Identification and characterization of a novel ELN mutation in congenital heart disease with pulmonary artery stenosis

Effect of elastin on abnormal proliferation of pulmonary artery smooth muscle cells at an early stage of hypoxic exposure

Elastin (Eln) is an extracellular matrix protein implicated in the proliferation of vascular smooth muscle cells. However, its potential role in hypoxic pulmonary hypertension (HPH) remains uncertain. This study is the first to demonstrate that elastin can promote the proliferation of mouse pulmonary artery smooth muscle cells (mPASMCs) and that hypoxia significantly induces Eln expression in cultured mPASMCs, thereby participating in the cell cycle. Interference with Eln expression via siRNA led to the downregulation of PCNA, Cyclin A, and Cyclin D, thus, the hypoxia-induced proliferation of mPASMCs was reversed. Furthermore, our study demonstrated that the hypoxia-induced expression of Eln and the proliferation of mPASMCs are associated with the proliferation-related phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. In conclusion, these data suggest that Eln is a key regulatory factor in mPASMCs proliferation, potentially elucidating the mechanism underlying hypoxia-induced mPASMCs proliferation. This finding may offer valuable insights for the study of hypoxic pulmonary hypertension.

AAV9-mediated SMN gene therapy rescues cardiac desmin but not lamin A/C and elastin dysregulation in Smn2B/- spinal muscular atrophy mice

Structural, functional and molecular cardiac defects have been reported in spinal muscular atrophy (SMA) patients and mouse models. Previous quantitative proteomics analyses demonstrated widespread molecular defects in the severe Taiwanese SMA mouse model. Whether such changes are conserved across different mouse models, including less severe forms of the disease, has yet to be established. Here, using the same high-resolution proteomics approach in the less-severe Smn2B/- SMA mouse model, 277 proteins were found to be differentially abundant at a symptomatic timepoint (post-natal day (P) 18), 50 of which were similarly dysregulated in severe Taiwanese SMA mice. Bioinformatics analysis linked many of the differentially abundant proteins to cardiovascular development and function, with intermediate filaments highlighted as an enriched cellular compartment in both datasets. Lamin A/C was increased in the cardiac tissue, whereas another intermediate filament protein, desmin, was reduced. The extracellular matrix (ECM) protein, elastin, was also robustly decreased in the heart of Smn2B/- mice. AAV9-SMN1-mediated gene therapy rectified low levels of survival motor neuron protein and restored desmin levels in heart tissues of Smn2B/- mice. In contrast, AAV9-SMN1 therapy failed to correct lamin A/C or elastin levels. Intermediate filament proteins and the ECM have key roles in cardiac function and their dysregulation may explain cardiac impairment in SMA, especially since mutations in genes encoding these proteins cause other diseases with cardiac aberration. Cardiac pathology may need to be considered in the long-term care of SMA patients, as it is unclear whether currently available treatments can fully rescue peripheral pathology in SMA.

Three-dimensional molecular architecture of mouse organogenesis

Mammalian embryos exhibit sophisticated cellular patterning that is intricately orchestrated at both molecular and cellular level. It has recently become apparent that cells within the animal body display significant heterogeneity, both in terms of their cellular properties and spatial distributions. However, current spatial transcriptomic profiling either lacks three-dimensional representation or is limited in its ability to capture the complexity of embryonic tissues and organs. Here, we present a spatial transcriptomic atlas of all major organs at embryonic day 13.5 in the mouse embryo, and provide a three-dimensional rendering of molecular regulation for embryonic patterning with stacked sections. By integrating the spatial atlas with corresponding single-cell transcriptomic data, we offer a detailed molecular annotation of the dynamic nature of organ development, spatial cellular interactions, embryonic axes, and divergence of cell fates that underlie mammalian development, which would pave the way for precise organ engineering and stem cell-based regenerative medicine.

Sudden Cardiac Arrest During a Sedated Cardiac Magnetic Resonance Study in a Nonsyndromic Child with Evolving Supravalvar Aortic Stenosis Due to Familial ELN Mutation

Supravalvar aortic stenosis (SVAS) is a less common but clinically important form of left ventricular outflow tract obstruction, and commonly associated with Williams syndrome (WS). SVAS outside of WS may also occur sporadically or in a familial form, often with identifiable mutations in the elastin (ELN) gene. While risk of sudden cardiac death in patients with SVAS has been extensively described in the context of WS, less is known about risk in patients with isolated SVAS. We report a case of a nonsyndromic two-year-old boy with evolving manifestations of SVAS who developed sudden cardiac arrest and death during a sedated cardiac magnetic resonance imaging study. A strong family history of SVAS was present and targeted genetic testing identified an ELN gene mutation in the boy's affected father and other paternal relatives. We review risk factors found in the literature for SCA in SVAS patients and utilize this case to raise awareness of the risk of cardiac events in these individuals even in the absence of WS or severe disease. This case also underscores the importance of genetic testing, including targeted panels specifically looking for ELN gene mutations, in all patients with SVAS even in the absence of phenotypic concerns for WS or other genetic syndromes.

Efficacy and Safety of Minimally Invasive Transcatheter Closure of Congenital Heart Disease under the Guidance of Transesophageal Ultrasound: A Randomized Controlled Trial

Objective

To investigate the efficacy of minimally invasive transcatheter closure of congenital heart disease (CHD) under the guidance of transesophageal ultrasound.

Methods

A total of 100 patients with CHD treated in our hospital from February 2019 to April 2020 were enrolled in the group. The patients were randomly divided into control group and research group. The control group received minimally invasive transcatheter closure under the guidance of X-ray, and the research group received minimally invasive transcatheter closure under the guidance of transesophageal ultrasound. The operative results, the intraoperative- and postoperative-related indexes, and the incidence of early postoperative complications and follow-up results were compared.

Results

First of all, we compared the results of the two groups: 48 cases of success, 2 cases of difficulty in the research group, 35 cases of success, 11 cases of difficulty, and 4 cases of failure in the control group. The success rate in the research group was higher than that in the control group (P < 0.05). Secondly, we compare the relevant indicators in the process of operation. The operation time, cardiopulmonary bypass time, upper and lower cavity obstruction time, and blood transfusion volume in the research group were lower than those in the control group (P < 0.05). In terms of postoperative-related indexes, the ventilator-assisted time, 24 h postoperative drainage, ICU time, and postoperative hospital stay in the research group were all lower than those in the control group (P < 0.05). The incidence of early postoperative complications in the research group was significantly lower than that in the control group such as secondary pleural hemostasis, pulmonary infection, pleural effusion, subcutaneous emphysema, poor incision healing, phrenic nerve loss, and right lower limb numbness (P < 0.05). All patients were followed up for 6 months, and the cardiac function of both groups returned to normal. There was no significant difference in the incidence of postoperative residual shunt and new tricuspid regurgitation. There was no significant difference in the data (P > 0.05). Considering abnormal ECG events, the incidence of abnormal ECG events (complete right bundle branch block, incomplete right bundle branch block, second- and third-degree block, left anterior branch block) in the research group was significantly lower than that in the control group (P < 0.05).

Conclusion

Minimally invasive transcatheter closure of CHD under the guidance of transesophageal ultrasound has the advantages of less trauma, less blood loss, short hospital stay, simple operation, less postoperative complications, and remarkable therapeutic effect. Minimally invasive transcatheter closure under the guidance of transesophageal ultrasound has the advantage of adapting to a wide range of syndromes and can be used for the closure of CHD in children. According to different types of CHD, registering the corresponding occlusive pathway can improve the success rate of operation. Through postoperative reexamination and regular follow-up, it is proved that minimally invasive transcatheter closure under the guidance of transesophageal ultrasound is safe, effective, and feasible.