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1.
Am Heart J ; 263: 1-14, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37116604

RESUMO

BACKGROUND: Electronic health record (EHR)-based identification of heart failure with preserved ejection fraction (HFpEF) in the clinical setting may facilitate screening for clinical trials by improving the understanding of its epidemiology and outcomes; yet, previous data have yielded variable results. We sought to characterize groups identified with HFpEF by different EHR screening strategies and their associated long-term outcomes across a large and diverse population. METHODS: We retrospectively analyzed 116,499 consecutive patients from an academic referral center who underwent echocardiography, and 9,263 patients who underwent echocardiography within 6 months of right heart catheterization (RHC), between 2008 and 2018. EHR-based screening strategies identified patients with HFpEF using 1) International Classification of Diseases (ICD)-9/10 codes, 2) H2FpEF score ≥6 and ejection fraction (EF) ≥50%, or 3) RHC wedge pressure ≥15 mmHg and EF ≥50%, when available. Primary outcomes were 1) cumulative incident heart failure hospitalization (HFH), and 2) death, over 10 years. RESULTS: There were 33,461 (29%) patients who met either ICD or H2FpEF-HFpEF definition, of whom 5,310 (16%) met both criteria. Compared to ICD-HFpEF, patients with H2FpEF-HFpEF were more likely older (median age 72 vs 67), White (78% vs 64%), and had atrial fibrillation (97% vs 41%). Among those also with RHC, 6,353 (69%) patients met any HFpEF criteria, of whom only 783 (12%) satisfied all three criteria. Female sex was more common among RHC-HFpEF (55%) compared to other methods (H2FpEF-HFpEF, 47%; ICD-HFpEF, 43%). Atrial fibrillation was substantially higher among HFpEF identified by the H2FpEF score (97%) compared to other methods (49% for ICD and 47% for RHC). Across HFpEF screening methods, 10-year cumulative incidence rates for HFH was 32% to 45% for echocardiography only and 43% to 52% for echocardiography and RHC populations; 10-year risk of death was 54% to 56% for echocardiography only and 52% to 57% for echocardiography and RHC populations. CONCLUSIONS: Different EHR-based HFpEF definitions identified cohorts with modest overlap and varying baseline characteristics. Yet, long-term risk for HFH and death were similarly high for cohorts identified among both populations undergoing echocardiography only or echocardiography and RHC. These data aid in identifying relevant subgroups in clinical trials of HFpEF.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Feminino , Idoso , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Registros Eletrônicos de Saúde , Estudos Retrospectivos , Prognóstico
2.
EMBO J ; 30(20): 4142-56, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21847094

RESUMO

Histone deacetylases (HDACs) deacetylate histones and non-histone proteins, thereby affecting protein activity and gene expression. The regulation and function of the cytoplasmic class IIb HDAC6 in endothelial cells (ECs) is largely unexplored. Here, we demonstrate that HDAC6 is upregulated by hypoxia and is essential for angiogenesis. Silencing of HDAC6 in ECs decreases sprouting and migration in vitro and formation of functional vascular networks in matrigel plugs in vivo. HDAC6 regulates zebrafish vessel formation, and HDAC6-deficient mice showed a reduced formation of perfused vessels in matrigel plugs. Consistently, overexpression of wild-type HDAC6 increases sprouting from spheroids. HDAC6 function requires the catalytic activity but is independent of ubiquitin binding and deacetylation of α-tubulin. Instead, we found that HDAC6 interacts with and deacetylates the actin-remodelling protein cortactin in ECs, which is essential for zebrafish vessel formation and which mediates the angiogenic effect of HDAC6. In summary, we show that HDAC6 is necessary for angiogenesis in vivo and in vitro, involving the interaction and deacetylation of cortactin that regulates EC migration and sprouting.


Assuntos
Movimento Celular , Cortactina/metabolismo , Histona Desacetilases/metabolismo , Neovascularização Fisiológica , Tubulina (Proteína)/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Acetilação , Animais , Carcinoma Pulmonar de Lewis/enzimologia , Células Cultivadas , Células Endoteliais/metabolismo , Feminino , Desacetilase 6 de Histona , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Knockout
3.
Arterioscler Thromb Vasc Biol ; 33(3): 533-43, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23288173

RESUMO

OBJECTIVE: Histone deacetylases (HDACs) modulate gene expression by deacetylation of histone and nonhistone proteins. Several HDACs control angiogenesis, but the role of HDAC9 is unclear. METHODS AND RESULTS: Here, we analyzed the function of HDAC9 in angiogenesis and its involvement in regulating microRNAs. In vitro, silencing of HDAC9 reduces endothelial cell tube formation and sprouting. Furthermore, HDAC9 silencing decreases vessel formation in a spheroid-based Matrigel plug assay in mice and disturbs vascular patterning in zebrafish embryos. Genetic deletion of HDAC9 reduces retinal vessel outgrowth and impairs blood flow recovery after hindlimb ischemia. Consistently, overexpression of HDAC9 increases endothelial cell sprouting, whereas mutant constructs lacking the catalytic domain, the nuclear localization sequence, or sumoylation site show no effect. To determine the mechanism underlying the proangiogenic effect of HDAC9, we measured the expression of the microRNA (miR)-17-92 cluster, which is known for its antiangiogenic activity. We demonstrate that silencing of HDAC9 in endothelial cells increases the expression of miR-17-92. Inhibition of miR-17-20a rescues the sprouting defects induced by HDAC9 silencing in vitro and blocking miR-17 expression partially reverses the disturbed vascular patterning of HDAC9 knockdown in zebrafish embryos. CONCLUSIONS: We found that HDAC9 promotes angiogenesis and transcriptionally represses the miR-17-92 cluster.


Assuntos
Histona Desacetilases/metabolismo , Células Endoteliais da Veia Umbilical Humana/enzimologia , Isquemia/enzimologia , MicroRNAs/metabolismo , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Proteínas Repressoras/metabolismo , Neovascularização Retiniana/enzimologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Células HEK293 , Membro Posterior , Histona Desacetilases/deficiência , Histona Desacetilases/genética , Humanos , Isquemia/genética , Isquemia/fisiopatologia , Camundongos , Camundongos Knockout , MicroRNAs/genética , Mutação , Neovascularização Fisiológica/genética , Interferência de RNA , RNA Longo não Codificante , Fluxo Sanguíneo Regional , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Neovascularização Retiniana/genética , Neovascularização Retiniana/fisiopatologia , Transfecção , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
4.
J Mol Cell Cardiol ; 50(2): 333-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21147123

RESUMO

Early pro-angiogenic cells (EPCs) have been shown to be involved in neovascularization, angiogenesis and re-endothelialization and cathepsin L inhibition blunted their pro-angiogenic effect. In the present study, we have analysed and mapped the proteome and secretome of human EPCs, utilizing a combination of difference in-gel electrophoresis (DIGE) and shotgun proteomics. A population of 206 protein spots were analysed, with 171 being identified in the cellular proteome of EPCs. 82 proteins were identified in their conditioned medium, including the alternative macrophage markers C-C motif chemokine 18 (CCL18) and the hemoglobin scavenger receptor CD163 as well as platelet factor 4 (CXCL4) and platelet basic protein (CXCL7) with "platelet alpha granule" being returned as the top category according to the Gene Ontology Annotation. Apart from cathepsin L, the cathepsin L inhibitor also attenuated the release of a wide range of other cathepsins and lysosomal proteins such as legumain, but stimulated the secretion of members of the S100 protein family. The data presented here are the most comprehensive characterization of protein expression and secretion in human EPCs to date and highlight the potential importance of cysteine proteases in the processing of platelet factors for their pro-angiogenic potential. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".


Assuntos
Células Endoteliais/metabolismo , Proteômica , Plaquetas/citologia , Catepsina L/antagonistas & inibidores , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Mioblastos de Músculo Liso/efeitos dos fármacos , Mioblastos de Músculo Liso/metabolismo
5.
J Exp Med ; 201(11): 1825-35, 2005 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-15928198

RESUMO

The regulation of acetylation is central for the epigenetic control of lineage-specific gene expression and determines cell fate decisions. We provide evidence that the inhibition of histone deacetylases (HDACs) blocks the endothelial differentiation of adult progenitor cells. To define the mechanisms by which HDAC inhibition prevents endothelial differentiation, we determined the expression of homeobox transcription factors and demonstrated that HoxA9 expression is down-regulated by HDAC inhibitors. The causal involvement of HoxA9 in the endothelial differentiation of adult progenitor cells is supported by the finding that HoxA9 overexpression partially rescued the endothelial differentiation blockade induced by HDAC inhibitors. Knockdown and overexpression studies revealed that HoxA9 acts as a master switch to regulate the expression of prototypical endothelial-committed genes such as endothelial nitric oxide synthase, VEGF-R2, and VE-cadherin, and mediates the shear stress-induced maturation of endothelial cells. Consistently, HoxA9-deficient mice exhibited lower numbers of endothelial progenitor cells and showed an impaired postnatal neovascularization capacity after the induction of ischemia. Thus, HoxA9 is regulated by HDACs and is critical for postnatal neovascularization.


Assuntos
Diferenciação Celular/fisiologia , Células Endoteliais/fisiologia , Regulação da Expressão Gênica/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Histona Desacetilases/metabolismo , Proteínas de Homeodomínio/biossíntese , Animais , Antígenos CD , Caderinas/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Sangue Fetal/citologia , Sangue Fetal/fisiologia , Células-Tronco Hematopoéticas/citologia , Proteínas de Homeodomínio/genética , Humanos , Isquemia/metabolismo , Camundongos , Camundongos Knockout , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Estresse Mecânico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
Blood ; 113(22): 5669-79, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19351956

RESUMO

Class IIa histone deacetylases (HDACs) are signal-responsive regulators of gene expression involved in vascular homeostasis. To investigate the differential role of class IIa HDACs for the regulation of angiogenesis, we used siRNA to specifically suppress the individual HDAC isoenzymes. Silencing of HDAC5 exhibited a unique pro-angiogenic effect evidenced by increased endothelial cell migration, sprouting, and tube formation. Consistently, overexpression of HDAC5 decreased sprout formation, indicating that HDAC5 is a negative regulator of angiogenesis. The antiangiogenic activity of HDAC5 was independent of myocyte enhancer factor-2 binding and its deacetylase activity but required a nuclear localization indicating that HDAC5 might affect the transcriptional regulation of gene expression. To identify putative HDAC5 targets, we performed microarray expression analysis. Silencing of HDAC5 increased the expression of fibroblast growth factor 2 (FGF2) and angiogenic guidance factors, including Slit2. Antagonization of FGF2 or Slit2 reduced sprout induction in response to HDAC5 siRNA. Chromatin immunoprecipitation assays demonstrate that HDAC5 binds to the promoter of FGF2 and Slit2. In summary, HDAC5 represses angiogenic genes, such as FGF2 and Slit2, which causally contribute to capillary-like sprouting of endothelial cells. The derepression of angiogenic genes by HDAC5 inactivation may provide a useful therapeutic target for induction of angiogenesis.


Assuntos
Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Histona Desacetilases/fisiologia , Neovascularização Fisiológica/genética , Inibidores da Angiogênese/antagonistas & inibidores , Inibidores da Angiogênese/fisiologia , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases , Histona Desacetilases/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/fisiologia , Modelos Biológicos , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno/farmacologia , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/fisiologia
7.
Arterioscler Thromb Vasc Biol ; 29(4): 571-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19122169

RESUMO

OBJECTIVE: Endothelial progenitor cells (EPCs) comprise a heterogeneous population of cells, which improve therapeutic neovascularization after ischemia. The neovascularization-promoting potential of progenitor cells depends on survival and retention of the infused cells to the tissue. Caspases mediate apoptosis but are also involved in other critical biological processes. Therefore, we aimed to address the role of caspases in proangiogenic cells. METHODS AND RESULTS: The caspase-8 inhibitor zIETD abrogated the ex vivo formation of EPCs, inhibited EPC adhesion and migration, and reduced their capacity to improve neovascularization in vivo. Consistently, cells isolated from caspase-8-deficient mice exhibited a reduced capacity for enhancing neovascularization when transplanted into mice after hindlimb ischemia. Because inhibition of Caspase-8 reduced the adhesion and homing functions of EPCs, we further determined the surface expression of integrins and receptors involved in cell recruitment to ischemic tissues. Pharmacological inhibition of caspase-8 and genetic depletion of caspase-8 reduced the expression of the fibronectin receptor subunits alpha5 and beta1 and the SDF-1 receptor CXCR4. Moreover, we identified the E3 ubiquitin ligase Cbl-b, which negatively regulates integrin and receptor-mediated signaling, as a potential Caspase-8 substrate. CONCLUSIONS: In summary, our data demonstrate a novel apoptosis-unrelated role of caspase-8 in proangiogenic cells.


Assuntos
Caspase 8/metabolismo , Células Endoteliais/enzimologia , Isquemia/enzimologia , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Células-Tronco/enzimologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Síndrome de Alstrom , Animais , Caspase 8/genética , Inibidores de Caspase , Adesão Celular , Movimento Celular , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/transplante , Membro Posterior , Humanos , Integrina alfaV/metabolismo , Integrina beta1/metabolismo , Isquemia/fisiopatologia , Isquemia/cirurgia , Camundongos , Camundongos Knockout , Camundongos Nus , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos/farmacologia , Proteínas Proto-Oncogênicas c-cbl/metabolismo , RNA Mensageiro/metabolismo , Receptores CXCR4/metabolismo , Receptores de Fibronectina/metabolismo , Transplante de Células-Tronco , Células-Tronco/efeitos dos fármacos
8.
J Mol Cell Cardiol ; 45(3): 429-36, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18619973

RESUMO

Endothelial progenitor cells (EPC) significantly contribute to neovascularization and endothelial regeneration. Risk factors for coronary artery disease, particularly diabetes mellitus, reduce the number and functional activity of EPC. As we have recently shown, expression and activity of the matrix degrading cysteine protease cathepsin L in EPC is required for tissue invasion and EPC-mediated improvement of neovascularization. Therefore, we investigated the effect of high glucose and diabetes mellitus on EPC invasion and cathepsin L activity. Incubation of EPC with high levels of glucose (10-30 mM) dose-dependently decreased cathepsin L activity (glucose 20 mM: 67+/-4% compared to control; p<0.05) and protein expression (48+/-5% of control, p<0.05). In contrast, other proteases of the cathepsin family such as cathepsins D and O, and the matrix metalloproteinases MMP-2 and MMP-9 were not altered with high glucose. Cathepsin L mRNA was not affected suggesting that a posttranscriptional mechanism is responsible for cathepsin L down-regulation. As a functional consequence, high glucose significantly reduced the gelatinolytic activity and invasion of EPC (50+/-5% of control). Importantly, EPC of patients with type 2 diabetes revealed profoundly decreased cathepsin L expression and activity as compared to EPC derived from healthy controls. Taken together, high glucose significantly reduces the protein expression and activity of cathepsin L, which is involved in matrix degradation and required for invasion of EPC into the ischemic tissue, and, thereby, may limit the functional capacity of EPC to improve neovascularization in diabetics.


Assuntos
Catepsinas/antagonistas & inibidores , Movimento Celular/fisiologia , Endotélio Vascular/metabolismo , Glucose/efeitos adversos , Glucose/fisiologia , Células-Tronco/metabolismo , Adulto , Idoso , Catepsina L , Catepsinas/biossíntese , Catepsinas/metabolismo , Catepsinas/fisiologia , Células Cultivadas , Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/fisiologia , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/patologia , Endotélio Vascular/enzimologia , Endotélio Vascular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/enzimologia , Neovascularização Patológica/patologia , Células-Tronco/enzimologia , Células-Tronco/patologia
9.
Circulation ; 111(22): 2981-7, 2005 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15927972

RESUMO

BACKGROUND: The maintenance of endothelial integrity plays a critical role in preventing atherosclerotic disease progression. Endothelial progenitor cells (EPCs) were experimentally shown to incorporate into sites of neovascularization and home to sites of endothelial denudation. Circulating EPCs may thus provide an endogenous repair mechanism to counteract ongoing risk factor-induced endothelial injury and to replace dysfunctional endothelium. METHODS AND RESULTS: In 120 individuals (43 control subjects, 44 patients with stable coronary artery disease, and 33 patients with acute coronary syndromes), circulating EPCs were defined by the surface markers CD34+KDR+ and analyzed by flow cytometry. Cardiovascular events (cardiovascular death, unstable angina, myocardial infarction, PTCA, CABG, or ischemic stroke) served as outcome variables over a median follow-up period of 10 months. Patients suffering from cardiovascular events had significantly lower numbers of EPCs (P<0.05). Reduced numbers of EPCs were associated with a significantly higher incidence of cardiovascular events by Kaplan-Meier analysis (P=0.0009). By multivariate analysis, reduced EPC levels were a significant, independent predictor of poor prognosis, even after adjustment for traditional cardiovascular risk factors and disease activity (hazard ratio, 3.9; P<0.05). CONCLUSIONS: Reduced levels of circulating EPCs independently predict atherosclerotic disease progression, thus supporting an important role for endogenous vascular repair to modulate the clinical course of coronary artery disease.


Assuntos
Vasos Sanguíneos/fisiologia , Doenças Cardiovasculares/diagnóstico , Células Endoteliais/citologia , Valor Preditivo dos Testes , Regeneração , Células-Tronco/citologia , Adulto , Idoso , Angina Pectoris/sangue , Antígenos CD34/análise , Aterosclerose/etiologia , Contagem de Células Sanguíneas , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
10.
Circulation ; 111(9): 1184-91, 2005 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-15753227

RESUMO

BACKGROUND: Transplantation of endothelial progenitor cells (EPCs) improves neovascularization after ischemia, but patients with coronary artery disease (CAD) or diabetes mellitus show a reduced number of EPCs and impaired functional activity. Therefore, we investigated the effects of risk factors, such as glucose and TNF-alpha, on the number of EPCs in vitro to elucidate the underlying mechanisms. METHODS AND RESULTS: EPCs of patients or healthy subjects were isolated from peripheral blood. Incubation with glucose or TNF-alpha dose-dependently reduced the number of EPCs (79.9+/-1.3% and 74.3+/-8.1% of control; P<0.05, respectively). This reduction was not caused by apoptosis. TNF-alpha and glucose induced a dose- and time-dependent activation of the p38 MAP kinase, the downstream kinase mitogen- and stress-activated kinase 1, and the transcription factor cAMP-responsive element-binding protein (CREB), in EPCs. Moreover, EPCs from CAD patients had significantly higher basal p38-phosphorylation levels (1.83+/-0.2-fold increase; P<0.05) compared with healthy subjects. The inhibition of the p38-kinase by SB203580 or infection with a dominant negative p38 kinase adenovirus significantly increased basal number of EPCs (136.7+/-6.3% and 142.9+/-18% versus control, respectively). Likewise, ex vivo cultivation of EPCs from patients with CAD with SB203580 significantly increased the number of EPCs and partially reversed the impaired capacity for neovascularization of EPCs in vivo (relative blood flow: 0.40+/-0.03 versus 0.64+/-0.08, P<0.05). The increased numbers of EPCs by SB203580 were associated with an augmentation of EPC proliferation and a reduction of cells expressing the monocytic marker proteins CD14 and CD64, suggesting that p38 regulates proliferation and differentiation events. CONCLUSIONS: These results demonstrate that p38 MAP kinase plays a pivotal role in the signal transduction pathways regulating the number of EPCs ex vivo. SB203580 can prevent the negative effects of TNF-alpha and glucose on the number of EPCs and may be useful to improve the number of EPCs for potential cell therapy.


Assuntos
Doença das Coronárias/enzimologia , Células-Tronco/enzimologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Fator 2 Ativador da Transcrição , Adulto , Idoso , Sequência de Aminoácidos , Animais , Apoptose , Contagem de Células , Diferenciação Celular , Divisão Celular/efeitos dos fármacos , Células Cultivadas/citologia , Células Cultivadas/efeitos dos fármacos , Comorbidade , Doença das Coronárias/epidemiologia , Doença das Coronárias/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Glucose/farmacologia , Membro Posterior/irrigação sanguínea , Humanos , Imidazóis/farmacologia , Isquemia/enzimologia , Isquemia/patologia , Isoquinolinas/farmacologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Piridinas/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Transplante de Células-Tronco , Células-Tronco/citologia , Sulfonamidas/farmacologia , Fatores de Transcrição/metabolismo , Transplante Heterólogo , Fator de Necrose Tumoral alfa/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
11.
Novartis Found Symp ; 274: 214-23; discussion 223-7, 272-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17019814

RESUMO

The biological limitations to cardiac regenerative growth create a clinical need to promote more efficient cardiac repair. Experimental studies and early-phase clinical trials indicate that progenitor cells may be useful as a therapeutic tool to improve heart function after myocardial ischaemia. This paper will summarize experimental studies to determine (1) the mechanisms underlying progenitor cell homing to ischaemic tissue and (2) to define transcription factors involved in endothelial maturation of progenitor cells. Homing seems to be assisted by a proteolytic enzyme, cathepsin L, which degrades the extracellular matrix. In an in vitro assay, a cathepsin inhibitor prevented different progenitor cell populations from passing through a matrigel layer. In vivo, progenitor cells lacking cathepsin L had an impaired capacity to promote neovascularization in ischaemic mouse limbs compared with normal, wild-type cells. Differentiation of progenitor cells towards the endothelial phenotype involves a member of the homeobox gene family, HoxA9. HoxA9 regulates endothelial gene expression (eNOS, KDR, VE-cadherin). Moreover, HoxA9-deficient mice have a severe impairment of neovascularization capacity after ischaemia. In the second part of the paper, we describe clinical studies using bone marrow or the peripheral blood-derived cells for functional recovery of patients with acute and chronic heart failure (TOPCARE-AMI, TOPCARE-CHF). Whereas blood-derived and bone marrow-derived progenitor cells were equally effective in patients with acute myocardial infarction, bone marrow-derived cells were significantly better than blood-derived progenitor cells in patients with chronic ischaemic heart disease.


Assuntos
Miocárdio/patologia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular , Linhagem da Célula , Ensaios Clínicos como Assunto , Humanos , Isquemia/patologia , Camundongos , Modelos Biológicos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Isquemia Miocárdica/patologia , Miocárdio/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
12.
Circ Res ; 91(9): 837-44, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12411399

RESUMO

The histone deacetylase (HDAC) inhibitor trichostatin A (TSA) inhibits hypoxia-stimulated angiogenesis. Endothelial nitric oxide synthase (eNOS)-derived NO is central to angiogenesis signaling in endothelial cells (ECs). We hypothesized that the HDAC-dependent regulation of angiogenesis may involve a modulatory effect on eNOS expression. The HDAC inhibitors TSA, butyric acid (BuA), and MS-275 time- and concentration-dependently suppressed eNOS protein levels to 41+/-2%, 46+/-12%, and 40+/-12% of control, respectively. In parallel, TSA and BuA also downregulated eNOS mRNA expression to 21+/-4% and 37+/-4% of control. TSA also attenuated the NO-dependent relaxation of porcine coronary arteries (P<0.0001, TSA 1 micromol/L) and prevented tube formation in a human angiogenesis assay. Although vascular endothelial growth factor substitution did not compensate for the inhibitory effect of TSA, exogenous NO reversed the inhibition of angiogenesis by TSA. To address the underlying signaling mechanism, we characterized the effect of TSA on eNOS gene transcription and mRNA half-life. Although TSA decreased both eNOS protein and mRNA levels, TSA paradoxically enhanced the activity of the eNOS promoter, and did not alter the eNOS transcription rate in nuclear run-on experiments, suggesting that TSA posttranscriptionally targets eNOS mRNA. These data indicate that HDAC-dependent mechanisms contribute to the regulation of eNOS expression in ECs.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Vasodilatação/efeitos dos fármacos , Animais , Linhagem Celular , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Fatores de Ligação de DNA Eritroide Específicos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Genes Reporter , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Linfocinas/farmacologia , Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo III , Oligonucleotídeos Antissenso/farmacologia , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Suínos , Fatores de Transcrição/genética , Transfecção , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
13.
Circ Res ; 94(5): 686-92, 2004 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-14752032

RESUMO

p21(Cip1) (p21) controls cell cycle progression and apoptosis in mature endothelial cells (ECs) and regulates size and cycling of the hematopoietic progenitor cell pool. Because circulating endothelial progenitor cells (EPCs) contribute to postnatal neovascularization in addition to mature ECs, we investigated the regulation of ECs and EPCs in p21-deficient mice. Mature aortic EC proliferation was increased in homozygous p21(-/-) and heterozygous p21(+/-) mice, in which p21 protein levels are reduced to one third of wild-type (WT). In contrast, apoptosis sensitivity was increased by 3.5-fold only in p21(-/-), but not in p21(+/-) mice. Consistently, in vivo apoptosis of ECs within areas of neovascularization was elevated in p21(-/-) but not in p21(+/-) mice. EPC numbers were elevated 2-fold in p21(-/-) mice compared with WT (P<0.001), and clonal expansion capacity of EPCs was increased from 25+/-4 (WT) to 57+/-8 colony-forming units in p21(-/-) mice (P<0.005). EPC numbers and expansion were likewise increased in p21(+/-) mice. As the integrative endpoint, in vivo neovascularization reflecting all p21-affected parameters was increased over WT only in p21(+/-) (P<0.001), but not in p21(-/-) mice. In conclusion, reduced p21 protein levels of mice lacking one p21 allele are associated with increased proliferation of ECs and EPCs, whereas survival of ECs to apoptotic stimuli in vitro and in vivo is not impaired. Under these conditions, neovascularization was increased. In contrast, complete p21 deficiency did not result in an increased neovascularization despite increased mature EC and EPC proliferation. This may be due to the sensitization of ECs against apoptosis.


Assuntos
Circulação Colateral/fisiologia , Ciclinas/fisiologia , Células Endoteliais/citologia , Endotélio Vascular/citologia , Células-Tronco Mesenquimais/citologia , Alelos , Animais , Aorta/citologia , Apoptose/fisiologia , Divisão Celular , Células Cultivadas/metabolismo , Ensaio de Unidades Formadoras de Colônias , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/sangue , Ciclinas/deficiência , Ciclinas/genética , Células Endoteliais/metabolismo , Feminino , Genótipo , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Próteses e Implantes , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes de Fusão/fisiologia , Baço/citologia , Transfecção , Veias Umbilicais/citologia
14.
Circ Res ; 92(9): 1049-55, 2003 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-12676819

RESUMO

Endothelial progenitor cells (EPCs) play an important role in postnatal neovascularization of ischemic tissue. Ex vivo expansion of EPCs might be useful for potential clinical cell therapy of myocardial ischemia. However, cultivation of primary cells leads to cellular aging (senescence), thereby severely limiting the proliferative capacity. Therefore, we investigated whether statins might be able to prevent senescence of EPCs. EPCs were isolated from peripheral blood and characterized. After ex vivo cultivation, EPCs became senescent as determined by acidic beta-galactosidase staining. Atorvastatin or mevastatin dose-dependently inhibited the onset of EPC senescence in culture. Moreover, atorvastatin increased proliferation of EPCs as assessed by BrdU incorporation and colony-forming capacity. Whereas geranylgeranylpyrophosphate or farnesylpyrophosphate reduced the senescence inhibitory effect of atorvastatin, NO synthase inhibition, antioxidants, or Rho kinase inhibitors had no effect. To get further insights into the underlying downstream effects of statins, we measured telomerase activity and determined the expression of various cell cycle regulatory genes by using a microarray assay. Whereas telomerase activity did not change, atorvastatin modulated expression of cell cycle genes including upregulation of cyclins and downregulation of the cell cycle inhibitor p27Kip1. Taken together, statins inhibited senescence of EPCs independent of NO, reactive oxygen species, and Rho kinase, but dependent on geranylgeranylpyrophosphate. Atorvastatin-mediated prevention of EPC senescence appears to be mediated by the regulation of various cell cycle proteins. The inhibition of EPC senescence and induction of EPC proliferation by statins in vitro may importantly improve the functional activity of EPCs for potential cell therapy.


Assuntos
Endotélio Vascular/citologia , Genes cdc , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lovastatina/análogos & derivados , Lovastatina/farmacologia , Pirróis/farmacologia , Células-Tronco/efeitos dos fármacos , Atorvastatina , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/biossíntese , Ciclinas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/fisiologia , Telomerase/metabolismo , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
17.
Atherosclerosis ; 211(1): 249-54, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20211468

RESUMO

BACKGROUND: In patients with coronary artery disease (CAD), higher numbers of circulating endothelial progenitor cells (EPC) favourably influence clinical outcome. Controversially, increased apoptosis of endothelial cells (EC) may reflect vascular damage. Statins have been shown to improve vascular damage and enhance EPC function and numbers. The availability of ezetimibe, a potent novel cholesterol absorption inhibitor, allows to distinguish between lipid-lowering and pleiotropic properties of statins. METHODS AND FINDINGS: 43 patients with CAD were assigned to receive either: de novo atorvastatin (group A; n=17), ezetimibe as add-on to chronic statin therapy (group B; n=14), or dose escalation of atorvastatin (group C; n=12) over 4 weeks. Circulating apoptotic EC (CD45-CD146+vWF+Annexin-V+) and EPC (CD34+KDR+) were quantified using flow cytometry. LDL cholesterol levels were significantly reduced in all treatment arms. Both statin groups, group A and group C, showed significantly reduced circulating apoptotic EC by 50% each (p<0.01). On the other hand, there was a significant doubling in the numbers of circulating EPC in group A and group C (p<0.005, each). Consequently, the endothelial damage-index calculated from numbers of circulating apoptotic mature EC related to EPC numbers, was improved in group A by 79% (p<0.01) and in group C by 70% (p<0.05). In contrast, sole LDL reduction by ezetimibe exerted no effect on any of the different circulating endothelial cell types. CONCLUSION: Thus, the improvement in numbers of EPC and reduction of mature apoptotic EC after 4 weeks of statin therapy, document a novel pleiotropic effect of statin therapy in patients with CAD.


Assuntos
Anticolesterolemiantes/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Adulto , Idoso , Apoptose/efeitos dos fármacos , Azetidinas/uso terapêutico , Células Endoteliais/fisiologia , Ezetimiba , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Regeneração/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos
18.
Blood ; 109(4): 1472-8, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17047146

RESUMO

Posttranslational histone modification by acetylation or methylation regulates gene expression. Here, we investigated the role of the histone lysine methyltransferase MLL for angiogenic functions in human umbilical vein endothelial cells. Suppression of MLL expression by siRNA or incubation with the pharmacologic methyltransferase inhibitor 5'-deoxy-5'-(methylthio)adenosine significantly decreased endothelial-cell migration and capillary sprout formation, indicating that methyltransferase activity is required for proangiogenic endothelial-cell functions. Because the expression of homeodomain transcription factors (Hox) is regulated by MLL, we elucidated the role of Hox gene expression. MLL silencing was associated with reduced mRNA and protein expression of HoxA9 and HoxD3, whereas HoxB3, HoxB4, HoxB5, and HoxB9 were not altered. Overexpression of HoxA9 or HoxD3 partially compensated for impaired migration in MLL siRNA-transfected endothelial cells, suggesting that HoxA9 and HoxD3 both contribute to MLL-dependent migration. As a potential underlying mechanism, MLL siRNA down-regulated mRNA and protein levels of the HoxA9-dependent axon guidance factor EphB4. In contrast, MLL knockdown effects on capillary sprouting were not rescued by HoxA9 or HoxD3 overexpression, indicating that MLL affects additional targets required for 3-dimensional sprout formation. We conclude that MLL regulates endothelial-cell migration via HoxA9 and EphB4, whereas sprout formation requires MLL-dependent signals beyond HoxA9 and HoxD3.


Assuntos
Endotélio Vascular/citologia , Proteína de Leucina Linfoide-Mieloide/fisiologia , Neovascularização Fisiológica , Movimento Celular , Células Endoteliais/citologia , Regulação da Expressão Gênica/fisiologia , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/fisiologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Humanos , Proteínas Metiltransferases , Processamento de Proteína Pós-Traducional
19.
Genes Dev ; 21(20): 2644-58, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17938244

RESUMO

The nicotinamide adenine dinucleotide (NAD(+))-dependent histone deacetylase Sir2 regulates life-span in various species. Mammalian homologs of Sir2 are called sirtuins (SIRT1-SIRT7). In an effort to define the role of sirtuins in vascular homeostasis, we found that among the SIRT family, SIRT1 uniquely regulates angiogenesis signaling. We show that SIRT1 is highly expressed in the vasculature during blood vessel growth, where it controls the angiogenic activity of endothelial cells. Loss of SIRT1 function blocks sprouting angiogenesis and branching morphogenesis of endothelial cells with consequent down-regulation of genes involved in blood vessel development and vascular remodeling. Disruption of SIRT1 gene expression in zebrafish and mice results in defective blood vessel formation and blunts ischemia-induced neovascularization. Through gain- and loss-of-function approaches, we show that SIRT1 associates with and deacetylates the forkhead transcription factor Foxo1, an essential negative regulator of blood vessel development to restrain its anti-angiogenic activity. These findings uncover a novel and unexpected role for SIRT1 as a critical modulator of endothelial gene expression governing postnatal vascular growth.


Assuntos
Sirtuínas/fisiologia , Animais , Vasos Sanguíneos/crescimento & desenvolvimento , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Morfogênese , Neovascularização Fisiológica/genética , Interferência de RNA , Sirtuína 1 , Sirtuínas/deficiência , Sirtuínas/genética , Peixe-Zebra
20.
Eur Heart J ; 27(10): 1182-90, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16621868

RESUMO

AIMS: Statin therapy is associated with improved endothelial vasodilator function. The clinical availability of ezetimibe, a potent novel cholesterol absorption inhibitor, enables to differentiate lipid-lowering effects from potential non-lipid-lowering (pleiotropic) mechanisms of statins. METHODS AND RESULTS: Forearm blood flow (FBF) responses to acetylcholine (ACH) and sodium nitroprusside (SNP) were measured by venous occlusion plethysmography in four prospectively defined groups of patients with stable coronary artery disease (CAD) before and after 4 weeks of lipid-lowering therapy. Group A (n=15): de novo monotherapy with 10 mg/day ezetimibe; Group B (n=15): 10 mg/day ezetimibe as an add-on to chronic simvastatin therapy with 20 mg/day; Group C (n=15): dose escalation from chronic 10 to 40 mg/day atorvastatin; and Group D (n=15): de novo monotherapy with 40 mg/day atorvastatin. After 4 weeks of therapy, LDL cholesterol levels were significantly reduced in all four groups. Neither ezetimibe monotherapy (Group A) nor ezetimibe combined with 20 mg simvastatin (Group B) was associated with an increase in ACH-mediated FBF responses after 4 weeks. In contrast, dose escalation of atorvastatin from 10 to 40 mg/day (Group C) or de novo therapy with 40 mg atorvastatin/day (Group D) was associated with a significant increase in ACH-mediated FBF responses (P<0.013). CONCLUSION: Thus, both statins and ezetimibe effectively lower LDL-levels within 4 weeks of therapy. However, only statin therapy is associated with improved endothelial vasodilator function, disclosing the relevance of pleiotropic effects of statins during short-term treatment of patients with CAD.


Assuntos
Anticolesterolemiantes/uso terapêutico , Azetidinas/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Acetilcolina/farmacologia , Doença da Artéria Coronariana/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Ezetimiba , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Nitroprussiato/farmacologia , Estudos Prospectivos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatadores/farmacologia
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