DACT2 regulates structural and electrical atrial remodeling in atrial fibrillation

sVEGFR3 alleviates myocardial ischemia/reperfusion injury through regulating mitochondrial homeostasis and immune cell infiltration

Recent studies have suggested that sVEGFR3 is involved in cardiac diseases by regulating lymphangiogenesis; however, results are inconsistent. The aim of this study was to investigate the function and mechanism of sVEGFR3 in myocardial ischemia/reperfusion injury (MI/RI). sVEGFR3 effects were evaluated in vivo in mice subjected to MI/RI, and in vitro using HL-1 cells exposed to oxygen-glucose deprivation/reperfusion. Echocardiography, TTC-Evans blue staining, ELISA, electron microscopy, immunofluorescence, western blotting, and flow cytometry were used to investigate whether sVEGFR3 attenuates I/R injury. Transcriptome sequencing was used to investigate the downstream mechanism of sVEGFR3. Results showed that, in vivo, sVEGFR3 pretreatment reduced cardiac dysfunction, infarct area, and myocardial injury indicators by reducing ROS production, AIF expression, and apoptosis. In vitro, sVEGFR3 restored mitochondrial homeostasis by stabilizing the mitochondrial membrane potential (MMP) and preventing the opening of mitochondrial permeability transition pores (mPTP). And sVEGFR3 inhibits mitochondrial apoptosis through the Ras/MEK/ERK pathway. Furthermore, I/R injury increased the proportion of M1 macrophages and CD4 + T cells in myocardial tissue, as well as serum IFN-γ and TNF-α levels, whereas sVEGFR3 treatment attenuated these effects. sVEGFR3 attenuates MI/RI by regulating mitochondrial homeostasis and immune cell infiltration, and reduces intrinsic ROS-mediated mitochondrial apoptosis via the Ras/MEK/ERK pathway.

DACT2 modulates atrial fibrillation through TGF/β and Wnt signaling pathways

Atrial fibrillation (AF) is a common cardiac arrhythmia that seriously affects the quality of life of patients. Effective treatment and prevention are important to control the morbidity and mortality of AF. It has been found that cardiac fibrosis promotes the onset and progression of AF. It is now known that transforming growth factor β (TGF-β), an important fibrotic cytokine, plays an important role in cardiac fibrosis by inducing myofibroblast activation via the activation of classical (SMAD-based) and non-classical (non-SMAD-based) signaling pathways. In addition, specific activation of the Wnt/β-catenin pathway has been shown to promote the transformation of fibroblasts into myofibroblasts. In recent years, a new family of proteins, namely Disheveled-associated antagonist of beta-catenin (DACT) 2, can affect the Wnt/β-catenin and TGF-β signaling pathways by regulating the phosphorylation levels of these target proteins, which in turn affects the progression of fibrosis. The present study focuses on the effect of DACT2-guided β-catenin on atrial fibrosis. It is expected that the summarized information can be helpful in the treatment of AF.

DACT2 protects against pulmonary fibrosis via suppressing glycolysis in lung myofibroblasts

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive fibrotic lung disease with poor prognosis and few treatment options. Dapper homolog 2 (DACT2), a member of the DACT gene family, plays crucial roles in tissue development and injury. However, its functions and molecular mechanisms in IPF remain largely unknown. We aimed to investigate the role of DACT2 in the development of pulmonary fibrosis and the therapeutic potential of targeting DACT2 related signaling pathways.

METHODS

In our study, adeno-associated virus serotype 6 (AAV6)-mediated DACT2 overexpression was assessed in several mice models of experimental pulmonary fibrosis in vivo. The role of DACT2 in lung myofibroblast differentiation was determined by DACT2 overexpression in vitro. The glucose uptake, extracellular acidification rate, intracellular adenosine-triphosphate (ATP) level and lactate levels of myofibroblasts were detected after DACT2 overexpression. The LDHA degradation rate and colocalization with lysosomes were monitored as well.

RESULTS

Intratracheal administration of AAV6-mediated DACT2 overexpression apparently attenuated pulmonary fibrosis in experimental pulmonary fibrosis models. In vitro experiments revealed that DACT2 inhibited TGF-β-induced myofibroblast differentiation by promoting lysosome-mediated LDHA degradation and thus suppressing glycolysis in myofibroblasts.

CONCLUSION

In conclusion, our findings support for DACT2 as a novel pharmacological target for pulmonary fibrosis treatments.

Identification of candidate biomarkers and therapeutic agents for heart failure by bioinformatics analysis

INTRODUCTION

Heart failure (HF) is a heterogeneous clinical syndrome and affects millions of people all over the world. HF occurs when the cardiac overload and injury, which is a worldwide complaint. The aim of this study was to screen and verify hub genes involved in developmental HF as well as to explore active drug molecules.

METHODS

The expression profiling by high throughput sequencing of GSE141910 dataset was downloaded from the Gene Expression Omnibus (GEO) database, which contained 366 samples, including 200 heart failure samples and 166 non heart failure samples. The raw data was integrated to find differentially expressed genes (DEGs) and were further analyzed with bioinformatics analysis. Gene ontology (GO) and REACTOME enrichment analyses were performed via ToppGene; protein-protein interaction (PPI) networks of the DEGs was constructed based on data from the HiPPIE interactome database; modules analysis was performed; target gene-miRNA regulatory network and target gene-TF regulatory network were constructed and analyzed; hub genes were validated; molecular docking studies was performed.

RESULTS

A total of 881 DEGs, including 442 up regulated genes and 439 down regulated genes were observed. Most of the DEGs were significantly enriched in biological adhesion, extracellular matrix, signaling receptor binding, secretion, intrinsic component of plasma membrane, signaling receptor activity, extracellular matrix organization and neutrophil degranulation. The top hub genes ESR1, PYHIN1, PPP2R2B, LCK, TP63, PCLAF, CFTR, TK1, ECT2 and FKBP5 were identified from the PPI network. Module analysis revealed that HF was associated with adaptive immune system and neutrophil degranulation. The target genes, miRNAs and TFs were identified from the target gene-miRNA regulatory network and target gene-TF regulatory network. Furthermore, receiver operating characteristic (ROC) curve analysis and RT-PCR analysis revealed that ESR1, PYHIN1, PPP2R2B, LCK, TP63, PCLAF, CFTR, TK1, ECT2 and FKBP5 might serve as prognostic, diagnostic biomarkers and therapeutic target for HF. The predicted targets of these active molecules were then confirmed.

CONCLUSION

The current investigation identified a series of key genes and pathways that might be involved in the progression of HF, providing a new understanding of the underlying molecular mechanisms of HF.

WNT signaling in atrial fibrillation

The Wnt signaling pathway regulates physiological processes such as cell proliferation and differentiation, cell fate decisions, and stem cell maintenance and, thus, plays essential roles in embryonic development, but also in adult tissue homeostasis and repair. The Wnt signaling pathway has been associated with heart development and repair and has been shown to be crucially involved in proliferation and differentiation of progenitor cells into cardiomyocytes. The investigation of the role of the Wnt signaling pathway and the regulation of its expression/activity in atrial fibrillation has only just begun. The present minireview (I) provides original data regarding the expression of Wnt signaling components in atrial tissue of patients with atrial fibrillation or sinus rhythm and (II) summarizes the current state of knowledge of the regulation of Wnt signaling components' expression/activity and the contribution of the various levels of the Wnt signal transduction pathway to the processes of the development, maintenance, and progression of atrial fibrillation.