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Emanueli, C.

Publications and source records attributed to Emanueli, C..

4 recordsLinked to original sources

circRNA-miRNA-mRNA networks reveal a proangiogenic action of circNPHP1 in human ischemic heart disease

BackgroundIschemic heart disease (IHD) is characterized by insufficient myocardial blood flow in the left ventricle and aggravated by diabetes mellitus. Endothelial resilience and reparative angiogenesis are tightly controlled processes. Gene expression is regulated by multimodal interactions between RNA species. Circular RNAs (circRNAs) can sponge microRNAs (miRNAs) to reduce the repressive effects of miRNAs on its messenger RNA (mRNAs) targets. MethodsLeft ventricle whole RNA-sequencing (circRNAs, mRNAs) and small RNA- sequencing (miRNAs) datasets were obtained from 3 patient groups: IHD with/out T2DM and controls (N=11 to 12/group) as part of a prospective observational cardiac surgery study. The interactions between differentially expressed (DE) circRNAs, miRNA and mRNAs were identified with a customized bioinformatics pipeline. The emerging networks were screened using endothelial-specific RNA-sequencing datasets from GEO resulting in EC-rich networks. CircRNAs from these networks were subsequently screened (RT-PCR) in endothelial cells (ECs) exposed to disease-mimicking conditions vs control. Afterwards, circRNA pulldown allowed to interrogate the circRNA-miRNAs interactome in ECs. EC biology assays using loss-of-function and gain-of-function approaches corroborated the study. ResultsWe identified novel circRNA-miRNA-mRNA interactions in the human diseased heart. CircNPHP1, which is upregulated in IHD with/out Type-2 diabetes mellitus (T2DM), sponges miR-221-3p to de-repress VEGF-A and BCL2, increasing the angiogenic capacity of ECs under disease and disease-mimicking conditions. ConclusionsThe interactions between individual members of different RNA species are affected by IHD. The therapeutic value of circNPHP1/miR-221-3p axis could be further investigated. Visual Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=61 SRC="FIGDIR/small/597402v2_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@18a3b0forg.highwire.dtl.DTLVardef@2b5dc1org.highwire.dtl.DTLVardef@11848c3org.highwire.dtl.DTLVardef@1511c9e_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIWe found a novel circRNA-miRNA-mRNA network in IHD and Type 2 diabetes. C_LIO_LICircNPHP1 regulates angiogenesis and proliferation in the cardiac ECs exposed to conditions mimicking IHD and Type 2 diabetes. C_LIO_LIWe elucidated a novel pro-angiogenic subnetwork commanded by circNPHP1/miR-221-3p/BCL2/VEGFA. C_LIO_LIWe identified circNPHP1 as a potential new target for therapeutic angiogenesis. C_LI

cell biology↗

Interleukin 11-induced microRNAs as functional mediators and circulating biomarkers of cardiac fibrosis

BackgroundCardiac fibrosis can be triggered by several pathologies, including ischemic heart disease and aortic stenosis (AS). Cardiac fibrosis is brought about by uncontrolled extracellular matrix (ECM) deposition by myofibroblasts. Interleukin-11 (IL-11) has been firmly demonstrated to be a major trigger of multi-organ fibrosis. However, the molecular mechanisms underpinning IL-11-induced fibrosis requires further characterisation. Recent studies indicate that microRNA (miRNA) dysregulation contributes to the pathogenesis of cardiac fibrosis and can be targeted therapeutically. In this study, we explored the hypothesis that miRNAs act as downstream effectors of IL-11-induced cardiac fibrosis. Moreover, we investigated the translational potential of IL-11-regulated miRNAs as circulating biomarkers of cardiac fibrosis in AS patients. Methods and ResultsUsing computational approaches, we identified miRNA-497-5p and miRNA-27b-5p as potential new downstream profibrotic effectors of IL-11 in fibroblasts. We next confirmed that both miRNAs increased in healthy rat CF stimulated with IL-11 and in CF derived from post-infarction failing hearts. At the functional level, miRNA-497-5p and miRNA-27b-5p inhibition indirectly reduced the mRNA expression of collagen 1 (Col1a1). Conversely, transfection of CFs with mimics for each of the two miRNAs promoted fibroblast-to-myofibroblast transition and increased Col1a1 levels. We provided evidences that miRNA-27b-5p and miRNA-497-5p converge to promote hypoxia-inducible factor 1 signalling, by targeting its regulator EGLN (PHD) family members. The clinical relevance of our findings was confirmed using left ventricle (LV) specimens obtained from surgical patients with AS. The miRNA-27b-5p and miRNA-497-5p measured in the LV, peripheral plasma and plasma extracellular vesicles correlated with the severity of LV fibrosis, indicating these miRNAs potential as new circulating biomarkers of cardiac fibrosis. ConclusionsIn this study, we have newly identified the potential value of miRNA-27b-5p and miRNA-497-5p as actionable biomarkers of the profibrotic response to IL-11 in the heart. Future studies should validate the translational potential of the miRNAs as new clinical biomarkers and therapeutic targets.

molecular biology↗

Multi-response Mendelian randomization: Identification of shared and distinct exposures for multimorbidity and multiple related disease outcomes

The existing framework of Mendelian randomization (MR) infers the causal effect of one or multiple exposures on one single outcome. It is not designed to jointly model multiple outcomes, as would be necessary to detect causes of more than one outcome and would be relevant to model multimorbidity or other related disease outcomes. Here, we introduce Multi-response Mendelian randomization (MR2), a novel MR method specifically designed for multiple outcomes to identify exposures that cause more than one outcome or, conversely, exposures that exert their effect on distinct responses. MR2 uses a sparse Bayesian Gaussian copula regression framework to detect causal effects while estimating the residual correlation between summary-level outcomes, i.e., the correlation that cannot be explained by the exposures, and viceversa. We show both theoretically and in a comprehensive simulation study how unmeasured shared pleiotropy induces residual correlation. We also reveal how non-genetic factors that affect more than one outcome contribute to their correlation. We demonstrate that by accounting for residual correlation, MR2 has higher power to detect shared exposures causing more than one outcome. It also provides more accurate causal effect estimates than existing methods that ignore the dependence between related responses. Finally, we illustrate how MR2 detects shared and distinct causal exposures for five cardiovascular diseases in two applications considering cardiometabolic and lipidomic exposures and uncovers residual correlation between summary-level outcomes reflecting known relationships between cardiovascular diseases.

genetics↗

In vivo characterisation of endogenous cardiovascular extracellular vesicles in larval and adult zebrafish

ObjectiveExtracellular vesicles (EVs) facilitate molecular transport across extracellular space, allowing local and systemic signalling during homeostasis and in disease. Extensive studies have described functional roles for EV populations, including during cardiovascular disease, but the in vivo characterisation of endogenously produced EVs is still in its infancy. Due to their genetic tractability and opportunities for live imaging, zebrafish represent an ideal but under-used model to investigate endogenous EVs. The overall aim of this study was to establish a transgenic zebrafish model to allow the in vivo identification, tracking and extraction of endogenous EVs produced by different cell types. Approach and ResultsUsing a membrane-tethered fluorophore reporter system, we show that EVs can be fluorescently labelled in larval and adult zebrafish and demonstrate that multiple cell types including endothelial cells and cardiomyocytes actively produce EVs in vivo. Cell-type specific EVs can be tracked by high spatiotemporal resolution light-sheet live imaging and modified flow cytometry methods allow these EVs to be further evaluated. Importantly, we demonstrate the utility of this model by showing that cardiomyocytes, endothelial cells and macrophages exchange EVs in the adult heart and that ischaemic injury models dynamically alter EV production. ConclusionsWe have developed a powerful in vivo zebrafish model for the investigation of endogenous EVs in all aspects of cardiovascular biology and pathology. A cell membrane fluorophore labelling approach allows cell type-specific tracing of EV origin without bias towards the expression of individual protein markers and will allow detailed future examination of their function.

cell biology↗