MicroRNAs Clustered within the 14q32 Locus Are Associated with Endothelial Damage and Microparticle Secretion in Bicuspid Aortic Valve Disease

miR-130a expression is related to aortic dilation in bicuspid aortic valve children

BACKGROUND

Bicuspid aortic valve disease (BAV) is present in 0.5-2% of the population and can promote aortic dilation, eventually leading to fatal consequences. Although some biomarkers have been proposed in adults, no studies have tested these candidates in children. We aimed to evaluate four miRNAs previously described to be related to BAV disease and aortic dilation in adults in a paediatric cohort.

METHODS

Eighty participants ≤17 years old (4-17; mean 12) were included. From the BAV group, 40% had a dilated aorta (z score >2). RT‒qPCR were performed in plasma samples to quantify miR-122, miR-130a, miR-486, and miR-718 using the delta-delta Ct method. Functional and enrichment analyses of miR-130a were also performed.

RESULTS

miR-130a expression in plasma was found to be significantly lower in BAV patients with a dilated aorta versus nondilated patients (p = 0.008) and healthy TAV controls (p = 0.004). Furthermore, miR-130a expression in plasma was inversely correlated with ascending aorta (r = 0.318, p = 0.004) and aortic root z scores (r = 0.322; p = 0.004). Enrichment analysis showed that miR-130a target genes are related to the TGFβ signalling pathway.

CONCLUSIONS

miR-130a expression in plasma is decreased in aortic-dilated BAV children compared to nondilated BAV children, helping differentiate low- to high-risk patients.

IMPACT

miR-130a expression in plasma is related to aortic dilation in bicuspid aortic valve (BAV) children. To our knowledge, this is the first study that analyses miRNA patterns in bicuspid aortic valve children with aortic dilation. miR-130a expression in plasma could be a biomarker in order to help differentiate low-to high-risk BAV children, which is vitally important for advanced care planning.

Glycoprotein and Lipoprotein Profiles Assessed by 1H-NMR and Its Relation to Ascending Aortic Dilatation in Bicuspid Aortic Valve Disease

INTRODUCTION

The bicuspid aortic valve (BAV) confers a high risk of ascending aorta dilatation (AAoD), although its progression seems highly variable. Furthermore, the implication of lipoprotein metabolism and inflammation in the mechanisms that underlie AAoD is not fully established. The aim of this study consisted of evaluating the impact of the lipoprotein and glycoprotein profiles in AAOD as well as its progression in BAV aortopathy.

METHODS

Using 1H-nuclear magnetic resonance (1H-NMR), we analyzed and compared the lipoprotein and glycoprotein profiles of plasma samples from 152 BAV patients with dilated and nondilated ascending aorta. Additionally, these profiles were also compared for 119 of these patients who were prospectively followed-up clinically and by echocardiography in the long-term (5 years). Ascending aorta dilation velocity (mm/year) was calculated for this analysis.

RESULTS

Several parameters related to the lipoprotein profile including remnant cholesterol, small LDL and IDL-cholesterol were found to be significantly increased in the dilated group compared to those in the nondilated group. The glycoprotein A-nuclear magnetic resonance (NMR) signal, a novel inflammation biomarker, was also observed to be increased in the dilated group. After performing multivariate analysis, remnant cholesterol remained an independent variable related to AAoD. In the long-term follow-up, proatherogenic lipoprotein parameters were related to ascending aorta dilatation velocity ascending. After a lineal regression analysis, non-HDL particles remained as an independent predictor of ascending aorta dilation velocity.

CONCLUSIONS

Patients with BAV and AAoD presented a more pro-atherogenic profile assessed by 1H-NMR, especially related to triglyceride-rich lipoproteins. This pro-atherogenic profile seems to contribute to the higher growth rate of ascending aorta diameter.

Patients with Bicuspid Aortopathy and Aortic Dilatation

(1) Background: Bicuspid aortic valve (BAV) is the most frequent congenital cardiac disease. Alteration of ascending aorta diameter is a consequence of shear stress alterations due to haemodynamic abnormalities developed from inadequate valve cusp coaptation. (2) Objective: This narrative review aims to discuss anatomical, pathophysiological, genetical, ultrasound, and radiological aspects of BAV disease, focusing on BAV classification related to imaging patterns and flux models involved in the onset and developing vessel dilatation. (3) Methods: A comprehensive search strategy was implemented in PubMed from January to May 2022. English language articles were selected independently by two authors and screened according to the following criteria. (4) Key Contents and Findings: Ultrasound scan is the primary step in the diagnostic flowchart identifying structural and doppler patterns of the valve. Computed tomography determines aortic vessel dimensions according to the anatomo-pathology of the valve. Magnetic resonance identifies hemodynamic alterations. New classifications and surgical indications derive from these diagnostic features. Currently, indications correlate morphological results, dissection risk factors, and genetic alterations. Surgical options vary from aortic valve and aortic vessel substitution to aortic valve repair according to the morphology of the valve. In selected patients, transcatheter aortic valve replacement has an even more impact on the treatment choice. (5) Conclusions: Different imaging approaches are an essential part of BAV diagnosis. Morphological classifications influence the surgical outcome.

MicroRNAs as Biomarkers for Birth Defects

It is estimated that 2-4% of live births will have a birth defect (BD). The availability of biomarkers for the prenatal detection of BDs will facilitate early risk assessment, prompt medical intervention and ameliorating disease severity. miRNA expression levels are often found to be altered in many diseases. There is, thus, a growing interest in determining whether miRNAs, particularly extracellular miRNAs, can predict, diagnose, or monitor BDs. These miRNAs, typically encapsulated in exosomes, are released by cells (including those of the fetus and placenta) into the extracellular milieu, such as blood, urine, saliva and cerebrospinal fluid, thereby enabling interaction with target cells. Exosomal miRNAs are stable, protected from degradation, and retain functionality. The observation that placental and fetal miRNAs can be detected in maternal serum, provides a strong rationale for adopting miRNAs as noninvasive prenatal biomarkers for BDs. In this mini-review, we examine the current state of research involving the use of miRNAs as prognostic and diagnostic biomarkers for BD.

MicroRNAs involve in bicuspid aortic aneurysm: pathogenesis and biomarkers

The incidence of bicuspid aortic valves (BAV) is high in the whole population, BAV-related thoracic aortic aneurysm (TAA) is accompanied by many adverse vascular events. So far, there are two key points in dealing with BAV-related TAA. First is fully understanding on its pathogenesis. Second is optimizing surgical intervention time. This review aims to illustrate the potential role of miRNAs in both aspects, that is, how miRNAs are involved in the occurrence and progression of BAV-related TAA, and the feasibilities of miRNAs as biomarkers.

Bicuspid Aortic Valve and Endothelial Dysfunction: Current Evidence and Potential Therapeutic Targets

Bicuspid aortic valve (BAV), the most frequent congenital heart malformation, is characterized by the presence of a two-leaflet aortic valve instead of a three-leaflet one. BAV disease progression is associated with valvular dysfunction (in the form of stenosis or regurgitation) and aortopathy, which can lead to aneurysm and aortic dissection. This morphological abnormality modifies valve dynamics and promotes eccentric blood flow, which gives rise to alterations of the flow pattern and wall shear stress (WSS) of the ascending aorta. Recently, evidence of endothelial dysfunction (ED) in BAV disease has emerged. Different studies have addressed a reduced endothelial functionality by analyzing various molecular biomarkers and cellular parameters in BAV patients. Some authors have found impaired functionality of circulating endothelial progenitors in these patients, associating it with valvular dysfunction and aortic dilation. Others focused on systemic endothelial function by measuring artery flow-mediated dilation (FMD), showing a reduced FMD in BAV individuals. Novel biomarkers like increased endothelial microparticles (EMP), which are related to ED, have also been discovered in BAV patients. Finally, latest studies indicate that in BAV, endothelial-to-mesenchymal transition (EndoMT) may also be de-regulated, which could be caused by genetic, hemodynamic alterations, or both. Different hypothesis about the pathology of ED in BAV are nowadays being debated. Some authors blamed this impaired functionality just on genetic abnormalities, which could lead to a pathological aorta. Nevertheless, thanks to the development of new and high-resolution imaging techniques like 4D flow MRI, hemodynamics has gained great attention. Based on latest studies, alterations in blood flow seem to cause proper modification of the endothelial cells (ECs) function and morphology. It also seems to be associated with aortic dilation and decreased vasodilators expression, like nitric oxide (NO). Although nowadays ED in BAV has been reported by many, it is not clear which its main cause may be. Comprehending the pathways that promote ED and its relevance in BAV could help further understand and maybe prevent the serious consequences of this disease. This review will discuss the ED present in BAV, focusing on the latest evidence, biomarkers for ED and potential therapeutic targets (Figure 1).

Plasma Metabolomic Profiling Associates Bicuspid Aortic Valve Disease and Ascending Aortic Dilation with a Decrease in Antioxidant Capacity

BACKGROUND

The bicuspid aortic valve (BAV) is the most common cardiac congenital disease and is associated with an increased risk of developing ascending aorta dilation; which can have fatal consequences. Currently; no established risk biomarkers exist to facilitate the diagnosis and prognosis of BAV.

METHODS

Using an untargeted metabolomic approach; we identified the levels of metabolites in plasma samples and compared them depending on the bicuspid or tricuspid morphology of the aortic valve. Including those patients with ascending aortic dilation and/or aortic stenosis (n = 212), we analyzed the role possibly played by alpha-Tocopherol in BAV disease; considering its association with the pathophysiological characteristics of BAV and biomarkers related to inflammation, oxidative stress and endothelial damage, as well as characteristics related to alpha-Tocopherol functionality and metabolism.

RESULTS

We found that BAV patients; especially those with ascending aortic dilation; presented lower antioxidant capacity; as determined by decreased plasma levels of alpha-Tocopherol; paraoxonase 1 and high-density lipoprotein (HDL), as well as increased levels of C-reactive protein (CRP; a biomarker of inflammation) and endothelial microparticles (EMPs; an endothelial damage biomarker). By applying random forest analyses; we evaluated the significant screening capacity of alpha-Tocopherol; CRP and EMPs to classify patients depending on the morphology of the aortic valve.

DISCUSSION

Our findings support the role of decreased antioxidant capacity; increased inflammation and endothelial damage in the pathogenesis of BAV and the progression of aortic dilation. Moreover; determining the plasma levels of alpha-Tocopherol; CRP and EMPs could improve BAV diagnosis in large populations.

miRMap: Profiling 14q32 microRNA Expression and DNA Methylation Throughout the Human Vasculature

Aims: MicroRNAs are regulators of (patho)physiological functions with tissue-specific expression patterns. However, little is known about inter-vascular differences in microRNA expression between blood vessel types or vascular beds. Differences in microRNA expression could influence cardiovascular pathophysiology at specific sites in the vasculature. Therefore, we aimed to map expression profiles of vasoactive 14q32 microRNAs throughout the human vasculature, as well as expression of vasoactive target genes of the 14q32 microRNAs. Furthermore, we aimed to map the DNA methylation status of the 14q32 locus, which has been linked to cardiovascular disease. Methods and Results: We collected 109 samples from different blood vessels, dissected during general surgery. Expression of a representative set of 17 14q32 microRNAs was measured in each sample. All 17 microRNAs showed a unique expression pattern throughout the vasculature. 14q32 microRNA expression was highest in lower limb vessels and lowest in head and neck vessels. All 17 microRNAs were expressed more abundantly in arteries than in veins. Throughout the human vasculature, we observed trends toward an inverse correlation between expression levels of the 14q32 microRNAs and their vasoactive target genes. DNA methylation of the 3 Differentially Methylated Regions (DMRs) along the 14q32 locus did not associate with primary or mature microRNA expression. However, hyper-methylation in venous coronary artery bypass grafts compared to arterial bypass grafts was observed in the Intergenic-DMR and MEG3-DMR. In patients with end-stage peripheral arterial disease we found differential DNA methylation throughout all DMRs in their lower limb veins. These findings were confirmed in a mouse model for vein-graft disease in which we found regulated 14q32 DNA methylation during the active phase of vascular remodeling. In ischemic tissues of a murine hind limb ischemia model we observed an increase in DNA methylation associated with increased ischemia over time. Conclusions: We show that 14q32 microRNAs are abundantly expressed in the human vasculature and that expression differs significantly between different blood vessels. 14q32 DNA methylation also varies throughout the vasculature and is associated with vascular health, independently of microRNA levels. These findings could have important implications for future research and for future site-specific targeting of epigenetics-based therapeutics.

microRNAs in bicuspid aortic valve associated aortopathy: Recent advances and future perspectives

The risk of acute aortic events in patients with bicuspid aortic valve (BAV) constitutes a medical concern in terms of timing and surgical decision. During the past years, there has been a growing interest in the potential of microRNAs (miRNAs) as crucial epigenetic factors in multiple cellular processes associated with BAV aortopathy. Nevertheless, there are still challenges that need to be overcome before miRNAs could enter clinical practice, and further validation studies in larger and well-defined BAV cohorts are now required. This review aims at providing a comprehensive overview of the available data on the expression profiles and function of specific miRNAs in BAV aortopathy, evaluating miRNA signatures as potential molecular markers of disease. We also discuss the role of other novel classes of non-coding RNAs, including long non-coding RNAs and circular RNAs, in BAV-associated aortopathy, mainly regarding their possible implementation as diagnostic and prognostic markers.

MiRNA profiling revealed enhanced susceptibility to oxidative stress of endothelial cells from bicuspid aortic valve

AIMS

Calcific aortic valve stenosis (CAVS) is the most frequent manifestation of aortic valve disease and the third leading cause of cardiovascular disease in the Western countries associated with significant morbidity and mortality. An active biological progression involving inflammation and oxidation leading to valve endothelial damage is considered a hallmark of the early stages of valve degeneration. However, tricuspid (TAV) and bicuspid (BAV) aortic valve deterioration are considered to differ only by shear stress. We hypothesized that endothelial cells (EC) derived from BAV and TAV patients have different miRNA expression patterns and thus distinct pathways could lead to endothelial damage in BAV than TAV patients.

METHODS AND RESULTS

We isolated ECs from patients with bicuspid or tricuspid aortic valve, which underwent surgery due to CAVS. MiRNA expression profile by PCR revealed eight upregulated miRNAs between BAV and TAV ECs. Functional analysis identified that BAV ECs presented altered cellular response to oxidative stress and DNA damage stimulus via p53 and alteration in the intrinsic apoptotic signaling pathway. GPX3 and SRXN1 mRNA were express at lower levels in BAV compared to TAV ECs, leading to an increment of DNA double-strand breaks. BAV ECs had a sustained apoptosis activation when compared to TAV ECs. This difference was exacerbated by oxidative stress stimulus leading to a reduced survival rate but completely reverted by miR-328-3p inhibition.

CONCLUSION

The present data showed molecular differences in oxidative stress susceptibility, DNA damage magnitude, and apoptosis induction between ECs derived from BAV and TAV patients.

Gestational diabetes alters microRNA signatures in human feto-placental endothelial cells depending on fetal sex

MicroRNAs (miRNAs), small non-coding RNAs, have emerged as important, epigenetic regulators of endothelial function. Metabolic disturbances such as diabetes alter miRNA expression. In adults, the miRNA transcriptome as well as endothelial function differ between the sexes. Here, we hypothesized that metabolic disturbances associated with gestational diabetes (GDM) alter miRNA signatures in feto-placental endothelial cells (fpEC), dependent on fetal sex. We isolated human primary fpEC after normal and GDM-complicated pregnancies with male and female neonates and screened for differential miRNA expression using next-generation miRNA sequencing. To test for miRNAs commonly regulated in fpEC of female and male progeny, data were stratified for fetal sex and maternal body mass index (BMI). Analyses were also performed separately for female and male fpEC, again accounting for maternal BMI as covariate. Potential biological pathways regulated by the altered set of miRNAs were determined using mirPath software. Maternal GDM altered 26 miRNA signatures when male and female fpEC were analyzed together. Separate analysis of male versus female fpEC revealed 22 GDM affected miRNAs in the females and only 4 in the males, without overlap. Biological functions potentially modulated by the affected miRNAs related to ‘Protein Processing in Endoplasmic Reticulum’ and ‘Proteoglycans in Cancer’. Maternal GDM alters miRNA signatures in fpEC, and biological functions affected by these miRNAs relate to well-known adverse functional consequences of diabetes on endothelium. GDM effects were highly dependent on fetal sex with miRNA signatures in female fpEC being more susceptible to metabolic derangements of GDM than miRNAs in male fpEC.