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1.
Clin Sci (Lond) ; 134(2): 87-101, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31899480

RESUMO

Women with a history of preeclampsia (PE) have increased risk of cardiovascular disease (CVD) later in life. However, the molecular determinants underlying this risk remain unclear. We sought to understand how circulating miRNA levels are affected by prior PE, and related to biological pathways underpinning cardiovascular disease. RNA sequencing was used to profile plasma levels of 2578 miRNAs in a retrospective study of women with a history of PE or normotensive pregnancy, in two independent cohorts with either acute coronary syndrome (ACS) (n = 17-18/group) or no ACS (n = 20/group). Differential miRNA alterations were assessed in relation to a history of PE (within each cohort) or ACS (across cohorts), and compared with miRNAs previously reported to be altered during PE. A history of PE was associated with altered levels of 30 and 20 miRNAs in the ACS and non-ACS cohorts, respectively, whereas ACS exposure was associated with alterations in 259 miRNAs. MiR-206 was identified at the intersection of all comparisons relating to past/current PE and ACS exposure, and has previously been implicated in atherogenic activities related to hepatocytes, vascular smooth muscle cells and macrophages. Integration of all differentially altered miRNAs with their predicted and experimentally validated targets in silico revealed a number of highly targeted genes with potential atherogenic functions (including NFAT5, CCND2 and SMAD2), and one significantly enriched KEGG biological pathway (Wnt signaling) that was shared between all exposure groups. The present study provides novel insights into miRNAs, target genes and biological pathways that may underlie the long-term cardiovascular sequelae of PE.


Assuntos
Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/genética , MicroRNA Circulante/sangue , MicroRNAs/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/genética , Via de Sinalização Wnt , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/genética , Doenças Cardiovasculares/sangue , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Análise de Componente Principal , Via de Sinalização Wnt/genética
2.
Crit Care Med ; 47(7): 918-925, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30720538

RESUMO

OBJECTIVES: Cellular Immunotherapy for Septic Shock is the first-in-human clinical trial evaluating allogeneic mesenchymal stem/stromal cells in septic shock patients. Here, we sought to determine whether plasma cytokine profiles may provide further information into the safety and biological effects of mesenchymal stem/stromal cell treatment, as no previous study has conducted a comprehensive analysis of circulating cytokine levels in critically ill patients treated with mesenchymal stem/stromal cells. DESIGN: Phase 1 dose-escalation trial. PATIENTS: The interventional cohort (n = 9) of septic shock patients received a single dose of 0.3, 1.0, or 3.0 million mesenchymal stem/stromal cells/kg body weight (n = 3 per dose). The observational cohort received no mesenchymal stem/stromal cells (n = 21). INTERVENTIONS: Allogeneic bone marrow-derived mesenchymal stem/stromal cells. MEASUREMENTS AND MAIN RESULTS: Serial plasma samples were collected at study baseline prior to mesenchymal stem/stromal cell infusion (0 hr), 1 hour, 4 hours, 12 hours, 24 hours, and 72 hours after mesenchymal stem/stromal cell infusion/trial enrollment. Forty-nine analytes comprised mostly of cytokines along with several biomarkers were measured. We detected no significant elevations in a broad range of pro-inflammatory cytokines and biomarkers between the interventional and observational cohorts. Stratification of the interventional cohort by mesenchymal stem/stromal cell dose further revealed patient-specific and dose-dependent perturbations in cytokines, including an early but transient dampening of pro-inflammatory cytokines (e.g., interleukin-1ß, interleukin-2, interleukin-6, interleukin-8, and monocyte chemoattractant protein 1), suggesting that mesenchymal stem/stromal cell treatment may alter innate immune responses and underlying sepsis biology. CONCLUSIONS: A single infusion of up to 3 million cells/kg of allogeneic mesenchymal stem/stromal cells did not exacerbate elevated cytokine levels in plasma of septic shock patients, consistent with a safe response. These data also offer insight into potential biological mechanisms of mesenchymal stem/stromal cell treatment and support further investigation in larger randomized controlled trials.


Assuntos
Citocinas/biossíntese , Transplante de Células-Tronco Mesenquimais/métodos , Choque Séptico/metabolismo , Choque Séptico/terapia , Adulto , Biomarcadores , Relação Dose-Resposta a Droga , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Índice de Gravidade de Doença
3.
Am J Respir Crit Care Med ; 197(3): 337-347, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28960096

RESUMO

RATIONALE: In septic animal models mesenchymal stem (stromal) cells (MSCs) modulate inflammation, enhance tissue repair and pathogen clearance, and reduce death. OBJECTIVES: To conduct a phase I dose escalation trial of MSCs in septic shock with the primary objective of examining the safety and tolerability of MSCs. METHODS: We enrolled nine participants within 24 hours of admission to the ICU. A control cohort of 21 participants was enrolled before starting the MSC interventional cohort to characterize expected adverse events (AEs) and to serve as a comparator for the intervention cohort. Three separate MSC dose cohorts, with three participants per cohort, received a single intravenous dose of 0.3, 1.0, and 3.0 × 106 cells/kg. A prespecified safety plan monitored participants for the occurrence of AEs; cytokines were collected at prespecified time points. MEASUREMENTS AND MAIN RESULTS: Ages of participants in the interventional versus observational cohorts were median of 71 (range, 38-91) and 61 (range, 23-95). Acute Physiology and Chronic Health Evaluation scores were median of 25 (range, 11-28) and 26 (range, 17-32). MSC doses ranged from 19 to 250 million cells. There were no prespecified MSC infusion-associated or serious unexpected AEs, nor any safety or efficacy signals for the expected AEs or the measured cytokines between the interventional and observational cohorts. CONCLUSIONS: The infusion of freshly cultured allogenic bone marrow-derived MSCs, up to a dose of 3 million cells/kg (250 million cells), into participants with septic shock seems safe. Clinical trial registered with www.clinicaltrials.gov (NCT02421484).


Assuntos
Imunoterapia/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Choque Séptico/terapia , Adulto , Fatores Etários , Idoso , Aloenxertos , Intervalos de Confiança , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores Sexuais , Choque Séptico/diagnóstico , Choque Séptico/mortalidade , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
4.
Circulation ; 136(25): 2451-2467, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-28971999

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by abnormal growth and enhanced glycolysis of pulmonary artery endothelial cells. However, the mechanisms underlying alterations in energy production have not been identified. METHODS: Here, we examined the miRNA and proteomic profiles of blood outgrowth endothelial cells (BOECs) from patients with heritable PAH caused by mutations in the bone morphogenetic protein receptor type 2 (BMPR2) gene and patients with idiopathic PAH to determine mechanisms underlying abnormal endothelial glycolysis. We hypothesized that in BOECs from patients with PAH, the downregulation of microRNA-124 (miR-124), determined with a tiered systems biology approach, is responsible for increased expression of the splicing factor PTBP1 (polypyrimidine tract binding protein), resulting in alternative splicing of pyruvate kinase muscle isoforms 1 and 2 (PKM1 and 2) and consequently increased PKM2 expression. We questioned whether this alternative regulation plays a critical role in the hyperglycolytic phenotype of PAH endothelial cells. RESULTS: Heritable PAH and idiopathic PAH BOECs recapitulated the metabolic abnormalities observed in pulmonary artery endothelial cells from patients with idiopathic PAH, confirming a switch from oxidative phosphorylation to aerobic glycolysis. Overexpression of miR-124 or siRNA silencing of PTPB1 restored normal proliferation and glycolysis in heritable PAH BOECs, corrected the dysregulation of glycolytic genes and lactate production, and partially restored mitochondrial respiration. BMPR2 knockdown in control BOECs reduced the expression of miR-124, increased PTPB1, and enhanced glycolysis. Moreover, we observed reduced miR-124, increased PTPB1 and PKM2 expression, and significant dysregulation of glycolytic genes in the rat SUGEN-hypoxia model of severe PAH, characterized by reduced BMPR2 expression and endothelial hyperproliferation, supporting the relevance of this mechanism in vivo. CONCLUSIONS: Pulmonary vascular and circulating progenitor endothelial cells isolated from patients with PAH demonstrate downregulation of miR-124, leading to the metabolic and proliferative abnormalities in PAH ECs via PTPB1 and PKM1/PKM2. Therefore, the manipulation of this miRNA or its targets could represent a novel therapeutic approach for the treatment of PAH.


Assuntos
Hipertensão Pulmonar Primária Familiar/patologia , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , MicroRNAs/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Piruvato Quinase/metabolismo , Animais , Antagomirs/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/antagonistas & inibidores , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/metabolismo , Glicólise , Ribonucleoproteínas Nucleares Heterogêneas/antagonistas & inibidores , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Quinases Lim/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/antagonistas & inibidores , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Piruvato Quinase/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Simportadores/metabolismo
5.
Thorax ; 73(3): 248-261, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28947667

RESUMO

BACKGROUND: Elevated plasma levels of angiopoietin-2 (ANGPT2) have been reported in patients with acute lung injury (ALI); however, it remains unclear whether this increase contributes to, or just marks, the underlying vasculopathic inflammation and leak associated with ALI. Here we investigated the biological consequences of inducing high circulating levels of ANGPT2 in a mouse model of endotoxin-induced ALI. METHODS: Transgenic mice (ANGPT2OVR) with elevated circulating levels of ANGPT2, achieved through conditional hepatocyte-specific overexpression, were examined from 3 to 72 hours following lipopolysaccharide (LPS)-induced ALI. An aptamer-based inhibitor was used to neutralise the effects of circulating ANGPT2 in LPS-exposed ANGPT2OVR mice. RESULTS: Total cells, neutrophils and macrophages, as well as inflammatory cytokines, were significantly higher in bronchoalveolar lavage (BAL) of ANGPT2OVR versus littermate controltTA mice at 48 hours and 6 hours post-LPS, respectively. In contrast, LPS-induced vascular leak, evidenced by total BAL protein levels and lung wet/dry ratio, was unchanged between ANGPT2OVR and controlstTA, while BAL levels of IgM and albumin were decreased in ANGPT2OVR mice between 24 hours and 48 hours suggesting a partial attenuation of vascular leak. There was no significant difference in LPS-induced mortality between ANGPT2OVR and controlstTA. An ANGPT2-neutralising aptamer partially attenuated alveolar cell infiltration while exacerbating vascular leak in LPS-exposed ANGPT2OVR mice, supported by underlying time-dependent changes in the lung transcriptional profiles of multiple genes linked to neutrophil recruitment/adhesion and endothelial integrity. CONCLUSIONS: Our findings suggest that high circulating ANGPT2 potentiates endotoxin-induced lung inflammation but may also exert other pleiotropic effects to help fine-tune the vascular response to lung injury.


Assuntos
Lesão Pulmonar Aguda/sangue , Angiopoietina-2/sangue , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/metabolismo , Pulmão/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Taxa de Sobrevida
6.
Elife ; 122023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37078698

RESUMO

We sought to define the mechanism underlying lung microvascular regeneration in a model of severe acute lung injury (ALI) induced by selective lung endothelial cell ablation. Intratracheal instillation of DT in transgenic mice expressing human diphtheria toxin (DT) receptor targeted to ECs resulted in ablation of >70% of lung ECs, producing severe ALI with near complete resolution by 7 days. Using single-cell RNA sequencing, eight distinct endothelial clusters were resolved, including alveolar aerocytes (aCap) ECs expressing apelin at baseline and general capillary (gCap) ECs expressing the apelin receptor. At 3 days post-injury, a novel gCap EC population emerged characterized by de novo expression of apelin, together with the stem cell marker, protein C receptor. These stem-like cells transitioned at 5 days to proliferative endothelial progenitor-like cells, expressing apelin receptor together with the pro-proliferative transcription factor, Foxm1, and were responsible for the rapid replenishment of all depleted EC populations by 7 days post-injury. Treatment with an apelin receptor antagonist prevented ALI resolution and resulted in excessive mortality, consistent with a central role for apelin signaling in EC regeneration and microvascular repair. The lung has a remarkable capacity for microvasculature EC regeneration which is orchestrated by newly emergent apelin-expressing gCap endothelial stem-like cells that give rise to highly proliferative, apelin receptor-positive endothelial progenitors responsible for the regeneration of the lung microvasculature.


Assuntos
Lesão Pulmonar Aguda , Apelina , Pulmão , Animais , Camundongos , Medicina Regenerativa , Apelina/genética , Apelina/metabolismo , Células Endoteliais , Camundongos Transgênicos , Pulmão/irrigação sanguínea
7.
Metabolites ; 13(11)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37999238

RESUMO

Sepsis is the result of an uncontrolled host inflammatory response to infection that may lead to septic shock with multiorgan failure and a high mortality rate. There is an urgent need to improve early diagnosis and to find markers identifying those who will develop septic shock and certainly a need to develop targeted treatments to prevent septic shock and its high mortality. Herein, we explore metabolic alterations due to mesenchymal stromal cell (MSC) treatment of septic shock. The clinical findings for this study were already reported; MSC therapy was well-tolerated and safe in patients in this phase I clinical trial. In this exploratory metabolomics study, 9 out of 30 patients received an escalating dose of MSC treatment, while 21 patients were without MSC treatment. Serum metabolomics profiling was performed to detect and characterize metabolite changes due to MSC treatment and to help determine the sample size needed for a phase II clinical trial and to define a metabolomic response to MSC treatment. Serum metabolites were measured using 1H-NMR and HILIC-MS at times 0, 24 and 72 h after MSC infusion. The results demonstrated the significant impact of MSC treatment on serum metabolic changes in a dose- and time-dependent manner compared to non-MSC-treated septic shock patients. This study suggests that plasma metabolomics can be used to assess the response to MSC therapy and that treatment-related metabolomics effects can be used to help determine the sample size needed in a phase II trial. As this study was not powered to detect outcome, how the treatment-induced metabolomic changes described in this study of MSC-treated septic shock patients are related to outcomes of septic shock in the short and long term will need to be explored in a larger adequately powered phase II clinical trial.

8.
Nucleic Acids Res ; 37(2): 413-20, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19050014

RESUMO

Single-stranded DNA molecules have the capacity to adopt catalytically active structures known as DNAzymes, although the fundamental limits of this ability have not been determined. Starting with a parent DNAzyme composed of all four types of standard nucleotides, we conducted a search of the surrounding sequence space to identify functional derivatives with catalytic cores composed of only three, and subsequently only two types of nucleotides. We provide the first report of a DNAzyme that contains only guanosine and cytidine deoxyribonucleotides in its catalytic domain, which consists of just 13 nucleotides. This DNAzyme catalyzes the Mn(2+)-dependent cleavage of an RNA phosphodiester bond approximately 5300-fold faster than the corresponding uncatalyzed reaction, but approximately 10,000-fold slower than the parent. The demonstration of a catalytic DNA molecule made from a binary nucleotide alphabet broadens our understanding of the fundamental limits of nucleic-acid-mediated catalysis.


Assuntos
Nucleotídeos de Citosina/química , DNA Catalítico/química , Nucleotídeos de Guanina/química , Biocatálise , Metais/química , RNA/química , RNA/metabolismo
9.
Nucleic Acids Res ; 37(11): 3545-57, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19357090

RESUMO

Herein, we describe a case study into the population dynamics of in vitro selection, using RNA-cleaving DNAzymes as a model system. We sought to understand how the composition of the population can change over time in response to different levels of selection pressure, and how well these changes are correlated with selection of the target phenotype. The model population is composed of 857 DNAzyme clones representing 215 discrete sequence classes, which had previously been identified from two parallel selection experiments, conducted under an increasingly stringent, or permissive and constant selection time pressure. In this report, we determined the principal phenotypic properties (i.e. k(obs), maximum cleavage yield and PCR efficiency) from a sample of 58 clones representing 46 different major and minor sequence classes from various rounds of each selection experiment. Interestingly, a positive correlation between the catalytic rate constant and the corresponding frequency and temporal position of a given DNAzyme was not consistently observed; however, the strength of the correlation was qualitatively higher under conditions of more stringent selection time pressure. These results suggest that the selective sampling paradigm on which in vitro selection is based, may underestimate the true functional capacity of any given random-sequence library.


Assuntos
DNA Catalítico/química , Evolução Molecular Direcionada , RNA/metabolismo , Catálise , DNA Catalítico/classificação , DNA Catalítico/metabolismo , Genótipo , Fenótipo , Reação em Cadeia da Polimerase
10.
Chembiochem ; 11(7): 866-79, 2010 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-20213779

RESUMO

Enzymes play a crucial role in all living organisms by accelerating the rates of a myriad of biochemical reactions that are necessary to sustain life. Although the vast majority of known enzymes are made of protein, in recent years it has become increasingly apparent that other molecular formats, like nucleic acids, can also serve in this capacity. DNAzymes (also known as deoxyribozymes) are synthetic enzymes made of short, single strands of deoxyribonucleic acid. These DNA-based enzymes offer the prospect of significant commercial utility, because they are exceptionally stable and can be produced very easily and inexpensively. The study of one particular DNAzyme, known as "8-17", has enhanced our understanding of DNAzyme-mediated catalysis. Moreover, the function of 8-17 has been regarded with special importance because it can catalyze sequence-specific cleavage of RNA, a reaction that has broad implications in biotechnology and biomedical fields. In this review, we explore the creation, characterization, and application of the 8-17 RNA-cleaving DNAzyme.


Assuntos
DNA Catalítico/química , DNA Catalítico/metabolismo , Endorribonucleases/química , Endorribonucleases/metabolismo , Biocatálise , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Metais/química , Conformação de Ácido Nucleico , RNA/química , RNA/metabolismo , Estereoisomerismo , Especificidade por Substrato
11.
Nucleic Acids Res ; 36(5): 1472-81, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18203744

RESUMO

Many sequence variations of the 8-17 RNA-cleaving deoxyribozyme have been isolated through in vitro selection. In an effort to understand how these sequence variations affect cleavage site selectivity, we systematically mutated the catalytic core of 8-17 and measured the cleavage activity of each mutant deoxyribozyme against all 16 possible chimeric (RNA/DNA) dinucleotide junctions. We observed sequence-function relationships that suggest how the following non-conserved positions in the catalytic core influence selectivity at the dinucleotide (5' rN(18)-N(1.1) 3') cleavage site: (i) positions 2.1 and 12 represent a primary determinant of the selectivity at the 3' position (N(1.1)) of the cleavage site; (ii) positions 15 and 15.0 represent a primary determinant of the selectivity at the 5' position (rN(18)) of the cleavage site and (iii) the sequence of the 3-bp intramolecular stem has relatively little influence on cleavage site selectivity. Furthermore, we report for the first time that 8-17 variants have the collective ability to cleave all dinucleotide junctions with rate enhancements of at least 1000-fold over background. Three optimal 8-17 variants, identified from approximately 75 different sequences that were examined, can collectively cleave 10 of 16 junctions with useful rates of >/=0.1 min(-1), and exhibit an overall hierarchy of reactivity towards groups of related junctions according to the order NG > NA > NC > NT.


Assuntos
DNA Catalítico/química , RNA/metabolismo , Sequência de Bases , Catálise , DNA Catalítico/metabolismo , Cinética , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Nucleotídeos/metabolismo , RNA/química , Relação Estrutura-Atividade
12.
Nucleic Acids Res ; 36(14): 4768-77, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18644842

RESUMO

Herein, we sought new or improved endoribonucleases based on catalytic DNA molecules known as deoxyribozymes. The current repertoire of RNA-cleaving deoxyribozymes can cleave nearly all of the 16 possible dinucleotide junctions with rates of at least 0.1/min, with the exception of pyrimidine-pyrimidine (pyr-pyr) junctions, which are cleaved 1-3 orders of magnitude slower. We conducted four separate in vitro selection experiments to target each pyr-pyr dinucleotide combination (i.e. CC, UC, CT and UT) within a chimeric RNA/DNA substrate. We used a library of DNA molecules containing only 20 random-sequence nucleotides, so that all possible sequence permutations could be sampled in each experiment. From a total of 245 clones, we identified 22 different sequence families, of which 21 represented novel deoxyribozyme motifs. The fastest deoxyribozymes exhibited k(obs) values (single-turnover, intermolecular format) of 0.12/min, 0.04/min, 0.13/min and 0.15/min against CC, UC, CT and UT junctions, respectively. These values represent a 6- to 8-fold improvement for CC and UC junctions, and a 1000- to 1600-fold improvement for CT and UT junctions, compared to the best rates reported previously under identical reaction conditions. The same deoxyribozymes exhibited approximately 1000-fold lower activity against all RNA substrates, but could potentially be improved through further in vitro evolution and engineering.


Assuntos
DNA Catalítico/química , Nucleotídeos de Pirimidina/metabolismo , RNA/metabolismo , DNA Catalítico/metabolismo , Evolução Molecular Direcionada/métodos , Biblioteca Gênica , Metais/química , Nucleotídeos de Pirimidina/química , RNA/química
13.
Cardiovasc Res ; 116(6): 1113-1124, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31782762

RESUMO

The aim of this systematic review was to assess dysregulated miRNA biomarkers in coronary artery disease (CAD). Dysregulated microRNA (miRNAs) have been shown to be linked to cardiovascular pathologies including CAD and may have utility as diagnostic and prognostic biomarkers. We compared miRNAs identified in acute coronary syndrome (ACS) compared with stable CAD and control populations. We conducted a systematic search of controlled vocabulary and free text terms related to ACS, stable CAD and miRNA in Biosis Previews (OvidSP), The Cochrane Library (Wiley), Embase (OvidSP), Global Health (OvidSP), Medline (PubMed and OvidSP), Web of Science (Clarivate Analytics), and ClinicalTrials.gov which yielded 7370 articles. Of these, 140 original articles were appropriate for data extraction. The most frequently reported miRNAs in any CAD (miR-1, miR-133a, miR-208a/b, and miR-499) are expressed abundantly in the heart and play crucial roles in cardiac physiology. In studies comparing ACS cases with stable CAD patients, miR-21, miR-208a/b, miR-133a/b, miR-30 family, miR-19, and miR-20 were most frequently reported to be dysregulated in ACS. While a number of miRNAs feature consistently across studies in their expression in both ACS and stable CAD, when compared with controls, certain miRNAs were reported as biomarkers specifically in ACS (miR-499, miR-1, miR-133a/b, and miR-208a/b) and stable CAD (miR-215, miR-487a, and miR-502). Thus, miR-21, miR-133, and miR-499 appear to have the most potential as biomarkers to differentiate the diagnosis of ACS from stable CAD, especially miR-499 which showed a correlation between the level of their concentration gradient and myocardial damage. Although these miRNAs are potential diagnostic biomarkers, these findings should be interpreted with caution as the majority of studies conducted predefined candidate-driven assessments of a limited number of miRNAs (PROSPERO registration: CRD42017079744).


Assuntos
Síndrome Coronariana Aguda/sangue , MicroRNA Circulante/sangue , Doença da Artéria Coronariana/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , MicroRNA Circulante/genética , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/genética , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes
15.
Nucleic Acids Res ; 34(8): 2445-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16682452

RESUMO

We previously conducted an in vitro selection experiment for RNA-cleaving deoxyribozymes, using a combinatorial DNA library containing 80 random nucleotides. Ultimately, 110 different sequence classes were isolated, but the vast majority contained a short14-15 nt catalytic DNA motif commonly known as 8-17. Herein, we report extensive truncation experiments conducted on multiple sequence classes to confirm the suspected catalytic role played by 8-17 and to determine the effect of excess sequence elements on the activity of this motif and the outcome of selection. Although we observed beneficial, detrimental and neutral consequences for activity, the magnitude of the effect rarely exceeded 2-fold. These deoxyribozymes appear to have survived increasing selection pressure despite the presence of additional sequence elements, rather than because of them. A new deoxyribozyme with comparable activity, called G15-30, was approximately 2.5-fold larger and experienced a approximately 4-fold greater inhibitory effect from excess sequence elements than the average 8-17 motif. Our results suggest that 8-17 may be less susceptible to the potential inhibitory effects of excess arbitrary sequence than larger motifs, which represents a previously unappreciated selective advantage that may contribute to its widespread recurrence.


Assuntos
DNA Catalítico/química , RNA/metabolismo , Técnica de Seleção de Aptâmeros , Sequência de Bases , Domínio Catalítico , DNA Catalítico/metabolismo , Genótipo , Cinética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Fenótipo , Deleção de Sequência
16.
Theranostics ; 8(5): 1213-1226, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29507615

RESUMO

There is considerable interest in the use of synthetic miRNA mimics (or inhibitors) as potential therapeutic agents in pulmonary vascular disease; however, the optimal delivery method to achieve high efficiency, selective lung targeting has not been determined. Here, we sought to investigate the relative merits of different lung-targeted strategies for delivering miRNA mimics in rats. Methods: Tissue levels of a synthetic miRNA mimic, cel-miR-39-3p (0.5 nmol in 50 µL invivofectamine/PBS vehicle) were compared in male rats (n=3 rats/method) after delivery by commonly used lung-targeting strategies including intratracheal liquid instillation (IT-L), intratracheal aerosolization with (IT-AV) or without ventilator assistance (IT-A), intranasal liquid instillation (IN-L) and intranasal aerosolization (IN-A). Intravenous (IV; via jugular vein), intraperitoneal (IP) and subcutaneous (SC) delivery served as controls. Relative levels of cel-miR-39 were quantified by RT-qPCR. Results: At 2 h post delivery, IT-L showed the highest lung mimic level, which was significantly higher than levels achieved by all other methods (from ~10- to 10,000-fold, p<0.05). Mimic levels remained detectable in the lung 24 h after delivery, but were 10- to 100-fold lower. The intrapulmonary distribution of cel-miR-39 was comparable when delivered as either a liquid or aerosol, with evidence of mimic distribution to both the left and right lung lobes and penetration to distal regions. All lung-targeted strategies showed lung-selective mimic uptake, with mimic levels 10- to 100-fold lower in heart and 100- to 10,000-fold lower in liver, kidney and spleen. In contrast, IV, SC and IP routes showed comparable or higher mimic levels in non-pulmonary tissues. Conclusions: miRNA uptake in the lungs differed markedly by up to 4 orders of magnitude, demonstrating that the choice of delivery strategy could have a significant impact on potential therapeutic outcomes in preclinical investigations of miRNA-based drug candidates.


Assuntos
Técnicas de Transferência de Genes , Pulmão/metabolismo , MicroRNAs/administração & dosagem , Animais , Citocinas/metabolismo , Vias de Administração de Medicamentos , Sistemas de Liberação de Medicamentos , Mediadores da Inflamação/metabolismo , Masculino , MicroRNAs/sangue , Ratos Sprague-Dawley , Distribuição Tecidual
17.
Pulm Circ ; 8(1): 2045893217750613, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29251557

RESUMO

Reversing pathologic alterations in vascular microRNA (miRNA) expression represents a potential therapeutic strategy for pulmonary hypertension. While polyethylenimine (PEI) has previously been shown to be an effective vehicle for vascular lung-directed delivery of plasmid DNA, it remains unclear whether this utility is generalizable to miRNAs. Here we show that despite elevated lung levels, the intravenous infusion of PEI-miRNA mimic complexes fails to provide lung-selective delivery in rats.

18.
Am J Hypertens ; 31(10): 1093-1097, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-29800045

RESUMO

BACKGROUND: Women who have had preeclampsia (PE) are at increased risk for premature cardiovascular disease (CVD). The underlying pathophysiology of this risk remains unclear, but potentially involves subclinical vascular damage or dysfunction. Alterations in the levels of circulating microRNAs may be implicated, as they are known to play pervasive roles in vascular biology. We investigated whether levels of circulating microRNAs are altered between women with premature acute coronary syndrome (ACS), with and without a history of PE. METHODS: Women with premature ACS (age ≤ 55 years) were categorized based on a prior history of PE or normotensive pregnancy. Relative plasma levels of 372 microRNAs were initially assessed by polymerase chain reaction array in a subset of subjects (n = 12-13/group) matched for age, chronic hypertension, dyslipidemia, and smoking status. Candidate microRNAs were then validated in a larger cohort of ACS patients (n = 176). RESULTS: MicroRNAs previously linked to angiogenesis (miR-126-3p), inflammation (miR-146a-5p), and cholesterol metabolism (miR-122-5p) were significantly decreased in women with prior PE compared to women with prior normotensive pregnancy (P = 0.002, 0.017, and 0.009, respectively), even after adjustment for chronic hypertension. CONCLUSIONS: Circulating levels of miR-126-3p, -146a-5p, and -122-5p were significantly decreased in women with premature ACS who reported prior PE compared to those with prior normotensive pregnancy. These data provide novel insight into potential pathways that may contribute to the increased risk of CVD following PE.


Assuntos
Síndrome Coronariana Aguda/genética , MicroRNA Circulante/sangue , Pré-Eclâmpsia/genética , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/fisiopatologia , Adulto , Idade de Início , Canadá/epidemiologia , Estudos de Casos e Controles , Regulação para Baixo , Feminino , Marcadores Genéticos , Humanos , MicroRNAs/sangue , Pessoa de Meia-Idade , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Fatores de Risco , Suíça/epidemiologia , Estados Unidos/epidemiologia
19.
Can J Cardiol ; 33(12): 1683-1692, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29173607

RESUMO

BACKGROUND: Women with previous cardiometabolic complications of pregnancy experience double the risk of cardiovascular disease. However, few data exist on the clinical effect of these complications at the time of an acute coronary syndrome (ACS). The objective of this work was to compare risk factors, clinical features, and outcomes among women with premature ACS with or without previous pregnancy complications (gestational diabetes and/or hypertensive disorders of pregnancy). METHODS: Data were obtained from a multicentre cohort of individuals hospitalized with premature ACS. A total of 251 parous women were included and provided obstetric history and blood samples. They were followed for the development of major adverse cardiac events at 12 months. RESULTS: At presentation with ACS, women with a previous pregnancy complication (38%) were slightly younger than were women without such complications (47.4 ± 6.2 vs 49.1 ± 5.6 years; P = 0.002). They also had more traditional atherosclerotic risk factors. Specifically, women with previous preeclampsia were more likely to have chronic hypertension and an elevated ratio of soluble fms-like tyrosine kinase:placental growth factor. There was no between-group difference in Global Registry of Acute Coronary Events (GRACE) score or troponin tertile but there was a trend toward higher risk of ST-elevation myocardial infarction in women who had a previous pregnancy complication (odds ratio, 1.80; 95% confidence interval, 1.00-3.23; P = 0.05). There was also an increased risk of recurrent ACS at 12 months in women with previous preeclampsia (hazard ratio, 6.79; 95% confidence interval, 1.37-33.63; P = 0.02). CONCLUSIONS: Among a cohort of women with ACS, previous pregnancy complications were associated with more severe disease and poorer outcome.


Assuntos
Síndrome Coronariana Aguda/etiologia , Complicações na Gravidez , Sistema de Registros , Medição de Risco , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Canadá/epidemiologia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida/tendências
20.
Pulm Circ ; 7(2): 476-485, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28597756

RESUMO

Translational research depends on the relevance of animal models and how well they replicate human disease. Here, we investigated plasma levels of three important pro-inflammatory cytokines (TNFα, IL-6, and MCP-1), known to be elevated in human pulmonary arterial hypertension (PAH), and systematically assessed their levels in PAH patients compared to five different rodent models of pulmonary hypertension (PH). A consistent immunoassay platform (Luminex xMAP) and source (Millipore) was used to measure all specimens. PAH patients (n = 29) exhibited significant elevations in all three cytokines (median [IQR] pg/mL; TNFα, 7.0 [4.8-11.7]; IL-6, 9.2 [3.8-17.2]; MCP-1, 109 [65-142]) versus healthy participants (n = 20) (median [IQR] pg/mL; TNFα, 3.0 [2.0-3.6]; IL-6, 1.7 [0.5-7.2]; MCP-1, 79 [49-93]. In contrast, mice with PH established after three weeks of hypoxia (n = 18) or SU5416 plus hypoxia (n = 20) showed no significant change in their plasma cytokine levels versus controls (n = 16), based on three to four independent experiments per group. Similarly, plasma cytokine levels were not elevated in rats with PH established three weeks after monocrotaline (n = 23), eight weeks after SU5416 alone (n = 10) or six to eight weeks after SU5416 plus hypoxia (n = 21) versus controls (n = 36 rats), based on three to eight independent experiments per group. Positive biologic control specimens from sepsis patients (n = 9), cecal-ligation and puncture (CLP)-induced septic mice (n = 6), and lipopolysaccharide-induced septic rats (n = 4) showed robust elevations in all three cytokines. This study suggests that animal models commonly used for the development of novel diagnostic and therapeutic approaches for PAH may have limited construct validity with respect to markers of systemic immune activation seen in human patients.

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