MicroRNA-221 is a potential biomarker of myocardial hypertrophy and fibrosis in hypertrophic obstructive cardiomyopathy

Comprehensive Transcriptomics Profiling of MicroRNA Reveals Plasma Circulating Biomarkers of Hypertrophic Cardiomyopathy and Dysregulated Signaling Pathways

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is caused by mutations in genes coding for proteins essential for myocardial contraction. However, it remains unclear through which signaling pathways these gene mutations mediate HCM pathogenesis. Growing evidence indicates that microRNAs (miRNAs) play an important role in the regulation of gene expression. We hypothesized that transcriptomics profiling of plasma miRNAs would reveal circulating biomarkers and dysregulated signaling pathways in HCM.

METHODS

We conducted a multicenter case-control study of cases with HCM and controls with hypertensive left ventricular hypertrophy. We performed plasma transcriptomics profiling of miRNAs using RNA sequencing. We developed a transcriptomics-based discrimination model using samples retrieved during the first two-thirds of the study period at one institution (training set). We prospectively tested its discriminative ability in samples collected thereafter from the same institution (prospective test set). We also externally validated the model by applying it to samples collected from the other institutions (external test set). We executed pathway analysis of dysregulated miRNAs with univariable P<0.05.

RESULTS

This study included 555 patients (392 cases and 163 controls). One thousand one hundred forty-one miRNAs passed our quality control filters. The area under the receiver operating characteristic curve of the transcriptomics-based model derived from the training set was 0.86 (95% CI, 0.79-0.93) in the prospective test set and 0.94 (95% CI, 0.90-0.97) in the external test set. Pathway analysis revealed dysregulation of the Ras-MAPK (mitogen-activated protein kinase) pathway and pathways related to inflammation in HCM.

CONCLUSIONS

This study utilized comprehensive transcriptomics profiling with RNA sequencing in HCM, revealing circulating miRNA biomarkers and dysregulated pathways.

The Overexpression of miR-377 Aggravates Sepsis-Induced Myocardial Hypertrophy by Binding to Rcan2 and Mediating CaN Activity

Sepsis remains a complicated and incompletely understood syndrome, and myocardial dysfunction is one of the main complications contributing to poor clinical outcomes. Accumulating evidence has revealed the critical involvement of the deregulated expression of specific microRNAs (miRNAs) in cardiac pathologies caused by sepsis. Intriguingly, miR-377 has been correlated with cardiomyocyte apoptosis, whereas its effect on myocardial hypertrophy remains to be illustrated. Thus, the current study sets out to explore the impact and underlying mechanism of miR-377 on myocardial hypertrophy induced by sepsis. The expression pattern of miR-377 was detected in myocardial tissues of septic mice induced by cecal ligation-perforation (CLP). We found that miR-377 was highly expressed in myocardial tissues of CLP-induced septic mice with cardiomyocyte hypertrophy. Besides, miR-377 inhibition could relieve cardiomyocyte hypertrophy and reduce inflammation in septic mice. Further, mechanistic studies found that miR-377 could target Rcan2 and then regulate calcineurin (CaN) activity via Ca2+/CaN signaling pathway. Collectively, our findings illuminate that miR-377 enhances myocardial hypertrophy caused by sepsis, by targeting Rcan2 and further regulating the Ca2+/CaN signaling pathway. This work highlights downregulation of miR-377 as a novel target for the management of sepsis-induced myocardial hypertrophy.

Differential Expression of microRNAs in Hypertrophied Myocardium and Their Relationship to Late Gadolinium Enhancement, Left Ventricular Hypertrophy and Remodeling in Hypertrophic Cardiomyopathy

Background: Differential expression has been found in a variety of circulating miRNAs in patients with hypertrophic cardiomyopathy (HCM). However, study on myocardial miRNAs is limited and a lot of miRNAs were not studied in previous studies. Methods: Twenty-one HCM patients and four patients who died from non-cardiovascular diseases were prospectively recruited for our study. A total of 26 myocardial tissues were collected, which were stored in liquid nitrogen immediately for miRNA detection using the Agilent Human miRNA Microarray Kit. All HCM patients underwent cardiovascular magnetic resonance (CMR) examination before surgery and cvi42 software was used to analyze cardiac function and myocardial fibrosis. Results: Compared with the control group, the expression of 22 miRNAs was found to be significantly increased in the HCM group, while 46 miRNAs were found to be significantly decreased in the HCM group. The expression levels of hsa-miR-3960 and hsa-miR-652-3p were significantly correlated with left ventricular mass index (r = 0.449 and 0.474, respectively). Meanwhile, Hsa-miR-642a-3p expression was positively correlated to the quantification of late gadolinium enhancement (r = 0.467). Conclusions: Our study found that 68 myocardial miRNAs were significantly increased or decreased in the HCM group. Myocardial miRNA levels could be used as potential biomarkers for LV hypertrophy, fibrosis and remodeling.

Correlation between decreased plasma miR-29a and vascular endothelial injury induced by hyperlipidemia

BACKGROUND

Hyperlipidemia is a major risk factor for vascular endothelial injury and atherosclerosis leading to cardiovascular diseases. Early diagnosis of vascular endothelial injury is important for the prevention and prognosis of cardiovascular diseases. This study aimed to investigate sensitive circulating microRNA (miRNA) as a potential diagnostic biomarker of vascular endothelial injury in a hyperlipidemic rat model.

METHODS

The miRNA expression profile was detected by miRNA microarray. The hyperlipidemic rat model was established by intraperitoneal injection of vitamin D₃ combined with a high-fat diet. Plasma miRNA levels were measured by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR).

RESULTS

No significant difference was found in the types of highly expressed miRNAs between human umbilical artery endothelial cells (HUAEC) and human umbilical vein endothelial cells (HUVEC). A total of 10 highly expressed miRNAs in endothelial cells were selected as candidate miRNAs, including miR-21, miR-126, let-7a, miR-23a, miR-221, miR-125b, miR-26a, miR-29a, miR-16, and miR-100. The plasma levels of let-7a, miR-126, miR-21, and miR-26a were significantly elevated in hyperlipidemic rats at 30 and 50 days after modeling, while the plasma level of miR-29a was significantly decreased. No significant change was found in the plasma levels of miR-125b, miR-23a, miR-221, miR-100, and miR-16. Interestingly, a significant reduction in plasma miR-29 level was detected as early as 20 days after modeling, which was earlier than for soluble intercellular adhesion molecule‑1 (sICAM-1).

CONCLUSION

The plasma levels of endothelial cell-enriched miRNAs were correlated with vascular endothelial injury induced by hyperlipidemia. miR-29a might serve as a potential early diagnostic biomarker of endothelial injury-related diseases.

MicroRNAs in Hypertrophic, Arrhythmogenic and Dilated Cardiomyopathy

MicroRNAs (miRNAs) are a class of non-coding RNAs of about 20 nucleotides in length, involved in the regulation of many biochemical pathways in the human body. The level of miRNAs in tissues and circulation can be deregulated because of altered pathophysiological mechanisms; thus, they can be employed as biomarkers for different pathological conditions, such as cardiac diseases. This review summarizes published findings of these molecular biomarkers in the three most common structural cardiomyopathies: human dilated, arrhythmogenic and hypertrophic cardiomyopathy.

Influence of miR-221/222 on cardiomyocyte calcium handling and function

Background

Cardiovascular disease is the leading cause of death worldwide. Cardiac electrical remodeling including altered ion channel expression and imbalance of calcium homeostasis can have detrimental effects on cardiac function. While it has been extensively reported that miR-221/222 are involved in structural remodeling, their role in electrical remodeling still has to be evaluated. We previously reported that subunits of the L-type Ca²⁺ channel (LTCC) are direct targets of miR-221/222. Furthermore, HL-1 cells transfected with miR-221 or -222 mimics showed a reduction in LTCC current density while the voltage-dependence of activation was not altered. The aim of the present study was to determine the influence of miR-221/222 on cardiomyocyte calcium handling and function.

Results

Transient transfection of HL-1 cells with miR-221/222 mimics led to slower depolarization-dependent Ca²⁺ entry and increased proportion of non-responding cells. Angiotensin II-induced Ca²⁺ release from the SR was not affected by miR-221/222. In miR-222-transfected neonatal cardiomyocytes the isoprenaline-induced positive inotropic effect on the intracellular Ca²⁺ transient was lost and the positive chronotropic effect on spontaneous beating activity was strongly reduced. This could have severe consequences for cardiomyocytes and could lead to a reduced contractility and systolic dysfunction of the whole heart.

Conclusions

This study adds a new role of miR-221/222 in cardiomyocytes by showing the impact on β-adrenergic regulation of LTCC function, calcium handling and beating frequency. Together with the previous report that miR-221/222 reduce GIRK1/4 function and LTCC current density, it expands our knowledge about the role of these miRs on cardiac ion channel regulation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00676-4.

Circulating microRNAs: Biomarkers of disease

MicroRNAs are a class of endogenous noncoding single-stranded RNA molecules with approximately 20-24 nucleotides and are associated with a broad range of biological processes. Researchers found that microRNAs are abundant in tissues, and more importantly, there are also trace circulating microRNAs that exist in biological fluids. In recent years, circulating microRNAs had emerged as promising diagnostic and prognostic biomarkers for the noninvasive detection of diseases with high specificity and sensitivity. More importantly, specific microRNA expression signatures reflect not only the existence of early-stage diseases but also the dynamic development of advanced-stage diseases, disease prognosis prediction, and drug resistance. To date, an increasing number of potential miRNA biomarkers have been reported, but their practical application prospects are still unclear. Therefore, microRNAs, as potential diagnostic and prognostic biomarkers in a variety of diseases, need to be updated, as they are of great importance in the diagnosis, prognosis and prediction of therapeutic responses. In this review, we summary our current understanding of microRNAs as potential biomarkers in the major diseases (e.g., cancers and cardio-cerebrovascular diseases), which provide the basis for the design of diagnosis and treatment plan and the improvement of the cure rate.

Blood-based protein profiling identifies serum protein c-KIT as a novel biomarker for hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is one of the most common hereditary heart diseases and can be classified into an obstructive (HOCM) and non-obstructive (HNCM) form. Major characteristics for HCM are the hypertrophy of cardiomyocytes and development of cardiac fibrosis. Patients with HCM have a higher risk for sudden cardiac death compared to a healthy population. In the present study, we investigated the abundancy of selected proteins as potential biomarkers in patients with HCM. We included 60 patients with HCM and 28 healthy controls and quantitatively measured the rate of a set of 92 proteins already known to be associated with cardiometabolic processes via protein screening using the proximity extension assay technology in a subgroup of these patients (20 HCM and 10 healthy controls). After validation of four hits in the whole cohort of patients consisting of 88 individuals (60 HCM patients, 28 healthy controls) we found only one candidate, c-KIT, which was regulated significantly different between HCM patients and healthy controls and thus was chosen for further analyses. c-KIT is a tyrosine-protein kinase acting as receptor for the stem cell factor and activating several pathways essential for cell proliferation and survival, hematopoiesis, gametogenesis and melanogenesis. Serum protein levels of c-KIT were significantly lower in patients with HCM than in healthy controls, even after adjusting for confounding factors age and sex. In addition, c-KIT levels in human cardiac tissue of patients with HOCM were significant higher compared to controls indicating high levels of c-KIT in fibrotic myocardium. Furthermore, c-KIT concentration in serum significantly correlated with left ventricular end-diastolic diameter in HOCM, but not HCM patients. The present data suggest c-KIT as a novel biomarker differentiating between patients with HCM and healthy population and might provide further functional insights into fibrosis-related processes of HOCM.

Cardiomyopathies in China: A 2018-2019 state-of-the-art review

Cardiomyopathies are diseases of the cardiac muscle and are often characterized by ventricular dilation, hypertrophy, and cardiac arrhythmia. Patients with cardiomyopathies often experience sudden death and cardiac failure and require cardiac transplantation during the course of disease progression. Early diagnosis, differential diagnosis, and genetic consultation depend on imaging techniques, genetic testing, and new emerging diagnostic tools such as serum biomarkers. The molecular genetics of cardiomyopathies has been widely studied recently. The discovery of mechanisms underlying heterogeneity and overlapping of the phenotypes of cardiomyopathies has revealed the existence of disease modifiers, and this has led to the emergence of novel disease-modifying therapy. This 2018-2019 state-of-the-art review outlines the pathogenesis, diagnosis, and treatment of cardiomyopathies in China.

A systematic review of microRNAs in patients with hypertrophic cardiomyopathy

BACKGROUND

Several microRNAs (miRNA) have been associated with hypertrophic cardiomyopathy (HCM), but studies differ regarding methods employed. In an attempt to understand their role in the disease, we performed a systematic review of studies assessing miRNAs and their association with HCM.

METHODS

The literature search was based on The Medical Subject Headings (MeSH) terms "Hypertrophic Cardiomyopathy" and "MicroRNA" combined with other synonyms on Embase, Medline and LILACS databases in April 2020. The selected studies and data extraction were independently evaluated. Only human reports with a clear definition of HCM diagnosis were included.

RESULTS

The search found 68 studies, 13 fulfilled the selection criteria, with a total of 329 patients. Eighty-seven miRNA were differentially expressed in HCM patients, being mir-21, mir-29a and mir-133 the most reported. The miRNA were mainly up-regulated, where mir-29a was up-regulated in 6 studies, followed by mir-133 in 4 and mir-21 in 3. The other miRNAs were mainly up-regulated. Blood samples were evaluated in the majority of patients (86%), but a greater number of miRNAs (79%) were assessed in myocardium. Six studies evaluating the phenotype correlation demonstrated that several miRNAs, mainly mir-1-3p, mir-19b, mir-21, mir-29a, mir-155, and mir-221, were related to either hypertrophy or fibrosis. Mir-29a showed a more consistent phenotypic correlation.

CONCLUSION

Eighty-seven miRNAs were differentially expressed in HCM patients, the majority in up-regulation. Mir-21, mir-29a and mir-133 were the most reported. Correlation with left ventricular hypertrophy and fibrosis was evaluated in six studies for several miRNAs, nevertheless, mir-29a showed more consistent findings and seems to be a promising biomarker.

Circulating mRNA and microRNA profiling analysis in patients with ischemic stroke

To provide insight into molecular diagnosis and individualized treatment of ischemic stroke (IS), several available datasets in IS were analyzed to identify the differentially expressed genes and microRNAs (miRNAs). Series matrix files from GSE22255 and GSE16561 (mRNA profiles), a well as GSE110993 (miRNA profile) were downloaded from the Gene Expression Omnibus database. System-level clustering was performed with GeneCluster 3.0 software, and gene annotation and pathway enrichment were performed with gene ontology analysis and Database for Annotation, Visualization and Integrated Discovery software. For a protein-protein interaction (PPI) network, Biological General Repository for Interaction Datasets and IntAct interaction information were integrated to determine the interaction of differentially expressed genes. The selected miRNA candidates were imported into the TargetScan, miRDB and miRecords databases for the prediction of target genes. The present study identified 128 upregulated and 231 downregulated genes in female stroke patients, and 604 upregulated and 337 downregulated genes in male stroke patients compared with sex- and age-matched controls. The construction of a PPI network demonstrated that male stroke patients exhibited YWHAE, CUL3 and JUN as network center nodes, and in female patients CYLD, FOS and PIK3R1 interactions were the strongest. Notably, these interactions are mainly involved in immune inflammatory response, apoptosis and other biological pathways, such as blood coagulation. Female and male upregulated genes were cross-validated with another set of Illumina HumanRef-8 v3.0 expression beadchip (GSE16561). Functional item association networks, gene function networks and transcriptional regulatory networks were successfully constructed, and the relationships between miRNAs and target genes were successfully predicted. The present study identified a number of transcription factors, including DEFA1, PDK4, SDPR, TCN1 and MMP9, and miRNAs, including miRNA (miR)-21, miR-143/145, miR-125-5p and miR-122, which may serve important roles in the development of cerebral stroke and may be important molecular indicators for the treatment of IS.

Down-Regulated Exosomal MicroRNA-221 - 3p Derived From Senescent Mesenchymal Stem Cells Impairs Heart Repair

The composition and biological activity of donor cells is largely determined by the exosomes they secrete. In this study, we isolated exosomes from young (Young-Exo) and aged (Age-Exo) mesenchymal stem cells (MSCs) and compared their regeneration activity. Young Exo MSCs were more efficient than Aged-Exo at promoting the formation of endothelial tube, reducing fibrosis, and inhibiting apoptosis of cardiomyocytes in vitro; and improving cardiac structure and function in vivo in the hearts of rats following myocardial infarction (MI). MicroRNA sequencing and polymerase chain reaction (PCR) analysis revealed that miR-221-3p was significantly down-regulated in Aged-Exo. The aged MSCs were rejuvenated and their reparative cardiac ability restored when miR-221-3p was overexpressed in Aged-Exo. The protective effect was lost when miR-221-3p expression was knocked down in Young-Exo. These effects of miR-221-3p were achieved through enhancing Akt kinase activity by inhibiting phosphatase and tensin homolog (PTEN). In conclusion, exosomal miR-221-3p secreted from Aged MSCs attenuated the function of angiogenesis and promoted survival of cardiomyocytes. Up-regulation of miR-221-3p in aged MSCs improved their ability of angiogenesis, migration and proliferation, and suppressed apoptosis via the PTEN/Akt pathway.