Interactions of selected cardiovascular active natural compounds with CXCR4 and CXCR7 receptors: a molecular docking, molecular dynamics, and pharmacokinetic/toxicity prediction study

BACKGROUND

The chemokine CXCL12 and its two receptors (CXCR4 and CXCR7) are involved in inflammation and hematopoietic cell trafficking. This study was designed to investigate molecular docking interactions of four popular cardiovascular-active natural compounds; curcumin, resveratrol, quercetin, and eucalyptol; with these receptors and to predict their drug-like properties. We hypothesize that these compounds can modify CXCL12/CXCR4/CXCR7 pathway offering benefits for coronary artery disease patients.

METHODS

Docking analyses were carried and characterized by Molecular Environment (MOE) software. Protein Data Bank ( http://www.rcsb.org/ ) has been retrieved from protein structure generation and crystal structures of CXCR4 and CXCR7 receptors (PDB code = 3ODU and 6K3F). The active sites of these receptors were evaluated and extracted from full protein and molecular docking protocol was done for compounds against them. The presented parameters included docking scores, ligand binding efficiency, and hydrogen bonding. The pharmacokinetic/toxic properties (ADME/T) were calculated using SwissADME, ProTox-II, and Pred-hERG softwares to predict drug-like properties of the compounds. The thermochemical and molecular orbital analysis, and molecular dynamics simulations were also done.

RESULTS

All compounds showed efficient interactions with the CXCR4 and CXCR7 receptors. The docking scores toward proteins 3ODU of CXCR4 and 6K3F of CXCR7 were - 7.71 and - 7.17 for curcumin, - 5.97 and - 6.03 for quercetin, - 5.68 and - 5.49 for trans-resveratrol, and - 4.88 and - 4.70 for (1 s,4 s)-eucalyptol respectively indicating that all compounds, except quercetin, have more interactions with CXCR4 than with CXCR7. The structurally and functionally important residues in the interactive sites of docked CXCR4-complex and CXCR7-complex were identified. The ADME analysis showed that the compounds have drug-like properties. Only (1 s,4 s)-Eucalyptol has potential weak cardiotoxicity. The results of thermochemical and molecular orbital analysis and molecular dynamics simulation validated outcomes of molecular docking study.

CONCLUSIONS

Curcumin showed the top binding interaction against active sites of CXCR4 and CXCR7 receptors, with the best safety profile, followed by quercetin, resveratrol, and eucalyptol. All compounds demonstrated drug-like properties. Eucalyptol has promising potential because it can be used by inhalation or skin massage. To our knowledge, this is the first attempt to find binding interactions of these natural agents with CXCR4 and CXCR7 receptors and to predict their druggability.

Understanding the molecular basis of cardiomyopathy

Inherited cardiomyopathies are a major cause of mortality and morbidity worldwide and can be caused by mutations in a wide range of proteins located in different cellular compartments. The present review is based on Dr. Ju Chen's 2021 Robert M. Berne Distinguished Lectureship of the American Physiological Society Cardiovascular Section, in which he provided an overview of the current knowledge on the cardiomyopathy-associated proteins that have been studied in his laboratory. The review provides a general summary of the proteins in different compartments of cardiomyocytes associated with cardiomyopathies, with specific focus on the proteins that have been studied in Dr. Chen's laboratory.

Atypical Roles of the Chemokine Receptor ACKR3/CXCR7 in Platelet Pathophysiology

The manifold actions of the pro-inflammatory and regenerative chemokine CXCL12/SDF-1α are executed through the canonical GProteinCoupledReceptor CXCR4, and the non-canonical ACKR3/CXCR7. Platelets express CXCR4, ACKR3/CXCR7, and are a vital source of CXCL12/SDF-1α themselves. In recent years, a regulatory impact of the CXCL12-CXCR4-CXCR7 axis on platelet biogenesis, i.e., megakaryopoiesis, thrombotic and thrombo-inflammatory actions have been revealed through experimental and clinical studies. Platelet surface expression of ACKR3/CXCR7 is significantly enhanced following myocardial infarction (MI) in acute coronary syndrome (ACS) patients, and is also associated with improved functional recovery and prognosis. The therapeutic implications of ACKR3/CXCR7 in myocardial regeneration and improved recovery following an ischemic episode, are well documented. Cardiomyocytes, cardiac-fibroblasts, endothelial lining of the blood vessels perfusing the heart, besides infiltrating platelets and monocytes, all express ACKR3/CXCR7. This review recapitulates ligand induced differential trafficking of platelet CXCR4-ACKR3/CXCR7 affecting their surface availability, and in regulating thrombo-inflammatory platelet functions and survival through CXCR4 or ACKR3/CXCR7. It emphasizes the pro-thrombotic influence of CXCL12/SDF-1α exerted through CXCR4, as opposed to the anti-thrombotic impact of ACKR3/CXCR7. Offering an innovative translational perspective, this review also discusses the advantages and challenges of utilizing ACKR3/CXCR7 as a potential anti-thrombotic strategy in platelet-associated cardiovascular disorders, particularly in coronary artery disease (CAD) patients post-MI.

Low-intensity pulsed ultrasound promotes angiogenesis via the AKT pathway and DNA methylation in human umbilical vein endothelial cells

Angiogenesis involves the activation of endothelial cells (ECs). Low-intensity pulsed ultrasound (LIPUS), which delivers ultrasound waves at a low intensity, can induce the angiogenic potential of ECs. However, the underlying cellular mechanisms remain to be elucidated. In this study, the LIPUS parameters were 1.5 MHz pulsed frequency, 200 us pulse duration, 1.0 kHz repetition rate, and 30 mW/cm² energy intensity. First, we evaluated the effects of LIPUS on the proliferation and angiogenic differentiation of the EC line EA.hy926. The results showed that LIPUS could induce cell proliferation, promote migration, and increase mRNA level inKDR and CD144.Also, the mRNA level and secretion of VEGF were enhanced. We then investigated the role of the AKT signaling pathway in this process. We observed that the expression of p-AKT was upregulated which means that the AKT signaling pathway could be activated by LIPUS, while inhibitor LY294002 of the AKT signaling pathway effectively blocked LIPUS-induced angiogenesis. Finally,we applied confocal Raman microscopy to track biomolecular changes in cells after LIPUS treatment. Spectral analysis showed DNA methylation changes. An Infinium Methylation assay suggested that399 sites were significantly different. After KEGG enrichment analysis, we found seven genes (IRS1, GNG7, COL4A1, FOXO3, COL4A2, CDK4 and EGF) which were closely related to AKT signaling pathway. We verified that AKT signaling pathway inhibition partially blocked LIPUS-induced DNA methylation changes. Ourstudy demonstrated that LIPUS couldpromote the proliferation and angiogenic differentiation of ECs via the AKT signaling pathway. LIPUS could also alter DNA methylation of ECs via the activation of AKT signal.

LncRNA functional annotation with improved false discovery rate achieved by disease associations

The long non‐coding RNAs (lncRNAs) play critical roles in various biological processes and are associated with many diseases. Functional annotation of lncRNAs in diseases attracts great attention in understanding their etiology. However, the traditional co-expression-based analysis usually produces a significant number of false positive function assignments. It is thus crucial to develop a new approach to obtain lower false discovery rate for functional annotation of lncRNAs. Here, a novel strategy termed DAnet which combining disease associations with cis-regulatory network between lncRNAs and neighboring protein-coding genes was developed, and the performance of DAnet was systematically compared with that of the traditional differential expression-based approach. Based on a gold standard analysis of the experimentally validated lncRNAs, the proposed strategy was found to perform better in identifying the experimentally validated lncRNAs compared with the other method. Moreover, the majority of biological pathways (40%∼100%) identified by DAnet were reported to be associated with the studied diseases. In sum, the DAnet is expected to be used to identify the function of specific lncRNAs in a particular disease or multiple diseases.

Trimethylamine N-oxide promotes atherosclerosis via regulating the enriched abundant transcript 1/miR-370-3p/signal transducer and activator of transcription 3/flavin-containing monooxygenase-3 axis

Atherosclerosis (AS) is one of the main causes of cardiovascular diseases (CVDs). Trimethylamine N-oxide (TMAO) exacerbates the development of AS. This study aimed to investigate the roles of TMAO in AS. In this study, mice were fed with high fat food (HF) and/or injected with TMAO. Oil red O staining was applied for histological analysis. ELISA, qRT-PCR, and Western blot were conducted to determine the TMAO, serum, mRNA, and protein levels. CCK-8, colony formation assay, and flow cytometry assays were performed to detect the functions of human aortic endothelial cells (HUVECs). The results showed that TMAO induced thick internal and external walls and intimal plaques in vivo, and HUVEC dysfunction in vitro. TMAO and lncRNA enriched abundant transcript 1 (NEAT1) were increased in AS clinical samples and TMAO-HUVECs. Downregulated NEAT1 inhibited proliferation and promoted the apoptosis of HUVECs. NEAT1 regulated the expression of signal transducer and activator of transcription 3 (STAT3) via sponging miR-370-3p. Overexpression of miR-370-3p facilitated the effects of NEAT1 on the cellular functions of HUVECs, while STAT3 exerted opposing effects. The activation of STAT3 promoted the expression of flavin-containing monooxygenase-3 (FMO3). Taken together, our results show that TMAO-NEAT1/miR-370-3p/STAT3/FMO3 forms a positive feedback loop to exacerbate the development of AS. This novel feedback loop may be a promising therapeutic target for AS.

lncRNA CASC7 regulates pathological progression of ox-LDL-stimulated atherosclerotic cell models via sponging miR-21 and regulating PI3K/Akt and TLR4/NF-κB signaling pathways

Atherosclerosis (AS) is a frequently occurring cause of cardiovascular disease and involves a complicated pathophysiological process. Studies suggest that long non-coding RNAs (lncRNAs) are involved in AS genesis and progression, but mechanisms underlying these connections are unclear. Therefore, this work focused on exploring the role of lncRNA CASC7 in AS. In this study, RNA-seq sequencing results identified 1040 lncRNAs differentially expressed between AS patients and healthy controls. Of these lncRNAs, 458 were up-regulated and 582 were downregulated. CASC7 was found to be down-regulated in serum samples from AS patients and in HUVEC and VSMC exposed to ox-LDL. Overexpression of CASC7 inhibited proliferation and enhanced apoptosis of VSMC, and it markedly reduced IL-1β, IL-6 and TNF-α levels in HUVEC. Increased expression of a CASC7 target, miR-21, abolished the effects of CASC7 on HUVEC and VSMC. Notably, miR-21 targets PI3K in VSMC and TLR4 in HUVEC. The inhibitory effect of CASC7 was decreased by stimulation of PI3K, suggesting that the CASC7/miR-21 axis functions through PI3K/Akt signaling in VSMC. Similarly, the inhibitory effect of CASC7 on the inflammatory response in HUVEC was abolished through activating the TLR4/NF-κB signaling pathway. CASC7 inhibited proliferation and enhanced the apoptosis of VSMC through modulating the miR-21/PI3K-AKT axis, and upregulating CASC7 suppressed the inflammatory response of HUVEC by sponging miR-21 to inhibit the TLR4/NF-κB signal pathway.

Long non‑coding RNA AL355711 promotes smooth muscle cell migration through the ABCG1/MMP3 pathway

Atherosclerosis and related cardiovascular diseases pose severe threats to human health worldwide. There is evidence to suggest that at least 50% of foam cells in atheromas are derived from vascular smooth muscle cells (VSMCs); the first step in this process involves migration to human atherosclerotic lesions. Long non‑coding RNAs (lncRNAs) have been found to play significant roles in diverse biological processes. The present study aimed to investigate the role of lncRNAs in VSMCs. The expression of lncRNAs or mRNAs was detected using reverse transcription‑quantitative polymerase chain reaction. The Gene Expression Omnibus datasets in the NCBI portal were searched using the key words 'Atherosclerosis AND tissue AND Homo sapiens' and the GSE12288 dataset. Gene expression in circulating leukocytes was measured to identify patients with coronary artery disease (CAD) or controls, and used to analyze the correlation coefficient and expression profiles. The protein level of ATP‑binding cassette sub‑family G member 1 (ABCG1) and matrix metalloproteinase (MMP)3 was determined using immunohistochemistry and western blot analysis. The analysis of mouse aortic roots was performed using Masson's and Oil Red O staining. The expression of lncRNA AL355711, ABCG1 and MMP3 was found to be higher in human atherosclerotic plaques or in patients with atherosclerotic CAD. The correlation analysis revealed that ABCG1 may be involved in the regulation between lncRNA AL355711 and MMP3 in atherosclerotic CAD. The knockdown of lncRNA AL355711 inhibited ABCG1 transcription and smooth muscle cell migration. In addition, lncRNA AL355711 was found to regulate MMP3 expression through the ABCG1 pathway. The expression of ABCG1 and MMP3 was found to be high in an animal model of atherosclerosis. The results indicated that lncRNA AL355711 promoted VSMC migration and atherosclerosis partly via the ABCG1/MMP3 pathway. On the whole, the present study demonstrates that the inhibition of lncRNA AL355711 may serve as a novel therapeutic target for atherosclerosis. lncRNA AL355711 in circulating leukocytes may be a novel biomarker for atherosclerotic CAD.

Metformin Improves Stemness of Human Adipose-Derived Stem Cells by Downmodulation of Mechanistic Target of Rapamycin (mTOR) and Extracellular Signal-Regulated Kinase (ERK) Signaling

Adipose tissue plays an important role in regulating metabolic homeostasis by storing excess fat and protecting other organs from lipotoxicity. Aging is associated with central fat redistribution, culminating in a decrease in insulin-sensitive subcutaneous and an increase in insulin-resistant visceral adipose depots. Adipose-derived stem cells (ASCs) play an important role in the regeneration of adipose tissue. Aged ASCs show decreased stemness and regenerative potential due to the accumulation of oxidative stress and mitochondrial dysfunction-related cell damage. Metformin is a well-established anti-diabetic drug that has shown anti-aging effects in different organisms and animal models. In this study, we analyzed the effect of metformin treatment on the stemness of human ASCs in cell culture and whole adipose tissue culture models. Our results demonstrate that metformin improves the stemness of ASCs, reducing their rate of proliferation and adipocyte differentiation. Investigating the possible underlying mechanism, we observed a decrease in the mTOR and ERK activity in metformin-treated ASCs. In addition, we observed an increase in autophagy activity upon metformin treatment. We conclude that metformin treatment improves ASCs stemness by reducing mTOR and ERK signaling and enhancing autophagy. Future in vivo evaluations in animal models and humans will pave the way for the clinical adaptation of this well-established drug for reviving the stemness of aged stem cells.

The Combined Regulation of Long Non-coding RNA and RNA-Binding Proteins in Atherosclerosis

Atherosclerosis is a complex disease closely related to the function of endothelial cells (ECs), monocytes/macrophages, and vascular smooth muscle cells (VSMCs). Despite a good understanding of the pathogenesis of atherosclerosis, the underlying molecular mechanisms are still only poorly understood. Therefore, atherosclerosis continues to be an important clinical issue worthy of further research. Recent evidence has shown that long non-coding RNAs (lncRNAs) and RNA-binding proteins (RBPs) can serve as important regulators of cellular function in atherosclerosis. Besides, several studies have shown that lncRNAs are partly dependent on the specific interaction with RBPs to exert their function. This review summarizes the important contributions of lncRNAs and RBPs in atherosclerosis and provides novel and comprehensible interaction models of lncRNAs and RBPs.

Differential Expression Profiles and Functional Prediction of circRNAs in Necrotizing Enterocolitis

Circular RNAs (circRNAs), a novel type of noncoding RNAs, have been demonstrated to behave as microRNA (miRNA) sponges to exert their effects during pathological processes of diseases. However, the roles of circRNAs have not been explored in necrotizing enterocolitis (NEC). This study sought to identify differentially expressed circRNAs and predict their potential biological functions in NEC. circRNA expression profiles in terminal ileum from newborn rats with NEC and normal controls were explored using next-generation sequencing. In the NEC group, 53 circRNAs were significantly differentially expressed, including 9 upregulated and 44 downregulated. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted, and circRNA-miRNA interaction networks were generated to predict the potential roles of circRNAs in NEC progression. Further investigation revealed that most circRNAs include miRNA binding sites and that some are implicated in NEC development. In conclusion, this study's findings demonstrate that differentially expressed circRNAs are involved in NEC development via their interactions with miRNAs, making them prospective targets for NEC diagnosis and treatment.

LncRNA PVT1 Promotes Hypoxia-Induced Cardiomyocyte Injury by Inhibiting miR-214-3p

OBJECTIVE

To explore the effect and related mechanism of LncRNA PVT1 on hypoxia-induced cardiomyocyte injury.

METHODS

PVT1RNA and miR-214-3p levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell vitality and apoptosis were, respectively, evaluated by Cell Counting Kit-8 (CCK-8) and flow cytometry analysis. Starbase and Dual luciferase reporter (DLR) gene assay was employed to validate the interaction between miR-214-3p and PVT1.

RESULTS

PVT1 was statistically upregulated, and miR-214-3p was statistically downregulated in hypoxia-induced H9c2 cells. The survival rate of H9c2 cells induced by hypoxia decreased statistically, while the apoptosis rate increased statistically (P < 0.05). PVT1 knockdown upregulated the hypoxia-induced H9c2 cell viability and inhibited apoptosis. DLR assay verified the targeting relationship between PVT1 and miR-214-3p. In addition, miR-214-3p inhibitors reversed the viability of H9c2 cells with PVT1 knockout and promoted apoptosis.

CONCLUSION

Silencing PVT1 can enhance the hypoxia-induced H9c2 cell viability and inhibit apoptosis, providing a potential target for the treatment of cardiovascular diseases.

lncRNA RP11-531A24.3 inhibits the migration and proliferation of vascular smooth muscle cells by downregulating ANXA2 expression

A complete understanding of the behavioral influence and phenotypic transition of vascular smooth muscle cells, as well as the effects of the characteristics of these cells on the physiological and pathological processes of atherosclerosis, is crucial if new therapeutic targets for atherosclerosis are to be identified. In the present study, the long non-coding RNA RP11-531A24.3 was identified to be expressed at low levels in plaque tissues through screening a microarray for differentially expressed genes. The functional experimental results suggested that RP11-531A24.3 reduced the viability and inhibited the migration of human aortic vascular smooth muscle cells (HA-VSMCs). RNA antisense purification-mass spectrometry was used to identify the RNA-binding proteins (RBPs) for RP11-531A24.3. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that the pathway with the highest degree of association with RP11-531A24.3 RBPs was related to cell migration. The reduced migration and viability mediated by RP11-531A24.3 overexpression was more significantly suppressed after annexin 2 (ANXA2) depletion in RP11-531A24.3-overexpressing HA-VSMCs. Culture of HA-VSMCs under hypoxic conditions (1% O₂) reduced the expression of RP11-531A24.3, and enhanced the protein expression of ANXA2 and HIF-1α, while knockdown of ANXA2 downregulated the protein expression of HIF-1α. These results suggested that RP11-531A24.3 regulated the proliferation and migration of HA-VSMCs through ANXA2 expression, and hypoxia may be an external factor in the regulation of RP11-531A24.3 and its downstream targets.

Long Non-Coding RNAs in Cardiovascular Diseases: Potential Function as Biomarkers and Therapeutic Targets of Exercise Training

Despite advances in treatments and therapies, cardiovascular diseases (CVDs) remain one of the leading causes of death worldwide. The discovery that most of the human genome, although transcribed, does not encode proteins was crucial for focusing on the potential of long non-coding RNAs (lncRNAs) as essential regulators of cell function at the epigenetic, transcriptional, and post-transcriptional levels. This class of non-coding RNAs is related to the pathophysiology of the cardiovascular system. The different expression profiles of lncRNAs, in different contexts of CVDs, change a great potential in their use as a biomarker and targets of therapeutic intervention. Furthermore, regular physical exercise plays a protective role against CVDs; on the other hand, little is known about its underlying molecular mechanisms. In this review, we look at the accumulated knowledge on lncRNAs and their functions in the cardiovascular system, focusing on the cardiovascular pathology of arterial hypertension, coronary heart disease, acute myocardial infarction, and heart failure. We discuss the potential of these molecules as biomarkers for clinical use, their limitations, and how the manipulation of the expression profile of these transcripts through physical exercise can begin to be suggested as a strategy for the treatment of CVDs.

Long non-coding RNAs in metabolic disorders: pathogenetic relevance and potential biomarkers and therapeutic targets

BACKGROUND

It has been suggested that dysregulation of long non-coding RNAs (lncRNAs) could be associated with the incidence and development of metabolic disorders.

AIM

Accordingly, this narrative review described the molecular mechanisms of lncRNAs in the development of metabolic diseases including insulin resistance, diabetes, obesity, non-alcoholic fatty liver disease (NAFLD), cirrhosis, and coronary artery diseases (CAD). Furthermore, we investigated the up-to-date findings on the association of deregulated lncRNAs in the metabolic disorders, and potential use of lncRNAs as biomarkers and therapeutic targets.

CONCLUSION

LncRNAs/miRNA/regulatory proteins axis plays a crucial role in progression of metabolic disorders and may be used in development of therapeutic and diagnostic approaches.

Circ-USP9X Inhibition Reduces Oxidized Low-density Lipoprotein-induced Endothelial Cell Injury via the microRNA 599/Chloride Intracellular Channel 4 Axis

ABSTRACT

Atherosclerosis (AS) is the common pathological basis of cardiovascular disease. Circular RNA circ-USP9X (hsa_circ_0090231) has been discovered to be upregulated in oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs), but the role of circ-USP9X in ox-LDL-induced endothelial cell injury is indistinct. The purpose of the research was to investigate the role and regulatory mechanism of circ-USP9X in ox-LDL--induced endothelial cell injury. Expression of circ-USP9X was examined by quantitative real-time polymerase chain reaction. Loss-of-function experiments were performed to assess the impacts of circ-USP9X inhibition on viability, cell cycle progression, apoptosis, and tube formation, inflammation, and oxidative stress of ox-LDL-induced HUVEC. The regulatory mechanism of circ-USP9X predicted by bioinformatics analysis and verified by dual-luciferase reporter or RNA immunoprecipitation assays. We observed that circ-USP9X was upregulated in AS patients' serum and ox-LDL-induced HUVEC. Inhibition of circ-USP9X elevated viability, promoted cell cycle progression and angiopoiesis, and decreased apoptosis, inflammation, and oxidative stress of ox-LDL-induced HUVEC. Mechanically, circ-USP9X regulated chloride intracellular channel 4 (CLIC4) messenger RNA expression by sponging microRNA (miR)-599. Furthermore, miR-599 inhibitor overturned circ-USP9X silencing-mediated influence on ox-LDL-induced HUVEC injury. Also, CLIC4 overexpression reversed miR-599 elevation-mediated effect on ox-LDL-induced HUVEC injury. In conclusion, circ-USP9X silencing decreased ox-LDL-induced endothelial cell injury via the miR-599/CLIC4 axis, which offered a novel molecular mechanism to comprehend the pathology of AS.

Expression and Functional Analysis of lncRNAs Involved in Platelet-Derived Growth Factor-BB-Induced Proliferation of Human Aortic Smooth Muscle Cells

Abnormal proliferation of vascular smooth muscle cells (VSMCs) is a common feature of many vascular remodeling diseases. Because long non-coding RNAs (lncRNAs) play a critical role in cardiovascular diseases, we analyzed the key lncRNAs that regulate VSMC proliferation. Microarray analysis identified 2,643 differentially expressed lncRNAs (DELs) and 3,720 differentially expressed coding genes (DEGs) between fetal bovine serum (FBS) starvation-induced quiescent human aortic smooth muscle cells (HASMCs) and platelet-derived growth factor-BB (PDGF-BB)-stimulated proliferative HASMCs. Gene Ontology and pathway analyses of the identified DEGs and DELs demonstrated that many lncRNAs were enriched in pathways related to cell proliferation. One of the upregulated lncRNAs in proliferative HASMC was HIF1A anti-sense RNA 2 (HIF1A-AS2). HIF1A-AS2 suppression decreased HASMC proliferation via the miR-30e-5p/CCND2 mRNA axis. We have thus identified key DELs and DEGs involved in the regulation of PDGF-BB induced HASMC proliferation. Moreover, HIF1A-AS2 promotes HASMC proliferation, suggesting its potential involvement in VSMC proliferative vascular diseases.

Regulation of pyroptosis in cardiovascular pathologies: Role of noncoding RNAs

Cardiovascular disease (CVD) is one of the most important diseases endangering human life. The pathogenesis of CVDs is complex. Pyroptosis, which differs from traditional apoptosis and necrosis, is characterized by cell swelling until membrane rupture, resulting in the release of cell contents and activation of a strong inflammatory response. Recent studies have revealed that inflammation and pyroptosis play important roles in the progression of CVDs. Noncoding RNAs (ncRNAs) are considered promising biomarkers and potential therapeutic targets for the diagnosis and treatment of various diseases, including CVDs. Growing evidence has revealed that ncRNAs can mediate the transcriptional or posttranscriptional regulation of pyroptosis-related genes by participating in the pyroptosis regulatory network. The role and molecular mechanism of pyroptosis-regulating ncRNAs in cardiovascular pathologies are attracting increasing attention. Here, we summarize research progress on pyroptosis and the role of ncRNAs, particularly microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), in the regulation of pyroptosis in CVD pathologies. Identifying these disease-related ncRNAs is important for understanding the pathogenesis of CVDs and providing new targets and ideas for their prevention and treatment.

The Role of the BH4 Cofactor in Nitric Oxide Synthase Activity and Cancer Progression: Two Sides of the Same Coin

Cancer development is associated with abnormal proliferation, genetic instability, cell death resistance, metabolic reprogramming, immunity evasion, and metastasis. These alterations are triggered by genetic and epigenetic alterations in genes that control cell homeostasis. Increased reactive oxygen and nitrogen species (ROS, RNS) induced by different enzymes and reactions with distinct molecules contribute to malignant transformation and tumor progression by modifying DNA, proteins, and lipids, altering their activities. Nitric oxide synthase plays a central role in oncogenic signaling modulation and redox landscape. Overexpression of the three NOS isoforms has been found in innumerous types of cancer contributing to tumor growth and development. Although the main function of NOS is the production of nitric oxide (NO), it can be a source of ROS in some pathological conditions. Decreased tetrahydrobiopterin (BH4) cofactor availability is involved in NOS dysfunction, leading to ROS production and reduced levels of NO. The regulation of NOSs by BH4 in cancer is controversial since BH4 has been reported as a pro-tumoral or an antitumoral molecule. Therefore, in this review, the role of BH4 in the control of NOS activity and its involvement in the capabilities acquired along tumor progression of different cancers was described.

Long non-coding RNA RP11-490M8.1 inhibits lipopolysaccharide-induced pyroptosis of human umbilical vein endothelial cells via the TLR4/NF-κB pathway

BACKGROUND AND AIMS

Pyroptosis is a relatively newly discovered form of programmed cell death that plays an important role in the development of atherosclerosis. Many studies have reported that lncRNAs participated in the regulation of atherosclerosis development. However, the regulatory mechanism of lncRNAs in pyroptosis must be studied further.

METHODS

In a previous study, microarray analysis was used to detect the lncRNA expression profile in three human advanced atherosclerotic plaques and three normal arterial intimae. In the present research, in vitro assays were performed to investigate the role of lncRNA RP11-490M8.1 on pyroptosis. The relative gene mRNA and lncRNA expression levels were tested by quantitative real-time PCR, and protein levels were evaluated by western blot analysis. The RNA hybrid structure was analyzed using the DINAMelt server.

RESULTS

The lncRNA RP11-490M8.1 was significantly downregulated in atherosclerotic plaques and serum. Lipopolysaccharide (LPS) markedly reduced the expression of lncRNA RP11-490M8.1 and induced pyroptosis by increasingthe mRNA and protein levels of NLRP3, caspase-1, ASC, IL-1β, and IL-18 in HUVECs. The promotion effects ofLPS on pyroptosis were markedly suppressed by overexpression of lncRNA RP11-490M8.1. In addition, LPS increased the mRNA and protein levels ofTLR4 and NF-κB, which was also markedly offsetby overexpression of lncRNA RP11-490M8.1.

CONCLUSIONS

These findings indicated that lncRNA RP11-490M8.1 inhibited LPS-induced pyroptosis via the TLR4/NF-κB pathway. Thus, lncRNA RP11-490M8.1 may provide a therapeutic target to ameliorate atherosclerosis.

A Smooth Muscle Cell-Enriched Long Noncoding RNA Regulates Cell Plasticity and Atherosclerosis by Interacting With Serum Response Factor

Objective

Vascular smooth muscle cell (VSMC) plasticity plays a critical role in the development of atherosclerosis. Long noncoding RNAs (lncRNAs) are emerging as important regulators in the vessel wall and impact cellular function through diverse interactors. However, the role of lncRNAs in regulating VSMCs plasticity and atherosclerosis remains unclear.

Approach and Results

We identified a VSMC-enriched lncRNA cardiac mesoderm enhancer-associated noncoding RNA (CARMN) that is dynamically regulated with progression of atherosclerosis. In both mouse and human atherosclerotic plaques, CARMN colocalized with VSMCs and was expressed in the nucleus. Knockdown of CARMN using antisense oligonucleotides in Ldlr−/− mice significantly reduced atherosclerotic lesion formation by 38% and suppressed VSMCs proliferation by 45% without affecting apoptosis. In vitro CARMN gain- and loss-of-function studies verified effects on VSMC proliferation, migration, and differentiation. TGF-β1 (transforming growth factor-beta) induced CARMN expression in a Smad2/3-dependent manner. CARMN regulated VSMC plasticity independent of the miR143/145 cluster, which is located in close proximity to the CARMN locus. Mechanistically, lncRNA pulldown in combination with mass spectrometry analysis showed that the nuclear-localized CARMN interacted with SRF (serum response factor) through a specific 600–1197 nucleotide domain. CARMN enhanced SRF occupancy on the promoter regions of its downstream VSMC targets. Finally, knockdown of SRF abolished the regulatory role of CARMN in VSMC plasticity.

Conclusions

The lncRNA CARMN is a critical regulator of VSMC plasticity and atherosclerosis. These findings highlight the role of a lncRNA in SRF-dependent signaling and provide implications for a range of chronic vascular occlusive disease states.

LncRNAs as Therapeutic Targets and Potential Biomarkers for Lipid-Related Diseases

Lipid metabolism is an essential biological process involved in nutrient adjustment, hormone regulation, and lipid homeostasis. An irregular lifestyle and long-term nutrient overload can cause lipid-related diseases, including atherosclerosis, myocardial infarction (MI), obesity, and fatty liver diseases. Thus, novel tools for efficient diagnosis and treatment of dysfunctional lipid metabolism are urgently required. Furthermore, it is known that lncRNAs based regulation like sponging microRNAs (miRNAs) or serving as a reservoir for microRNAs play an essential role in the progression of lipid-related diseases. Accordingly, a better understanding of the regulatory roles of lncRNAs in lipid-related diseases would provide the basis for identifying potential biomarkers and therapeutic targets for lipid-related diseases. This review highlighted the latest advances on the potential biomarkers of lncRNAs in lipid-related diseases and summarised current knowledge on dysregulated lncRNAs and their potential molecular mechanisms. We have also provided novel insights into the underlying mechanisms of lncRNAs which might serve as potential biomarkers and therapeutic targets for lipid-related diseases. The information presented here may be useful for designing future studies and advancing investigations of lncRNAs as biomarkers for diagnosis, prognosis, and therapy of lipid-related diseases.

Indirect comparison of TIMI, HEART and GRACE for predicting major cardiovascular events in patients admitted to the emergency department with acute chest pain: a systematic review and meta-analysis

BACKGROUND

The study aimed to compare the predictive values of the thrombolysis in myocardial infarction (TIMI); History, Electrocardiography, Age, Risk factors and Troponin (HEART) and Global Registry in Acute Coronary Events (GRACE) scoring systems for major adverse cardiovascular events (MACEs) in acute chest pain (ACP) patients admitted to the emergency department (ED).

METHODS

We systematically searched PubMed, Embase and the Cochrane Library from their inception to June 2020; we compared the following parameters: sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), diagnostic OR (DOR) and area under the receiver operating characteristic curves (AUC).

RESULTS

The pooled sensitivity and specificity for TIMI, HEART and GRACE were 0.95 and 0.36, 0.96 and 0.50, and 0.78 and 0.56, respectively. The pooled PLR and NLR for TIMI, HEART and GRACE were 1.49 and 0.13, 1.94 and 0.08, and 1.77 and 0.40, respectively. The pooled DOR for TIMI, HEART and GRACE was 9.18, 17.92 and 4.00, respectively. The AUC for TIMI, HEART and GRACE was 0.80, 0.80 and 0.70, respectively. Finally, the results of indirect comparison suggested the superiority of values of TIMI and HEART to those of GRACE for predicting MACEs, while there were no significant differences between TIMI and HEART for predicting MACEs.

CONCLUSIONS

TIMI and HEART were superior to GRACE for predicting MACE risk in ACP patients admitted to the ED.

LINC01123 promotes cell proliferation and migration via regulating miR-1277-5p/KLF5 axis in ox-LDL-induced vascular smooth muscle cells

The pathophysiological mechanism of carotid atherosclerosis (CAS) involves endothelial cell dysfunction, vascular smooth muscle cells (VSMCs), and macrophage activation, which ultimately leads to fibrosis of the vessel wall. lncRNA works weightily in the formation of CAS, but the function and mechanism of lncRNA LINC01123 in stable plaque formation are still equivocal. We collected blood samples from 35 CAS patients as well as 33 healthy volunteers. VSMCs treated with oxidized low-density lipoprotein (ox-LDL) were utilized as the CAS cell models. We applied qRT-PCR for detecting LINC01123, miR-1277-5p and KLF5 mRNA expression, CCK-8 method and BrdU test for determining cell proliferation, Transwell test for measuring cell migration, as well as Western blot for assaying KLF5 protein expression. Dual-luciferase reporter experiment was adopted for assessing the interaction between LINC01123 and miR-1277-5p, as well as KLF5 and miR-1277-5p. LINC01123 and KLF5 expression were dramatically up-regulated, while miR-1277-5p expression was down-regulated in CAS patients and ox-LDL-induced CAS cell models. Overexpressed LINC01123 notedly promoted VSMCs migration and proliferation. LINC01123 knockdown repressed cell proliferation and migration. Also, LINC01123 targeted miR-1277-5p and down-regulated its expression, while miR-1277-5p could negatively regulate KLF5 expression. LINC01123 is highly expressed in CAS patients, and promotes cell proliferation and migration via regulating miR-1277-5p/KLF5 axis in ox-LDL-induced VSMCs. It might be involved in the fibrous plaque formation.

Effects of shear stress on differentiation of stem cells into endothelial cells

Stem cell transplantation is an appealing potential therapy for vascular diseases and an indispensable key step in vascular tissue engineering. Substantial effort has been made to differentiate stem cells toward vascular cell phenotypes, including endothelial cells (ECs) and smooth muscle cells. The microenvironment of vascular cells not only contains biochemical factors that influence differentiation but also exerts hemodynamic forces, such as shear stress and cyclic strain. More recently, studies have shown that shear stress can influence the differentiation of stem cells toward ECs. A deep understanding of the responses and underlying mechanisms involved in this process is essential for clinical translation. This review highlights current data supporting the role of shear stress in stem cell differentiation into ECs. Potential mechanisms and signaling cascades for transducing shear stress into a biological signal are proposed. Further study of stem cell responses to shear stress will be necessary to apply stem cells for pharmacological applications and cardiovascular implants in the realm of regenerative medicine.

Nascent RNA antagonizes the interaction of a set of regulatory proteins with chromatin

A number of regulatory factors are recruited to chromatin by specialized RNAs. Whether RNA has a more general role in regulating the interaction of proteins with chromatin has not been determined. We used proteomics methods to measure the global impact of nascent RNA on chromatin in embryonic stem cells. Surprisingly, we found that nascent RNA primarily antagonized the interaction of chromatin modifiers and transcriptional regulators with chromatin. Transcriptional inhibition and RNA degradation induced recruitment of a set of transcriptional regulators, chromatin modifiers, nucleosome remodelers, and regulators of higher-order structure. RNA directly bound to factors, including BAF, NuRD, EHMT1, and INO80 and inhibited their interaction with nucleosomes. The transcriptional elongation factor P-TEFb directly bound pre-mRNA, and its recruitment to chromatin upon Pol II inhibition was regulated by the 7SK ribonucleoprotein complex. We postulate that by antagonizing the interaction of regulatory proteins with chromatin, nascent RNA links transcriptional output with chromatin composition.

LncRNA NORAD Promotes Vascular Endothelial Cell Injury and Atherosclerosis Through Suppressing VEGF Gene Transcription via Enhancing H3K9 Deacetylation by Recruiting HDAC6

Coronary artery disease (CAD) is a major atherosclerotic cardiovascular disease and the leading cause of mortality globally. Long non-coding RNAs (lncRNAs) play crucial roles in CAD development. To date, the effect of lncRNA non-coding RNA activated by DNA damage (NORAD) on atherosclerosis in CAD remains unclear. The primary aim of this study was to investigate the effect of lncRNA NORAD on vascular endothelial cell injury and atherosclerosis. Here, ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE^–/– mice were utilized as in vitro and in vivo models. The present study found that lncRNA NORAD expression was increased in ox-LDL-treated HUVECs and thoracic aorta of atherosclerotic mice, and knockdown of lncRNA NORAD alleviated vascular endothelial cell injury and atherosclerosis development in vitro and in vivo. Knockdown of lncRNA NORAD aggravated ox-LDL-reduced or atherosclerosis-decreased vascular endothelial growth factor (VEGF) expression in HUVECs and thoracic aorta of mice to ameliorate vascular endothelial cell injury and atherosclerosis development. Moreover, nucleus lncRNA NORAD suppressed VEGF gene transcription through enhancing H3K9 deacetylation via recruiting HDAC6 to the VEGF gene promoter in ox-LDL-treated HUVECs. In addition, VEGF reduced FUS (FUS RNA binding protein) expression by a negative feedback regulation in HUVECs. In summary, lncRNA NORAD enhanced vascular endothelial cell injury and atherosclerosis through suppressing VEGF gene transcription via enhancing H3K9 deacetylation by recruiting HDAC6. The findings could facilitate discovering novel diagnostic markers and therapeutic targets for CAD.

Emerging Role of Long Non-Coding RNAs in Diabetic Vascular Complications

Chronic metabolic disorders such as obesity and diabetes are associated with accelerated rates of macrovascular and microvascular complications, which are leading causes of morbidity and mortality worldwide. Further understanding of the underlying molecular mechanisms can aid in the development of novel drug targets and therapies to manage these disorders more effectively. Long non-coding RNAs (lncRNAs) that do not have protein-coding potential are expressed in a tissue- and species-specific manner and regulate diverse biological processes. LncRNAs regulate gene expression in cis or in trans through various mechanisms, including interaction with chromatin-modifying proteins and other regulatory proteins and via posttranscriptional mechanisms, including acting as microRNA sponges or as host genes of microRNAs. Emerging evidence suggests that major pathological factors associated with diabetes such as high glucose, free fatty acids, proinflammatory cytokines, and growth factors can dysregulate lncRNAs in inflammatory, cardiac, vascular, and renal cells leading to altered expression of key inflammatory genes and fibrotic genes associated with diabetic vascular complications. Here we review recent reports on lncRNA characterization, functions, and mechanisms of action in diabetic vascular complications and translational approaches to target them. These advances can provide new insights into the lncRNA-dependent actions and mechanisms underlying diabetic vascular complications and uncover novel lncRNA-based biomarkers and therapies to reduce disease burden and mortality.

Epigenetic Regulation of Autophagy in Cardiovascular Pathobiology

Cardiovascular diseases (CVDs) are the number one cause of debilitation and mortality worldwide, with a need for cost-effective therapeutics. Autophagy is a highly conserved catabolic recycling pathway triggered by various intra- or extracellular stimuli to play an essential role in development and pathologies, including CVDs. Accordingly, there is great interest in identifying mechanisms that govern autophagic regulation. Autophagic regulation is very complex and multifactorial that includes epigenetic pathways, such as histone modifications to regulate autophagy-related gene expression, decapping-associated mRNA degradation, microRNAs, and long non-coding RNAs; pathways are also known to play roles in CVDs. Molecular understanding of epigenetic-based pathways involved in autophagy and CVDs not only will enhance the understanding of CVDs, but may also provide novel therapeutic targets and biomarkers for CVDs.

Linc-KIAA1737-2 promoted LPS-induced HK-2 cell apoptosis by regulating miR-27a-3p/TLR4/NF-κB axis

Inflammation and renal cell apoptosis participate in sepsis-induced acute kidney injury. Previous research found the upregulation of long non-coding RNA Linc-KIAA1737–2 in hypoxia- or inflammation-challenged human proximal tubular epithelial cells, but its role in sepsis-induced acute kidney injury is underexplored. In this research, we found that Linc-KIAA1737–2 could be upregulated in HK-2 human proximal tubular epithelial cells by LPS treatment, and knock-down of this lncRNA significantly attenuated LPS-induced apoptosis in HK-2 cells, while its overexpression showed opposite effect. MiR-27a-3p was confirmed to interact with Linc-KIAA1737–2 in HK-2 cells by RNA pull-down and dual-luciferase assay. MiR-27a-3p mimic transfection significantly attenuated LPS-induced HK-2 cell apoptosis by downregulating the protein levels of TLR4 and NF-κB, which was overturned by overexpression of Linc-KIAA1737–2. Our results suggested that Linc-KIAA1737–2 could promote LPS-induced apoptosis in HK-2 cells, and presumably sepsis-induced acute kidney injury, by regulating the miR-27a-3p/TLR4/NF-κB axis.

Smooth Muscle Specific Ablation of CXCL12 in Mice Downregulates CXCR7 Associated with Defective Coronary Arteries and Cardiac Hypertrophy

The chemokine CXCL12 plays a fundamental role in cardiovascular development, cell trafficking, and myocardial repair. Human genome-wide association studies even have identified novel loci downstream of the CXCL12 gene locus associated with coronary artery disease and myocardial infarction. Nevertheless, cell and tissue specific effects of CXCL12 are barely understood. Since we detected high expression of CXCL12 in smooth muscle (SM) cells, we generated a SM22-alpha-Cre driven mouse model to ablate CXCL12 (SM-CXCL12^−/−). SM-CXCL12^−/− mice revealed high embryonic lethality (50%) with developmental defects, including aberrant topology of coronary arteries. Postnatally, SM-CXCL12^−/− mice developed severe cardiac hypertrophy associated with fibrosis, apoptotic cell death, impaired heart function, and severe coronary vascular defects characterized by thinned and dilated arteries. Transcriptome analyses showed specific upregulation of pathways associated with hypertrophic cardiomyopathy, collagen protein network, heart-related proteoglycans, and downregulation of the M2 macrophage modulators. CXCL12 mutants showed endothelial downregulation of the CXCL12 co-receptor CXCR7. Treatment of SM-CXCL12^−/− mice with the CXCR7 agonist TC14012 attenuated cardiac hypertrophy associated with increased pERK signaling. Our data suggest a critical role of smooth muscle-specific CXCL12 in arterial development, vessel maturation, and cardiac hypertrophy. Pharmacological stimulation of CXCR7 might be a promising target to attenuate adverse hypertrophic remodeling.

Factors Affecting the Re-Endothelialization of Endothelial Progenitor Cell

The vascular endothelium, which plays an essential role in maintaining the normal shape and function of blood vessels, is a natural barrier between the circulating blood and the vascular wall tissue. The endothelial damage can cause vascular lesions, such as atherosclerosis and restenosis. After the vascular intima injury, the body starts the endothelial repair (re-endothelialization) to inhibit the neointimal hyperplasia. Endothelial progenitor cell is the precursor of endothelial cells and plays an important role in the vascular re-endothelialization. However, re-endothelialization is inevitably affected in vivo and in vitro by factors, which can be divided into two types, namely, promotion and inhibition, and act on different links of the vascular re-endothelialization. This article reviews these factors and related mechanisms.

Therapies Targeted at Non-Coding RNAs in Prevention and Limitation of Myocardial Infarction and Subsequent Cardiac Remodeling-Current Experience and Perspectives

Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented.

Role of R-spondin 2 in arterial lymphangiogenesis and atherosclerosis

AIMS

Impaired lymphatic drainage of the arterial wall results in intimal lipid accumulation and atherosclerosis. However, the mechanisms regulating lymphangiogenesis in atherosclerotic arteries are not well understood. Our studies identified elevated levels of matrix protein R-spondin 2 (RSPO2) in atherosclerotic arteries. In this study, we investigated the role of RSPO2 in lymphangiogenesis, arterial cholesterol efflux into lesion-draining lymph nodes (LNs) and development of atherosclerosis.

METHODS AND RESULTS

The effect of RSPO2 on lymphangiogenesis was investigated using human lymphatic endothelial cells (LEC) in vitro and implanted Matrigel plugs in vivo. Cellular and molecular approaches, pharmacological agents, and siRNA silencing of RSPO2 receptor LGR4 were used to investigate RSPO2-mediated signalling in LEC. In vivo low-density lipoprotein (LDL) tracking and perivascular blockade of RSPO2-LGR4 signalling using LGR4-extracellular domain (ECD) pluronic gel in hypercholesterolemic mice were utilized to investigate the role of RSPO2 in arterial reverse cholesterol transport and atherosclerosis. Immunoblotting and imaging experiments demonstrated increased RSPO2 expression in human and mouse atherosclerotic arteries compared to non-atherosclerotic controls. RSPO2 treatment inhibited lymphangiogenesis both in vitro and in vivo. LGR4 silencing and inhibition of RSPO2-LGR4 signalling abrogated RSPO2-induced inhibition of lymphangiogenesis. Mechanistically, we found that RSPO2 suppresses PI3K-AKT-endothelial nitric oxide synthase (eNOS) signalling via LGR4 and inhibits activation of the canonical Wnt-β-catenin pathway. ApoE-/- mice treated with LGR4-ECD developed significantly less atherosclerosis compared with control treatment. Finally, increased arterial lymphatic vessel density and improved lymphatic drainage of fluorescently labelled LDL to deep cervical LNs were observed in LGR4-ECD-treated mice.

CONCLUSION

These findings demonstrate that RSPO2 inhibits lymphangiogenesis via LGR4 and downstream impairment of AKT-eNOS-nitric oxide signalling. These results may also inform new therapeutic strategies to promote lymphangiogenesis and improve cholesterol efflux from atherosclerotic arteries.

Integrated bioinformatics analysis reveals novel key biomarkers and potential candidate small molecule drugs in gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is the metabolic disorder that appears during pregnancy. The current investigation aimed to identify central differentially expressed genes (DEGs) in GDM. The transcription profiling by array data (E-MTAB-6418) was obtained from the ArrayExpress database. The DEGs between GDM samples and non-GDM samples were analyzed. Functional enrichment analysis were performed using ToppGene. Then we constructed the protein–protein interaction (PPI) network of DEGs by the Search Tool for the Retrieval of Interacting Genes database (STRING) and module analysis was performed. Subsequently, we constructed the miRNA–hub gene network and TF–hub gene regulatory network. The validation of hub genes was performed through receiver operating characteristic curve (ROC). Finally, the candidate small molecules as potential drugs to treat GDM were predicted by using molecular docking. Through transcription profiling by array data, a total of 869 DEGs were detected including 439 up-regulated and 430 down-regulated genes. Functional enrichment analysis showed these DEGs were mainly enriched in reproduction, cell adhesion, cell surface interactions at the vascular wall and extracellular matrix organization. Ten genes, HSP90AA1, EGFR, RPS13, RBX1, PAK1, FYN, ABL1, SMAD3, STAT3 and PRKCA were associated with GDM, according to ROC analysis. Finally, the most significant small molecules were predicted based on molecular docking. This investigation identified hub genes, signal pathways and therapeutic agents, which might help us, enhance our understanding of the mechanisms of GDM and find some novel therapeutic agents for GDM.

Molecular and Biological Mechanisms Underlying Gender Differences in COVID-19 Severity and Mortality

Globally, over two million people have perished due to the recent pandemic caused by SARS-CoV-2. The available epidemiological global data for SARS-CoV-2 portrays a higher rate of severity and mortality in males. Analyzing gender differences in the host mechanisms involved in SARS-CoV-2 infection and progression may offer insight into the more detrimental disease prognosis and clinical outcome in males. Therefore, we outline sexual dimorphisms which exist in particular host factors and elaborate on how they may contribute to the pronounced severity in male COVID-19 patients. This includes disparities detected in comorbidities, the ACE2 receptor, renin-angiotensin system (RAS), signaling molecules involved in SARS-CoV-2 replication, proteases which prime viral S protein, the immune response, and behavioral considerations. Moreover, we discuss sexual disparities associated with other viruses and a possible gender-dependent response to SARS-CoV-2 vaccines. By specifically highlighting these immune-endocrine processes as well as behavioral factors that differentially exist between the genders, we aim to offer a better understanding in the variations of SARS-CoV-2 pathogenicity.

Regulation of Long Non-Coding RNAs by Statins in Atherosclerosis

Despite increased public health awareness, atherosclerosis remains a leading cause of mortality worldwide. Significant variations in response to statin treatment have been noted among different populations suggesting that the efficacy of statins may be altered by both genetic and environmental factors. The existing literature suggests that certain long noncoding RNAs (lncRNAs) might be up- or downregulated among patients with atherosclerosis. LncRNA may act on multiple levels (cholesterol homeostasis, vascular inflammation, and plaque destabilization) and exert atheroprotective or atherogenic effects. To date, only a few studies have investigated the interplay between statins and lncRNAs known to be implicated in atherosclerosis. The current review characterizes the role of lncRNAs in atherosclerosis and summarizes the available evidence related to the effect of statins in regulating lncRNAs.

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

The abnormal proliferation of vascular smooth muscle cells (VSMCs) is crucial in the atherosclerosis. Although long noncoding RNAs (lncRNAs) are implicated in a variety of diseases, their roles in activation of VSMCs proliferation and vascular disorder diseases are not well understood. In addition, heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2/B1) was reported to participate in lncRNAs-mediated function. Herein, we propose to investigate the role of lncRNA AC105942.1 and hnRNPA2/B1 in pathological VSMCs proliferation and the possible mechanisms in vitro. We have identified that lncRNA AC105942.1 was downregulated and hnRNPA2/B1 was upregulated in atherosclerotic plaques compared with normal artery tissues. Enhanced lncRNA AC105942.1 could noticeably inhibit Ang II-induced VSMCs proliferation. Further investigation suggested that lncRNA AC105942.1 could downregulate the expression of hnRNPA2/B1 and then regulate the level of CDK4 and p27. Taken together, our study indicated that lncRNA AC105942.1 downregulated hnRNPA2B1 to protect against the atherosclerosis by suppressing VSMCs proliferation. LncRNA AC105942.1 and hnRNPA2/B1 could represent potential therapeutic and diagnostic targets to atherosclerosis-related diseases.

Impaired activity of circulating EPCs and endothelial function are associated with increased Syntax score in patients with coronary artery disease

It has previously been shown that the number of endothelial progenitor cells (EPCs) is negatively correlated with Syntax score in patients with coronary artery disease (CAD). However, the association between alterations in EPC function and Syntax score is still unknown. The present study evaluated the association between the activity of EPCs as well as endothelial function and Syntax score in patients with CAD and investigated the underlying mechanisms. A total of 60 patients with CAD were enrolled in 3 groups according to Syntax score, and 20 healthy subjects were recruited as the control group. The number and migratory, proliferative and adhesive activities of circulating EPCs were studied. The endothelial function was measured by flow-mediated dilatation (FMD) and the levels of nitric oxide (NO) in plasma or secreted by EPCs were detected. The number and activity of circulating EPCs were lower in patients with a high Syntax score, which was similar to the alteration in FMD. The level of NO in plasma or secreted by EPCs also decreased as Syntax score increased. There was a negative association between FMD or circulating EPCs and Syntax score. A similar association was observed between the levels of NO in plasma or secreted by EPCs and Syntax score. Patients with CAD who had a higher Syntax score exhibited lower EPC numbers or activity and weaker endothelial function, which may be associated with attenuated NO production. These findings provide novel surrogate parameters for evaluation of the severity and complexity of CAD.

Promoter polymorphisms in the lncRNA-MIAT gene associated with acute myocardial infarction in Chinese Han population: a case-control study

BACKGROUND

Coronary atherosclerotic disease (CAD) is one of the greatest causes of death and disability around the world, and has emerged as a major public health problem. Acute myocardial infarction (AMI) is the most serious type of CAD. Myocardial infarction (MI) association transcript (MIAT) has demonstrated that it plays an important role in AMI.

PURPOSE

To investigate the association between MIAT promoter polymorphisms and AMI in Chinese Han population.

METHODS

A total of 212 AMI patients and 218 healthy controls were recruited. The long non-coding RNA (lncRNA)-MIAT promoter polymorphisms (single nucleotide polymorphisms (SNPs)) were obtained using polymerase chain reaction (PCR) and sequencing techniques. Chi-square test was used to analyze the allele and genotype frequencies of each SNP in two groups. Logistic regression analysis was used to analyze the association of each SNP with AMI. Linkage disequilibrium (LD) and haplotype analysis were performed using SHEsis software. A JASPAR database search predicts transcription factors transition of linked polymorphism in MIAT promoter.

RESULTS

Ten SNPs were found, including rs56371714, rs55892869, rs151057042, rs2157598, rs150465374, rs5761664, rs8142890, rs5752375, rs9608515 and rs1055293700, whereas rs1055293700 was found only in the control group. Single and logistic regression analysis showed that there was a significant correlation between rs5752375 and rs9608515 polymorphisms and AMI, while other sites had no relationship with AMI. These MI association polymorphisms may change the binding sites with transcription factor.

CONCLUSIONS

The polymorphisms of lncRNA-MIAT promoter rs5752375 and rs9608515 were significantly associated with AMI in Chinese Han population. This result would be of clinical importance for the early diagnosis of AMI.

The cardiac translational landscape reveals that micropeptides are new players involved in cardiomyocyte hypertrophy

Hypertrophic growth of cardiomyocytes is one of the major compensatory responses in the heart after physiological or pathological stimulation. Protein synthesis enhancement, which is mediated by the translation of messenger RNAs, is one of the main features of cardiomyocyte hypertrophy. Although the transcriptome shift caused by cardiac hypertrophy induced by different stimuli has been extensively investigated, translatome dynamics in this cellular process has been less studied. Here, we generated a nucleotide-resolution translatome as well as transcriptome data from isolated primary cardiomyocytes undergoing hypertrophy. More than 10,000 open reading frames (ORFs) were detected from the deep sequencing of ribosome-protected fragments (Ribo-seq), which orchestrated the shift of the translatome in hypertrophied cardiomyocytes. Our data suggest that rather than increase the translational rate of ribosomes, the increased efficiency of protein synthesis in cardiomyocyte hypertrophy was attributable to an increased quantity of ribosomes. In addition, more than 100 uncharacterized short ORFs (sORFs) were detected in long noncoding RNA genes from Ribo-seq with potential of micropeptide coding. In a random test of 15 candidates, the coding potential of 11 sORFs was experimentally supported. Three micropeptides were identified to regulate cardiomyocyte hypertrophy by modulating the activities of oxidative phosphorylation, the calcium signaling pathway, and the mitogen-activated protein kinase (MAPK) pathway. Our study provides a genome-wide overview of the translational controls behind cardiomyocyte hypertrophy and demonstrates an unrecognized role of micropeptides in cardiomyocyte biology.

Endothelium-dependent remote signaling in ischemia and reperfusion: Alterations in the cardiometabolic continuum

Intact endothelial function plays a fundamental role for the maintenance of cardiovascular (CV) health. The endothelium is also involved in remote signaling pathway-mediated protection against ischemia/reperfusion (I/R) injury. However, the transfer of these protective signals into clinical practice has been hampered by the complex metabolic alterations frequently observed in the cardiometabolic continuum, which affect redox balance and inflammatory pathways. Despite recent advances in determining the distinct roles of hyperglycemia, insulin resistance (InR), hyperinsulinemia, and ultimately diabetes mellitus (DM), which define the cardiometabolic continuum, our understanding of how these conditions modulate endothelial signaling remains challenging. It is widely accepted that endothelial cells (ECs) undergo functional changes within the cardiometabolic continuum. Beyond vascular tone and platelet-endothelium interaction, endothelial dysfunction may have profound negative effects on outcome during I/R. In this review, we summarize the current knowledge of the influence of hyperglycemia, InR, hyperinsulinemia, and DM on endothelial function and redox balance, their influence on remote protective signaling pathways, and their impact on potential therapeutic strategies to optimize protective heterocellular signaling.

The Long Noncoding RNA RP11-728F11.4 Promotes Atherosclerosis

OBJECTIVE

Noncoding RNAs are emerging as important players in gene regulation and cardiovascular diseases. Their roles in the pathogenesis of atherosclerosis are not fully understood. The purpose of this study was to determine the role played by a previously uncharacterized long noncoding RNA, RP11-728F11.4, in the development of atherosclerosis and the mechanisms by which it acts. Approach and Results: Expression microarray analysis revealed that atherosclerotic plaques had increased expression of RP11-728F11.4 as well as the cognate gene FXYD6 (FXYD domain containing ion transport regulator 6), which encodes a modulator of Na+/K+-ATPase. In vitro experiments showed that RP11-728F11.4 interacted with the RNA-binding protein EWSR1 (Ewings sarcoma RNA binding protein-1) and upregulated FXYD6 expression. Lentivirus-induced overexpression of RP11-728F11.4 in cultured monocytes-derived macrophages resulted in higher Na+/K+-ATPase activity, intracellular cholesterol accumulation, and increased proinflammatory cytokine production. The effects of RP11-728F11.4 were enhanced by siRNA-mediated knockdown of EWSR1 and reduced by downregulation of FXYD domain containing ion transport regulator 6. In vivo experiments in apoE knockout mice fed a Western diet demonstrated that RP11-728F11.4 increased proinflammatory cytokine production and augmented atherosclerotic lesions.

CONCLUSIONS

RP11-728F11.4 promotes atherosclerosis, with an influence on cholesterol homeostasis and proinflammatory molecule production, thus representing a potential therapeutic target. Graphic Abstract: A graphic abstract is available for this article.

The Emerging Role of Long Non-coding RNAs and Circular RNAs in Coronary Artery Disease

Coronary artery disease (CAD) is a common disorder caused by atherosclerotic processes in the coronary arteries. This condition results from abnormal interactions between numerous cell types in the artery walls. The main participating factors in this process are accumulation of lipid deposits, endothelial cell dysfunction, macrophage induction, and changes in smooth muscle cells. Several lines of evidence underscore participation of long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) in the pathogenesis of CAD. Several lncRNAs such as H19, ANRIL, MIAT, lnc-DC, IFNG-AS1, and LEF1-AS1 have been shown to be up-regulated in the biological materials obtained from CAD patients. On the other hand, Gas5, Chast, HULC, DICER1-AS1, and MEG3 have been down-regulated in CAD patients. Meanwhile, a number of circRNAs have been demonstrated to influence function of endothelial cells or vascular smooth muscle cells, thus contributing to the pathogenesis of CAD. In the current review, we summarize the function of lncRNAs and circRNAs in the development and progression of CAD.

Exosomes in atherosclerosis: performers, bystanders, biomarkers, and therapeutic targets

Exosomes are nanosized lipid vesicles originating from the endosomal system that carry many macromolecules from their parental cells and play important roles in intercellular communication. The functions and underlying mechanisms of exosomes in atherosclerosis have recently been intensively studied. In this review, we briefly introduce exosome biology and then focus on advances in the roles of exosomes in atherosclerosis, specifically exosomal changes associated with atherosclerosis, their cellular origins and potential functional cargos, and their detailed impacts on recipient cells. We also discuss the potential of exosomes as biomarkers and drug carriers for managing atherosclerosis.

Importance of β2AR elevation for re-endothelialization capacity mediated by late endothelial progenitor cells in hypertensive patients

Dysfunction of late endothelial progenitor cells (EPCs) has been suggested to be associated with hypertension. β2-Adrenergic receptor (β2AR) is a novel and key target for EPC homing. Here, we proposed that attenuated β2AR signaling contributes to EPCs dysfunction, whereas enhanced β2AR signaling restores EPCs' functions in hypertension. EPCs derived from hypertensive patients exhibited reduced cell number, impaired in vitro migratory and adhesion abilities, and impaired re-endothelialization after transplantation in nude mice with carotid artery injury. β2AR expression of EPCs from hypertensive patients was markedly downregulated, whereas the phosphorylation of the p38 mitogen-activated protein kinase (p38-MAPK) was elevated. The cleaved caspase-3 levels were elevated in EPCs. The overexpression of β2AR in EPCs from hypertensive patients inhibited p38-MAPK signaling, whereas it enhanced in vitro EPC proliferation, migration, and adhesion and in vivo re-endothelialization. The β2AR-mediated effects were attenuated by treating the EPCs with a neutralizing monoclonal antibody against β2AR, which could be partially antagonized by the p38-MAPK inhibitor SB203580. Moreover, shear stress stimulation, a classic nonpharmacological intervention, increased the phosphorylation levels of β2AR and enhanced the in vitro and in vivo functions of EPCs from hypertensive patients. Collectively, the current investigation demonstrated that impaired β2AR/p38-MAPK/caspase-3 signaling at least partially reduced the re-endothelialization capacity of EPCs from hypertensive patients. Restoration of β2AR expression and shear stress treatment could improve their endothelial repair capacity by regulating the p38-MAPK/caspase-3 signaling pathway. The clinical significance of β2AR in endothelium repair still requires further investigation.NEW & NOTEWORTHY Impaired β2-adrenergic receptor (β2AR) expression with an elevation of p38-MAPK/caspase-3 signaling at least partially contributes to the decline of re-endothelialization capacity of late endothelial progenitor cells (EPCs) from hypertensive patients. β2AR gene transfer and shear stress treatment improve the late EPC-mediated enhancement of the re-endothelialization capacity in hypertensive patients through activating β2AR/p38-MAPK/caspase-3 signaling. The present study is the first to reveal the potential molecular mechanism of the impaired endothelium-reparative capacity of late EPCs in hypertension after vascular injury and strongly suggests that β2AR is a novel and crucial therapeutic target for increasing EPC-mediated re-endothelialization capacity in hypertension.

Long non-coding RNAs: the tentacles of chromatin remodeler complexes

Chromatin remodeler complexes regulate gene transcription, DNA replication and DNA repair by changing both nucleosome position and post-translational modifications. The chromatin remodeler complexes are categorized into four families: the SWI/SNF, INO80/SWR1, ISWI and CHD family. In this review, we describe the subunits of these chromatin remodeler complexes, in particular, the recently identified members of the ISWI family and novelties of the CHD family. Long non-coding (lnc) RNAs regulate gene expression through different epigenetic mechanisms, including interaction with chromatin remodelers. For example, interaction of lncBRM with BRM inhibits the SWI/SNF complex associated with a differentiated phenotype and favors assembly of a stem cell-related SWI/SNF complex. Today, over 50 lncRNAs have been shown to affect chromatin remodeler complexes and we here discuss the mechanisms involved.

LncRNA CHRF aggravates myocardial ischemia/reperfusion injury by enhancing autophagy via modulation of the miR-182-5p/ATG7 pathway

Myocardial ischemia/reperfusion (I/R) injury is a very frequent cardiovascular disease and one of the leading causes of death. Abundant evidence has shown that long noncoding RNAs (lncRNAs) are crucial players in myocardial I/R injury. LncRNA cardiac hypertrophy-related factor (CHRF) has been revealed as an important modulator in cardiac disease. However, the function of CHRF in myocardial I/R injury is unclear. In our current work, we found that the expression of CHRF was upregulated in myocardial I/R injury models. Suppression of CHRF relieved myocardial I/R injury in vivo. In addition, in vitro silencing of CHRF enhanced cell viability and attenuated lactate dehydrogenase activity (LDH) as well as apoptosis in H9C2 cells treated with hypoxia/reoxygenation injury. Autophagy has been studied to play an important role in myocardial I/R injury. Thus, experiments related to autophagy were done, and the results showed that CHRF knockdown decreased autophagy. For the exploration of the regulatory mechanism, we found that CHRF sequestered and negatively regulated miR-182-5p to release its inhibition on ATG7. Findings from rescue assays revealed that ATG7 overexpression could suppress the effects of CHRF silence on cell viability, LDH level, apoptosis, and autophagy. To sum up, our results suggested that CHRF exacerbated myocardial I/R injury by enhancing autophagy via modulation of the miR-182-5p/ATG7 pathway. Therefore, this competing endogenous RNA axis may be a potential therapeutic biomarker for myocardial I/R injury.

The transcriptome-wide association search for genes and genetic variants which associate with BMI and gestational weight gain in women with type 1 diabetes

BACKGROUND

Clinical data suggest that BMI and gestational weight gain (GWG) are strongly interconnected phenotypes; however, the genetic basis of the latter is rather unclear. Here we aim to find genes and genetic variants which influence BMI and/or GWG.

METHODS

We have genotyped 316 type 1 diabetics using Illumina Infinium Omni Express Exome-8 v1.4 arrays. The GIANT, ARIC and T2D-GENES summary statistics were used for TWAS (performed with PrediXcan) in adipose tissue. Next, the analysis of association of imputed expression with BMI in the general and diabetic cohorts (Analysis 1 and 2) or GWG (Analysis 3 and 4) was performed, followed by variant association analysis (1 Mb around identified loci) with the mentioned phenotypes.

RESULTS

In Analysis 1 we have found 175 BMI associated genes and 19 variants (p < 10-4) which influenced GWG, with the strongest association for rs11465293 in CCL24 (p = 3.18E-06). Analysis 2, with diabetes included in the model, led to discovery of 1812 BMI associated loci and 207 variants (p < 10-4) influencing GWG, with the strongest association for rs9690213 in PODXL (p = 9.86E-07). In Analysis 3, among 648 GWG associated loci, 2091 variants were associated with BMI (FDR < 0.05). In Analysis 4, 7 variants in GWG associated loci influenced BMI in the ARIC cohort.

CONCLUSIONS

Here, we have shown that loci influencing BMI might have an impact on GWG and GWG associated loci might influence BMI, both in the general and T1DM cohorts. The results suggest that both phenotypes are related to insulin signaling, glucose homeostasis, mitochondrial metabolism, ubiquitinoylation and inflammatory responses.

Long Non-Coding RNAs (lncRNAs) in Cardiovascular Disease Complication of Type 2 Diabetes

The discovery of non-coding RNAs (ncRNAs) has opened a new paradigm to use ncRNAs as biomarkers to detect disease progression. Long non-coding RNAs (lncRNA) have garnered the most attention due to their specific cell-origin and their existence in biological fluids. Type 2 diabetes patients will develop cardiovascular disease (CVD) complications, and CVD remains the top risk factor for mortality. Understanding the lncRNA roles in T2D and CVD conditions will allow the future use of lncRNAs to detect CVD complications before the symptoms appear. This review aimed to discuss the roles of lncRNAs in T2D and CVD conditions and their diagnostic potential as molecular biomarkers for CVD complications in T2D.