Identification of vital modules and genes associated with heart failure based on weighted gene coexpression network analysis.

AIMS: Heart failure (HF) is a chronic heart disease with a high incidence and mortality. Due to the regulatory complexity of gene coexpression networks, the underlying hub genes regulation in HF remain incompletely appreciated. We aimed to explore potential key modules and genes for HF using weighted gene coexpression network analysis (WGCNA). METHODS AND RESULTS: The expression profiles by high throughput sequencing of heart tissues samples from HF and non-HF samples were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between HF and non-HF samples were firstly identified. Then, a coexpression network was constructed to identify key modules and potential hub genes. The biological functions of potential hub genes were analysed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Finally, a protein-protein interaction (PPI) network was constructed using the STRING online tool. A total of 135 DEGs (133 up-regulated and 2 down-regulated DEGs) between HF and non-HF samples were identified in the GSE135055 and GSE123976 datasets. Moreover, a total of 38 modules were screened based on WGCNA in the GSE135055 dataset, and six potential hub genes (UCK2, ASB1, CCNI, CUX1, IRX6, and STX16) were screened from the key module by setting the gene significance over 0.2 and the module membership over 0.8. Furthermore, 78 potential hub genes were obtained by taking the intersection of the 135 DEGs and all genes in the key module, and enrichment analysis revealed that they were mainly involved in the MAPK and PI3K-AKT signalling pathways. Finally, in a PPI network constructed with the 78 potential hub genes, CUX1 and ASB1 were identified as hub genes in HF because they were also identified as potential hub genes in the WGCNA. CONCLUSIONS: To the best of our knowledge, our study is the first to employ WGCNA to identify the key module and hub genes for HF. Our study identified a module and two genes that might play important roles in HF, which may provide potential biomarkers for the diagnosis of HF and improve our knowledge of the molecular mechanisms underlying HF.

Targeting the KCa3.1 channel suppresses diabetes-associated atherosclerosis via the STAT3/CD36 axis.

BACKGROUND: In diet-induced arterial atherosclerosis, increased KCa3.1 channel was associated with atherosclerotic plaque progression and instability. Macrophages are involved in the formation of atherosclerotic plaques, and the release of inflammatory cytokines and oxygen free radicals promotes plaque progression. However, whether the macrophage KCa3.1 channel facilitates diabetes-accelerated atherosclerosis is still unclear. This study investigated atherosclerotic plaque in ApoE-/- mice regulated by the KCa3.1 channel. METHODS AND RESULTS: In vivo, blocking KCa3.1channel inhibit the development of the atherosclerotic lesion in diabetic ApoE-/- mice fed with a high-fat diet. In vitro, upregulation of KCa3.1 channel level occurred in RAW264.7 cells treated with HG plus ox-LDL in a time-dependent manner. Blocking KCa3.1 significantly reduced the uptake of ox-LDL in mice peritoneal macrophages. Further studies indicated the KCa3.1 siRNA and TRAM-34 (KCa3.1 inhibitor) attenuated the scavenger receptor CD36 expression via inhibiting STAT3 phosphorylation. CONCLUSION: Blockade of macrophage KCa3.1 channel inhibit cellular oxidized low-density lipoprotein accumulation and decrease proinflammation factors expression via STAT3/CD36 axis. This study provided a novel therapeutic target to reduce the risk of atherosclerosis development in diabetic patients.

Comprehensive analysis of the ceRNA network in coronary artery disease.

With the rapid aging of the population, coronary artery disease (CAD) has become one of the most fatal chronic diseases. However, the genetic mechanism of CAD is still unclear. The purpose of this study is to construct the lncRNA-miRNA-mRNA regulatory network for CAD diseases and systematically identify differentially expressed genes in patients with coronary heart disease. In this study, two lncRNA datasets (GSE69587 and GSE113079) and a microRNA dataset (GSE105449) which contained 393 and 38 CAD samples were selected. In addition, two mRNA datasets which named GSE113079 (98 CAD samples) and GSE9820 (8 CAD samples) were selected to search the differentially expressed genes (DEGs). By comparing the expression data between CAD and control samples, a total of 1111 lncRNAs, 2595 mRNAs and 22 miRNAs were identified. Based on the DEGs, a lncRNA-miRNA-mRNA ceRNA network was constructed to explore the hub nodes in CAD. In the ceRNA network, the lncRNAs KCNQ1OT1 and H19 showed high connectivity with the nine miRNAs. GO and KEGG results showed that genes in ceRNA networks were mainly involved in nitrogen compound metabolic process, PI3K-Akt signaling pathway and retrograde endocannabinoid signaling. These findings will improve the understanding of the occurrence and development mechanism of CAD.

Knockout of AKAP150 improves impaired BK channel-mediated vascular dysfunction through the Akt/GSK3ß signalling pathway in diabetes mellitus.

Vascular dysfunction resulting from diabetes is an important factor in arteriosclerosis. Previous studies have shown that during hyperglycaemia and diabetes, AKAP150 promotes vascular tone enhancement by intensifying the remodelling of the BK channel. However, the interaction between AKAP150 and the BK channel remains open to discussion. In this study, we investigated the regulation of impaired BK channel-mediated vascular dysfunction in diabetes mellitus. Using AKAP150 null mice (AKAP150-/- ) and wild-type (WT) control mice (C57BL/6J), diabetes was induced by intraperitoneal injection of streptozotocin. We found that knockout of AKAP150 reversed vascular remodelling and fibrosis in mice with diabetes and in AKAP150-/- diabetic mice. Impaired Akt/GSK3ß signalling contributed to decreased BK-ß1 expression in aortas from diabetic mice, and the silencing of AKAP150 increased Akt phosphorylation and BK-ß1 expression in MOVAS cells treated with HG medium. The inhibition of Akt activity caused a decrease in BK-ß1 expression, and treatment with AKAP150 siRNA suppressed GSK3ß expression in the nuclei of MOVAS cells treated with HG. Knockout of AKAP150 reverses impaired BK channel-mediated vascular dysfunction through the Akt/GSK3ß signalling pathway in diabetes mellitus.

Effect of BIN1 on cardiac dysfunction and malignant arrhythmias.

Heart failure (HF) is the end-stage syndrome for most cardiac diseases, and the 5-year morbidity and mortality of HF remain high. Malignant arrhythmia is the main cause of sudden death in the progression of HF. Recently, bridging integrator 1 (BIN1) was discovered as a regulator of transverse tubule function and calcium signalling in cardiomyocytes. BIN1 downregulation is linked to abnormal cardiac contraction, and it increases the possibility of malignant arrhythmias preceding HF. Because of the detectability of cardiac BIN1 in peripheral blood, BIN1 may serve as a predictor of HF and may be useful in therapy development. However, the mechanism of BIN1 downregulation in HF and how BIN1 regulates normal cardiac function under physiological conditions remain unclear. In this review, recent progress in the biological studies of BIN1-related cardiomyocytes and the effect of cardiac dysfunction and malignant arrhythmia will be discussed.

Cardiac function modulation depends on the A-kinase anchoring protein complex.

The A-kinase anchoring proteins (AKAPs) are a group of structurally diverse proteins identified in various species and tissues. These proteins are able to anchor protein kinase and other signalling proteins to regulate cardiac function. Acting as a scaffold protein, AKAPs ensure specificity in signal transduction by enzymes close to their appropriate effectors and substrates. Over the decades, more than 70 different AKAPs have been discovered. Accumulative evidence indicates that AKAPs play crucial roles in the functional regulation of cardiac diseases, including cardiac hypertrophy, myofibre contractility dysfunction and arrhythmias. By anchoring different partner proteins (PKA, PKC, PKD and LTCCs), AKAPs take part in different regulatory pathways to function as regulators in the heart, and a damaged structure can influence the activities of these complexes. In this review, we highlight recent advances in AKAP-associated protein complexes, focusing on local signalling events that are perturbed in cardiac diseases and their roles in interacting with ion channels and their regulatory molecules. These new findings suggest that AKAPs might have potential therapeutic value in patients with cardiac diseases, particularly malignant rhythm.

Critical regulation of atherosclerosis by the KCa3.1 channel and the retargeting of this therapeutic target in in-stent neoatherosclerosis.

Coronary heart disease is a serious cardiovascular illness. Percutaneous coronary artery stent implantation has become a routine way to treat coronary heart disease. Although studies have shown how a drug-eluting stent could improve the efficacy of clinical treatment, 10~20% of in-stent restenosis is still an important outcome that restricts the clinical efficacy of drug-eluting stent implantations and causes cardiovascular events such as angina pectoris, acute myocardial infarction, and sudden death. The KCa3.1 channel plays an important role in neoatherosclerosis of in-stent restenosis by regulating macrophage function. Recent studies have shown that the KCa3.1 channel, which belongs to the family of calcium-activated potassium channels, plays an important role in the occurrence and development of various inflammatory diseases by regulating cell membrane potentials and calcium signaling in the processes of macrophage migration and mitogen-stimulated vascular smooth muscle cell and fibroblast proliferation. The KCa3.1 channel is activated by elevated intracellular calcium levels. Inhibition of the KCa3.1 channel can effectively slow the progression of arterial plaque rupture and reduce the degree of vascular restenosis, and so substances that can carry out this inhibition are expected to become targeted drugs for the treatment of in-stent neoatherosclerosis. This article reviews the pathological and physiological roles of the KCa3.1 channel and its roles in the disease prognosis of in-stent neoatherosclerosis.

MicroRNA­mRNA integrated analysis based on a case of well­differentiated thyroid cancer with both metastasis and metastatic recurrence.

The incidence of well­differentiated thyroid cancer (WDTC) is rapidly increasing. Poor survival follows distant metastasis (DM) and recurrence. In the present study, we aimed to analyze the expression alterations in different stages of WDTC and the regulatory mechanism of DM and the recurrence of DM. A male patient diagnosed with follicular thyroid cancer and distant metastasis in the eleventh thoracic vertebrae received total thyroidectomy and the removal of a metastatic lesion. A local relapse was found in the vertebrae after four­time iodine­131 treatment. We performed mRNA and microRNA microarray on the paracancerous, cancerous, metastatic and metastatic recurrent tissue. In combination with the data of The Cancer Genome Atlas (TCGA), we used bioinformatics approaches to analyze the common alterations and microRNA­mRNA interactions among the processes of tumorigenesis and metastasis. Metastatic lesions and recurrent lesions were used to investigate the molecular mechanism of tumor evolution and recurrence in this case. A total of four mRNAs and two microRNAs were newly found to be related to patient survival in WDTC. The microRNA­mRNA interactions were predicted for the overlapped mRNAs and microRNAs. Lineage deregulation of genes, such as C­X­C motif chemokine receptor 4 (CXCR4) and thyroglobulin (TG) were found from the tumorigenic stage to the metastatic stage. The ribosome pathway was highly enriched in the bone metastasis compared with the cancerous tissue. The downstreaming effects of p53 were impaired in the recurrent lesion due to deregulation of several functional genes. The integrated analysis with TCGA data indicated several prognostic markers and regulatory networks for potential treatment. Our results also provided possible molecular mechanisms in which the ribosome and p53 pathways may respectively contribute to bone metastasis and local recurrence of metastasis.

Curcumin downregulates the expression of Snail via suppressing Smad2 pathway to inhibit TGF-ß1-induced epithelial-mesenchymal transitions in hepatoma cells.

Hepatocellular carcinoma (HCC) remains the third cause of cancer-related mortality. Resection and transplantation are the only curative treatments available but are greatly hampered by high recurrence rates and development of metastasis, the initiation of cancer metastasis requires migration and invasion of cells, which is enabled by epithelial-mesenchymal transitions (EMT). TGF-ß1 is a secreted protein that performs many cellular functions, including the control of cell growth, cell proliferation, cell differentiation and apoptosis. TGF-ß1 is known as a major inducer of EMT, and it was reported that TGF-ß1 induced EMT via Smad-dependent and Smad-independent pathways. However, the extrinsic signals of TGF-ß1 regulated the EMT in hepatoma cells remains to be elucidated, and searching drugs to inhibit TGF-ß1 induced EMT may be considered to be a potentially effective therapeutic strategy in HCC. Fortunately, in this study, we found that curcumin inhibited TGF-ß1-induced EMT in hepatoma cells. Furthermore, we demonstrated that curcumin inhibited TGF-ß1-induced EMT via inhibiting Smad2 phosphorylation and nuclear translocation, then suppressing Smad2 combined with the promoter of Snail which inhibited the transcriptional expression of Snail. These findings suggesting curcumin could be a useful agent for antitumor therapy and also a promising drug combined with other strategies to preventing and treating HCC.

[Cloning and expression of the succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum Chinese strain in E. coli].

OBJECTIVE: To clone the full-length gene encoding succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum (SjSDISP) Chinese strain and express it in Escherichia coli. METHODS: According to the published incomplete EST (BU804141) of SjSDISP and the sequence of multiclone sites of lambda gt11 vector, 2 pairs of primers were designed and synthesized. Then the 3' and 5'ends of the EST of the SjSDISP from adult Schistosoma japonicum cDNA library were amplified by anchored PCR. After sequencing, a full-length cDNA sequence of the SjSDISP was obtained, and then it was cloned into prokaryotic expression vector pGEX-4T-1. Identified by agarosed gel electrophoresis, endonucleases digestion and PCR, the resultant recombinant plasmid was used for the expression under the temperature-dependent condition and Western blot analysis. RESULTS: A 1,071 bp sequence was obtained. Sequence analysis showed that the fragment contained a complete open reading frame (ORF), encoding 278 amino acid residues. This target fragment was cloned into the prokaryotic expression vector pGEX-4T-1, and expressed in Escherichia coli. SDS-PAGE revealed that the molecular weight of the expressed fusion recombinant product was 56 kD. Western blot showed that the recombinant protein was recognized by polyclonal rabbit antiserum immunized with Schistosoma japonicum adult worm antigen. CONCLUSION: Cloning of the full-length gene encoding SjSDISP and its bacterial expression were successfully done.