Based upon our demonstration that the smooth muscle cell-selective (SMC-selective) putative methyltransferase, Prdm6, interacts with myocardin-related transcription factor-A, we examined Prdm6's role in SMCs in vivo using cell type-specific knockout mouse models. Although SMC-specific depletion of Prdm6 in adult mice was well tolerated, Prdm6 depletion in Wnt1-expressing cells during development resulted in perinatal lethality and a completely penetrant patent ductus arteriosus (DA) phenotype. Lineage tracing experiments in Wnt1Cre2 Prdm6fl/fl ROSA26LacZ mice revealed normal neural crest-derived SMC investment of the outflow tract. In contrast, myography measurements on DA segments isolated from E18.5 embryos indicated that Prdm6 depletion significantly reduced DA tone and contractility. RNA-Seq analyses on DA and ascending aorta samples at E18.5 identified a DA-enriched gene program that included many SMC-selective contractile associated proteins that was downregulated by Prdm6 depletion. Chromatin immunoprecipitation-sequencing experiments in outflow tract SMCs demonstrated that 50% of the genes Prdm6 depletion altered contained Prdm6 binding sites. Finally, using several genome-wide data sets, we identified an SMC-selective enhancer within the Prdm6 third intron that exhibited allele-specific activity, providing evidence that rs17149944 may be the causal SNP for a cardiovascular disease GWAS locus identified within the human PRDM6 gene.

The ductus arteriosus (DA) immediately starts closing after birth. This dynamic process involves DA-specific properties, including highly differentiated smooth muscle, sparse elastic fibers, and intimal thickening (IT). Although several studies have demonstrated DA-specific gene expressions using animal tissues and human fetuses, the transcriptional profiles of the closing DA and the patent DA remain largely unknown. We performed transcriptome analysis using four human DA samples. The three closing DA samples exhibited typical DA morphology, but the patent DA exhibited aorta-like elastic lamellae and poorly formed IT. A cluster analysis revealed that samples were clearly divided into two major clusters, the closing DA and patent DA clusters, and showed distinct gene expression profiles in IT and the tunica media of the closing DA samples. Cardiac neural crest-related genes such as JAG1 were highly expressed in the tunica media and IT of the closing DA samples compared to the patent DA sample. Abundant protein expressions of jagged 1 and the differentiated smooth muscle marker calponin were observed in the closing DA samples but not in the patent DA sample. Second heart field-related genes such as ISL1 were enriched in the patent DA sample. These data indicate that the patent DA may have different cell lineages compared to the closing DA.

The ductus arteriosus, an essential embryonic blood vessel between the pulmonary artery and the descending aorta, constricts after birth or hatching and eventually closes to terminate embryonic circulation. Chicken embryos have two long ductus arteriosi, which anatomically differ from mammal ductus arteriosus. Each long ductus arteriosus is divided into two parts: the pulmonary artery-sided and descending aorta-sided ductus arteriosi. Although the pulmonary artery-sided and descending aorta-sided ductus arteriosi have distinct functional characteristics, such as oxygen responsiveness, the difference in their transcriptional profiles has not been investigated. We performed a DNA microarray analysis (GSE 120116 at NCBI GEO) with pooled tissues from the chicken pulmonary artery-sided ductus arteriosus, descending aorta-sided ductus arteriosus, and aorta at the internal pipping stage. Although several known ductus arteriosus-dominant genes such as tfap2b were highly expressed in the pulmonary artery-sided ductus arteriosus, we newly found genes that were dominantly expressed in the chicken pulmonary artery-sided ductus arteriosus. Interestingly, cluster analysis showed that the expression pattern of the pulmonary artery-sided ductus arteriosus was closer to that of the descending aorta-sided ductus arteriosus than that of the aorta, whereas the morphology of the descending aorta-sided ductus arteriosus was closer to that of the aorta than that of the pulmonary artery-sided ductus arteriosus. Subsequent pathway analysis with DAVID bioinformatics resources revealed that the pulmonary artery-sided ductus arteriosus showed enhanced expression of the genes involved in melanogenesis and tyrosine metabolism compared with the descending aorta-sided ductus arteriosus, suggesting that tyrosinase and the related genes play an important role in the proper differentiation of neural crest-derived cells during vascular remodeling in the ductus arteriosus. In conclusion, the transcription profiles of the chicken ductus arteriosus provide new insights for investigating the mechanism of ductus arteriosus closure.

Persistent patent ductus arteriosus (PDA) and clinically silent PDAs are relatively common congenital cardiac defects in humans. We report here the occurrence of symptomatic PDA in adults from a colony of genetically epilepsy-prone rats (GEPRs). Affected rats displayed severe ventral edema. Echocardiography revealed PDA in several animals. Necropsy findings included cardiomegaly, hepatic hyperemia and centrilobular necrosis indicative of passive congestion, and vascular changes consistent with pulmonary hypertension. All affected rats were descendants of one of two brother-sister breeding pairs established from a single litter in April 2000. Clinically silent PDAs were also detected in the colony. Histological examination of the ligamentum arteriosus showed normal vascular tissue in asymptomatic GEPR and Sprague-Dawley rats. PDAs are likely to have a genetic component in the GEPR colony and may provide a novel model for the study of pathogenesis and therapy of this condition.

This study investigated the characteristics of congenital rubella syndrome (CRS)-associated cardiac complications, particularly patent ductus arteriosus (PDA). We reviewed the medical records of patients with CRS who were admitted to the Children's Hospital 1 in Vietnam between December 2010 and December 2012, and patients with CRS who underwent PDA transcatheter occlusion therapy at the cardiology department between December 2009 and December 2015. We compared the characteristics of PDA treated with transcatheter closure between children with CRS (CRS-PDA) and those without CRS (non-CRS-PDA) who underwent PDA transcatheter closure between July 2014 and December 2015. One-hundred-and-eight children with CRS were enrolled. Cardiac defects (99%), cataracts (72%), and hearing impairment (7%) were detected. Fifty CRS-PDA and 290 non-CRS-PDA patients were examined. CRS-PDA patients had smaller median birthweight (p < 0.001), more frequent pulmonary (p < 0.001) and aortic stenosis (p < 0.001), higher main pulmonary artery pressure, and higher aortic pressure in systole/diastole (p < 0.001 for each) than did non-CRS-PDA patients. The proportion of tubular-type PDA was higher in CRS-PDA patients (16%) than in non-CRS-PDA patients (3%) (p = 0.020). Tubular-type PDA was frequently seen in patients with CRS and accompanied by pulmonary/systemic hypertension and pulmonary/aortic stenosis; in these patients, more cautious device selection is needed for transcatheter PDA closure.

To identify single-nucleotide polymorphisms (SNPs) in specific candidate genes associated with patent ductus arteriosus in term infants.

Chorioamnionitis has recently been reported as a risk factor for various neonatal diseases, including cerebral palsy, bronchopulmonary dysplasia, and necrotizing enterocolitis, but its effect on patent ductus arteriosus (PDA) is unclear. We performed a systematic review and meta-analysis to evaluate the effect of chorioamnionitis on PDA.

The Ductus Arteriosus (DA) is a fetal vessel that connects the aorta to the pulmonary artery ensuring that placental oxygenated blood is diverted from the lungs to the systemic circulation. Following exposure to oxygen (O2), in the first few days of life, the DA responds with a functional closure that is followed by anatomical closure. Here, we study human DA smooth muscle cells (DASMC) taken from 10 term infants during congenital heart surgery. Purification of these cells using flow cytometry ensured a pure population of DASMCs, which we confirmed as responsive to O2. An oxygen-induced increase in intracellular calcium of 18.1%±4.4% and SMC constriction (-27%±1.5% shortening) occurred in all cell lines within five minutes. These cells were maintained in either hypoxia (2.5% O2), mimicking in utero conditions or in normoxia (19% O2) mimicking neonate conditions. We then used 3' RNAsequencing to identify the transcriptome of DASMCs in each condition [1]. In this paper, we present the full differentially regulated gene list from this experiment.

To characterize the number and methods of closure of Persistent Ductus Arteriosus (PDA) over a span of 16 years in a third level maternity hospital.

Patent ductus arteriosus (PDA) is a congenital heart defect with an unclear etiology that occurs commonly among newborns. Adequately understanding the molecular pathogenesis of PDA can contribute to improved treatment and prevention. Plasma proteins may provide evidence to explore the molecular mechanisms of abnormal cardiac development.

Left ventricular systolic time intervals were recorded by a non-invasive technique, from the axillary artery, in 13 preterm infants with patent ductus arteriosus. At the onset of clinical symptoms, consistent with a large left-to right ductal shunt, the preejection intervals were shorter than in a control group of nine preterm infants without a patent ductus. The most pronounced difference was found in the shortening of the isovolumic contraction time, 10.7 msec in the ductus group compared with 22.4 msec in the control group. Ductal closure normalized the isovolumic contraction time to 22.1 msec. The very short preejection intervals, associated with a large ductal shunt, are suggested to reflect a combination of reduced aortic diastolic pressure and increased left ventricular filling pressure. In spite of increased volume load to the left ventricle there were no detectable changes in the systolic time intervals indicating impaired left ventricular function. The left ventricle seems to be competent to handle increased volume load in the presence of reduced afterload in preterm infants with symptomatic left-to right ductal shunts.

Patent ductus arteriosus (PDA) is common among Nigerian children. It is the second only to ventricular septal defect among congenital heart diseases in Nigeria children. The study centers are the only centers in Nigeria which are able to offer both transcatheter closure of PDA and surgical ligation. The study aims to compare both methods in terms of the demographics of the individuals, cost and outcome.

Patency of the ductus arteriosus (DA) is crucial for both fetal circulation and patients with DA-dependent congenital heart diseases (CHD). The Na+/Ca2+ exchanger 1 (NCX1) protein has been shown to play a key role in the regulation of vascular tone and is elevated in DA-dependent CHD. This current study was conducted to investigate the mechanisms underpinning the role of NCX1 in DA patency. Our data showed NCX1 expression was up-regulated in the DA of fetal mice. Up-regulation of NCX1 expression resulted in a concomitant decrease in cytosolic Ca2+ levels in human DA smooth muscle cells (DASMCs) and an inhibition of the proliferation and migration capacities of human DASMCs. Furthermore, treatment of DASMCs with KB-R7943, which can reduce Ca2+ influx, resulted in the inhibition of both cell proliferation and migration. These findings indicate that NCX1 may play a role in maintaining patent DA not only by preventing DA functional closure through reducing cytosolic Ca2+ level in DASMC but also by delaying the anatomical closure process. The latter delay is facilitated by the down-regulation of human DASMC proliferation and migration. It is also likely that a reduction in cytosolic Ca2+ levels inhibits the proliferation and migration capacities of human DASMCs in vitro.

Introduction: In premature neonates, the persistence of hemodynamically significant ductus arteriosus (hsPDA) can be associated with short- and long-term consequences, impairing their outcome. The correct strategy of management for such condition is under debate, especially regarding contraindications and/or side effects. In recent years, metabolomics was applied to several perinatal, pediatric, and adult conditions to investigate potential biomarkers of disease, which have become useful for early diagnosis and/or therapeutic management. Aim of the Study: The main purpose of our exploratory study was to asses, through 1H-NMR metabolomics analysis of urinary samples at birth, possible metabolic pathways differentiating, with a significant predictive power, those preterm neonates who will subsequently develop hsPDA and neonates of comparable gestational age (GA) who will undergo spontaneous ductal closure or the persistence of an irrelevant PDA (no-hsPDA). Moreover, we investigated potential prenatal or perinatal clinical factors potentially influencing the development of hsPDA. Materials and Methods: We enrolled n = 35 preterm neonates with GA between 24 and 32 weeks; urinary samples were collected within the first 12 h of life. Patients were closely monitored regarding intensive care, respiratory support, fluid balance and administered drugs; an echocardiogram was performed at 48-72 h. Results: Our results reported a significant correlation between lower GA at birth and the development of hsPDA. Moreover, neonates with GA ≤ 30w developing hsPDA were characterized by lower Apgar scores at 1' and 5', higher rates of perinatal asphyxia, higher need of delivery room resuscitation and subsequent surfactant administration. Interestingly, metabolomics analysis at birth detected a clear separation between the 1H-NMR urinary spectra of subjects GA ≤ 30w not developing hsPDA (n = 19) and those of subjects born at GA ≤ 30w in which hsPDA was confirmed at 48-72 h of life (n = 5). Conclusions: This is the first study applying metabolomics to investigate the PDA condition. Although preliminary and conducted on a limited sample, our results reveal that metabolomics could be a promising tool in the early identification of hsPDA, potentially superior to the clinical or laboratory predictive tools explored to date and even to the clinical observations and correlations in our sample, through the detection of specific urinary metabolites.

β3-adrenoreceptor (β3-AR), a G-protein coupled receptor, has peculiar regulatory properties in response to oxygen and widespread localization. β3-AR is expressed in the most frequent neoplasms, also occurring in pregnant women, and its blockade reduces tumor growth, indicating β3-AR-blockers as a promising alternative to antineoplastic drugs during pregnancy. However, β3-AR involvement in prenatal morphogenesis and the consequences of its blockade for the fetus remain unknown. In this study, after the demonstrated expression of β3-AR in endothelial and smooth muscle cells of ductus arteriosus (DA), C57BL/6 pregnant mice were acutely treated at 18.5 of gestational day (GD) with indomethacin or with the selective β3-AR antagonist SR59230A, or chronically exposed to SR59230A from 15.5 to 18.5 GD. Six hours after the last treatment, fetuses were collected. Furthermore, newborn mice were treated straight after birth with BRL37344, a β3-AR agonist, and sacrificed after 7 h. SR59230A, at the doses demonstrated effective in reducing cancer progression (10 and 20 mg/kg) in acute and chronic mode, did not induce fetal DA constriction and did not impair the DA ability to close after birth, whereas at the highest dose (40 mg/kg), it was shown to cause DA constriction and preterm-delivery. BRL37344 administered immediately after birth did not alter the physiological DA closure.

Maternal consumption of polyphenol-rich foods has been associated with fetal ductus arteriosus constriction (DAC), but safety of chocolate exposure in fetal life has not been studied. This experimental study tested the hypothesis that maternal cocoa consumption in late pregnancy causes fetal DAC, with possible associated antioxidant effects. Pregnant Wistar rats, at the 21st gestational day, received by orogastric tube cocoa (720 mg/Kg) for 12 h, indomethacin (10 mg/Kg), for 8 h, or only water, before cesaren section. Immediately after withdrawal, every thorax was obtained and tissues were fixed and stained for histological analysis. The ratio of the narrowest part of the pulmonary artery to the fetal ductus inner diameter and increased ductal inner wall thickness characterized ductal constriction. Substances reactive to thiobarbituric acid were quantified. Statistical analysis used ANOVA and Tukey test. Cocoa (n = 33) and indomethacin (n = 7) reduced fetal internal ductus diameter when compared to control (water, n = 25) (p < 0.001) and cocoa alone increased ductus wall thickness (p < 0.001), but no change was noted in enzymes activity. This pharmacological study shows supporting evidences that there is a cause and effect relationship between maternal consumption of cocoa and fetal ductus arteriosus constriction. Habitual widespread use of chocolate during gestation could account for undetected ductus constriction and its potentially severe consequences, such as perinatal pulmonary hypertension, cardiac failure and even death. For this reason, dietary guidance in late pregnancy to avoid high chocolate intake, to prevent fetal ductal constriction, may represent the main translational aspect of this study.

To identify genes affected by advancing gestation and racial/ethnic origin in human ductus arteriosus (DA).

We hypothesized that postnatal absolute nucleated red blood cell (aNRBC) counts would be elevated in premature infants with hemodynamically significant patent ductus arteriosus (PDA), reflecting intrauterine hypoxia. PDA severity was assessed and categorized echocardiographically. aNRBC counts were significantly correlated with ductal severity (Pearson correlation: P = .007). At the extremes, aNRBC levels were 3770 (728, 6015) hemodynamically significant PDA vs 865 (483, 2528) closed ductus.

The ductus arteriosus (DA) closes after birth to adapt to the robust changes in hemodynamics, which require intimal thickening (IT) to occur. The smooth muscle cells of the DA have been reported to play important roles in IT formation. However, the roles of the endothelial cells (ECs) have not been fully investigated. We herein focused on tissue-type plasminogen activator (t-PA), which is a DA EC dominant gene, and investigated its contribution to IT formation in the DA.

The optimal management strategy for patent ductus arteriosus in preterm infants remains a topic of debate. Available evidence for a treatment strategy might be biased by the delayed spontaneous closure of the ductus arteriosus in preterm infants, which appears to depend on patient characteristics. We performed a systematic review of all literature on PDA studies to collect patient characteristics and reported numbers of patients with a ductus arteriosus and spontaneous closure. Spontaneous closure rates showed a high variability but were lowest in studies that only included preterm infants with gestational ages below 28 weeks or birth weights below 1,000 g (34% on day 4; 41% on day 7) compared to studies that also included infants with higher gestational ages or higher birth weights (up to 55% on day 3 and 78% on day 7). The probability of spontaneous closure of the ductus arteriosus keeps increasing until at least 1 week after birth which favors delayed treatment of only those infants that do not show spontaneous closure. Better prediction of the spontaneous closure of the ductus arteriosus in the individual newborn is a key factor to find the optimal management strategy for PDA in preterm infants.