Role of miRNAs in Epicardial Adipose Tissue in CAD Patients with T2DM

Profiling of Non-Coding Regulators and Their Targets in Epicardial Fat from Patients with Coronary Artery Disease

Epicardial fat is a continuously growing target of investigation in cardiovascular diseases due to both its anatomical proximity to the heart and coronary circulation and its unique physiology among adipose depots. Previous reports have demonstrated that epicardial fat plays key roles in coronary artery disease, but the non-coding RNA and transcriptomic alterations of epicardial fat in coronary artery disease have not been investigated thoroughly. Micro- and lncRNA microarrays followed by GO-KEGG functional enrichment analysis demonstrated sex-dependent unique mi/lncRNAs altered in human epicardial fat in comparison to subcutaneous fat in both patients with and without coronary artery disease (IRB approved). Among the 14 differentially expressed microRNAs in epicardial fat between patients with and without coronary artery disease, the hsa-miR-320 family was the most highly represented. IPW lncRNA interacted with three of these differentially expressed miRNAs. Next-generation sequencing and pathway enrichment analysis identified six unique mRNAs–miRNA pairs. Pathway enrichment identified inflammation, adipogenesis, and cardiomyocyte apoptosis as the most represented functions altered by the mi/lncRNAs and atherosclerosis and myocardial infarction among the highest cardiovascular pathologies associated with them. Overall, the epicardial fat in patients with coronary artery disease has a unique mi/lncRNA profile which is sex-dependent and has potential implications for regulating cardiac function.

Integrated analysis of transcriptome profiling of lncRNAs and mRNAs in livers of type 2 diabetes mellitus

Long noncoding RNAs (lncRNAs) influence the progression of almost all human diseases, but the participation of lncRNAs in type 2 diabetes mellitus (T2DM) has not been fully elucidated. The present study aimed to systematically compare the transcriptome profiling of lncRNAs and mRNAs in livers between T2DM patients and controls, to identify key genes associated with T2DM pathogenesis, and to predict the underlying molecular mechanisms. As a result, a total of 1,512 differentially expressed (DE) lncRNAs and 1,923 DE mRNAs were identified through microarray analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that multiple metabolic processes were dysregulated such as small molecule, organic acid, lipid and branched chain amino acid metabolism. Protein-protein interaction network was constructed and 10 hub mRNAs were identified, including EHHADH, ATM, ACOX1, PIK3R1, EGFR, UQCRFS1, HMGCL, UQCRC2, NDUFS3 and F2. RT-qPCR was conducted to verify the validity of microarray results. Then, coding-noncoding co-expression network and competing endogenous RNA (ceRNA) network were analyzed to predict the lncRNA-mRNA and lncRNA-miRNA-mRNA regulatory patterns. Subsequently, 10 key intermediating miRNAs in ceRNA networks with a node degree > 80 were identified, including hsa-miR-5692a, hsa-miR-12136, hsa-miR-5680, hsa-miR-1305, hsa-miR-6833-5p, hsa-miR-7159-5p, hsa-miR-548as-3p, hsa-miR-6873-3p, hsa-miR-1290 and hsa-miR-4768-5p. In conclusion, the present study evaluated the transcriptome profiling of lncRNAs and mRNAs in livers from T2DM patients, with a value for understanding the molecular mechanism of disease pathogenesis and identifying effective biomarkers in clinical diagnosis.

Expression profiles of long noncoding and messenger RNAs in epicardial adipose tissue derived from patients with coronary atherosclerosis

BACKGROUND

Given its close anatomical location to the heart and its endocrine properties, attention on epicardial adipose tissue (EAT) has increased.

OBJECTIVE

This study investigated the expression profiles of long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) in EAT derived from patients with coronary artery disease (CAD).

METHODS

EAT samples from 8 CAD and 8 non-CAD patients were obtained during open-heart surgery. The expression of lncRNAs and mRNAs in each EAT sample was investigated using microarray analysis and further verified using reverse transcription-quantitative polymerase chain reaction.

RESULTS

Overall, 1,093 differentially expressed mRNAs and 2,282 differentially expressed lncRNAs were identified in EAT from CAD vs non-CAD patients. Analysis using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes showed that these differentially expressed genes were mainly enriched in various inflammatory, immune, and metabolic processes. They were also involved in osteoclast differentiation, B cell receptor and adipocytokine signaling, and insulin resistance pathways. Additionally, lncRNA-mRNA and lncRNA-target pathway networks were built to identify potential core genes (e.g. Lnc-CCDC68-2:1, AC010148.1, NONHSAT104810) involved in atherosclerosis pathogenesis.

CONCLUSION

In summary, lncRNA and mRNA profiles in EAT were markedly different between CAD and non-CAD patients. Our study identifies several potential key genes and pathways that may participate in atherosclerosis development.

PDGF-BB promotes vascular smooth muscle cell migration by enhancing Pim-1 expression via inhibiting miR-214

Background

Several studies have indicated that the platelet-derived growth factor/platelet-derived growth factor receptor (PDGF/PDGFR) pathway is involved in the process of atherosclerosis. However, its underlying mechanism remains to be further elucidated. Serine/threonine-protein kinase pim-1 (Pim-1), a member of serine/threonine-specific kinases, is a pro-oncogene published to be related to cell proliferation, apoptosis, and metastasis of cancer cells. Whether Pim-1 is involved in PDGF/PDGFR pathway-mediated coronary atherosclerotic heart disease remains to be elucidated.

Methods

We established a cell model of PDGF-BB-stimulated smooth muscle cells using A7r5 cells. Transwell assay was used to detect the potential of cell migration and invasion. The targeted regulation of Pim-1 by miR-214 was confirmed by luciferase assay. Rescue experiments were performed to determine the role of the PDGF-BB/miR-214/Pim-1 axis on the cell migration of smooth muscle cells by including PDGF-BB treatment, and the overexpression of miR-214 and Pim-1. Quantitative polymerase chain reaction (qPCR) was used to examine the gene expression and western blot was performed to detect the protein expression.

Results

Our data indicated that PDGF-BB could effectively enhance smooth muscle cell migration. We also showed Pim-1 was a target of miR-214 in A7r5 cells. The expression of Pim-1 was shown to be upregulated by PDGF-BB via suppression of the expression of miR-214. Moreover, overexpression miR-214 inhibited PDGF-BB-stimulated Pim-1 expression and smooth muscle cell migration via modulating epithelial-mesenchymal transition (EMT), but no change on cell cycle. However, overexpression of Pim-1 reversed miR-214-blocked cell migration by promoting the activation of the STAT3, AKT, and ERK signaling pathways.

Conclusions

Our data suggested that the PDGF/miR-214/Pim-1 axis could be a potential target for coronary atherosclerotic heart disease.

The Sick Adipose Tissue: New Insights Into Defective Signaling and Crosstalk With the Myocardium

Adipose tissue (AT) biology is linked to cardiovascular health since obesity is associated with cardiovascular disease (CVD) and positively correlated with excessive visceral fat accumulation. AT signaling to myocardial cells through soluble factors known as adipokines, cardiokines, branched-chain amino acids and small molecules like microRNAs, undoubtedly influence myocardial cells and AT function via the endocrine-paracrine mechanisms of action. Unfortunately, abnormal total and visceral adiposity can alter this harmonious signaling network, resulting in tissue hypoxia and monocyte/macrophage adipose infiltration occurring alongside expanded intra-abdominal and epicardial fat depots seen in the human obese phenotype. These processes promote an abnormal adipocyte proteomic reprogramming, whereby these cells become a source of abnormal signals, affecting vascular and myocardial tissues, leading to meta-inflammation, atrial fibrillation, coronary artery disease, heart hypertrophy, heart failure and myocardial infarction. This review first discusses the pathophysiology and consequences of adipose tissue expansion, particularly their association with meta-inflammation and microbiota dysbiosis. We also explore the precise mechanisms involved in metabolic reprogramming in AT that represent plausible causative factors for CVD. Finally, we clarify how lifestyle changes could promote improvement in myocardiocyte function in the context of changes in AT proteomics and a better gut microbiome profile to develop effective, non-pharmacologic approaches to CVD.

Differential epigenetic factors in the prediction of cardiovascular risk in diabetic patients

Hyperglycaemia can strongly alter the epigenetic signatures in many types of human vascular cells providing persistent perturbations of protein–protein interactions both in micro- and macro-domains. The establishment of these epigenetic changes may precede cardiovascular (CV) complications and help us to predict vascular lesions in diabetic patients. Importantly, these epigenetic marks may be transmitted across several generations (transgenerational effect) and increase the individual risk of disease. Aberrant DNA methylation and imbalance of histone modifications, mainly acetylation and methylation of H3, represent key determinants of vascular lesions and, thus, putative useful biomarkers for prevention and diagnosis of CV risk in diabetics. Moreover, a differential expression of some micro-RNAs (miRNAs), mainly miR-126, may be a useful prognostic biomarker for atherosclerosis development in asymptomatic subjects. Recently, also environmental-induced chemical perturbations in mRNA (epitranscriptome), mainly the N⁶-methyladenosine, have been associated with obesity and diabetes. Importantly, reversal of epigenetic changes by modulation of lifestyle and use of metformin, statins, fenofibrate, and apabetalone may offer useful therapeutic options to prevent or delay CV events in diabetics increasing the opportunity for personalized therapy. Network medicine is a promising molecular-bioinformatic approach to identify the signalling pathways underlying the pathogenesis of CV lesions in diabetic patients. Moreover, machine learning tools combined with tomography are advancing the individualized assessment of CV risk in these patients. We remark the need for combining epigenetics and advanced bioinformatic platforms to improve the prediction of vascular lesions in diabetics increasing the opportunity for CV precision medicine.

Integration of Gene Expression Profile Data of Human Epicardial Adipose Tissue from Coronary Artery Disease to Verification of Hub Genes and Pathways

Background

This study aim to identify the core pathogenic genes and explore the potential molecular mechanisms of human coronary artery disease (CAD).

Methodology

Two gene profiles of epicardial adipose tissue from CAD patients including GSE 18612 and GSE 64554 were downloaded and integrated by R software packages. All the coexpression of deferentially expressed genes (DEGs) were picked out and analyzed by DAVID online bioinformatic tools. In addition, the DEGs were totally typed into protein-protein interaction (PPI) networks to get the interaction data among all coexpression genes. Pictures were drawn by cytoscape software with the PPI networks data. CytoHubba were used to predict the hub genes by degree analysis. Finally all the top 10 hub genes and prediction genes in Molecular complex detection were analyzed by Gene ontology and Kyoto encyclopedia of genes and genomes pathway analysis. qRT-PCR were used to identified all the 10 hub genes.

Results

The top 10 hub genes calculated by the degree method were AKT1, MYC, EGFR, ACTB, CDC42, IGF1, FGF2, CXCR4, MMP2 and LYN, which relevant with the focal adhesion pathway. Module analysis revealed that the focal adhesion was also acted an important role in CAD, which was consistence with cytoHubba. All the top 10 hub genes were verified by qRT-PCR which presented that AKT1, EGFR, CDC42, FGF2, and MMP2 were significantly decreased in epicardial adipose tissue of CAD samples (p < 0.05) and MYC, ACTB, IGF1, CXCR4, and LYN were significantly increased (p < 0.05).

Conclusions

These candidate genes could be used as potential diagnostic biomarkers and therapeutic targets of CAD.