Does an imbalance in circulating vascular endothelial growth factors (VEGFs) cause atrial fibrillation in patients with valvular heart disease?

Construction of atrial fibrillation-related circRNA/lncRNA-miRNA-mRNA regulatory network and analysis of potential biomarkers

BACKGROUND

The specific pathogenesis of atrial fibrillation (AF) remains unclear. In this study, we examined the expression of differential messenger RNAs (mRNAs), circular RNAs (circRNAs), and long-stranded noncoding RNAs (lncRNAs) from human peripheral blood mononuclear cells to initially construct a circRNA/lncRNA-miRNA-mRNA ceRNA regulatory network to explore the pathogenesis of AF and to screen for potential biomarkers.

METHODS

A total of four pairs of AF cases and healthy subjects were selected to detect differentially expressed mRNAs, circRNAs, and lncRNAs in peripheral blood mononuclear cells by microarray analysis. And 20 pairs of peripheral blood from AF patients and healthy subjects were selected for validation of mRNA, circRNA, and lncRNA by quantitative real-time PCR (qRT-PCR).The relevant ceRNA networks were constructed by GO and KEGG and correlation analysis.

RESULTS

The results showed that compared with healthy subjects, there were 813 differentially expressed mRNAs (DEmRNAs) in peripheral blood monocytes of AF, including 445 upregulated genes and 368 downregulated genes, 120 differentially expressed circRNAs (DEcircRNAs), including 65 upregulated and 55 downregulated, 912 differentially expressed lncRNAs (DElncRNAs), including 531 upregulated and 381 downregulated lncRNAs. GO and KEGG analysis of DERNA revealed the biological processes and pathways involved in AF. Based on microarray data and predicted miRNAs, a ceRNA network containing 34 mRNAs, 212 circRNAs, 108 lncRNAs, and 38 miRNAs was constructed.

CONCLUSION

We revealed a novel ceRNA network in AF and showed that downregulated XIST, circRNA_2773, and CADM1 were negatively correlated with miR-486-5p expression and had a potential targeting relationship with miR-486-5p.

Mechanisms of Quercetin against atrial fibrillation explored by network pharmacology combined with molecular docking and experimental validation

Atrial fibrillation (AF) is a common atrial arrhythmia for which there is no specific therapeutic drug. Quercetin (Que) has been used to treat cardiovascular diseases such as arrhythmias. In this study, we explored the mechanism of action of Que in AF using network pharmacology and molecular docking. The chemical structure of Que was obtained from Pubchem. TCMSP, Swiss Target Prediction, Drugbank, STITCH, Pharmmapper, CTD, GeneCards, DISGENET and TTD were used to obtain drug component targets and AF-related genes, and extract AF and normal tissue by GEO database differentially expressed genes by GEO database. The top targets were IL6, VEGFA, JUN, MMP9 and EGFR, and Que for AF treatment might involve the role of AGE-RAGE signaling pathway in diabetic complications, MAPK signaling pathway and IL-17 signaling pathway. Molecular docking showed that Que binds strongly to key targets and is differentially expressed in AF. In vivo results showed that Que significantly reduced the duration of AF fibrillation and improved atrial remodeling, reduced p-MAPK protein expression, and inhibited the progression of AF. Combining network pharmacology and molecular docking approaches with in vivo studies advance our understanding of the intensive mechanisms of Quercetin, and provide the targeted basis for clinical Atrial fibrillation treatment.

Correlation analysis of survivin, ING4, CXCL8 and VEGF expression in prostate cancer tissue

OBJECTIVE

This study aimed to investigate the expression of Survivin, inhibitor of growth 4 (ING4), CXC chemokine ligand 8 (CXCL8), vascular endothelial growth factor (VEGF), and the correlation between Survivin, ING4, CXCL8 and VEGF in prostate cancer (PCa) tissues.

METHODS

From January 2019 to December 2019, 51 patients from Chengwu People's Hospital and The First People's Hospital of Taian, with PCa were selected as the PCa group and 47 patients with benign prostatic hyperplasia (BPH) were included as the BPH group. The expression of Survivin, ING4, CXCL8 and VEGF in both groups and among patients with different clinical stages in the PCa group were compared, and the correlation between Survivin, ING4, CXCL8 and VEGF expression in PCa tissues was analyzed.

RESULTS

Survivin, ING4, CXCL8, and VEGF expression differed significantly between the two groups (P<0.05). The Survivin positive expression rate, CXCL8 positive expression rate, and VEGF positive expression rate in the PCa group were significantly higher than those in the BPH group (P<0.05), and ING4 positive expression rate in the PCa group was significantly lower than that in the BPH group (P<0.05). Survivin positive expression rate, CXCL8 positive expression rate, and VEGF positive expression rate were significantly higher in PCa patients with stage III+IV than those of stage I+II (P<0.05), and ING4 positive expression rate in PCa patients in stage III+IV was significantly lower than that in stage I+II (P<0.05). Kendall's tau-b analysis, VEGF was positively correlated with Survivin and CXCL8 (P<0.05) and negatively correlated with ING4 (P<0.05) in PCa tissues.

CONCLUSION

Survivin, CXCL8, and VEGF were highly expressed and ING4 was lowly expressed in PCa tissues, which was correlated with clinical stage; additionally, Survivin, ING4, CXCL8, and VEGF played a synergistic role with each other in the development and progression of PCa.

Vascular endothelial growth factor modulates pulmonary vein arrhythmogenesis via vascular endothelial growth factor receptor 1/NOS pathway

Atrial fibrillation (AF) is a common form of arrhythmia with serious public health impacts, but its underlying mechanisms are not yet fully understood. Vascular endothelial growth factor (VEGF) is highly expressed in the atrium of patients with AF, but whether VEGF affects AF pathogenesis remains unclear. Pulmonary veins (PVs) are important sources for the genesis of atrial tachycardia or AF. Therefore, this study assessed the effects of VEGF on PV electrophysiological properties and evaluated its underlying mechanisms. Conventional microelectrodes and whole-cell patch clamps were performed using isolated rabbit PV preparations or single isolated PV cardiomyocytes before and after VEGF or VEGF receptor (VEGFR), Akt, NOS inhibitor administration. We found that VEGF (0.1, 1, and 10 ng/mL) reduced the PV beating rate in a dose-dependent manner. Furthermore, VEGF (10 ng/mL) reduced late diastolic depolarization and diastolic tension. Isoproterenol increased PV beating and burst firing, which was attenuated by VEGF (1 ng/mL). In the presence of VEGFR-1 inhibition (ZM306416 at 10 μM) and L-NAME (100 μM), VEGF (1 ng/mL) did not alter PV spontaneous activity. In isolated PV cardiomyocytes, VEGF (1 ng/mL) decreased L-type calcium, sodium/calcium exchanger, and late sodium currents. In conclusion, we found that VEGF reduces PV arrhythmogenesis by modulating sodium/calcium homeostasis through VEGFR-1/NOS signaling pathway.

Atrial fibrillation: the role of hypoxia-inducible factor-1-regulated cytokines

Atrial fibrillation (AF) is a common arrhythmia that has major morbidity and mortality. Hypoxia plays an important role in AF initiation and maintenance. Hypoxia-inducible factor (HIF), the master regulator of oxygen homeostasis in cells, plays a fundamental role in the regulation of multiple chemokines and cytokines that are involved in different physiological and pathophysiological pathways. HIF is also involved in the pathophysiology of AF induction and propagation mostly through structural remodeling such as fibrosis; however, some of the cytokines discussed have even been implicated in electrical remodeling of the atria. In this article, we highlight the association between HIF and some of its related cytokines with AF. Additionally, we provide an overview of the potential diagnostic benefits of using the mentioned cytokines as AF biomarkers. Research discussed in this review suggests that the expression of these cytokines may correlate with patients who are at an increased risk of developing AF. Furthermore, cytokines that are elevated in patients with AF can assist clinicians in the diagnosis of suspect paroxysmal AF patients. Interestingly, some of the cytokines have been elevated specifically when AF is associated with a hypercoagulable state, suggesting that they could be helpful in the clinician's and patient's decision to begin anticoagulation. Finally, more recent research has demonstrated the promise of targeting these cytokines for the treatment of AF. While still in its early stages, tools such as neutralizing antibodies have proved to be efficacious in targeting the HIF pathway and treating or preventing AF.

Antibody microarray analysis of serum inflammatory cytokines in patients with calcific aortic valve disease

Background

Calcific aortic valve disease (CAVD) is a slowly progressive pathologic process associated with significant morbidity and mortality, CAVD is the most common valve heart disease in the elderly and a leading cause of aortic valve stenosis. Multiple steps characterize the process: inflammation, cell apoptosis, lipid deposition, renin-angiotensin system activation, extracellular matrix remodeling, and bone formation. This paper focuses on detecting and analyzing the expression of serum inflammatory factors in CAVD by antibody microarray techniques.

Methods

In this study, a total of 258 patients were included at Tianjin Chest Hospital between January 2017 and December 2018, subjects were divided into three groups: control, coronary artery disease (CAD), and CAVD. Blood samples were collected, and adipokine/cytokine/chemokine serum profiles were measured by antibody arrays.

Results

These data suggest that B-Lymphocyte Chemoattractant (BLC), Interleukin (IL)-12p40, monokine inducible by γ interferon (MIG), and Macrophage inflammatory protein (MIP)-1delta were significantly increased in CAVD compared to control or CAD. Furthermore, Real-time quantified PCR, Western blot assay, and Flow cytometer detection showed that these four cytokines/chemokines were from peripheral blood mononuclear cells.

Conclusions

These findings suggest that BLC, IL-12p40, MIG, and MIP-1delta can be used as a marker to assess CAVD, which could have significant clinical implications.