miR-421 and miR-30c inhibit SERPINE 1 gene expression in human endothelial cells

Moyamoya disease-specific extracellular vesicle-derived microRNAs in the cerebrospinal fluid revealed by comprehensive expression analysis through microRNA sequencing

PURPOSE

To examine the specific changes that occur in the expression levels of extracellular vesicle-derived microRNAs (miRNAs) in intracranial cerebrospinal fluid (CSF) in moyamoya disease.

METHODS

Patients with arteriosclerotic cerebral ischemia were used as controls to eliminate the effects of cerebral ischemia. Intracranial CSF was collected from moyamoya disease and control patients during bypass surgery. Extracellular vesicles (EVs) were extracted from the CSF. Comprehensive expression analysis of miRNAs extracted from EVs by next-generation sequencing (NGS) and validation by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed.

RESULTS

Experiments were conducted on eight cases of moyamoya disease and four control cases. In the comprehensive miRNA expression analysis, 153 miRNAs were upregulated, and 98 miRNAs were downregulated in moyamoya disease compared to the control cases (q-value < 0.05 and |log2 fold change|> 1). qRT-PCR performed on the four most variable miRNAs (hsa-miR-421, hsa-miR-361-5p, hsa-miR-320a, and hsa-miR-29b-3p) associated with vascular lesions among the differentially expressed miRNAs gave the same results as miRNA sequencing. On gene ontology (GO) analysis for the target genes, cytoplasmic stress granule was the most significant GO term.

CONCLUSIONS

This study is the first comprehensive expression analysis of EV-derived miRNAs in the CSF of moyamoya disease patients using NGS. The miRNAs identified here may be related to the etiology and pathophysiology of moyamoya disease.

Post-transcriptional control of haemostatic genes: mechanisms and emerging therapeutic concepts in thrombo-inflammatory disorders

The haemostatic system is pivotal to maintaining vascular integrity. Multiple components involved in blood coagulation have central functions in inflammation and immunity. A derailed haemostasis is common in prevalent pathologies such as sepsis, cardiovascular disorders, and lately, COVID-19. Physiological mechanisms limit the deleterious consequences of a hyperactivated haemostatic system through adaptive changes in gene expression. While this is mainly regulated at the level of transcription, co- and posttranscriptional mechanisms are increasingly perceived as central hubs governing multiple facets of the haemostatic system. This layer of regulation modulates the biogenesis of haemostatic components, for example in situations of increased turnover and demand. However, they can also be 'hijacked' in disease processes, thereby perpetuating and even causally entertaining associated pathologies. This review summarizes examples and emerging concepts that illustrate the importance of posttranscriptional mechanisms in haemostatic control and crosstalk with the immune system. It also discusses how such regulatory principles can be used to usher in new therapeutic concepts to combat global medical threats such as sepsis or cardiovascular disorders.

Association between PAI-1 Polymorphisms and Ischemic Stroke in a South Korean Case-Control Cohort

Stroke is the second leading cause of death in the world. Approximately 80% of strokes are ischemic in origin. Many risk factors have been linked to stroke, including an increased level of plasminogen activator inhibitor-1 (PAI-1). PAI-1 levels increase and remain elevated in blood during the acute phase of ischemic stroke, which can impair fibrinolytic activity, leading to coronary artery disease and arterial thrombotic disorders. Here, we present a case-control study of 574 stroke patients and 425 controls seen for routine health examination or treatment for nonspecific dizziness, nonorganic headache, or anxiety for positive family history of stroke at the Bundang Medical Center in South Korea. Polymorphisms in PAI-1 were identified by polymerase chain reaction/restriction fragment length polymorphism analysis using genomic DNA. Specifically, three variations (-675 4G>5G, 10692T>C, and 12068G>A) were linked to a higher overall prevalence of stroke as well as a higher prevalence of certain stroke subtypes. Haplotype analyses also revealed combinations of these variations (-844G>A, -675 4G>5G, 43G>A, 9785A>G, 10692T>C, 11053T>G, and 12068G>A) that were significantly associated with a higher prevalence of ischemic stroke. To the best of our knowledge, this is the first strong evidence that polymorphic sites in PAI-1 promoter and 3'-UTR regions are associated with higher ischemic stroke risk. Furthermore, the PAI-1 genotypes and haplotypes identified here have potential as clinical biomarkers of ischemic stroke and could improve the prognosis and future management of stroke patients.

Association of SNPs in the PAI1 Gene with Disease Recurrence and Clinical Outcome in Bladder Cancer

PURPOSE

Bladder cancer (BCa) is one of the most common cancer types worldwide and is characterized by a high rate of recurrence. In previous studies, we and others have described the functional influence of plasminogen activator inhibitor-1 (PAI1) in bladder cancer development. While polymorphisms in PAI1 have been associated with increased risk and worsened prognosis in some cancers, the mutational status of PAI1 in human bladder tumors has not been well defined.

METHODS

In this study, we evaluated the mutational status of PAI1 in a series of independent cohorts, comprised of a total of 660 subjects.

RESULTS

Sequencing analyses identified two clinically relevant 3' untranslated region (UTR) single nucleotide polymorphisms (SNPs) in PAI1 (rs7242; rs1050813). Somatic SNP rs7242 was present in human BCa cohorts (overall incidence of 72%; 62% in Caucasians and 72% in Asians). In contrast, the overall incidence of germline SNP rs1050813 was 18% (39% in Caucasians and 6% in Asians). Furthermore, Caucasian patients with at least one of the described SNPs had worse recurrence-free survival and overall survival (p = 0.03 and p = 0.03, respectively). In vitro functional studies demonstrated that SNP rs7242 increased the anti-apoptotic effect of PAI1, and SNP rs1050813 was related to a loss of contact inhibition associated with cellular proliferation when compared to wild type.

CONCLUSION

Further investigation of the prevalence and potential downstream influence of these SNPs in bladder cancer is warranted.

Inducible miR-1224 silences cerebrovascular Serpine1 and restores blood flow to the stroke-affected site of the brain

The α-tocotrienol (TCT) form of natural vitamin E is more potent than the better known α-tocopherol against stroke. Angiographic studies of canine stroke have revealed beneficial cerebrovascular effects of TCT. This work seeks to understand the molecular basis of such effect. In mice, TCT supplementation improved perfusion at the stroke-affected site by inducing miR-1224. miRNA profiling of a laser-capture-microdissected stroke-affected brain site identified miR-1224 as the only vascular miR induced. Lentiviral knockdown of miR-1224 significantly blunted the otherwise beneficial effects of TCT on stroke outcomes. Studies on primary brain microvascular endothelial cells revealed direct angiogenic properties of miR-1224. In mice not treated with TCT, advance stereotaxic delivery of an miR-1224 mimic to the stroke site markedly improved stroke outcomes. Mechanistic studies identified Serpine1 as a target of miR-1224. Downregulation of Serpine1 augmented the angiogenic response of the miR-1224 mimic in the brain endothelial cells. The inhibition of Serpine1, by dietary TCT and pharmacologically, increased cerebrovascular blood flow at the stroke-affected site and protected against stroke. This work assigns Serpine1, otherwise known to be of critical significance in stroke, a cerebrovascular function that worsens stroke outcomes. miR-1224-dependent inhibition of Serpine1 can be achieved by dietary TCT as well as by the small-molecule inhibitor TM5441.

Emerging Role of MicroRNA-30c in Neurological Disorders

MicroRNAs (miRNAs or miRs) are a class of small non-coding RNAs that negatively regulate the expression of target genes by interacting with 3' untranslated regions of target mRNAs to induce mRNA degradation and translational repression. The miR-30 family members are involved in the development of many tissues and organs and participate in the pathogenesis of human diseases. As a key member of the miR-30 family, miR-30c has been implicated in neurological disorders such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke. Mechanistically, miR-30c may act as a multi-functional regulator of different pathogenic processes such as autophagy, apoptosis, endoplasmic reticulum stress, inflammation, oxidative stress, thrombosis, and neurovascular function, thereby contributing to different disease states. Here, we review and discuss the biogenesis, gene regulation, and the role and mechanisms of action of miR-30c in several neurological disorders and therapeutic potential in clinics.

TMAO Upregulates Members of the miR-17/92 Cluster and Impacts Targets Associated with Atherosclerosis

Atherosclerosis is a hallmark of cardiovascular disease, and lifestyle strongly impacts its onset and progression. Nutrients have been shown to regulate the miR-17/92 cluster, with a role in endothelial function and atherosclerosis. Choline, betaine, and L-carnitine, found in animal foods, are metabolized into trimethylamine (TMA) by the gut microbiota. TMA is then oxidized to TMAO, which has been associated with atherosclerosis. Our aim was to investigate whether TMAO modulates the expression of the miR-17/92 cluster, along with the impact of this modulation on the expression of target genes related to atherosclerosis and inflammation. We treated HepG-2 cells, THP-1 cells, murine liver organoids, and human peripheral mononuclear cells with 6 µM of TMAO at different timepoints. TMAO increased the expression of all analyzed members of the cluster, except for miR-20a-5p in murine liver organoids and primary human macrophages. Genes and protein levels of SERPINE1 and IL-12A increased. Both have been associated with atherosclerosis and cardiovascular disease (CDVD) and are indirectly modulated by the miR-17-92 cluster. We concluded that TMAO modulates the expression of the miR-17/92 cluster and that such modulation could promote inflammation through IL-12A and blood clotting through SERPINE1 expression, which could ultimately promote atherosclerosis and CVD.

Serpine1 Regulates Peripheral Neutrophil Recruitment and Acts as Potential Target in Ischemic Stroke

Introduction

Peripheral neutrophil infiltration can exacerbate ischemia–reperfusion injury. We focused on the relationship between various peripheral immune cells and cerebral ischemia–reperfusion (I/R) injury.

Methods

In this study, we investigated the effects of dauricine on neuronal injury induced by ischemia–reperfusion and peripheral immune cells after ischemic stroke in mouse model, and we explored the undefined mechanisms of regulating peripheral immune cells through RNA sequencing and various biochemical verification in vitro and in vivo.

Results

We found that dauricine improved the neurological deficits of I/R injury, reduced the infarct volume, and improved the neurological scores. Furthermore, dauricine reduced the infiltration of neutrophils into the brain after MCAO-R and increased peripheral neutrophils but unchanged the permeability of the endotheliocyte Transwell system in an in vitro blood-brain barrier (BBB) model. RNA sequencing showed that chemotaxis factors, such as CXCL3, CXCL11, CCL20, CCL22, IL12a, IL23a, and serpine1, might play a crucial role. Overexpression of serpine1 reversed LPS-induced migration of neutrophils. Dauricine can directly bind with serpine1 in ligand–receptor docking performed with the Autodock and analyzed with PyMOL.

Conclusion

We identified chemotaxis factor serpine1 played a crucial role in peripheral neutrophil infiltration, which may contribute to reduce the neuronal injury induced by ischemia–reperfusion. These findings reveal that serpine1 may act as a potential treatment target in the acute stage of ischemic stroke.

Impacts of circulating microRNAs in exercise-induced vascular remodeling

Cardiovascular adaptation underlies all athletic training modalities, with a variety of factors contributing to overall response during exercise-induced stimulation. In this regard the role of circulating biomarkers is a well-established and invaluable tool for monitoring cardiovascular function. Specifically, novel biomarkers such as circulating cell free DNA and RNA are now becoming attractive tools for monitoring cardiovascular function with the advent of next generation technologies that can provide unprecedented precision and resolution of these molecular signatures, paving the way for novel diagnostic and prognostic avenues to better understand physiological remodeling that occurs in trained versus untrained states. In particular, microRNAs are a species of regulatory RNAs with pleiotropic effects on multiple pathways in tissue-specific manners. Furthermore, the identification of cell free microRNAs within peripheral circulation represents a distal signaling mechanism that is just beginning to be explored via a diversity of molecular and bioinformatic approaches. This article provides an overview of the emerging field of sports/performance genomics with a focus on the role of microRNAs as novel functional diagnostic and prognostic tools, and discusses present knowledge in the context of athletic vascular remodeling. This review concludes with current advantages and limitations, touching upon future directions and implications for applying contemporary systems biology knowledge of exercise-induced physiology to better understand how disruption can lead to pathology.

The Role of Epigenetics in the Regulation of Hemostatic Balance

Epigenetics, a term conventionally used to explain the intricate interplay between genes and the environment, is now regarded as the fundament of developmental biology. Several lines of evidence garnered over the past decades suggest that epigenetic alterations, mostly encompassing DNA methylation, histone tail modifications, and generation of microRNAs, play an important, though still incompletely explored, role in both primary and secondary hemostasis. Epigenetic variations may interplay with platelet functions and their responsiveness to antiplatelet drugs, and they may also exert a substantial contribution in modulating the production and release into the bloodstream of proteins involved in blood coagulation and fibrinolysis. This emerging evidence may have substantial biological and clinical implications. An enhanced understanding of posttranscriptional mechanisms would help to clarify some remaining enigmatic issues in primary and secondary hemostasis, which cannot be thoughtfully explained by genetics or biochemistry alone. Increased understanding would also pave the way to developing innovative tests for better assessment of individual risk of bleeding or thrombosis. The accurate recognition of key epigenetic mechanisms in hemostasis would then contribute to identify new putative therapeutic targets, and develop innovative agents that could be helpful for preventing or managing a vast array of hemostasis disturbances.

Plasminogen activator inhibitor-1: a potential etiological role in livedoid vasculopathy

Livedoid vasculopathy (LV) is a chronic, recurrent skin disorder with unknown aetiology and pathogenesis that seriously affects the quality of life of people who suffer from it. Plasminogen activator inhibitor (PAI)-1 is a primary inhibitory component of the endogenous fibrinolytic system in blood coagulation. PAI-1 also plays a role in many other physiological processes and activities, including thrombosis, fibrosis, wound healing, angiogenesis, inflammation, cell migration, and adhesion. Enhanced expression and genotype polymorphism of PAI-1 have been observed in LV patients. In this review, we summarise the known functions of PAI-1 with emphasis on the roles that PAI-1 probably plays in the pathogenesis of LV, thereby illustrating that PAI-1 represents a potential LV biomarker and therapeutic target for treating LV.

A narrative review of antithrombin use during veno-venous extracorporeal membrane oxygenation in adults: rationale, current use, effects on anticoagulation, and outcomes

BACKGROUND

During extracorporeal membrane oxygenation, the large contact surface between the blood and the extracorporeal circuit causes a continuous activation of coagulation and inflammation. Unfractionated heparin, a glycosaminoglycan that must bind to antithrombin as a cofactor, is currently the standard anticoagulant adopted during extracorporeal membrane oxygenation. Antithrombin, beyond being a potent natural anticoagulant, acts in the cross-talk between coagulation and inflammatory system through anticoagulation and coagulation-independent effects.

OBJECTIVES

In this review, we describe, in the adult setting of veno-venous extracorporeal membrane oxygenation, the pathophysiological rationale for antithrombin use, the current practice of administration, and the effects of antithrombin on anticoagulation, bleeding, and outcomes.

DATA SOURCES

Studies on adults (18 years or older) on veno-venous extracorporeal membrane oxygenation published from 1995 to 2018 in order to evaluate the use of antithrombin.

RESULTS

In adults on veno-venous extracorporeal membrane oxygenation, antithrombin supplementation has a highly pathophysiological rationale since coagulation factor consumption, systemic inflammatory response syndrome, and endothelial activation are triggered by extracorporeal membrane oxygenation. Eleven articles are focused on the topic but among the authors there is no consensus on the threshold for supplementation (ranging from 70% to 80%) as well as on the dose (rarely standardized) and time of administration (bolus vs continuous infusion). Consistently, antithrombin is considered able to achieve better anticoagulation targets in or not in the presence of heparin resistance. The impact of antithrombin administration on bleeding still shows contrasting results.

CONCLUSION

Antithrombin use in veno-venous extracorporeal membrane oxygenation should be investigated on the threshold for supplementation, dose, and time of administration.

Association between Five Common Plasminogen Activator Inhibitor-1 (PAI-1) Gene Polymorphisms and Colorectal Cancer Susceptibility

The plasminogen activator inhibitor-1 (PAI-1) is expressed in many cancer cell types and modulates cancer growth, invasion, and angiogenesis. The present study investigated the association between five PAI-1 gene polymorphisms and colorectal cancer (CRC) risk. Five PAI-1 polymorphisms (−844G > A [rs2227631], −675 4G > 5G [rs1799889], +43G > A [rs6092], +9785G > A [rs2227694], and +11053T > G [rs7242]) were genotyped using a polymerase chain reaction-restriction fragment length polymorphism assay in 459 CRC cases and 416 controls. Increased CRC risk was more frequently associated with PAI-1 −675 5G5G polymorphism than with 4G4G (adjusted odds ratio (AOR) = 1.556; 95% confidence interval (CI): 1.012–2.391; p = 0.04). In contrast, for the PAI-1 +11053 polymorphism, we found a lower risk of CRC with the GG genotype (AOR = 0.620; 95% CI: 0.413–0.932; p = 0.02) than with the TT genotype, as well as for recessive carriers (TT + TG vs. GG, AOR = 0.662; 95% CI: 0.469–0.933; p = 0.02). The +43AA genotype was associated with lower overall survival (OS) than the +43GG genotype. Our results suggest that the PAI-1 genotype plays a role in CRC risk. This is the first study to identify an association between five PAI-1 polymorphisms and CRC incidence worldwide.

Role of microRNAs in Venous Thromboembolism

MicroRNAs (miRNAs) are non-coding RNAs that execute their function by targeted downregulation of gene expressions. There is growing evidence from epidemiological studies and animal models suggesting that the expression level of miRNAs is dysregulated in venous thromboembolism (VTE). In this review, we summarize the current knowledge on the role of miRNAs as biomarkers for VTE and provide general insight into research exploring the modulation of miRNA activity in animal models of venous thrombosis. Up to now, published studies have yielded inconsistent results on the role of miRNAs as biomarkers for VTE with most of the reports focused on diagnostic research. The limited statistical power of the individual studies, due to the small sample sizes, may substantially contribute to the poor reproducibility among studies. In animal models, over-expression or inhibition of some miRNAs appear to influence venous thrombus formation and resolution. However, there is an important gap in knowledge on the potential role of miRNAs as therapeutic targets in VTE. Future research involving large cohorts should be designed to clarify the clinical usefulness of miRNAs as biomarkers for VTE, and animal model studies should be pursued to unravel the role of miRNAs in the pathogenesis of VTE and their potential as therapeutic targets.

Bayesian network analysis of plasma microRNA sequencing data in patients with venous thrombosis

MicroRNAs (miRNAs) are small regulatory RNAs participating to several biological processes and known to be involved in various pathologies. Measurable in body fluids, miRNAs have been proposed to serve as efficient biomarkers for diseases and/or associated traits. Here, we performed a next-generation-sequencing based profiling of plasma miRNAs in 344 patients with venous thrombosis (VT) and assessed the association of plasma miRNA levels with several haemostatic traits and the risk of VT recurrence. Among the most significant findings, we detected an association between hsa-miR-199b-3p and haematocrit levels (P = 0.0016), these two markers having both been independently reported to associate with VT risk. We also observed suggestive evidence for association of hsa-miR-370-3p (P = 0.019), hsa-miR-27b-3p (P = 0.016) and hsa-miR-222-3p (P = 0.049) with VT recurrence, the observations at the latter two miRNAs confirming the recent findings of Wang et al. Besides, by conducting Genome-Wide Association Studies on miRNA levels and meta-analyzing our results with some publicly available, we identified 21 new associations of single nucleotide polymorphisms with plasma miRNA levels at the statistical significance threshold of P < 5 × 10-8, some of these associations pertaining to thrombosis associated mechanisms. In conclusion, this study provides novel data about the impact of miRNAs' variability in haemostasis and new arguments supporting the association of few miRNAs with the risk of recurrence in patients with venous thrombosis.

Upregulated MiR-9-5p Protects Against Inflammatory Response in Rats with Deep Vein Thrombosis via Inhibition of NF-κB p50

Recently, microRNAs (miRNAs) have been demonstrated to play important roles in the cardiovascular system, including heart, blood vessels, plasma, and vascular diseases. Deep vein thrombosis (DVT) refers to the formation of blood clot in the deep veins of the human body and is a common peripheral vascular disease. Herein, we explored the mechanism of miR-9-5p in DVT through nuclear factor-κB (NF-κB). The expression of miR-9-5p in DVT rats was measured through the establishment of DVT rat models, followed by the alteration of miR-9-5p and NF-κB p50 in rats through the injection of constructed lentiviral vectors so as to explore the role of miR-9-5p and NF-κB p50 expression in rats. Next, the expression of NF-κB p50 and levels of inflammation-related factors plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and interleukin-8 (IL-8) were measured after the injection with lentiviral vectors, followed by the assessment of platelet aggregation and TXB2 content. MiR-9-5p was found to be downregulated in DVT rats. Through dual luciferase reporter gene assay, NF-κB p50 was verified as the target gene of miR-9-5p and miR-9-5p could negatively regulate NF-κB p50. MiR-9-5p over-expression decreased the levels of PAI-1, TNF-α, IL-6, and IL-8 and platelet aggregation as well as TXB2 content, thus inhibiting thrombosis. Meanwhile, over-expressed NF-κB p50 could reverse the anti-inflammatory or anti-thrombotic effect of miR-9-5p. In summary, miR-9-5p over-expression can suppress the NF-κB signaling pathway through p50 downregulation, thus alleviating inflammation and thrombosis in DVT rats. MiR-9-5p could serve as a potential therapeutic target for DVT.

MiR-421 Is Overexpressed and Promotes Cell Proliferation in Non-Small Cell Lung Cancer

BACKGROUND

Lung cancer is the main cause of cancer--related deaths worldwide, and the overall 5-year survival rate of non-small cell lung cancer (NSCLC) remained low. -MicroRNAs had been confirmed to be an important regulator in tumor progression, and they could serve as either tumor promoters or suppressors in NSCLC.

OBJECTIVES

To identify the novel cancer-specific biomarkers for NSCLC patients, which may be useful to monitor tumor progression and improve NSCLC patients' survival.

METHOD

The expression profile of miR-421 was analyzed in NSCLC samples using public datasets, including The Cancer Genome Atlas and GSE102286. The expression level of miR-421 was detected by reverse transcription-polymerase chain reaction. Cell proliferation and cell cycle were detected by Cell Counting Kit assay, flow cytometry assay, respectively. Kyoto Encyclopedia of Genes and Genomes analysis were applied to determine the biological roles of miR-421, based on the online DAVID system. Statistical comparisons between groups of normalized data were performed using t test or Mann-Whitney U test according to the test condition.

RESULTS

In this study, we focused on exploring the roles of miR-421 in NSCLC prognosis and growth. The present study for the first time showed that miR-421 was overexpressed in NSCLC and associated with a shorter overall survival time of patients with NSCLC. Bioinformatics analysis revealed miR-421 was involved in transcription, cell cycle, and insulin signaling pathway regulation. Furthermore, a gain of function assay showed that overexpression of miR-421 could promote NSCLC cell proliferation and cell cycle progression.

CONCLUSIONS

Our findings suggest that miR-421 might be a promising prognostic and therapeutic target for NSCLC.

Endothelial miR-30c suppresses tumor growth via inhibition of TGF-β-induced Serpine1

In tumors, extravascular fibrin forms provisional scaffolds for endothelial cell (EC) growth and motility during angiogenesis. We report that fibrin-mediated angiogenesis was inhibited and tumor growth delayed following postnatal deletion of Tgfbr2 in the endothelium of Cdh5-CreERT2 Tgfbr2fl/fl mice (Tgfbr2iECKO mice). ECs from Tgfbr2iECKO mice failed to upregulate the fibrinolysis inhibitor plasminogen activator inhibitor 1 (Serpine1, also known as PAI-1), due in part to uncoupled TGF-β-mediated suppression of miR-30c. Bypassing TGF-β signaling with vascular tropic nanoparticles that deliver miR-30c antagomiRs promoted PAI-1-dependent tumor growth and increased fibrin abundance, whereas miR-30c mimics inhibited tumor growth and promoted vascular-directed fibrinolysis in vivo. Using single-cell RNA-Seq and a NanoString miRNA array, we also found that subtypes of ECs in tumors showed spectrums of Serpine1 and miR-30c expression levels, suggesting functional diversity in ECs at the level of individual cells; indeed, fresh EC isolates from lung and mammary tumor models had differential abilities to degrade fibrin and launch new vessel sprouts, a finding that was linked to their inverse expression patterns of miR-30c and Serpine1 (i.e., miR-30chi Serpine1lo ECs were poorly angiogenic and miR-30clo Serpine1hi ECs were highly angiogenic). Thus, by balancing Serpine1 expression in ECs downstream of TGF-β, miR-30c functions as a tumor suppressor in the tumor microenvironment through its ability to promote fibrin degradation and inhibit blood vessel formation.

Synergistic effects of sulfur dioxide and polycyclic aromatic hydrocarbons on pulmonary pro-fibrosis via mir-30c-1-3p/ transforming growth factor β type II receptor axis

SO₂ and PAHs are well-known pollutants of coal burning and significant contributors to haze episodes. The purpose of the study is to determine whether the combined effects of SO₂ and BaP are synergetic and to investigate the pro-fibrotic influences and possible mechanism from the aspect of microRNAs. In the present study cellular metabolic activity of BEAS-2B was assessed using MTT probe. C57BL/6 mice were exposed to BaP (40 mg/kg b.w.) for 5 days or SO₂ (7 mg/m³) inhalation for 4 weeks alone or together. Lung tissues were processed for histology to assess pulmonary fibrosis. The protein level of pulmonary pro-fibrotic genes (Col1a1, Col3a1, alpha-SMA, fibronectin) and TGFβR2 were analyzed by Western blot and immunofluorescence in vivo and in vitro. Furthermore, we clarified that the microRNA expression of mir-30c-1-3p by real-time RT-PCR. The luciferase reporter assay was used to determine the binding sites of mir-30c-1-3p in the 3'-UTR of TGFβR2. It was confirmed that SO₂ and BaP acted together to produce synergistic effects in cellular metabolic activity. Coexisting of SO₂ and BaP increased the protein expression of pro-fibrotic genes and TGFβR2 and decreased mir-30c-1-3p in vivo and in vitro. Dual-luciferase reporter gene assays showed that TGFβR2 was a validated target of mir-30c-1-3p. All above results demonstrated that mir-30c-1-3p was involved in the synergistic pro-fibrotic effects of SO₂ and BaP in lung via targeting TGFβR2. This work implies the potential risk of pulmonary fibrosis from the co-existence of SO₂ and PAHs and provides new insights into the molecular markers for relevant diseases.

microRNAs in the haemostatic system: More than witnesses of thromboembolic diseases?

MicroRNAs (miRNAs) are small endogenous RNAs that post-transcriptionally regulate gene expression. In the last few years, these molecules have been implicated in the regulation of haemostasis, and an increasing number of studies have investigated their relationship with the development of thrombosis. In this review, we discuss the latest developments regarding the role of miRNAs in the regulation of platelet function and secondary haemostasis. We also discuss the genetic and environmental factors that regulate miRNAs. Finally, we address the potential use of miRNAs as prognostic and diagnostic tools in thrombosis.

MicroRNA-335-5p suppresses lower extremity deep venous thrombosis by targeted inhibition of PAI-1 via the TLR4 signalingpathway

This study aims to investigate the effects of microRNA-335-5p (miR-335-5p) on lower-extremity deep vein thrombosis (LEDVT) by targeting PAI-1 through the TLR4 signaling pathway in rat models. siRNA, mimic, and inhibitor were used for transfection. The miR-335-5p expression was detected by in situ hybridization. CCK-8 assay and flow cytometry were adopted to detect proliferation, cell cycle, and apoptosis, respectively. Scratch test and Matrigel-based tube formation assay were used to detect the effect of miR-335-5p on cell migration ability and tube formation ability. A miR-335-5p lentivirus plasmid was constructed and injected into LEDVT rats. The length and weight of thrombus were measured, changes of thrombus recanalization were observed by CD34 immunohistochemistry, and levels of PAI-1 and inflammatory factors in femoral vein blood were detected by ELISA. LEDVT rats showed a higher AOD value of PAI-1, higher expression of PAI-1, NF-κB, Rac1, IL-1β, and TLR4 and a lower miR-335-5p expression. PAI-1 and miR-335-5p were negatively correlated. Compared to the blank and siRNA-NC groups, the miR-335-5p mimic and siRNA-PAI-1 groups showed declined expression of PAI-1, TLR4, NF-κB, Rac1, and IL-1β, increased proliferation and tube formation abilities, less cells in G0/G1 phase, and decreased apoptosis, decreased length and weight of thrombus, organized thrombus, increased new blood vessels, and decreased levels of PAI-1, IL-1, IL-6, and Tnf-a. miR-335-5p may suppress the occurrence and development of LEDVT in rats by repressing the activation of the TLR4 signaling pathway by targeted inhibition of PAI-1.

What is currently known about the genetics of venous thromboembolism at the dawn of next generation sequencing technologies

Venous thromboembolism (VTE) has a strong genetic component. This review summarizes what is known at the seventeen genes that are now well established to harbour VTE-associated genetic variants. In addition, it discusses additional candidate genes that deserve further validation before being claimed as VTE associated genes. Finally, several research strategies are briefly described to identify other molecular determinants of the disease.

The role of microRNAs in prethrombotic status associated with coronary artery disease

The acute cardiovascular events following thrombus formation is a primary cause of morbidity and mortality of patients with coronary artery disease (CAD). Numerous studies have shown that a prethrombotic status, which can be defined as an imbalance between the procoagulant and anticoagulant conditions, would exist for a period of time before thrombogenesis. Therefore, early diagnosis and intervention of prethrombotic status are important for reducing acute cardiovascular events. However, none of prethrombotic indicators have been identified as golden standard for diagnosis of prethrombotic status to date. MicroRNAs (miRNAs), a class of short non-coding RNAs, have been shown to be involved in pathophysiologic processes related to prethrombotic status, such as endothelial dysfunction, platelet activation, impaired fibrinolysis and elevated procoagulant factors, etc. Owing to their multiple and fine-tuning impacts on gene expression, miRNAs raise a novel understanding in the underlying mechanism of prethrombotic status. This review aims to discuss the role of miRNAs in prethrombotic status, especially the differently expressed miRNAs in CAD, which may be meaningful for developing promising diagnostic biomarkers and therapeutic strategies for CAD patients in future.

Identification of coagulation gene 3'UTR variants that are potentially regulated by microRNAs

MicroRNAs have been recognized as critical regulators of gene expression and might affect the risk of venous thrombosis. We aimed to identify 3' untranslated region (UTR) variants in coagulation genes that influence coagulation factor levels and venous thrombosis risk. The 3'UTR of coagulation genes were sequenced in subjects with extremely high or low plasma levels of these factors in two case-control studies. In total, 28 variants were identified. Five single nucleotide polymorphisms (SNPs) were predominantly present in one extreme level group (F2 rs1799963, F8 rs1050705 and F11 rs4253429, rs4253430 and rs1062547). Additional to F2 rs1799963, F8 rs1050705 (in men) and F11 rs4253430 were associated with an increased risk of venous thrombosis albeit confidence intervals were wide. The three F11 SNPs were in high linkage disequilibrium with functional variants rs2289252 and rs2036914. Rs1062547 and rs4253430 were associated with a significant increase of plasma FXI activity in heterozygotes and homozygotes in wild-type controls. In silico prediction revealed that these SNPs might disturb the binding sites of miR-544 and miR-513a-3p. Only miR-544 provoked a significant decrease of the luciferase activity that was not observed with a rs4253430 mutated vector. In conclusion, these results reinforce that microRNAs are candidates to play a role in haemostasis and complex disorders, such as thrombosis.

Epigenetics in Reactive and Reparative Cardiac Fibrogenesis: The Promise of Epigenetic Therapy

Epigenetic changes play a pivotal role in the development of a wide spectrum of human diseases including cardiovascular diseases, cancer, diabetes, and intellectual disabilities. Cardiac fibrogenesis is a common pathophysiological process seen during chronic and stress-induced accelerated cardiac aging. While adequate production of extracellular matrix (ECM) proteins is necessary for post-injury wound healing, excessive synthesis and accumulation of extracellular matrix protein in the stressed or injured hearts causes decreased or loss of lusitropy that leads to cardiac failure. This self-perpetuating deposition of collagen and other matrix proteins eventually alter cellular homeostasis; impair tissue elasticity and leads to multi-organ failure, as seen during pathogenesis of cardiovascular diseases, chronic kidney diseases, cirrhosis, idiopathic pulmonary fibrosis, and scleroderma. In the last 25 years, multiple studies have investigated the molecular basis of organ fibrosis and highlighted its multi-factorial genetic, epigenetic, and environmental regulation. In this minireview, we focus on five major epigenetic regulators and discuss their central role in cardiac fibrogenesis. Additionally, we compare and contrast the epigenetic regulation of hypertension-induced reactive fibrogenesis and myocardial infarction-induced reparative or replacement cardiac fibrogenesis. As microRNAs-one of the major epigenetic regulators-circulate in plasma, we also advocate their potential diagnostic role in cardiac fibrosis. Lastly, we discuss the evolution of novel epigenetic-regulating drugs and predict their clinical role in the suppression of pathological cardiac remodeling, cardiac aging, and heart failure. J. Cell. Physiol. 232: 1941-1956, 2017. © 2016 Wiley Periodicals, Inc.

Non-Lethal Endotoxin Injection: A Rat Model of Hypercoagulability

Systemic inflammation co-activates coagulation, which unchecked culminates in a lethal syndrome of multi-organ microvascular thrombosis known as disseminated intravascular coagulation (DIC). We studied an endotoxin-induced inflammatory state in rats to identify biomarkers of hemostatic imbalance favoring hypercoagulability. Intraperitoneal injection of LPS at 15 mg/kg body weight resulted in peripheral leukopenia and widespread neutrophilic sequestration characteristic of an acute systemic inflammatory response. Early indicators of hemostatic pathway activation developed within 4 hours, including increased circulating concentrations of procoagulant extracellular vesicles (EVs), EVs expressing endothelial cell and platelet membrane markers, and high concentration of soluble intercellular adhesion molecule-1 (sICAM-1), plasminogen activator inhibitor-1 (PAI-1), and D-dimers. Inflammation persisted throughout the 48-hour observation period; however, increases were found in a subset of serum microRNA (miRNA) that coincided with gradual resolution of hemostatic protein abnormalities and reduction in EV counts. Dose-adjusted LPS treatment in rats provides a time-course model to develop biomarker profiles reflecting procoagulant imbalance and rebalance under inflammatory conditions.

Hyperglycaemia-induced reciprocal changes in miR-30c and PAI-1 expression in platelets

Type 2 diabetic mellitus (DM2) is associated with accelerated thrombotic complications and is characterized by high levels of plasminogen activator inhibitor-1 (PAI-1). Recent studies show that human platelets have high levels of miR-30c and synthesize considerable active PAI-1. The underlying mechanism of how PAI-1 expression is upregulated in DM2 is poorly understood. We now report that hyperglycaemia-induced repression of miR-30c increases PAI-1 expression and thrombus formation in DM2. Bioinformatic analysis and identification of miRNA targets were assessed using luciferase assays, quantitative real-time PCR and western blots invitro and in vivo. The changes in miR-30c and PAI-1 levels were identified in platelets from healthy and diabetic individuals. We found that miR-30c directly targeted the 3′ UTR of PAI-1 and negatively regulated its expression. miR-30c was negatively correlated with glucose and HbA1c levels in DM2. In HFD-fed diabetic mice, increasing miR-30c expression by lenti-miR-30c significantly decreased the PAI-1 expression and prolonged the time to occlusion in an arterial thrombosis model. Platelet depletion/reinfusion experiments generating mice with selective ablation of PAI-1 demonstrate a major contribution by platelet-derived PAI-1 in the treatment of lenti-miR-30c to thrombus formation. These results provide important implications regarding the regulation of fibrinolysis by platelet miRNA under diabetic mellitus.

The choice of endogenous controls in exosomal microRNA assessments from biofluids

The assessment of differentially expressed microRNAs in patients and healthy controls is important to identify potential tumor biomarkers. Recently, it has been shown that the microRNA levels in exosomes are more correlated with the clinical-pathological variables than vesicle-free microRNAs (miRNAs) in biofluids; therefore, there is an increasing interest in these specific evaluations. However, these measurements can be affected by experimental problems that not always are evaluated and/or by inadequate procedural choices. In particular, exosome isolation and miRNA extraction procedures are crucial to avoid contaminations, and even the choice of the most suitable purity controls is important. Moreover, a stable endogenous RNA should be used for normalization of miRNA expression obtained by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) in order to make these measures comparable among different samples. A rushed choice of the endogenous control can bias study conclusions without revealing inconsistencies. Unfortunately, a few studies systematically identified the best normalizer for their specific experimental context. Instead, sometimes, the normalization procedures were performed in a disputable way or the normalizer choices simply based on the previous literature. Here, we reviewed the studies where the exosomal miRNA profiling was assessed in human biofluids to point out the adopted procedures and the specific endogenous controls chosen for normalization.

Human Milk Cells Contain Numerous miRNAs that May Change with Milk Removal and Regulate Multiple Physiological Processes

Human milk (HM) is a complex biofluid conferring nutritional, protective and developmental components for optimal infant growth. Amongst these are maternal cells, which change in response to feeding and were recently shown to be a rich source of miRNAs. We used next generation sequencing to characterize the cellular miRNA profile of HM collected before and after feeding. HM cells conserved higher miRNA content than the lipid and skim HM fractions or other body fluids, in accordance with previous studies. In total, 1467 known mature and 1996 novel miRNAs were identified, with 89 high-confidence novel miRNAs. HM cell content was higher post-feeding (p < 0.05), and was positively associated with total miRNA content (p = 0.014) and species number (p < 0.001). This coincided with upregulation of 29 known and 2 novel miRNAs, and downregulation of 4 known and 1 novel miRNAs post-feeding, but no statistically significant change in expression was found for the remaining miRNAs. These findings suggest that feeding may influence the miRNA content of HM cells. The most highly and differentially expressed miRNAs were key regulators of milk components, with potential diagnostic value in lactation performance. They are also involved in the control of body fluid balance, thirst, appetite, immune response, and development, implicating their functional significance for the infant.

The role of microRNA-27a/b and microRNA-494 in estrogen-mediated downregulation of tissue factor pathway inhibitor α

Essentials Estrogens are known to influence the expression of microRNAs in breast cancer cells. We looked at microRNAs in estrogenic regulation of tissue factor pathway inhibitor α (TFPIα). Estrogen upregulated microRNA-27a/b and microRNA-494 through the estrogen receptor α. MicroRNA-27a/b and microRNA-494 are partly involved in estrogenic downregulation of TFPIα.

SUMMARY

Background Tissue factor pathway inhibitor (TFPI) has been linked to breast cancer pathogenesis. We have recently reported TFPI mRNA levels to be downregulated by estrogens in a breast cancer cell line (MCF7) through the estrogen receptor α (ERα). Accumulating evidence also indicates that activation of ERα signaling by estrogens may modulate the expression of target genes indirectly through microRNAs (miRNAs). Objectives To examine if miRNAs are involved in the estrogenic downregulation of TFPIα. Methods Computational analysis of the TFPI 3'-untranslated region (UTR) identified potential binding sites for miR-19a/b, miR-27a/b, miR-494, and miR-24. Transient overexpression or inhibition of the respective miRNAs was achieved by transfection of miRNA mimics or inhibitors. Direct targeting of TFPI 3'-UTR by miR-27a/b and miR-494 was determined by luciferase reporter assay in HEK293T cells. Effects of 17α-ethinylestradiol (EE2) and fulvestrant on relative miR-27a/b, miR-494, and TFPI mRNA levels in MCF7 cells were determined by qRT-PCR and secreted TFPIα protein by ELISA. Transient knockdown of ERα was achieved by siRNA transfection. Results EE2 treatment lead to a significant increase in miR-19a, miR-27a/b, miR-494, and miR-24 mRNA levels in MCF7 cells through ERα. miR-27a/b and miR-494 mimics lead to reduced TFPI mRNA and protein levels. Luciferase assay showed direct targeting of miR-27a/b and miR-494 on TFPI mRNA. Impaired estrogen-mediated downregulation of TFPI mRNA was detected in anti-miR-27a/b and anti-miR-494 transfected cells. Conclusions Our results provide evidence that miR-27a/b and miR-494 regulate TFPIα expression and suggest a possible role of these miRNAs in the estrogen-mediated downregulation of TFPIα.

Differential co-expression analysis of venous thromboembolism based on gene expression profile data

The aim of the present study was to screen differentially co-expressed genes and the involved transcription factors (TFs) and microRNAs (miRNAs) in venous thromboembolism (VTE). Microarray data of GSE19151 were downloaded from Gene Expression Omnibus, including 70 patients with VTE and 63 healthy controls. Principal component analysis (PCA) was performed using R software. Differential co-expression analysis was performed using R, followed by screening of modules using Cytoscape. Functional annotation was performed using Database for Annotation, Visualization, and Integrated Discovery. Moreover, Fisher test was used to screen key TFs and miRNAs for the modules. PCA revealed the disease and healthy samples could not be distinguished at the gene expression level. A total of 4,796 upregulated differentially co-expressed genes (e.g. zinc finger protein 264, electron-transfer-flavoprotein, beta polypeptide and Janus kinase 2) and 3,629 downregulated differentially co-expressed genes (e.g. adenylate cyclase 7 and single-stranded DNA binding protein 2) were identified, which were further mined to obtain 17 and eight modules separately. Functional annotation revealed that the largest upregulated module was primarily associated with acetylation and the largest downregulated module was mainly involved in mitochondrion. Moreover, 48 TFs and 62 miRNA families were screened for the 17 upregulated modules, such as E2F transcription factor 4, miR-30 and miR-135 regulating the largest module. Conversely, 35 TFs and 18 miRNA families were identified for the 8 downregulated modules, including mitochondrial ribosomal protein S12 and miR-23 regulating the largest module. Differentially co-expressed genes regulated by TFs and miRNAs may jointly contribute to the abnormal acetylation and mitochondrion presentation in the progression of VTE.

MicroRNAs for Fine-Tuning of Mouse Embryonic Stem Cell Fate Decision through Regulation of TGF-β Signaling

Over the past years, microRNAs (miRNAs) have emerged as crucial factors that regulate self-renewal and differentiation of embryonic stem cells (ESCs). Although much is known about their role in maintaining ESC pluripotency, the mechanisms by which they affect cell fate decisions remain poorly understood. By performing deep sequencing to profile miRNA expression in mouse ESCs (mESCs) and differentiated embryoid bodies (EBs), we identified four differentially expressed miRNAs. Among them, miR-191 and miR-16-1 are highly expressed in ESCs and repress Smad2, the most essential mediator of Activin-Nodal signaling, resulting in the inhibition of mesendoderm formation. miR-23a, which is also down-regulated in the differentiated state, suppresses differentiation toward the endoderm and ectoderm lineages. We further identified miR-421 as a differentiation-associated regulator through the direct repression of the core pluripotency transcription factor Oct4 and the bone morphogenetic protein (BMP)-signaling components, Smad5 and Id2. Collectively, our findings uncover a regulatory network between the studied miRNAs and both branches of TGF-β/BMP-signaling pathways, revealing their importance for ESC lineage decisions.

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miR-16-1 and miR-191 suppress mesendoderm differentiation by Activin/Smad2 targeting

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miR-23a represses endoderm and ectoderm differentiation

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miR-421 promotes ectoderm and endoderm differentiation by TGF-β and Oct4 inhibition

Therapeutic Potential of miR-494 in Thrombosis and Other Diseases: A Review

Functional nucleic acids, such as microRNAs (miRNAs), have been implicated in the pathophysiology of many diseases. The miRNA expression profiles of various cancers including haematological malignancies are well defined, but the role of miRNAs in haemostasis and the regulation of coagulation is poorly understood. We identified that miR-494 is oestrogen responsive and directly targets the anticoagulant protein, Protein S, as a mechanism for acquiring Protein S deficiency under high oestrogenic conditions such as during pregnancy and oral contraceptive use. Furthermore, previous studies have also characterised miR-494 to be involved in many biological processes. This paper reviews the current knowledge in the role of miRNAs in regulating haemostatic proteins and the known biological functions of miR-494, highlighting miR-494 as an emerging therapeutic target, with an overview of the strategy we have employed in identifying functional nucleic acids such as miRNAs that target haemostatic factors and the therapeutic potential of miR-494-directed therapy for the treatment of thrombotic disorders.

Noncoding RNAs, cytokines, and inflammation-related diseases

Chronic inflammation is involved in the onset and development of many diseases, including obesity, atherosclerosis, type 2 diabetes, osteoarthritis, autoimmune and degenerative diseases, asthma, periodontitis, and cirrhosis. The inflammation process is mediated by chemokines, cytokines, and different inflammatory cells. Although the molecules and mechanisms that regulate this primary defense mechanism are not fully understood, recent findings offer a putative role of noncoding RNAs, especially microRNAs (miRNAs), in the progression and management of the inflammatory response. These noncoding RNAs are crucial for the stability and maintenance of gene expression patterns that characterize some cell types, tissues, and biologic responses. Several miRNAs, such as miR-126, miR-132, miR-146, miR-155, and miR-221, have emerged as important transcriptional regulators of some inflammation-related mediators. Additionally, little is known about the involvement of long noncoding RNAs, long intergenic noncoding RNAs, and circular RNAs in inflammation-mediated processes and the homeostatic imbalance associated with metabolic disorders. These noncoding RNAs are emerging as biomarkers with diagnosis value, in prognosis protocols, or in the personalized treatment of inflammation-related alterations. In this context, this review summarizes findings in the field, highlighting those noncoding RNAs that regulate inflammation, with emphasis on recognized mediators such as TNF-α, IL-1, IL-6, IL-18, intercellular adhesion molecule 1, VCAM-1, and plasminogen activator inhibitor 1. The down-regulation or antagonism of the noncoding RNAs and the administration of exogenous miRNAs could be, in the near future, a promising therapeutic strategy in the treatment of inflammation-related diseases.

Dissociation of SERPINE1 mRNA from the translational repressor proteins Ago2 and TIA-1 upon platelet activation

Platelets play an important role in haemostasis, as well as in thrombosis and coagulation processes. They harbour a wide variety of messenger RNAs (mRNAs), that can template de novo protein synthesis, and an abundant array of microRNAs, which are known to mediate mRNA translational repression through proteins of the Argonaute (Ago) family. The relationship between platelet microRNAs and proteins capable of mediating translational repression, however, remains unclear. Here, we report that half of platelet microRNAs is associated to mRNA-regulatory Ago2 protein complexes, in various proportions. Associated to these Ago2 complexes are platelet mRNAs known to support de novo protein synthesis. Reporter gene activity assays confirmed the capacity of the platelet microRNAs, found to be associated to Ago2 complexes, to regulate translation of these platelet mRNAs through their 3'UTR. Neither the microRNA repertoire nor the microRNA composition of Ago2 complexes of human platelets changed upon activation with thrombin. However, under conditions favoring de novo synthesis of Plasminogen Activator Inhibitor-1 (PAI-1) protein, we documented a rapid dissociation of the encoding platelet SERPINE1 mRNA from Ago2 protein complexes as well as from the translational repressor protein T-cell-restricted intracellular antigen-1 (TIA-1). These findings are consistent with a scenario by which lifting of the repressive effects of Ago2 and TIA-1 protein complexes, involving a rearrangement of proteinmRNA complexes rather than disassembly of Ago2microRNA complexes, would allow translation of SERPINE1 mRNA into PAI-1 in response to platelet activation.

MicroRNAs in hemostasis

Epidemiologic studies have revealed that modification of the levels of individual components of the hemostatic system may have effects on the development of thrombosis or hemorrhage. To maintain the necessary equilibrium, the hemostatic system is finely regulated. It is known that acquired factors and/or alterations in genes (single-nucleotide polymorphisms or mutations) may be the cause of interindividual differences or exacerbated levels of hemostatic proteins in plasma, but there are still many non-characterized factors that provoke such variations. The search for new elements, such as microRNAs (miRNAs), a family of small non-coding RNAs that are novel regulators of protein expression, may reveal an additional layer at which to investigate the causes of hemostatic diseases. In this review, we discuss the latest developments in research into the role of miRNAs in the regulation of several hemostatic factors, and the potential use of miRNAs as prognostic or diagnostic tools in hemostasis and thrombosis.

Regulation of coagulation factor XI expression by microRNAs in the human liver

High levels of factor XI (FXI) increase the risk of thromboembolic disease. However, the genetic and environmental factors regulating FXI expression are still largely unknown. The aim of our study was to evaluate the regulation of FXI by microRNAs (miRNAs) in the human liver. In silico prediction yielded four miRNA candidates that might regulate FXI expression. HepG2 cells were transfected with miR-181a-5p, miR-23a-3p, miR-16-5p and miR-195-5p. We used mir-494, which was not predicted to bind to F11, as a negative control. Only miR-181a-5p caused a significant decrease both in FXI protein and F11 mRNA levels. In addition, transfection with a miR-181a-5p inhibitor in PLC/PRF/5 hepatic cells increased both the levels of F11 mRNA and extracellular FXI. Luciferase assays in human colon cancer cells deficient for Dicer (HCT-DK) demonstrated a direct interaction between miR-181a-5p and 3′untranslated region of F11. Additionally, F11 mRNA levels were inversely and significantly correlated with miR-181a-5p levels in 114 healthy livers, but not with miR-494. This study demonstrates that FXI expression is directly regulated by a specific miRNA, miR-181a-5p, in the human liver. Future studies are necessary to further investigate the potential consequences of miRNA dysregulation in pathologies involving FXI.

Regulation of NF-κB signaling by oxidized glycerophospholipid and IL-1β induced miRs-21-3p and -27a-5p in human aortic endothelial cells

Exposure of endothelial cells (ECs) to agents such as oxidized glycerophospholipids (oxGPs) and cytokines, known to accumulate in atherosclerotic lesions, perturbs the expression of hundreds of genes in ECs involved in inflammatory and other biological processes. We hypothesized that microRNAs (miRNAs) are involved in regulating the inflammatory response in human aortic endothelial cells (HAECs) in response to oxGPs and interleukin 1β (IL-1β). Using next-generation sequencing and RT-quantitative PCR, we characterized the profile of expressed miRNAs in HAECs pre- and postexposure to oxGPs. Using this data, we identified miR-21-3p and miR-27a-5p to be induced 3- to 4-fold in response to oxGP and IL-1β treatment compared with control treatment. Transient overexpression of miR-21-3p and miR-27a-5p resulted in the downregulation of 1,253 genes with 922 genes overlapping between the two miRNAs. Gene Ontology functional enrichment analysis predicted that the two miRNAs were involved in the regulation of nuclear factor κB (NF-κB) signaling. Overexpression of these two miRNAs leads to changes in p65 nuclear translocation. Using 3' untranslated region luciferase assay, we identified 20 genes within the NF-κB signaling cascade as putative targets of miRs-21-3p and -27a-5p, implicating these two miRNAs as modulators of NF-κB signaling in ECs.

Serum and amygdala microRNA signatures of posttraumatic stress: fear correlation and biomarker potential

Exposure to acute traumatic stress can cause permanent changes in neurological circuitry and may lead to the development of an anxiety disorder known as posttraumatic stress disorder (PTSD). Current diagnosis of PTSD is based on clinical or behavioral symptom assessment, however, these are not definitive due to overlapping symptoms with other psychiatric disorders or mild traumatic brain injury (mTBI). No FDA approved diagnostic tests or biomarkers are currently available for diagnosis of PTSD. Recently, circulating miRNAs have emerged as novel biomarkers of many diseases. In this study, we have examined the altered expression of serum and amygdala miRNAs in an animal model of PTSD. Differentially expressed and statistically significant miRNAs in serum were validated for their presence in amygdala of corresponding animals. A panel of nine stress-responsive miRNAs viz., miR-142-5p, miR-19b, miR-1928, miR-223-3p, miR-322∗, miR-324, miR-421-3p and miR-463∗ and miR-674∗ were identified, and may have potential as biomarker(s) for PTSD. Further validations by bioinformatics and system biology approaches indicate that five miRNAs such as miR-142-5p, miR-19b, miR-1928, miR-223 and miR-421-3p may play a potential role in the regulation of genes associated with delayed and exaggerated fear. To the best of our knowledge, this is the first report demonstrating the plausibility of using circulating miRNAs as biomarkers of PTSD.

Angiotensin-converting enzyme 2 is subject to post-transcriptional regulation by miR-421

ACE2 (angiotensin converting enzyme 2) plays a critical role in the local tissue RAS (renin-angiotensin system) by hydrolysing the potent hypertensive and mitogenic peptide AngII (angiotensin II). Changes in the levels of ACE2 have been observed in a number of pathologies, including cardiovascular disease, but little is known of the mechanisms regulating its expression. In the present study, therefore, the potential role of miRNAs in the regulation of ACE2 expression in primary human cardiac myofibroblasts was examined. Putative miRNA-binding sites were identified in the 3'-UTR of the ACE2 transcript using online prediction algorithms. Two of these, miR-200b and miR-421, were selected for further analysis. A reporter system using the 3'-UTR of ACE2 fused to the coding region of firefly luciferase was used to determine the functionality of the identified binding sites in vitro. This identified miR-421, but not miR-200b, as a potential regulator of ACE2. The ability of miR-421, an miRNA implicated in the development of thrombosis, to down-regulate ACE2 expression was subsequently confirmed by Western blot analysis of both primary cardiac myofibroblasts and transformed cells transfected with a synthetic miR-421 precursor. Real-time PCR analysis of miR-421 revealed widespread expression in human tissues. miR-421 levels in cardiac myofibroblasts showed significant inter-patient variability, in keeping with the variability of ACE2 expression we have observed previously. In conclusion, the present study is the first to demonstrate that ACE2 may be subject to post-transcriptional regulation and reveals a novel potential therapeutic target, miR-421, which could be exploited to modulate ACE2 expression in disease.

Cellular microRNAs and picornaviral infections

microRNAs (miRNAs) are a subtype of short, endogenous, and non-coding RNAs, which post-transcriptionally regulate gene expression. The miRNA-mediated gene silencing mechanism is involved in a wide spectrum of biological processes, such as cellular proliferation, differentiation, and immune responses. Picornaviridae is a large family of RNA viruses, which includes a number of causative agents of many human and animal diseases viz., poliovirus, foot-and-mouth disease virus (FMDV), and coxsackievirus B3 (CVB3). Accumulated evidences have demonstrated that replication of picornaviruses can be regulated by miRNAs and picornaviral infections can alter the expression of cellular miRNAs. Herein, we outline the intricate interactions between miRNAs and picornaviral infections.

Cardiomyocyte-specific miRNA-30c over-expression causes dilated cardiomyopathy

MicroRNAs (miRNAs) regulate many aspects of cellular function and their deregulation has been implicated in heart disease. MiRNA-30c is differentially expressed in the heart during the progression towards heart failure and in vitro studies hint to its importance in cellular physiology. As little is known about the in vivo function of miRNA-30c in the heart, we generated transgenic mice that specifically overexpress miRNA-30c in cardiomyocytes. We show that these mice display no abnormalities until about 6 weeks of age, but subsequently develop a severely dilated cardiomyopathy. Gene expression analysis of the miRNA-30c transgenic hearts before onset of the phenotype indicated disturbed mitochondrial function. This was further evident by the downregulation of mitochondrial oxidative phosphorylation (OXPHOS) complexes III and IV at the protein level. Taken together these data indicate impaired mitochondrial function due to OXPHOS protein depletion as a potential cause for the observed dilated cardiomyopathic phenotype in miRNA-30c transgenic mice. We thus establish an in vivo role for miRNA-30c in cardiac physiology, particularly in mitochondrial function.

Cytotoxicity and gene expression profiling of polyhexamethylene guanidine hydrochloride in human alveolar A549 cells

In Korea, lung disease of children and pregnant women associated with humidifier disinfectant use has become a major concern. A common sterilizer is polyhexamethylene guanidine (PHMG), a member of the guanidine family of antiseptics. This study was done to elucidate the putative cytotoxic effect of PHMG and the PHMG-mediated altered gene expression in human alveolar epithelial A549 cells in vitro. Cell viability analyses revealed the potent cytotoxicity of PHMG, with cell death evident at as low as 5 μg/mL. Death was dose- and time-dependent, and was associated with formation of intracellular reactive oxygen species, and apoptosis significantly, at even 2 μg/mL concentration. The gene expression profile in A549 cells following 24 h exposure to 5 μg/mL of PHMG was investigated using DNA microarray analysis. Changes in gene expression relevant to the progression of cell death included induction of genes related to apoptosis, autophagy, fibrosis, and cell cycle. However, the expressions of genes encoding antioxidant and detoxifying enzymes were down-regulated or not affected. The altered expression of selected genes was confirmed by quantitative reverse transcription-polymerase chain reaction and Western blot analyses. The collective data suggest that PHMG confers cellular toxicity through the generation of intracellular reactive oxygen species and alteration of gene expression.

Involvement of miR-30c in resistance to doxorubicin by regulating YWHAZ in breast cancer cells

MicroRNAs (miRNAs) are small RNA molecules that modulate gene expression implicated in cancer, which play crucial roles in diverse biological processes, such as development, differentiation, apoptosis, and proliferation. The aim of this study was to investigate whether miR-30c mediated the resistance of breast cancer cells to the chemotherapeutic agent doxorubicin (ADR) by targeting tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ). miR-30c was downregulated in the doxorubicin-resistant human breast cancer cell lines MCF-7/ADR and MDA-MB-231/ADR compared with their parental MCF-7 and MDA-MB-231 cell lines, respectively. Furthermore, we observed that transfection of an miR-30c mimic significantly suppressed the ability of MCF-7/ADR to resist doxorubicin. Moreover, the anti-apoptotic gene YWHAZ was confirmed as a target of miR-30c by luciferase reporter assay, and further studies indicated that the mechanism for miR-30c on the sensitivity of breast cancer cells involved YWHAZ and its downstream p38 mitogen-activated protein kinase (p38MAPK) pathway. Together, our findings provided evidence that miR-30c was one of the important miRNAs in doxorubicin resistance by regulating YWHAZ in the breast cancer cell line MCF-7/ADR.

Mechanisms of thrombosis in obesity

PURPOSE OF REVIEW

Obesity has become a worldwide epidemic that is driving increased morbidity and mortality from thrombotic disorders such as myocardial infarction, stroke, and venous thromboembolism. Effective prevention and treatment of thrombosis in obese patients is limited by an incomplete understanding of the underlying prothrombotic mechanisms and by uncertainties about risks, benefits, and dosing of anticoagulant drugs in this patient population.

RECENT FINDINGS

This review summarizes our current understanding of established and emerging mechanisms contributing to the obesity-induced prothrombotic state. The mechanistic impact of chronic inflammation and impaired fibrinolysis in mediating obesity-associated thrombosis is highlighted. Recent data demonstrating the aberrant expression of adipokines and microRNAs, which appear to function as key modulators of proinflammatory and prothrombotic pathways in obesity, are also reviewed. Finally, some challenges and new approaches to the prevention and management of thrombotic disorders in obese and overweight patients are discussed.

SUMMARY

Obesity-driven chronic inflammation and impaired fibrinolysis appear to be major effector mechanisms of thrombosis in obesity. The proinflammatory and hypofibrinolytic effects of obesity may be exacerbated by dysregulated expression and secretion of adipokines and microRNAs, which further increase the risk of thrombosis and suggest new potential targets for therapy.

Extracellular matrix secretion by cardiac fibroblasts: role of microRNA-29b and microRNA-30c

RATIONALE

MicroRNAs (miRNAs), in particular miR-29b and miR-30c, have been implicated as important regulators of cardiac fibrosis.

OBJECTIVE

To perform a proteomics comparison of miRNA effects on extracellular matrix secretion by cardiac fibroblasts.

METHODS AND RESULTS

Mouse cardiac fibroblasts were transfected with pre-/anti-miR of miR-29b and miR-30c, and their conditioned medium was analyzed by mass spectrometry. miR-29b targeted a cadre of proteins involved in fibrosis, including multiple collagens, matrix metalloproteinases, and leukemia inhibitory factor, insulin-like growth factor 1, and pentraxin 3, 3 predicted targets of miR-29b. miR-29b also attenuated the cardiac fibroblast response to transforming growth factor-β. In contrast, miR-30c had little effect on extracellular matrix production but opposite effects regarding leukemia inhibitory factor and insulin-like growth factor 1. Both miRNAs indirectly affected cardiac myocytes. On transfection with pre-miR-29b, the conditioned medium of cardiac fibroblasts lost its ability to support adhesion of rat ventricular myocytes and led to a significant reduction of cardiac myocyte proteins (α-actinin, cardiac myosin-binding protein C, and cardiac troponin I). Similarly, cardiomyocytes derived from mouse embryonic stem cells atrophied under pre-miR-29 conditioned medium, whereas pre-miR-30c conditioned medium had a prohypertrophic effect. Levels of miR-29a, miR-29c, and miR-30c, but not miR-29b, were significantly reduced in a mouse model of pathological but not physiological hypertrophy. Treatment with antagomiRs to miR-29b induced excess fibrosis after aortic constriction without overt deterioration in cardiac function.

CONCLUSIONS

Our proteomic analysis revealed novel molecular targets of miRNAs that are linked to a fibrogenic cardiac phenotype. Such comprehensive screening methods are essential to define the concerted actions of miRNAs in cardiovascular disease.