Cardio-cephalic neural crest syndrome: A novel hypothesis of vascular neurocristopathy

Systematic review of cardiovascular neurocristopathy-contemporary insights and future perspectives

Introduction

Neural crest cells (NCCs) are multipotent and are attributed to the combination of complex multimodal gene regulatory mechanisms. Cardiac neural crest (CNC) cells, originating from the dorsal neural tube, are pivotal architects of the cardio-neuro-vascular domain, which orchestrates the embryogenesis of critical cardiac and vascular structures. Remarkably, while the scientific community compiled a comprehensive inventory of neural crest derivatives by the early 1980s, our understanding of the CNC's role in various cardiovascular disease processes still needs to be explored. This review delves into the differentiation of NCC, specifically the CNC cells, and explores the diverse facets of non-syndromic cardiovascular neurocristopathies.

Methods

A systematic review was conducted as per the PRISMA Statement. Three prominent databases, PubMed, Scopus, and Embase, were searched, which yielded 1,840 studies. We excluded 1,796 studies, and the final selection of 44 studies formed the basis of this comprehensive review.

Results

Neurocristopathies are a group of genetic disorders that affect the development of cells derived from the NC. Cardiovascular neurocristopathy, i.e., cardiopathy and vasculopathy, associated with the NCC could occur in the form of (1) cardiac septation disorders, mainly the aortico-pulmonary septum; (2) great vessels and vascular disorders; (3) myocardial dysfunction; and (4) a combination of all three phenotypes. This could result from abnormalities in NCC migration, differentiation, or proliferation leading to structural abnormalities and are attributed to genetic, familial, sporadic or acquired causes.

Discussion

Phenotypic characteristics of cardiovascular neurocristopathies, such as bicuspid aortic valve and thoracic aortic aneurysm, share a common embryonic origin and are surprisingly prevalent in the general population, necessitating further research to identify the underlying pathogenic and genetic factors responsible for these cardiac anomalies. Such discoveries are essential for enhancing diagnostic screening and refining therapeutic interventions, ultimately improving the lives of individuals affected by these conditions.

Emerging insights into cephalic neural crest disorders: A single center experience

Objectives

Neural crest cells (NCCs) are transient structures in the fetal life in vertebrates, which develop at the junctional site of the non-neural and neural ectoderm, sharing a common developmental origin for diverse diseases. After Epithelio-mesenchymal (EMT) of the NCCs within the neural tube, delamination of NCCs occurs. After delamination, the transformation of these cells into various cell lineages produces melanocytes, bones, and cartilage of the skull, cells of the enteric and peripheral nervous system. After the conversion, these cells migrate into various locations of the entire body according to the cell lineage. Abnormalities in neural crest (NC) formation and migration result in various malformations and tumors, known as neurocristopathy.

Material and Methods

Herein, this case series describes a single-center experience in cephalic NC disorders over the past 3 years, including 17 cases of varying composition (i.e., vascular, dysgenetic, mixed, and neoplastic forms) involving the brain and occasionally skin, eyes, and face of the patients.

Results

In our study of 17 patients with cephalic NC disease, 6 (35.3%) patients had vascular form, 5 (29.4%) had dysgenetic form, 4 (23.5%) had mixed form, and 2 (11.7%) had neoplastic form. Brain involvement in the form of vascular or parenchyma or both vascular and parenchymal was seen in all of our patients (100%), skin in 6 (35.3%) patients, eye in 2 (11.7%), and face in 1 (5.9%) patient. Treatment was planned according to the various manifestations of the disease.

Conclusion

Neural crest diseases (NCDs) are a rare and under-recognized group of disorders in the literature and may have been under-reported due to a lack of awareness regarding the same. More such reporting may increase the repertoire of these rare disorders such that clinicians can have a high degree of suspicion leading to early detection and timely counseling and also improve preventive strategies and help in developing new drugs for these disorders or prevent them.

Spatially resolved transcriptomics for evaluation of intracranial vessels in a rabbit model: Proof of concept

BACKGROUND

Better understanding of vessel biology and vascular pathophysiology is needed to improve understanding of cerebrovascular disorders. Tissue from diseased vessels can offer the best data. Rabbit models can be effective for studying intracranial vessels, filling gaps resulting from difficulties acquiring human tissue. Spatially-resolved transcriptomics (SRT) in particular hold promise for studying such models as they build on RNA sequencing methods, augmenting such data with histopathology.

METHODS

Rabbit brains with intact arteries were flash frozen, cryosectioned, and stained with H&E to confirm adequate inclusion of intracranial vessels before proceeding with tissue optimization and gene expression analysis using the Visium SRT platform. SRT results were analyzed with k-means clustering analysis, and differential gene expression was examined, comparing arteries to veins.

RESULTS

Cryosections were successfully mounted on Visium proprietary slides. Quality control thresholds were met. Optimum permeabilization was determined to be 24 min for the tissue optimization step. In analysis of SRT data, k-means clustering distinguished vascular tissue from parenchyma. When comparing gene expression traits, the most differentially expressed genes were those found in smooth muscle cells. These genes were more commonly expressed in arteries compared to veins.

CONCLUSIONS

Intracranial vessels from model rabbits can be processed and analyzed with the Visium SRT platform. Face validity is found in the ability of SRT data to distinguish vessels from parenchymal tissue and differential expression analysis accurately distinguishing arteries from veins. SRT should be considered for future animal model investigations into cerebrovascular diseases.

Clinical and neuroimaging features of a familial pathogenic ACTA2 variant as a model of a vascular neurocristopathy

The clinical and neuroimaging findings of a family with a variant ACTA2 gene (c351C > G), presenting with smooth muscle dysfunction in structures of neural crest derivation, are discussed. The combination of aortic abnormalities, patent ductus arteriosus, congenital mydriasis and distinctive cerebrovascular and brain morphological abnormalities characterise this disorder. Two sisters, heterozygous for the variant, and their mother, a mosaic, are presented. Brain parenchymal changes are detailed for the first time in a non-Arg179His variant. Radiological features of the petrous canal and external carotid are highlighted. We explore the potential underlying biological and embryological mechanisms.

Ophthalmic involvement in PHACES syndrome: prevalence, spectrum of anomalies, and outcomes

PURPOSE

To highlight prevalence, spectrum of anomalies, and outcome of ophthalmic involvement in PHACES syndrome (posterior fossa malformations, infantile hemangiomas, arterial, cardiac, eye, and sternal anomalies).

METHODS

A retrospective, noncomparative, single-institution observational case series of children with PHACES was conducted from 2000 to 2019. Data on ocular presentations, interventions and visual outcomes were collected. Primary outcome measures were the frequency and spectrum of ocular involvement. Secondary outcomes were final visual acuity, long-term ocular sequelae, and frequency of surgical interventions.

RESULTS

A total of 43 infants had PHACES, of whom 29 (67%) had periocular infantile facial hemangiomas (IFH) and 6 (14%) had primary ocular anomalies that were always ipsilateral to the IFH. Five patients (12%) met ocular PHACES-specific diagnostic criteria, including optic nerve (3), retinal vascular (1) and lenticular (2) anomalies. Non-PHACES-specific abnormalities were Peters anomaly (1), persistent pupillary membranes (2), dysmorphic optic nerves (1), and iris/choroidal hemangiomas (2). IFH-related periocular abnormalities were frequent: ptosis (29), proptosis (9), strabismus (6). Surgery was required in 8 of the 29 children: (strabismus [6], entropion [2], ptosis [2], and optical iridectomy [1]), all of whom had orbital/conjunctival hemangioma (P = 0.03). Final visual acuity (follow-up, 8.7 years) ranged between 20/20 and 20/80 in 26 of 29 patients. All patients with visual acuity worse than 20/200 (3/29 [10%]) had structural anomalies.

CONCLUSIONS

Two-thirds of infants with PHACES have periocular IFH causing vision compromising complications of amblyopia and strabismus. Structural ocular anomalies exist in 1 of 7 patients and are always ipsilateral to the IFH. Long-term ophthalmic monitoring and management is required, and the majority of patients obtain good visual outcomes.

Cephalic/cardiac neural crest cell and moyamoya disease

BACKGROUND

The neural crest is a transient structure present in early embryogenesis. Cephalic neural crest cells migrate into the pharyngeal arches and the frontonasal process that becomes the forehead and midfacial structures. They also contribute to forming the media of the arteries of the circle of Willis and their branches. The cardiac neural crest produces vascular smooth muscle cells in the ascending aorta, cardiac septum and coronary arteries.

METHODS

In this review, we evaluate the role of the neural crest in moyamoya disease and the pathological implications from the concurrence of moyamoya disease and cardiovascular diseases from the point of view of neural crest cell distributions.

RESULTS

Midline craniofacial and central nervous system anomalies with eye anomalies, morning glory disc anomaly in patients with moyamoya disease can both be explained as a subtype of cephalic neurocristopathy. Further, the association between moyamoya disease and cardiac manifestations (congenital cardiac defects and coronary artery disease) have also been reported. Both the cephalic neural crest and cardiac neural crest contribute to these concurrent arterial diseases, as cardio-cephalic neurocristopathy.

CONCLUSION

The concept of cephalic/cardio-cephalic neurocristopathy provides a new perspective to understanding the underlying aetiological associations and to developing future therapeutic approaches for concomitant moyamoya disease and cardiovascular diseases.

RNF213 c.14576G>A Is Associated with Intracranial Internal Carotid Artery Saccular Aneurysms

A mutation in RNF213 (c.14576G>A), a gene associated with moyamoya disease (>80%), plays a role in terminal internal carotid artery (ICA) stenosis (>15%) (ICS). Studies on RNF213 and cerebral aneurysms (AN), which did not focus on the site of origin or morphology, could not elucidate the relationship between the two. However, a report suggested a relationship between RNF213 and AN in French-Canadians. Here, we investigated the relationship between ICA saccular aneurysm (ICA-AN) and RNF213. We analyzed RNF213 expression in subjects with ICA-AN and atherosclerotic ICS. Cases with a family history of moyamoya disease were excluded. AN smaller than 4 mm were confirmed as AN only by surgical or angiographic findings. RNF213 was detected in 12.2% of patients with ICA-AN and 13.6% of patients with ICS; patients with ICA-AN and ICS had a similar risk of RNF213 mutation expression (odds ratio, 0.884; 95% confidence interval, 0.199-3.91; p = 0.871). The relationship between ICA-AN and RNF213 (c.14576G>A) was not correlated with the location of the ICA and bifurcation, presence of rupture, or multiplicity. When the etiology and location of AN were more restricted, the incidence of RNF213 mutations in ICA-AN was higher than that reported in previous studies. Our results suggest that strict maternal vessel selection and pathological selection of AN morphology may reveal an association between genetic mutations and ICA-AN development. The results of this study may form a basis for further research on systemic vascular diseases, in which the RNF213 (c.14576G>A) mutation has been implicated.

Rare Neurovascular Diseases in Korea: Classification and Related Genetic Variants

Rare neurovascular diseases (RNVDs) have not been well-recognized in Korea. They involve the central nervous system and greatly affect the patients' lives. However, these diseases are difficult to diagnose and treat due to their rarity and incurability. We established a list of RNVDs by referring to the previous literature and databases worldwide to better understand the diseases and their current management status. We categorized 68 RNVDs based on their pathophysiology and clinical manifestations and estimated the prevalence of each disease in Korea. Recent advances in genetic, molecular, and developmental research have enabled further understanding of these RNVDs. Herein, we review each disease, while considering its classification based on updated pathologic mechanisms, and discuss the management status of RNVD in Korea.

RNF213 p.R4810K (c.14429G > A) Variant Determines Anatomical Variations of the Circle of Willis in Cerebrovascular Disease

Introduction

Dysregulation of the RING finger protein 213 (RNF213) gene impairs vascular formation in experimental animal models. In addition, vascular abnormalities in the circle of Willis are associated with cerebrovascular disease. Here, we evaluated the relationship between the East Asian founder variant RNF213 p.R4810K and consequent anatomical variations in the circle of Willis in cerebrovascular disease.

Patients and Methods

The present study is an observational cross-sectional study. It included patients with acute anterior circulation non-cardioembolic stroke admitted to our institution within 7 days of symptom onset or last-known-well from 2011 to 2019, and those who participated in the National Cerebral and Cardiovascular Center Biobank. We compared anatomical variations of the vessels constituting the circle of Willis between RNF213 p.R4810K (c.14429G > A) variant carriers and non-carriers using magnetic resonance angiography and assessed the association between the variants and the presence of the vessels constituting the circle of Willis. Patients with moyamoya disease were excluded.

Results

Four hundred eighty-one patients [146 women (30%); median age 70 years; median baseline National Institutes of Health Stroke Scale score 5] were analyzed. The RNF213 p.R4810K variant carriers (n = 25) were more likely to have both posterior communicating arteries (PComAs) than the variant non-carriers (n = 456) (56% vs. 13%, P < 0.01). Furthermore, variant carriers were less likely to have an anterior communicating artery (AComA) than non-carriers (68% vs. 84%, P = 0.04). In a multivariate logistic regression analysis, the association of RNF213 p.R4810K variant carriers with the presence of both PComAs and the absence of AComA remained significant.

Conclusion

Our findings suggest that the RNF213 p.R4810K variant is an important factor in determining anatomical variations in the circle of Willis.

Introduction to phacomatoses (neurocutaneous disorders) in childhood

The Dutch ophthalmologist, Jan van der Hoeve, first introduced the terms phakoma/phakomata (from the old Greek word "ϕαχοσ" = lentil, spot, lens-shaped) to define similar retinal lesions recorded in tuberous sclerosis (1920) and in neurofibromatosis (1923). He later applied this concept: (a) to similar lesions in other organs (e.g. brain, heart and kidneys) (1932) and (b) to other disorders (i.e. von Hippel-Lindau disease and Sturge-Weber syndrome) (1933), and coined the term phakomatoses. At the same time, the American neurologist Paul Ivan Yakovlev and psychiatrist Riley H. Guthrie (1931) established the key role of nervous systems and skin manifestations in these conditions and proposed to name them neurocutaneous syndromes (or ectodermoses, to explain the pathogenesis). The Belgian pathologist, Ludo van Bogaert, came to similar conclusions (1935), but used the term neuro-ectodermal dysplasias. In the 1980s, the American paediatric neurologist Manuel R. Gomez introduced the concept of "hamartia/hamartoma" instead of phakoma/phakomata. "Genodermatoses" and "neurocristopathies" were alternative terms still used to define these conditions. Nowadays, however, the most acclaimed terms are "phacomatoses" and "neurocutaneous disorders", which are used interchangeably. Phacomatoses are a heterogeneous group of conditions (mainly) affecting the skin (with congenital pigmentary/vascular abnormalities and/or tumours), the central and peripheral nervous system (with congenital abnormalities and/or tumours) and the eye (with variable abnormalities). Manifestations may involve many other organs or systems including the heart, vessels, lungs, kidneys and bones. Pathogenically, they are explained by interplays between intra- and extra-neuronal signalling pathways encompassing receptor-to-protein and protein-to-protein cascades involving RAS, MAPK/MEK, ERK, mTOR, RHOA, PI3K/AKT, PTEN, GNAQ and GNA11 pathways, which shed light also to phenotypic variability and overlapping. We hereby review the history, classification, genomics, clinical manifestations, diagnostic criteria, surveillance protocols and therapies, in phacomatoses: (1) predisposing to development of tumours (i.e. the neurofibromatoses and allelic/similar disorders and schwannomatosis; tuberous sclerosis complex; Gorlin-Goltz and Lhermitte-Duclos-Cowden syndromes); (2) with vascular malformations (i.e. Sturge-Weber and Klippel-Trenaunay syndromes; megalencephaly/microcephaly-capillary malformation syndromes; CLOVES, Wyburn-Mason and mixed vascular nevus syndromes; blue rubber bleb nevus syndrome; hereditary haemorrhagic telangiectasia); (3) with vascular tumours (von Hippel-Lindau disease; PHACE(S)); (4) with pigmentary/connective tissue mosaicism (incontinentia pigmenti; pigmentary/Ito mosaicism; mTOR-related megalencephaly/focal cortical dysplasia/pigmentary mosaicism; RHOA-related ectodermal dysplasia; neurocutaneous melanocytosis; epidermal/papular spilus/Becker nevi syndromes; PENS and LEOPARD syndromes; encephalocraniocutaneous lipomatosis; lipoid proteinosis); (5) with dermal dysplasia (cerebellotrigeminal dermal dysplasia); and (6) with twin spotting or similar phenomena (phacomatosis pigmentovascularis and pigmentokeratotica; and cutis tricolor).

New Concepts in the Development and Malformation of the Arterial Valves

Although in many ways the arterial and atrioventricular valves are similar, both being derived for the most part from endocardial cushions, we now know that the arterial valves and their surrounding structures are uniquely dependent on progenitors from both the second heart field (SHF) and neural crest cells (NCC). Here, we will review aspects of arterial valve development, highlighting how our appreciation of NCC and the discovery of the SHF have altered our developmental models. We will highlight areas of research that have been particularly instructive for understanding how the leaflets form and remodel, as well as those with limited or conflicting results. With this background, we will explore how this developmental knowledge can help us to understand human valve malformations, particularly those of the bicuspid aortic valve (BAV). Controversies and the current state of valve genomics will be indicated.

Cardiac manifestations in a western moyamoya disease population: a single-center descriptive study and review

An embryological association between moyamoya disease (MMD) and cardiac manifestations has been proposed. Data up to this point remains anecdotal, and the prevalence of cardiac manifestations in a western MMD population is uncertain. The objective of this study was to determine the prevalence of cardiac manifestations including coronary artery disease (CAD) and congenital cardiac defects in a mostly Caucasian population of MMD patients and review prior reports of such cases. Medical records of MMD patients who presented to our institution between 1990 and 2019 were retrospectively reviewed for the presence of various congenital cardiac malformations and concomitant CAD. The prevalence of congenital cardiac defects and CAD was determined. A literature search for prior cases of MMD with concomitant cardiac manifestations was performed. A total of 181 MMD patients were included in our analysis, 139 (76.8%) of whom were Caucasian. Ten patients had cardiac manifestations (5.5%). There were six total MMD patients with congenital cardiac defects (3.3%). All patients with congenital defects were diagnosed in childhood. The prevalence of congenital defects in MMD was slightly higher than the general population as reported previously (0.8-1.2%). Four MMD patients had CAD (2.2%). The mean age of patients with CAD was 41.0 years (SD = 12.3, range = 33-59) in our series and 33.1 years (SD = 15.0) in a review of prior reports. These mean ages of CAD are in contrast to the 7th and 8th decades of lifein the general population as indicated by prior studies. Our findings support an association between MMD and cardiac manifestations. Further investigation is warranted in order to further characterize this potential relationship and shed light on a possible cardio-cephalic neural crest syndrome.