A Novel Splicing Mutation c.335-1 G > A in the Cardiac Transcription Factor NKX2-5 Leads to Familial Atrial Septal Defect Through miR-19 and PYK2

Cardiomyocyte proliferation and regeneration in congenital heart disease

Despite advances in prenatal screening and a notable decrease in mortality rates, congenital heart disease (CHD) remains the most prevalent congenital disorder in newborns globally. Current therapeutic surgical approaches face challenges due to the significant rise in complications and disabilities. Emerging cardiac regenerative therapies offer promising adjuncts for CHD treatment. One novel avenue involves investigating methods to stimulate cardiomyocyte proliferation. However, the mechanism of altered cardiomyocyte proliferation in CHD is not fully understood, and there are few feasible approaches to stimulate cardiomyocyte cell cycling for optimal healing in CHD patients. In this review, we explore recent progress in understanding genetic and epigenetic mechanisms underlying defective cardiomyocyte proliferation in CHD from development through birth. Targeting cell cycle pathways shows promise for enhancing cardiomyocyte cytokinesis, division, and regeneration to repair heart defects. Advancements in human disease modeling techniques, CRISPR-based genome and epigenome editing, and next-generation sequencing technologies will expedite the exploration of abnormal machinery governing cardiomyocyte differentiation, proliferation, and maturation across diverse genetic backgrounds of CHD. Ongoing studies on screening drugs that regulate cell cycling are poised to translate this nascent technology of enhancing cardiomyocyte proliferation into a new therapeutic paradigm for CHD surgical interventions.

Exploring the role of non-coding RNAs in atrial septal defect pathogenesis: A systematic review

BACKGROUND

Extensive research has recognized the significant roles of non-coding RNAs (ncRNAs) in various cellular pathophysiological processes and their association with diverse diseases, including atrial septal defect (ASD), one of the most prevalent congenital heart diseases. This systematic review aims to explore the intricate involvement and significance of ncRNAs in the pathogenesis and progression of ASD.

METHODS

Four databases (PubMed, Embase, Scopus, and the Web of Science) were searched systematically up to June 19, 2023, with no year restriction. The risk of bias assessment was evaluated using the Newcastle-Ottawa scale.

RESULTS

The present systematic review included thirteen studies with a collective study population of 874 individuals diagnosed with ASD, 21 parents of ASD patients, and 22 pregnant women carrying ASD fetuses. Our analysis revealed evidence linking five long ncRNAs (STX18-AS1, HOTAIR, AA709223, BX478947, and Moshe) and several microRNAs (hsa-miR-19a, hsa-miR-19b, hsa-miR-375, hsa-miR-29c, miR-29, miR-143/145, miR-17-92, miR-106b-25, and miR-503/424, miR-9, miR-30a, miR-196a2, miR-139-5p, hsa-let-7a, hsa-let-7b, and hsa-miR-486) to ASD progression, corresponding to previous studies.

CONCLUSIONS

NcRNAs play a crucial role in unraveling the underlying mechanisms of ASD, contributing to both biomarker discovery and therapeutic advancements. This systematic review sheds light on the mechanisms of action of key ncRNAs involved in ASD progression, providing valuable insights for future research in this field.

Nkx2.5: a crucial regulator of cardiac development, regeneration and diseases

Cardiomyocytes fail to regenerate after birth and respond to mitotic signals through cellular hypertrophy rather than cellular proliferation. Necrotic cardiomyocytes in the infarcted ventricular tissue are eventually replaced by fibroblasts, generating scar tissue. Cardiomyocyte loss causes localized systolic dysfunction. Therefore, achieving the regeneration of cardiomyocytes is of great significance for cardiac function and development. Heart development is a complex biological process. An integral cardiac developmental network plays a decisive role in the regeneration of cardiomyocytes. During this process, genetic epigenetic factors, transcription factors, signaling pathways and small RNAs are involved in regulating the developmental process of the heart. Cardiomyocyte-specific genes largely promote myocardial regeneration, among which the Nkx2.5 transcription factor is one of the earliest markers of cardiac progenitor cells, and the loss or overexpression of Nkx2.5 affects cardiac development and is a promising candidate factor. Nkx2.5 affects the development and function of the heart through its multiple functional domains. However, until now, the specific mechanism of Nkx2.5 in cardiac development and regeneration is not been fully understood. Therefore, this article will review the molecular structure, function and interaction regulation of Nkx2.5 to provide a new direction for cardiac development and the treatment of heart regeneration.