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1.
Sci Rep ; 14(1): 4514, 2024 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402278

RESUMO

Distinct patterns of circulating microRNAs (miRNAs) were found to be involved in misguided thrombus resolution. Thus, we aimed to investigate dysregulated miRNA signatures during the acute phase of pulmonary embolism (PE) and test their diagnostic and predictive value for future diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). Microarray screening and subsequent validation in a large patient cohort (n = 177) identified three dysregulated miRNAs as potential biomarkers: circulating miR-29a and miR-720 were significantly upregulated and miR-let7a was significantly downregulated in plasma of patients with PE. In a second validation study equal expression patterns for miR-29a and miR-let7a regarding an acute event of recurrent venous thromboembolism (VTE) or deaths were found. MiR-let7a concentrations significantly correlated with echocardiographic and laboratory parameters indicating right ventricular (RV) dysfunction. Additionally, circulating miR-let7a levels were associated with diagnosis of CTEPH during follow-up. Regarding CTEPH diagnosis, ROC analysis illustrated an AUC of 0.767 (95% CI 0.54-0.99) for miR-let7a. Using logistic regression analysis, a calculated patient-cohort optimized miR-let7a cut-off value derived from ROC analysis of ≥ 11.92 was associated with a 12.8-fold increased risk for CTEPH. Therefore, miR-let7a might serve as a novel biomarker to identify patients with haemodynamic impairment and as a novel predictor for patients at risk for CTEPH.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Embolia Pulmonar , Tromboembolia Venosa , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/complicações , Ecocardiografia/efeitos adversos , MicroRNAs/genética , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/genética , Biomarcadores , Tromboembolia Venosa/complicações , Doença Crônica
2.
Front Plant Sci ; 13: 962667, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267938

RESUMO

Pearl millet is an important cereal crop of semi-arid regions since it is highly nutritious and climate resilient. However, pearl millet is underutilized commercially due to the rapid onset of hydrolytic rancidity of seed lipids post-milling. We investigated the underlying biochemical and molecular mechanisms of rancidity development in the flour from contrasting inbred lines under accelerated aging conditions. The breakdown of storage lipids (triacylglycerols; TAG) was accompanied by free fatty acid accumulation over the time course for all lines. The high rancidity lines had the highest amount of FFA by day 21, suggesting that TAG lipases may be the cause of rancidity. Additionally, the high rancidity lines manifested substantial amounts of volatile aldehyde compounds, which are characteristic products of lipid oxidation. Lipases with expression in seed post-milling were sequenced from low and high rancidity lines. Polymorphisms were identified in two TAG lipase genes (PgTAGLip1 and PgTAGLip2) from the low rancidity line. Expression in a yeast model system confirmed these mutants were non-functional. We provide a direct mechanism to alleviate rancidity in pearl millet flour by identifying mutations in key TAG lipase genes that are associated with low rancidity. These genetic variations can be exploited through molecular breeding or precision genome technologies to develop elite pearl millet cultivars with improved flour shelf life.

3.
Front Genet ; 10: 1294, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038702

RESUMO

Genomic selection (GS) is an emerging methodology that helps select superior lines among experimental cultivars in plant breeding programs. It offers the opportunity to increase the productivity of cultivars by delivering increased genetic gains and reducing the breeding cycles. This methodology requires inexpensive and sufficiently dense marker information to be successful, and with whole genome sequencing, it has become an important tool in many crops. The recent assembly of the pearl millet genome has made it possible to employ GS models to improve the selection procedure in pearl millet breeding programs. Here, three GS models were implemented and compared using grain yield and dense molecular marker information of pearl millet obtained from two different genotyping platforms (C [conventional GBS RAD-seq] and T [tunable GBS tGBS]). The models were evaluated using three different cross-validation (CV) schemes mimicking real situations that breeders face in breeding programs: CV2 resembles an incomplete field trial, CV1 predicts the performance of untested hybrids, and CV0 predicts the performance of hybrids in unobserved environments. We found that (i) adding phenotypic information of parental inbreds to the calibration sets improved predictive ability, (ii) accounting for genotype-by-environment interaction also increased the performance of the models, and (iii) superior strategies should consider the use of the molecular markers derived from the T platform (tGBS).

4.
Plant Physiol Biochem ; 135: 546-553, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30447941

RESUMO

Pearl millet (Pennisetum glaucum) is the sixth-leading cereal crop and a staple food crop. It is known for its high tolerance to abiotic stress and good nutrient profile. NAC (NAM, ATAF1/2 and CUC) transcription factors (TFs) play an important role in abiotic stress tolerance. In our study, the pearl millet stress-responsive NAC TF gene PgNAC21 was characterized. Gene expression analysis revealed that PgNAC21 expression is induced by salinity stress and abscisic acid (ABA) treatment. In silico promoter analysis showed the presence of ABA response elements (ABREs) and MYB TF binding sites. A yeast one-hybrid assay indicated that a putative MYB TF in pearl millet, PgMYB1, binds to the promoter of PgNAC21. A transactivation assay in yeast cells revealed that PgNAC21 functions as a transcription activator and that its activation domain is located in its C-terminus. Relative to control plants, Arabidopsis plants overexpressing PgNAC21 exhibited better seed germination, heavier fresh weight and greater root length under salinity stress. Overexpression of PgNAC21 in Arabidopsis plants also enhanced the expression of stress-responsive genes such as GSTF6 (GLUTATHIONE S-TRANSFERASE 6), COR47 (COLD-REGULATED 47) and RD20 (RESPONSIVE TO DEHYDRATION 20). Our data demonstrate that PgNAC21 functions as a stress-responsive NAC TF and can be utilized in transgenic approaches for developing salinity stress tolerance in crop plants.


Assuntos
Arabidopsis/fisiologia , Pennisetum/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Arabidopsis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Pennisetum/genética , Pennisetum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Estresse Salino , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
5.
G3 (Bethesda) ; 8(7): 2513-2522, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29794163

RESUMO

Pearl millet is a non-model grain and fodder crop adapted to extremely hot and dry environments globally. In India, a great deal of public and private sectors' investment has focused on developing pearl millet single cross hybrids based on the cytoplasmic-genetic male sterility (CMS) system, while in Africa most pearl millet production relies on open pollinated varieties. Pearl millet lines were phenotyped for both the inbred parents and hybrids stage. Many breeding efforts focus on phenotypic selection of inbred parents to generate improved parental lines and hybrids. This study evaluated two genotyping techniques and four genomic selection schemes in pearl millet. Despite the fact that 6× more sequencing data were generated per sample for RAD-seq than for tGBS, tGBS yielded more than 2× as many informative SNPs (defined as those having MAF > 0.05) than RAD-seq. A genomic prediction scheme utilizing only data from hybrids generated prediction accuracies (median) ranging from 0.73-0.74 (1000-grain weight), 0.87-0.89 (days to flowering time), 0.48-0.51 (grain yield) and 0.72-0.73 (plant height). For traits with little to no heterosis, hybrid only and hybrid/inbred prediction schemes performed almost equivalently. For traits with significant mid-parent heterosis, the direct inclusion of phenotypic data from inbred lines significantly (P < 0.05) reduced prediction accuracy when all lines were analyzed together. However, when inbreds and hybrid trait values were both scored relative to the mean trait values for the respective populations, the inclusion of inbred phenotypic datasets moderately improved genomic predictions of the hybrid genomic estimated breeding values. Here we show that modern approaches to genotyping by sequencing can enable genomic selection in pearl millet. While historical pearl millet breeding records include a wealth of phenotypic data from inbred lines, we demonstrate that the naive incorporation of this data into a hybrid breeding program can reduce prediction accuracy, while controlling for the effects of heterosis per se allowed inbred genotype and trait data to improve the accuracy of genomic estimated breeding values for pearl millet hybrids.


Assuntos
Genoma de Planta , Genômica , Endogamia , Pennisetum/genética , Fenótipo , Algoritmos , Genômica/métodos , Genótipo , Hibridização Genética , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes , Seleção Genética
7.
Circulation ; 134(11): 817-32, 2016 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-27559042

RESUMO

BACKGROUND: Myocardial fibrosis is a feature of many cardiac diseases. We used proteomics to profile glycoproteins in the human cardiac extracellular matrix (ECM). METHODS: Atrial specimens were analyzed by mass spectrometry after extraction of ECM proteins and enrichment for glycoproteins or glycopeptides. RESULTS: ECM-related glycoproteins were identified in left and right atrial appendages from the same patients. Several known glycosylation sites were confirmed. In addition, putative and novel glycosylation sites were detected. On enrichment for glycoproteins, peptides of the small leucine-rich proteoglycan decorin were identified consistently in the flowthrough. Of all ECM proteins identified, decorin was found to be the most fragmented. Within its protein core, 18 different cleavage sites were identified. In contrast, less cleavage was observed for biglycan, the most closely related proteoglycan. Decorin processing differed between human ventricles and atria and was altered in disease. The C-terminus of decorin, important for the interaction with connective tissue growth factor, was detected predominantly in ventricles in comparison with atria. In contrast, atrial appendages from patients in persistent atrial fibrillation had greater levels of full-length decorin but also harbored a cleavage site that was not found in atrial appendages from patients in sinus rhythm. This cleavage site preceded the N-terminal domain of decorin that controls muscle growth by altering the binding capacity for myostatin. Myostatin expression was decreased in atrial appendages of patients with persistent atrial fibrillation and hearts of decorin null mice. A synthetic peptide corresponding to this decorin region dose-dependently inhibited the response to myostatin in cardiomyocytes and in perfused mouse hearts. CONCLUSIONS: This proteomics study is the first to analyze the human cardiac ECM. Novel processed forms of decorin protein core, uncovered in human atrial appendages, can regulate the local bioavailability of antihypertrophic and profibrotic growth factors.


Assuntos
Fibrilação Atrial/metabolismo , Decorina , Miostatina/antagonistas & inibidores , Peptídeos , Animais , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Decorina/química , Decorina/metabolismo , Decorina/farmacologia , Feminino , Células HEK293 , Átrios do Coração/metabolismo , Átrios do Coração/fisiopatologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Camundongos , Camundongos Mutantes , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miostatina/metabolismo , Peptídeos/síntese química , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Proteômica
8.
PLoS One ; 10(10): e0139305, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26431155

RESUMO

BACKGROUND AND AIM: Patients with primary sclerosing cholangitis (PSC) are at high risk for the development of cholangiocarcinoma (CC). Analysis of micro ribonucleic acid (MiRNA) patterns is an evolving research field in biliary pathophysiology with potential value in diagnosis and therapy. Our aim was to evaluate miRNA patterns in serum and bile of patients with PSC and/or CC. METHODS: Serum and bile from consecutive patients with PSC (n = 40 (serum), n = 52 (bile)), CC (n = 31 (serum), n = 19 (bile)) and patients with CC complicating PSC (PSC/CC) (n = 12 (bile)) were analyzed in a cross-sectional study between 2009 and 2012. As additional control serum samples from healthy individuals were analyzed (n = 12). The miRNA levels in serum and bile were determined with global miRNA profiling and subsequent miRNA-specific polymerase chain reaction-mediated validation. RESULTS: Serum analysis revealed significant differences for miR-1281 (p = 0.001), miR-126 (p = 0.001), miR-26a (p = 0.001), miR-30b (p = 0.001) and miR-122 (p = 0.034) between patients with PSC and patients with CC. All validated miRNAs were significantly lower in healthy individuals. MiR-412 (p = 0.001), miR-640 (p = 0.001), miR-1537 (p = 0.003) and miR-3189 (p = 0.001) were significantly different between patients with PSC and PSC/CC in bile. CONCLUSIONS: Patients with PSC and/or CC have distinct miRNA profiles in serum and bile. Furthermore, miRNA concentrations are different in bile of patients with CC on top of PSC indicating the potential diagnostic value of these miRNAs.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Bile/metabolismo , Colangiocarcinoma/metabolismo , Colangite Esclerosante/metabolismo , MicroRNAs/metabolismo , Neoplasias dos Ductos Biliares/sangue , Estudos de Casos e Controles , Colangiocarcinoma/sangue , Colangite Esclerosante/sangue , Humanos , MicroRNAs/sangue
9.
Eur Heart J ; 36(32): 2184-96, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25898844

RESUMO

AIMS: Osteopontin (OPN) is a multifunctional cytokine critically involved in cardiac fibrosis. However, the underlying mechanisms are unresolved. Non-coding RNAs are powerful regulators of gene expression and thus might mediate this process. METHODS AND RESULTS: OPN and miR-21 were significantly increased in cardiac biopsies of patients with myocardial fibrosis. Ang II infusion via osmotic minipumps led to specific miRNA regulations with miR-21 being strongly induced in wild-type (WT) but not OPN knockout (KO) mice. This was associated with enhanced cardiac collagen content, myofibroblast activation, ERK-MAP kinase as well as AKT signalling pathway activation and a reduced expression of Phosphatase and Tensin Homologue (PTEN) as well as SMAD7 in WT but not OPN KO mice. In contrast, cardiotropic AAV9-mediated overexpression of OPN in vivo further enhanced cardiac fibrosis. In vitro, Ang II induced expression of miR-21 in WT cardiac fibroblasts, while miR-21 levels were unchanged in OPN KO fibroblasts. As pri-miR-21 was also increased by Ang II, we studied potential involved upstream regulators; Electrophoretic Mobility Shift and Chromatin Immunoprecipitation analyses confirmed activation of the miR-21 upstream-transcription factor AP-1 by Ang II. Recombinant OPN directly activated miR-21, enhanced fibrosis, and activated the phosphoinositide 3-kinase pathway. Locked nucleic acid-mediated miR-21 silencing ameliorated cardiac fibrosis development in vivo. CONCLUSION: In cardiac fibrosis related to Ang II, miR-21 is transcriptionally activated and targets PTEN/SMAD7 resulting in increased fibroblast survival. OPN KO animals are protected from miR-21 increase and fibrosis development due to impaired AP-1 activation and fibroblast activation.


Assuntos
Angiotensina II/fisiologia , MicroRNAs/genética , Miocárdio/patologia , Osteopontina/fisiologia , Adenoviridae , Idoso , Animais , Sobrevivência Celular , Células Cultivadas , Colágeno/metabolismo , Feminino , Fibrose/genética , Inativação Gênica , Vetores Genéticos/administração & dosagem , Humanos , Técnicas In Vitro , Masculino , Camundongos Knockout , MicroRNAs/metabolismo , Miofibroblastos/fisiologia , Osteopontina/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Recombinantes/farmacologia , Fatores de Transcrição
10.
Eur J Heart Fail ; 17(4): 405-15, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25739750

RESUMO

AIMS: Differentiation of heart failure with reduced (HFrEF) or preserved (HFpEF) ejection fraction independent of echocardiography is challenging in the community. Diagnostic strategies based on monitoring circulating microRNA (miRNA) levels may prove to be of clinical value in the near future. The aim of this study was to identify a novel miRNA signature that could be a useful HF diagnostic tool and provide valuable clinical information on whether a patient has HFrEF or HFpEF. METHODS AND RESULTS: MiRNA biomarker discovery was carried out on three patient cohorts, no heart failure (no-HF), HFrEF, and HFpEF, using Taqman miRNA arrays. The top five miRNA candidates were selected based on differential expression in HFpEF and HFrEF (miR-30c, -146a, -221, -328, and -375), and their expression levels were also different between HF and no-HF. These selected miRNAs were further verified and validated in an independent cohort consisting of 225 patients. The discriminative value of BNP as a HF diagnostic could be improved by use in combination with any of the miRNA candidates alone or in a panel. Combinations of two or more miRNA candidates with BNP had the ability to improve significantly predictive models to distinguish HFpEF from HFrEF compared with using BNP alone (area under the receiver operating characteristic curve >0.82). CONCLUSION: This study has shown for the first time that various miRNA combinations are useful biomarkers for HF, and also in the differentiation of HFpEF from HFrEF. The utility of these biomarker combinations can be altered by inclusion of natriuretic peptide. MiRNA biomarkers may support diagnostic strategies in subpopulations of patients with HF.


Assuntos
Biomarcadores/sangue , Insuficiência Cardíaca/diagnóstico , MicroRNAs/sangue , Volume Sistólico/fisiologia , Disfunção Ventricular/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeos Natriuréticos
11.
Clin Chem ; 61(1): 191-201, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25294924

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) are novel intracellular noncoding ribonucleotides regulating gene expression. Intriguingly, these RNA transcripts are detectable and stable in the blood of patients with cancer and cardiovascular disease. We tested whether circulating lncRNAs in plasma of critically ill patients with acute kidney injury (AKI) at inception of renal replacement therapy were deregulated and might predict survival. METHODS: We performed a global lncRNA expression analysis using RNA isolated from plasma of patients with AKI, healthy controls, and ischemic disease controls. This global screen revealed several deregulated lncRNAs in plasma samples of patients with AKI. lncRNA-array-based alterations were confirmed in kidney biopsies of patients as well as in plasma of 109 patients with AKI, 30 age-matched healthy controls, and 30 disease controls by quantitative real-time PCR. RESULTS: Circulating concentrations of the novel intronic antisense lncRNA TrAnscript Predicting Survival in AKI (TapSAKI) (P < 0.0001) were detectable in kidney biopsies and upregulated in plasma of patients with AKI. Cox regression and Kaplan-Meier curve analysis revealed TapSAKI as an independent predictor of 28-day survival (P < 0.01). TapSAKI was enriched in tubular epithelial cells subjected to ATP depletion (P = 0.03). CONCLUSIONS: The alteration of circulating concentrations of lncRNAs in patients with AKI supports TapSAKI as a predictor of mortality in this patient cohort.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/genética , RNA Longo não Codificante/sangue , RNA Longo não Codificante/genética , Injúria Renal Aguda/mortalidade , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estado Terminal , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Nat Commun ; 3: 1078, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23011132

RESUMO

Pathological growth of cardiomyocytes (hypertrophy) is a major determinant for the development of heart failure, one of the leading medical causes of mortality worldwide. Here we show that the microRNA (miRNA)-212/132 family regulates cardiac hypertrophy and autophagy in cardiomyocytes. Hypertrophic stimuli upregulate cardiomyocyte expression of miR-212 and miR-132, which are both necessary and sufficient to drive the hypertrophic growth of cardiomyocytes. MiR-212/132 null mice are protected from pressure-overload-induced heart failure, whereas cardiomyocyte-specific overexpression of the miR-212/132 family leads to pathological cardiac hypertrophy, heart failure and death in mice. Both miR-212 and miR-132 directly target the anti-hypertrophic and pro-autophagic FoxO3 transcription factor and overexpression of these miRNAs leads to hyperactivation of pro-hypertrophic calcineurin/NFAT signalling and an impaired autophagic response upon starvation. Pharmacological inhibition of miR-132 by antagomir injection rescues cardiac hypertrophy and heart failure in mice, offering a possible therapeutic approach for cardiac failure.


Assuntos
Autofagia/genética , Cardiomegalia/genética , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , Oligonucleotídeos/genética , Animais , Antagomirs , Calcineurina/genética , Células Cultivadas , Masculino , Camundongos , Camundongos Transgênicos , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Basic Res Cardiol ; 107(5): 278, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22760500

RESUMO

Atrial fibrosis is important for the pathogenesis of atrial fibrillation (AF) but the underlying signal transduction is incompletely understood. We therefore studied the role of microRNA-21 (miR-21) and its downstream target Sprouty 1 (Spry1) during atrial fibrillation. Left atria (LA) from patients with AF showed a 2.5-fold increased expression of miR-21 compared to matched LA of patients in sinus rhythm. Increased miR-21 expression correlated positively with atrial collagen content and was associated with a reduced protein expression of Spry1 and increased expression of connective tissue growth factor (CTGF), lysyl oxidase and Rac1-GTPase. Neonatal cardiac fibroblasts treated with angiotensin II (AngII) or CTGF showed an increased miR-21 and decreased Spry1 expression. Pretreatment with an inhibitor of Rac1 GTPase, NSC23766, reduced the AngII-induced upregulation of miR-21. A small molecule inhibitor of lysyl oxidase, BAPN, prevented the AngII as well as the CTGF-induced miR-21 expression. Transgenic mice with cardiac overexpression of Rac1, which develop spontaneous AF and atrial fibrosis with increasing age, showed upregulation of miR-21 expression associated with reduced Spry1 expression. miR-21 expression and signalling in vivo were prevented by long-term treatment of the mice with statins. Direct inhibition of miR-21 by antagomir-21 prevented fibrosis of the atrial myocardium post-myocardial infarction. Left atria of patients with atrial fibrillation are characterized by upregulation of miR-21 und reduced expression of Spry1. Activation of Rac1 by angiotensin II leads to a CTGF- and lysyl oxidase-mediated increase of miR-21 expression contributing to structural remodelling of the atrial myocardium.


Assuntos
MicroRNAs/fisiologia , Angiotensina II/farmacologia , Animais , Fator de Crescimento do Tecido Conjuntivo/fisiologia , Proteínas Ricas em Prolina do Estrato Córneo/análise , RNA Helicases DEAD-box/fisiologia , Fibrose , Átrios do Coração/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/análise , Proteína-Lisina 6-Oxidase/fisiologia , Ribonuclease III/fisiologia , Proteínas rac1 de Ligação ao GTP/fisiologia
14.
J Mol Cell Cardiol ; 51(5): 872-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21806992

RESUMO

Circulating microRNAs may have diagnostic potential in acute coronary syndrome (ACS). Previous studies, however, were based on low patient numbers and could not assess the relation of microRNAs to clinical characteristics and their potential prognostic value. We thus assessed the diagnostic and prognostic value of cardiomyocyte-enriched microRNAs in the context of clinical variables and a sensitive myonecrosis biomarker in a larger ACS cohort. MiR-1, miR-133a, miR-133b, miR-208a, miR-208b, and miR-499 concentrations were measured by quantitative reverse transcription PCR in plasma samples obtained on admission from 444 patients with ACS. High-sensitivity troponin T (hsTnT) was measured by immunoassay. Patients were followed for 6 months regarding all-cause mortality. In a multiple linear regression analysis that included clinical variables and hsTnT, miR-1, miR-133a, miR-133b, and miR-208b were independently associated with hsTnT levels (all P<0.001). Patients with myocardial infarction presented with higher levels of miR-1, miR-133a, and miR-208b compared with patients with unstable angina. However, all six investigated microRNAs showed a large overlap between patients with unstable angina or myocardial infarction. MiR-133a and miR-208b levels were significantly associated with the risk of death in univariate and age- and gender-adjusted analyses. Both microRNAs lost their independent association with outcome upon further adjustment for hsTnT. The present study tempers speculations about the potential usefulness of cardiomyocyte-enriched microRNAs as diagnostic or prognostic markers in ACS.


Assuntos
Síndrome Coronariana Aguda/genética , Angina Instável/genética , Biomarcadores/sangue , MicroRNAs/sangue , Infarto do Miocárdio/genética , Troponina T/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/mortalidade , Angina Instável/sangue , Angina Instável/diagnóstico , Angina Instável/mortalidade , Feminino , Seguimentos , Alemanha , Humanos , Masculino , MicroRNAs/genética , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Análise de Regressão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Taxa de Sobrevida , Troponina T/genética
15.
Circulation ; 124(6): 720-30, 2011 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-21788589

RESUMO

BACKGROUND: Myocardial infarction leads to cardiac remodeling and development of heart failure. Insufficient myocardial capillary density after myocardial infarction has been identified as a critical event in this process, although the underlying mechanisms of cardiac angiogenesis are mechanistically not well understood. METHODS AND RESULTS: Here, we show that the small noncoding RNA microRNA-24 (miR-24) is enriched in cardiac endothelial cells and considerably upregulated after cardiac ischemia. MiR-24 induces endothelial cell apoptosis, abolishes endothelial capillary network formation on Matrigel, and inhibits cell sprouting from endothelial spheroids. These effects are mediated through targeting of the endothelium-enriched transcription factor GATA2 and the p21-activated kinase PAK4, which were identified by bioinformatic predictions and validated by luciferase gene reporter assays. Respective downstream signaling cascades involving phosphorylated BAD (Bcl-XL/Bcl-2-associated death promoter) and Sirtuin1 were identified by transcriptome, protein arrays, and chromatin immunoprecipitation analyses. Overexpression of miR-24 or silencing of its targets significantly impaired angiogenesis in zebrafish embryos. Blocking of endothelial miR-24 limited myocardial infarct size of mice via prevention of endothelial apoptosis and enhancement of vascularity, which led to preserved cardiac function and survival. CONCLUSIONS: Our findings indicate that miR-24 acts as a critical regulator of endothelial cell apoptosis and angiogenesis and is suitable for therapeutic intervention in the setting of ischemic heart disease.


Assuntos
Células Endoteliais/metabolismo , MicroRNAs/fisiologia , Infarto do Miocárdio/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Arteríolas/patologia , Capilares/patologia , Hipóxia Celular , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Colágeno , Combinação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/patologia , Fator de Transcrição GATA2/biossíntese , Fator de Transcrição GATA2/genética , Perfilação da Expressão Gênica , Insuficiência Cardíaca/etiologia , Heme Oxigenase-1/biossíntese , Heme Oxigenase-1/genética , Laminina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Infarto do Miocárdio/complicações , Infarto do Miocárdio/genética , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Oligorribonucleotídeos/farmacologia , Proteoglicanas , Interferência de RNA , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Esferoides Celulares , Remodelação Ventricular , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/genética , Quinases Ativadas por p21/biossíntese , Quinases Ativadas por p21/genética
16.
Clin J Am Soc Nephrol ; 6(7): 1540-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21700819

RESUMO

BACKGROUND AND OBJECTIVES: MicroRNAs (miRNAs) are small ribonucleotides regulating gene expression. MicroRNAs are present in the blood in a remarkably stable form. We tested whether circulating miRNAs in the plasma of critically ill patients with acute kidney injury (AKI) at the inception of renal replacement therapy are deregulated and may predict survival. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We profiled miRNAs using RNA isolated from the plasma of patients with AKI and healthy controls. The results were validated in 77 patients with acute kidney injury, 30 age-matched healthy controls, and 18 critically ill patients with acute myocardial infarction by quantitative real-time PCR. RESULTS: Circulating levels of miR-16 and miR-320 were downregulated in the plasma of kidney injury AKI patients, whereas miR-210 was upregulated compared with healthy controls (all P < 0.0001) and disease controls (miR-210 and miR-16: P < 0.0001; miR-320: P = 0.03). Cox regression (P < 0.05) and Kaplan-Meier curve analysis (P = 0.03) revealed miR-210 as an independent and powerful predictor of 28-day survival. CONCLUSIONS: Circulating miRNAs are altered in patients with kidney injury AKI. MiR-210 predicts mortality in this patient cohort and may serve as a novel biomarker AKI reflecting pathophysiological changes on a cellular level.


Assuntos
Injúria Renal Aguda/genética , Injúria Renal Aguda/mortalidade , MicroRNAs/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Adulto , Análise de Variância , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estado Terminal , Feminino , Marcadores Genéticos , Alemanha , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Modelos de Riscos Proporcionais , Terapia de Substituição Renal , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
18.
Circ Res ; 107(1): 138-43, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20489163

RESUMO

RATIONALE: The endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) is increased in patients with coronary artery disease and may regulate function of circulating angiogenic progenitor cells (APCs) by small regulatory RNAs. OBJECTIVES: To study the role of microRNAs in ADMA-mediated impairment of APCs. METHODS AND RESULTS: By using microarray analyses, we established microRNA expression profiles of human APCs. We used ADMA to induce APC dysfunction and found 16 deregulated microRNAs. We focused on miR-21, which was 3-fold upregulated by ADMA treatment. Overexpression of miR-21 in human APCs impaired migratory capacity. To identify regulated miR-21 targets, we used proteome analysis, using difference in-gel electrophoresis followed by mass spectrometric analysis of regulated proteins. We found that transfection of miR-21 precursors significantly repressed superoxide dismutase 2 in APCs, which resulted in increased intracellular reactive oxygen species concentration and impaired nitric oxide bioavailability. MiR-21 further repressed sprouty-2, leading to Erk Map kinase-dependent reactive oxygen species formation and APC migratory defects. Small interference RNA-mediated superoxide dismutase 2 or sprouty-2 reduction also increased reactive oxygen species formation and impaired APC migratory capacity. ADMA-mediated reactive oxygen species formation and APC dysfunction was rescued by miR-21 blockade. APCs from patients with coronary artery disease and high ADMA plasma levels displayed >4-fold elevated miR-21 levels, low superoxide dismutase 2 expression, and impaired migratory capacity, which could be normalized by miR-21 antagonism. CONCLUSIONS: We identified a novel miR-21-dependent mechanism of ADMA-mediated APC dysfunction. MiR-21 antagonism therefore emerges as an interesting strategy to improve dysfunctional APCs in patients with coronary artery disease.


Assuntos
Inibidores da Angiogênese/fisiologia , Arginina/análogos & derivados , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , MicroRNAs/fisiologia , Neovascularização Patológica/patologia , Neovascularização Patológica/prevenção & controle , Células-Tronco/metabolismo , Arginina/fisiologia , Doença da Artéria Coronariana/genética , Regulação da Expressão Gênica/fisiologia , Humanos , MicroRNAs/biossíntese , MicroRNAs/genética , Neovascularização Patológica/genética , Células-Tronco/citologia , Células-Tronco/patologia
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