsia. We hypothesized that TNF-α and IGF-I affect the placentas and cause pathological changes leading to preeclampsia. To understand the genetic and epigenetic effects of TNF-α and IGF-I on trophoblast cells, gene expression microarray and DNA methylation array of BeWo cells stimulated by TNF-α (100 pg/ml, 100 ng/ml) and IGF-I (100 ng/ml) were conducted. Microarray analysis revealed the differential gene expression patterns in BeWo cells co-stimulated by TNF-α and IGF-I. Enrichment analysis identified the terms associated with NF-kappa B signaling pathways and arachidonic acid cascades such as PTGS2 and PTGER2. DNA methylation array revealed the distinct CpG methylation pattern in BeWo cells stimulated by high-TNF-α and IGF-I, while neither of them showed independent effects. Enrichment analysis identified the terms associated with major histocompatibility complex proteins. Integration of transcriptome and DNA methylome analyses identified three differentially expressed genes with significant DNA methylation change: C3, GP1BA, and NFKBIE, which are all possibly associated with pathogenesis of preeclampsia. In conclusion, co-stimulation of TNF-α and IGF-I induced the genetic and epigenetic changes associated with preeclampsia in BeWo cells. The results suggested that BeWo cells stimulated by TNF-α and IGF-I is a good in vitro model of preeclamptic placenta in pregnancy with increased insulin resistance.

Spontaneous superimposed preeclampsia: chronology and expression unveiled by temporal transcriptomic analysis

Preeclampsia (PE), a multifactorial pregnancy-specific syndrome accounting for up to 8% of pregnancy complications, is a leading cause of maternal and fetal morbidity and mortality. PE is also associated with long-term risk of hypertension and stroke for both mother and fetus. Currently, the only "cure" is delivery of the baby and placenta, largely because the pathogenesis of PE is not yet fully understood. PE is associated with impaired vascular remodeling at the maternal-fetal interface and placental insufficiency; however, specific factors contributing to this impairment have not been identified. To identify molecular pathways involved in PE, we examined temporal transcriptomic changes occurring within the uterus, uterine implantation sites, and placentae from the Dahl salt-sensitive (Dahl S) rat model of superimposed PE compared with Sprague Dawley (SD) rats. We hypothesized that targeted gene analysis and whole transcriptome analysis would identify genetic factors that contribute to development of the preeclamptic phenotype in the Dahl S rat and unveil novel biomarkers, therapeutic targets, and mechanistic pathways in PE. Quantitative real-time PCR (qRT-PCR) and whole genome microarray analysis were performed on isolated total RNA from uterus (day 0), uterine implantation sites (days 7 and 10), and placenta (days 14 and 20). We found 624, 332, 185, and 366 genes to be differentially expressed between Dahl S (PE) and SD (normal pregnancy) on days 0, 7, 10, and 14, respectively. Our data revealed numerous pathways that may play a role in the pathophysiology of spontaneous superimposed PE and allow for further investigation of novel therapeutic targets and biomarker development.

Dyslipidemia and the role of adipose tissue in early pregnancy in the BPH/5 mouse model for preeclampsia

The hypertensive pregnancy disorder preeclampsia (PE) is a leading cause of fetal and maternal morbidity/mortality. Obesity increases the risk to develop PE, presumably via the release of inflammatory mediators from the adipose tissue, but the exact etiology remains largely unknown. Using obese PE-like blood pressure high subline 5 (BPH/5) and lean gestational age-matched C57Bl6 mice, we aimed to obtain insight into differential reproductive white adipose tissue (rWAT) gene expression, circulating lipids and inflammation at the maternal-fetal interface during early pregnancy. In addition, we investigated the effect of 7 days 25% calorie restriction (CR) in early pregnancy on gene expression in rWAT and implantation sites. Compared with C57Bl6, female BPH/5 are dyslipidemic before pregnancy and show an amplification of rWAT mass, circulating cholesterol, free fatty acids, and triacylglycerol levels throughout pregnancy. RNA sequencing showed that pregnant BPH/5 mice have elevated gene enrichment in pathways related to inflammation and cholesterol biosynthesis at embryonic day (e) 7.5. Expression of cholesterol-related HMGCS1, MVD, Cyp51a1, and DHCR was validated by quantitative reverse-transcription-polymerase chain reaction. CR during the first 7 days of pregnancy restored the relative mRNA expression of these genes to a level comparable to C57Bl6 pregnant females and reduced the expression of circulating leptin and proinflammatory prostaglandin synthase 2 in both rWAT and implantation sites in BPH/5 mice at e7.5. Our data suggest a possible role for rWAT in the dyslipidemic state and inflammatory uterine milieu that might underlie the pathogenesis of PE. Future studies should further address the physiological functioning of the adipose tissue in relation to PE-related pregnancy outcomes.