miRNA-197 and miRNA-223 and cardiovascular death in coronary artery disease patients

Novel Anti Double-Stranded Nucleic Acids Full-Length Recombinant Camelid Heavy-Chain Antibody for the Detection of miRNA

The discovery that certain diseases have specific miRNA signatures which correspond to disease progression opens a new biomarker category. The detection of these small non-coding RNAs is performed routinely using body fluids or tissues with real-time PCR, next-generation sequencing, or amplification-based miRNA assays. Antibody-based detection systems allow an easy onset handling compared to PCR or sequencing and can be considered as alternative methods to support miRNA diagnostic in the future. In this study, we describe the generation of a camelid heavy-chain-only antibody specifically recognizing miRNAs to establish an antibody-based detection method. The generation of nucleic acid-specific binders is a challenge. We selected camelid binders via phage display, expressed them as VHH as well as full-length antibodies, and characterized the binding to several miRNAs from a signature specific for dilated cardiomyopathy. The described workflow can be used to create miRNA-specific binders and establish antibody-based detection methods to provide an additional way to analyze disease-specific miRNA signatures.

MicroRNA-197-3p mediates damage to human coronary artery endothelial cells via targeting TIMP3 in Kawasaki disease

Kawasaki disease (KD) causes cardiovascular system injury in children. However, the pathogenic mechanisms of KD have not been well defined. Recently, strong correlation between aberrant microRNAs and KD nosogenesis has been revealed. A role of microRNA-197-3p (miR-197-3p) in the pathogenesis of KD is identified in the present study. Cell proliferation assay showed human coronary artery endothelial cells (HCAECs) were suppressed by serum from KD patients, which was correlated with high levels of miR-197-3p in both KD serum and HCAECs cultured with KD serum. The inhibition of HCAECs by miR-197-3p was confirmed by cells expressing miR-197-3p mimic and miR-197-3p inhibitor. Comparative proteomics analysis and Ingenuity Pathway Analysis (IPA) revealed TIMP3 as a potential target of miR-197-3p, which was demonstrated by western blot and dual-luciferase reporter assays. Subsequently, by detecting the endothelium damage markers THBS1, VWF, and HSPG2, the role of miR-197-3p/TIMP3 in KD-induced damage to HCAECs was confirmed, which was further validated by a KD mouse model in vivo. The expressions of miR-197-3p and its target, TIMP3, are dramatically variational in KD serum and HCAECs cultured with KD serum. Increased miR-197-3p induces HCAECs abnormal by restraining TIMP3 expression directly. Hence, dysregulation of miR-197-3p/TIMP3 expression in HCAECs may be an important mechanism in cardiovascular endothelium injury in KD patients, which offers a feasible therapeutic target for KD treatment.

MicroRNA profiling as a novel diagnostic tool for identification of patients with inflammatory and/or virally induced cardiomyopathies

AIMS

MicroRNAs (miRNAs) might be used as prospective biomarkers for the identification of unexplained heart failure caused by a viral and/or inflammatory process. The aim of this study was to identify and to evaluate prognostic miRNAs in serum of patients with inflammatory heart diseases diagnosed by endomyocardial biopsies.

METHODS AND RESULTS

After TaqMan® OpenArray® screening of 754 unique circulating miRNAs in serum of biopsy-proven patients [184 patients with inflammatory and/or virally induced myocardial diseases (DCMi), 25 patients with dilated cardiomyopathy (DCM), and 25 healthy donors], we identified seven miRNAs of interest (P < 0.05). These data have been verified by single qRT-PCR assays in other biopsy-proven patients (159 patients with viral and/or inflammatory myocardial diseases, 46 patients with DCM, and 60 healthy donors). The expression of let-7f, miR-197, miR-223, miR-93, and miR-379 allowed us to differentiate between patients with a virus and/or inflammation and healthy donors (P < 0.05) with the specificity over 93%. Based on the expression of miR-21 and miR-30a-5p, we could sort out patients with DCM from all other study groups (P < 0.05) with the specificity over 95%.

CONCLUSIONS

This miRNA profile provides for the first time a new non-invasive diagnostic perspective to identify patients with intramyocardial inflammation and/or viral persistence only from single serum sample, independently of prescribed therapy and time of symptoms onset. It allows the early finding of those patients relevant for myocardial biopsy for exact diagnosis and further proscription of causal aetiology-driven specific treatment.

MicroRNAs or Long Noncoding RNAs in Diagnosis and Prognosis of Coronary Artery Disease

Coronary artery disease (CAD) is the result of atherosclerotic plaque development in the wall of the coronary arteries. The underlying mechanism involves atherosclerosis of the arteries of the heart which is a relatively complex process comprising several steps. In CAD, atherosclerosis induces functional and structural changes. The pathogenesis of CAD results from various changes in and interactions between multiple cell types in the artery walls; these changes mainly include endothelial cell (EC) dysfunction, vascular smooth muscle cell (SMC) alteration, lipid deposition and macrophage activation. Various blood markers associated with an increased risk for cardiovascular endpoints have been identified; however, few have yet been shown to have a diagnostic impact or important clinical implications that would affect patient management. Noncoding RNAs, especially microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), can be stable in plasma and other body fluids and could therefore serve as biomarkers for some diseases. Many studies have shown that some miRNAs and lncRNAs play key roles in heart and vascular development and in cardiac pathophysiology. Thus, we summarize here the latest research progress, focusing on the molecular mechanism of miRNAs and lncRNAs in CAD, with the intent of seeking new targets for the treatment of heart disease.

miR-3646 promotes vascular inflammation and augments vascular smooth muscle cell proliferation and migration in progression of coronary artery disease by directly targeting RHOH

Coronary artery disease (CAD) is one of the leading causes of mortality and morbidity worldwide and the number of individuals at CAD risk is increasing. To better manage cardiovascular disease, improved tools for risk prediction including the identification of novel accurate biomarkers are needed. MicroRNAs (miRNAs) are small non-coding RNAs that modulate the expression of protein-coding genes at the post-transcription level and their dysregulated expression has been implicated in various pathogenic processes including cardiovascular disease. Circulating miRNAs have been widely recommended as potential biomarkers for many diseases including coronary artery disease. In the present study, we found that miR-3646 was significantly upregulated in the serum samples of CAD patients and in the mice with acute myocardial infarction (AMI) compared with the healthy control group via using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Moreover, the serum levels of miR-3646 were significantly positively correlated with the expression of IL-6 both in CAD patient samples and AMI mice samples. In human THP-1 macrophages, transfection with miR-3646 mimic elevated the expression of IL-6 while silence of miR-3646 suppressed the IL-6 level. Further exploration of the downstream targets of miR-3646 identified that blocking RHOH expression also could upregulate IL-6 expression. In addition, our findings also showed that miR-3646 promoted vascular smooth muscle cell (VSMC) proliferation and migration by targeting RHOH. These results demonstrate that the miR-3646-RHOH axis may serve as a key regulator in the progression of CAD by modulating vascular inflammation and regulating the biologic behaviors of VSMCs.