LncRNA AC105942.1 Downregulates hnRNPA2/B1 to Attenuate Vascular Smooth Muscle Cells Proliferation

Non-coding RNAs to treat vascular smooth muscle cell dysfunction

Vascular smooth muscle cell (vSMC) dysfunction is a critical contributor to cardiovascular diseases, including atherosclerosis, restenosis and vein graft failure. Recent advances have unveiled a fascinating range of non-coding RNAs (ncRNAs) that play a pivotal role in regulating vSMC function. This review aims to provide an in-depth analysis of the mechanisms underlying vSMC dysfunction and the therapeutic potential of various ncRNAs in mitigating this dysfunction, either preventing or reversing it. We explore the intricate interplay of microRNAs, long-non-coding RNAs and circular RNAs, shedding light on their roles in regulating key signalling pathways associated with vSMC dysfunction. We also discuss the prospects and challenges associated with developing ncRNA-based therapies for this prevalent type of cardiovascular pathology.

Proteomics Studies Suggest That Nitric Oxide Donor Furoxans Inhibit In Vitro Vascular Smooth Muscle Cell Proliferation by Nitric Oxide-Independent Mechanisms

Physiologically, smooth muscle cells (SMC) and nitric oxide (NO) produced by endothelial cells strictly cooperate to maintain vasal homeostasis. In atherosclerosis, where this equilibrium is altered, molecules providing exogenous NO and able to inhibit SMC proliferation may represent valuable antiatherosclerotic agents. Searching for dual antiproliferative and NO-donor molecules, we found that furoxans significantly decreased SMC proliferation in vitro, albeit with different potencies. We therefore assessed whether this property is dependent on their thiol-induced ring opening. Indeed, while furazans (analogues unable to release NO) are not effective, furoxans' inhibitory potency parallels with the electron-attractor capacity of the group in 3 of the ring, making this effect tunable. To demonstrate whether their specific block on G1-S phase could be NO-dependent, we supplemented SMCs with furoxans and inhibitors of GMP- and/or of the polyamine pathway, which regulate NO-induced SMC proliferation, but they failed in preventing the antiproliferative effect. To find the real mechanism of this property, our proteomics studies revealed that eleven cellular proteins (with SUMO1 being central) and networks involved in cell homeostasis/proliferation are modulated by furoxans, probably by interaction with adducts generated after degradation. Altogether, thanks to their dual effect and pharmacological flexibility, furoxans may be evaluated in the future as antiatherosclerotic molecules.

RNA-binding proteins in vascular inflammation and atherosclerosis

Atherosclerotic cardiovascular disease (ASCVD) remains the major cause of premature death and disability worldwide, even when patients with an established manifestation of atherosclerotic heart disease are optimally treated according to the clinical guidelines. Apart from the epigenetic control of transcription of the genetic information to messenger RNAs (mRNAs), gene expression is tightly controlled at the post-transcriptional level before the initiation of translation. Although mRNAs are traditionally perceived as the messenger molecules that bring genetic information from the nuclear DNA to the cytoplasmic ribosomes for protein synthesis, emerging evidence suggests that processes controlling RNA metabolism, driven by RNA-binding proteins (RBPs), affect cellular function in health and disease. Over the recent years, vascular endothelial cell, smooth muscle cell and immune cell RBPs have emerged as key co- or post-transcriptional regulators of several genes related to vascular inflammation and atherosclerosis. In this review, we provide an overview of cell-specific function of RNA-binding proteins involved in all stages of ASCVD and how this knowledge may be used for the development of novel precision medicine therapeutics.

Long non-coding RNAs: The growth controller of vascular smooth muscle cells in cardiovascular diseases

The active proliferation and migration of vascular smooth muscle cells supports the healing of vessel damage while their abnormal aggression or destitution contribute to the aberrant intima-medial structure and function in various cardiovascular diseases, so the understanding of the proliferation disorders of vascular smooth muscle cell and the related mechanism is the basis of effective intervention and control for cardiovascular diseases. Recently, long non-coding RNAs have stood out as upstream switchers for multiple proliferative signaling pathways and molecules, and many of them have been shown to conduce to the dysregulated proliferation and apoptosis of vascular smooth muscle cells under various pathogenic stimuli. This article discusses the long non-coding RNAs disclosed and linked to atherosclerosis, pulmonary hypertension, and aneurysms, and focuses upon their modulation of vascular smooth muscle cell population affecting three deadly cardiovascular diseases.

Nucleolin Regulates Pulmonary Artery Smooth Muscle Cell Proliferation under Hypoxia by Modulating miRNA Expression

Hypoxia induces the abnormal proliferation of vascular smooth muscle cells (VSMCs), resulting in the pathogenesis of various vascular diseases. RNA-binding proteins (RBPs) are involved in a wide range of biological processes, including cell proliferation and responses to hypoxia. In this study, we observed that the RBP nucleolin (NCL) was downregulated by histone deacetylation in response to hypoxia. We evaluated its regulatory effects on miRNA expression under hypoxic conditions in pulmonary artery smooth muscle cells (PASMCs). miRNAs associated with NCL were assessed using RNA immunoprecipitation in PASMCs and small RNA sequencing. The expression of a set of miRNAs was increased by NCL but reduced by hypoxia-induced downregulation of NCL. The downregulation of miR-24-3p and miR-409-3p promoted PASMC proliferation under hypoxic conditions. These results clearly demonstrate the significance of NCL-miRNA interactions in the regulation of hypoxia-induced PASMC proliferation and provide insight into the therapeutic value of RBPs for vascular diseases.

HNRNPA2B1: RNA-Binding Protein That Orchestrates Smooth Muscle Cell Phenotype in Pulmonary Arterial Hypertension

BACKGROUND

RNA-binding proteins are master orchestrators of gene expression regulation. They regulate hundreds of transcripts at once by recognizing specific motifs. Thus, characterizing RNA-binding proteins targets is critical to harvest their full therapeutic potential. However, such investigation has often been restricted to a few RNA-binding protein targets, limiting our understanding of their function. In cancer, the RNA-binding protein HNRNPA2B1 (heterogeneous nuclear ribonucleoprotein A2B1; A2B1) promotes the pro-proliferative/anti-apoptotic phenotype. The same phenotype in pulmonary arterial smooth muscle cells (PASMCs) is responsible for the development of pulmonary arterial hypertension (PAH). However, A2B1 function has never been investigated in PAH.

METHOD

Through the integration of computational and experimental biology, the authors investigated the role of A2B1 in human PAH-PASMC. Bioinformatics and RNA sequencing allowed them to investigate the transcriptome-wide function of A2B1, and RNA immunoprecipitation and A2B1 silencing experiments allowed them to decipher the intricate molecular mechanism at play. In addition, they performed a preclinical trial in the monocrotaline-induced pulmonary hypertension rat model to investigate the relevance of A2B1 inhibition in mitigating pulmonary hypertension severity.

RESULTS

They found that A2B1 expression and its nuclear localization are increased in human PAH-PASMC. Using bioinformatics, they identified 3 known motifs of A2B1 and all mRNAs carrying them. In PAH-PASMC, they demonstrated the complementary nonredundant function of A2B1 motifs because all motifs are implicated in different aspects of the cell cycle. In addition, they showed that in PAH-PASMC, A2B1 promotes the expression of its targets. A2B1 silencing in PAH-PASMC led to a decrease of all tested mRNAs carrying an A2B1 motif and a concomitant decrease in proliferation and resistance to apoptosis. Last, in vivo A2B1 inhibition in the lungs rescued pulmonary hypertension in rats.

CONCLUSIONS

Through the integration of computational and experimental biology, the study revealed the role of A2B1 as a master orchestrator of the PAH-PASMC phenotype and its relevance as a therapeutic target in PAH.

Long non-coding RNAs: Modulators of phenotypic transformation in vascular smooth muscle cells

Long non-coding RNA (lncRNAs) are longer than 200 nucleotides and cannot encode proteins but can regulate the expression of genes through epigenetic, transcriptional, and post-transcriptional modifications. The pathophysiology of smooth muscle cells can lead to many vascular diseases, and studies have shown that lncRNAs can regulate the phenotypic conversion of smooth muscle cells so that smooth muscle cells proliferate, migrate, and undergo apoptosis, thereby affecting the development and prognosis of vascular diseases. This review discusses the molecular mechanisms of lncRNA as a signal, bait, stent, guide, and other functions to regulate the phenotypic conversion of vascular smooth muscle cells, and summarizes the role of lncRNAs in regulating vascular smooth muscle cells in atherosclerosis, hypertension, aortic dissection, vascular restenosis, and aneurysms, providing new ideas for the diagnosis and treatment of vascular diseases.

Comprehensive Analysis of circRNA-miRNA-mRNA Regulatory Network and Novel Potential Biomarkers in Acute Myocardial Infarction

Background

Circular RNA (circRNA) plays an important role in the regulation of gene expression and the occurrence of human diseases. However, studies on the role of circRNA in acute myocardial infarction (AMI) are limited. This study was performed to explore novel circRNA-related regulatory networks in AMI, aiming to better understand the molecular mechanism of circRNAs involvement in AMI and provide basis for further scientific research and clinical decision-making.

Methods

The AMI-related microarray datasets GSE160717 (circRNA), GSE31568 (miRNA), GSE61741 (miRNA), and GSE24519 (mRNA) were obtained from the Gene Expression Omnibus (GEO) database. After differential expression analysis, the regulatory relationships between these DERNAs were identified by online databases circBank, circInteractome, miRDB, miRWalk, Targetscan, and then two circRNA-miRNA-mRNA regulatory networks were constructed. Differentially expressed genes (DEGs) in this network were selected followed by enrichment analysis and protein–protein interaction (PPI) analysis. Hub genes were identified using Cytohubba plug-in of Cytoscape software. Hub genes and hub gene-related miRNAs were used for receiver operating characteristic curve (ROC) analysis to identify potential biomarkers. The relative expression levels of these biomarkers were further assessed by GSE31568 (miRNA) and GSE66360 (mRNA). Finally, on the basis of the above analysis, myocardial hypoxia model was constructed to verify the expression of Hub genes and related circRNAs.

Results

A total of 83 DEcircRNAs, 109 CoDEmiRNAs and 1204 DEGs were significantly differentially expressed in these datasets. The up-regulated circRNAs and down-regulated circRNAs were used to construct a circRNA-miRNA-mRNA regulatory network respectively. These circRNA-related DEGs were mainly enriched in the terms of “FOXO signaling pathway,” “T cell receptor signaling pathway,” “MAPK signaling pathway,” “Insulin resistance,” “cAMP signaling pathway,” and “mTOR signaling pathway.” The top 10 hub genes ATP2B2, KCNA1, GRIN2A, SCN2B, GPM6A, CACNA1E, HDAC2, SRSF1, ANK2, and HNRNPA2B1 were identified from the PPI network. Hub genes GPM6A, SRSF1, ANK2 and hub gene-related circRNAs hsa_circ_0023461, hsa_circ_0004561, hsa_circ_0001147, hsa_circ_0004771, hsa_circ_0061276, and hsa_circ_0045519 were identified as potential biomarkers in AMI.

Conclusion

In this study, the potential circRNAs associated with AMI were identified and two circRNA-miRNA-mRNA regulatory networks were constructed. This study explored the mechanism of circRNA involvement in AMI and provided new clues for the selection of new diagnostic markers and therapeutic targets for AMI.

10-Hydroxydec-2-Enoic Acid Reduces Hydroxyl Free Radical-Induced Damage to Vascular Smooth Muscle Cells by Rescuing Protein and Energy Metabolism

10-Hydroxydec-2-enoic acid (10-HDA), an unsaturated hydroxyl fatty acid from the natural food royal jelly, can protect against cell and tissue damage, yet the underlying mechanisms are still unexplored. We hypothesized that the neutralization of the hydroxyl free radical (•OH), the most reactive oxygen species, is an important factor underlying the cytoprotective effect of 10-HDA. In this study, we found that the •OH scavenging rate by 10-HDA (2%, g/ml) was more than 20%, which was achieved through multiple-step oxidization of the -OH group and C=C bond of 10-HDA. Moreover, 10-HDA significantly enhanced the viability of vascular smooth muscle cells (VSMCs) damaged by •OH (P < 0.01), significantly attenuated •OH-derived malondialdehyde production that represents cellular lipid peroxidation (P < 0.05), and significantly increased the glutathione levels in •OH-stressed VSMCs (P < 0.05), indicating the role of 10-HDA in reducing •OH-induced cytotoxicity. Further proteomic analyses of VSMCs identified 195 proteins with decreased expression by •OH challenge that were upregulated by 10-HDA rescue and were primarily involved in protein synthesis (such as translation, protein transport, ribosome, and RNA binding) and energy metabolism (such as fatty acid degradation and glycolysis/gluconeogenesis). Taken together, these findings indicate that 10-HDA can effectively promote cell survival by antagonizing •OH-induced injury in VSMCs. To the best of our knowledge, our results provide the first concrete evidence that 10-HDA-scavenged •OH could be a potential pharmacological application for maintaining vascular health.