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BACKGROUND: Left atrial (LA) volume and left ventricular longitudinal strain (LVLS) have significant prognostic values for major cardiovascular events (MACEs). Prognostic values of LA reservoir functional indices measured by 3-dimensional (3D) speckle-tracking echocardiography (STE) were evaluated.MethodsâandâResults:A total of 264 patients, who underwent 2-dimensional (2D) echocardiography and 3DSTE for various underlying heart diseases, were followed up to record MACE. After a mean follow up of 547±435 days, 30 patients developed MACE: 7 cardiac deaths, 6 strokes, 1 non-fatal myocardial infarction, and 22 admissions for heart failure (5 of these had cardiac death after discharge, whereas 1 sustained stroke after discharge). Receiver operating characteristic curve analysis was performed to determine the optimal cut-off levels of 4 LA functional indices: LA emptying fraction (LAEmpF), LA longitudinal strain (LALS), LA circumferential strain (LACS), and LA area change ratio (LAAC), using 3DSTE. Among these factors, 2DLVLS, 3DLAEmpF, and 3DLALS demonstrated a higher hazard ratio (>5.0) than other variables. The 3DLAEmpF and 3DLALS had a higher average treatment effect (ATE) and ATE on the treated (ATT), respectively, than the other indices after propensity score matching. Addition of 3DLAEmpF to the base model using clinical variables and LV ejection fraction or 2DLVLS demonstrated higher prognostic power. CONCLUSIONS: LAEmpF calculated using 3DSTE possessed additive prognostic values for the prediction of MACE.
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Ecocardiografia Tridimensional , Átrios do Coração , Ecocardiografia , Átrios do Coração/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Prognóstico , Volume SistólicoRESUMO
BACKGROUND: Early reported beneficial effects of cardiac rehabilitation (CR) have recently been disputed. The present study aimed to investigate the clinical impact of CR on the mid-term outcomes of patients following ST-segment elevation myocardial infarction (STEMI) treated with currently available management. METHODS: This study reviewed 145 consecutive patients who underwent primary coronary intervention and were discharged without any disability after STEMI during 2013-2015. RESULTS: Among the patients, 66 (45.5%) completed an outpatient CR program (CR group) and 79 were their non-CR counterparts or patients who dropped out of the program (N-D group). There were no between-group differences in patient demographics and clinical profiles, including door-to-balloon times and prescriptions. A total of 27 patients developed major adverse cardiac and cerebrovascular events (MACCE) during follow-up. The MACCE-free survival rates were 88% and 76% in the CR and N-D groups, respectively (log-rank, p=0.04). Cox proportional analysis demonstrated that inclusion in the N-D group was a significant predictor of MACCEs (HR, 2.36; 95% CI, 1.07-5.74; p=0.03). In the CR group, peak oxygen consumption and ventilatory efficiency determined by cardiopulmonary exercise testing significantly improved after the program (p<0.01). CONCLUSIONS: The impact of CR on the mid-term prognosis of patients with STEMI, even in the current myocardial infarction management era, was beneficial.
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Reabilitação Cardíaca , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio/terapia , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Resultado do TratamentoRESUMO
BACKGROUND: The prognostic value of indices for left atrial volumes (LAV) and reservoir function measured by 3D speckle-tracking analysis (3DSTA) has not been determined. MethodsâandâResults: LA maximal and minimal volume indices (LAVImax, LAVImin), and LA emptying fraction (LAEmpF) were measured via 2D echocardiography (2DE) and 3DSTA in 514 patients (62% male, mean age: 66±15 years) with various cardiovascular diseases. Two cutoff values using normal±2SD (cutoff criterion 1) and receiver-operating characteristic analysis (cutoff criterion 2) were evaluated. During a mean follow-up of 720±383 days, MACE (cardiac death, nonfatal myocardial infarction, stroke and admission for heart failure) occurred in 98 patients. Kaplan-Meier survival analysis showed both cutoff criteria measured by 2DE and 3DSTA had significant predictive power for MACE (P<0.001). For cutoff criterion 1, 3DSTA measurements yielded higher hazard ratios than 2DE by Cox proportional hazard model. Cutoff criterion 2 using 3DSTA had higher average treatment effect values than 2DE by matching propensity scores on the outcome. Further, a regression model that included clinical variables, left ventricular ejection fraction and cutoff criterion 2 using 3DSTA-derived LAEmpF had significantly higher prognostic power than 2DE. CONCLUSIONS: LA indices measured by 3DSTA had greater prognostic power for future MACE than 2DE. In particular, 3DSTA-derived LAEmpF has the potential to be a valuable prognostic tool in clinical settings.
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Função do Átrio Esquerdo , Átrios do Coração/patologia , Cardiopatias/diagnóstico , Prognóstico , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia/métodos , Ecocardiografia Tridimensional/métodos , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Volume SistólicoRESUMO
Anderson-Fabry disease is a rare X-linked lysosomal storage disease caused by α-galactosidase A (α-GalA) gene variants and characterized by a large genotypic and phenotypic spectrum. Enzyme replacement therapy (ERT) using recombinant α-GalA has been approved for > 10 years as a specific therapy for the disease. However, the long-term clinical efficacy for cardiac manifestations has been equivocal because it depends on several factors such as genotype, sex, age, and disease severity at the initiation of ERT. We report the differences in the clinical effects of ERT continued for > 10 years in three patients with the same genotype. Left ventricular hypertrophy and myocardial dysfunction progressed in the heterozygote proband even under ERT, although disease progression was prevented in two sons of Case 1.
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Terapia de Reposição de Enzimas/métodos , Doença de Fabry/tratamento farmacológico , Hipertrofia Ventricular Esquerda/etiologia , Adulto , Fibrilação Atrial/complicações , Progressão da Doença , Ecocardiografia , Eletrocardiografia , Doença de Fabry/enzimologia , Doença de Fabry/genética , Feminino , Insuficiência Cardíaca/complicações , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Isoenzimas/administração & dosagem , Isoenzimas/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento , alfa-Galactosidase/administração & dosagem , alfa-Galactosidase/genética , alfa-Galactosidase/uso terapêuticoRESUMO
The aim of the present study was to clarify the characteristics of Japanese critical limb ischemia (CLI) patients and analyze the rates of real-world mortality and amputation-free survival (AFS) in all patients with Fontaine stage IV CLI who were treated with/without revascularization therapy by an intra-hospital multidisciplinary care team. All consecutive patients who presented with CLI at Showa University Fujigaoka Hospital between April 2008 and March 2014 were prospectively registered. The intra-hospital committee consisted of cardiologists, plastic surgeons, dermatologists, diabetologists, nephrologists, cardiovascular surgeons, and vascular technologists. The primary endpoint of this study was all-cause mortality and AFS during the follow-up period. The present study included 145 patients with Fontaine stage IV CLI. The mean age was 76.5 ± 10.2 years. The all-cause mortality rate during the follow-up period (15.5 ± 16.1 months) was 21.4 %. The AFS rate during the follow-up period (14.1 ± 16.4 months) was 58.6 %. A multivariate Cox proportional hazards regression analysis found that age >75 years and hemodialysis were significantly associated with all-cause mortality; and that age >75 years, Rutherford 6, and wound infection were significantly associated with AFS. A multidisciplinary approach and comprehensive care may improve the outcomes and optimize the collaborative treatment of CLI patients. However, all-cause mortality remained high in patients with Fontaine stage IV CLI and early referral to a hospital that can provide specialized treatment for CLI, before the occurrence of major tissue loss or infection, is necessary to avoid primary amputation.
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Comunicação Interdisciplinar , Isquemia/fisiopatologia , Salvamento de Membro/métodos , Equipe de Assistência ao Paciente/organização & administração , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/cirurgia , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Estado Terminal , Procedimentos Endovasculares , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Extremidade Inferior/irrigação sanguínea , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Sistema de Registros , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
Although muscle wasting and/or degeneration are prevalent in patients with chronic kidney disease, it remains unknown whether FGF-23 influences muscle homeostasis and regeneration. Mesenchymal stem cells (MSCs) in skeletal muscle are distinct from satellite cells and have a known association with muscle degeneration. In this study we sought to investigate the effects of FGF-23 on MSCs isolated from human skeletal muscle in vitro. The MSCs expressed FGF receptors (1 through 4) and angiotensin-II type 1 receptor, but no traces of the Klotho gene were detected. MSCs and satellite cells were treated with FGF-23 and angiotensin-II for 48 h. Treatment with FGF-23 significantly decreased the number of MSCs compared to controls, while treatment with angiotensin-II did not. FGF-23 and angiotensin-II both left the cell counts of the satellite cells unchanged. The FGF-23-treated MSCs exhibited the senescent phenotype, as judged by senescence-associated ß-galactosidase assay, cell morphology, and increased expression of p53 and p21 in western blot analysis. FGF-23 also significantly altered the gene expression of oxidative stress regulators in the cells. In conclusion, FGF-23 induced premature senescence in MSCs from skeletal muscle via the p53/p21/oxidative-stress pathway. The interaction between the MSCs and FGF-23 may play a key role in the impaired muscle reparative mechanisms of chronic kidney disease.
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Senescência Celular/fisiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Fator de Crescimento de Fibroblastos 23 , HumanosRESUMO
Transplantation of culture-expanded adult stem/progenitor cells often results in poor cellular engraftment, survival, and migration into sites of tissue injury. Mesenchymal cells including fibroblasts and stromal cells secrete factors that protect injured tissues, promote tissue repair, and support many types of stem/progenitor cells in culture. We hypothesized that secreted factors in conditioned medium (CdM) from adult bone marrow-derived multipotent stromal cells (MSCs) could be used to prime adult cardiac stem/progenitor cells (CSCs/CPCs) and improve graft success after myocardial infarction (MI). Incubation of adult rat CPCs in CdM from human MSCs isolated by plastic adherence or by magnetic sorting against CD271 (a.k.a., p75 low-affinity nerve growth factor receptor; p75MSCs) induced phosphorylation of STAT3 and Akt in CPCs, supporting their proliferation under normoxic conditions and survival under hypoxic conditions (1% oxygen). Priming CSCs with 30× p75MSC CdM for 30 minutes prior to transplantation into subepicardial tissue 1 day after MI markedly increased engraftment compared with vehicle priming. Screening CdM with neutralizing/blocking antibodies identified connective tissue growth factor (CTGF) and Insulin as key factors in p75MSC CdM that protected CPCs. Human CTGF peptide (CTGF-D4) and Insulin synergistically promoted CPC survival during hypoxia in culture. Similar to CdM priming, priming of CSCs with CTGF-D4 and Insulin for 30 minutes prior to transplantation promoted robust engraftment, survival, and migration of CSC derivatives at 1 week and 1 month after MI. Our results indicate that short-term priming of human CSCs with CTGF-D4 and Insulin may improve graft success and cardiac regeneration in patients with MI.
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Infarto do Miocárdio/terapia , Miocárdio/patologia , Transplante de Células-Tronco , Células-Tronco/citologia , Células-Tronco/metabolismo , Adulto , Animais , Bovinos , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Meios de Cultivo Condicionados/farmacologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Infusões Intra-Arteriais , Insulina/metabolismo , Ligantes , Células-Tronco Multipotentes/citologia , Infarto do Miocárdio/patologia , Substâncias Protetoras/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Fator de Transcrição STAT3/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/enzimologia , Células Estromais/citologia , Células Estromais/efeitos dos fármacosRESUMO
The KPs (kisspeptins) are a family of multifunctional peptides with established roles in cancer metastasis, puberty and vasoconstriction. The effects of KPs on endothelial cells have yet to be determined. The aim of the present study was to investigate the effects of KP-10 on endothelial cell growth and the mechanisms underlying those effects. The administration of recombinant KP-10 into the hindlimbs of rats with ischaemia significantly impaired blood flow recovery, as shown by laser Doppler, and capillary growth, as shown using histology, compared with the controls. HUVECs (human umbilical vein endothelial cells) express the KP receptor and were treated with KP-10 in culture studies. KP-10 inhibited endothelial cell tube formation and proliferation in a significant and dose-dependent manner. The HUVECs treated with KP exhibited the senescent phenotype, as determined using a senescence-associated ß-galactosidase assay, cell morphology analysis, and decreased Sirt1 (sirtuin 1) expression and increased p53 expression shown by Western blot analysis. Intriguingly, a pharmacological Rho kinase inhibitor, Y-27632, was found to increase the proliferation of HUVECs and to reduce the number of senescent phenotype cells affected by KP-10. In conclusion, KP-10 suppressed endothelial cells growth both in vivo and in vitro in the present study. The adverse effect of KP on endothelial cells was attributable, at least in part, to the induction of cellular senescence.
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Senescência Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Kisspeptinas/farmacologia , Amidas/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Circulação Colateral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Inibidores Enzimáticos/farmacologia , Membro Posterior/irrigação sanguínea , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Isquemia/fisiopatologia , Kisspeptinas/administração & dosagem , Masculino , Piridinas/farmacologia , Ratos , Ratos Wistar , Proteínas Recombinantes/farmacologia , Quinases Associadas a rho/antagonistas & inibidoresRESUMO
AIMS: Left atrial (LA) volume index (LAVI) in chronic heart failure (HF) predicts cardiovascular outcomes. However, the association between LAVI reduction during acute decompensated HF (ADHF) and its prognostic potential is limited. We hypothesized that LA reverse remodelling (LARR) after ADHF therapy would be associated with better clinical outcomes. METHODS: This retrospective study analysed clinical outcomes and the LAVI reduction rate of 363 out of 861 patients hospitalized for ADHF who underwent two-point echocardiography at admission and discharge between January 2015 and December 2019. The mean age was 74.3 ± 13.6 years, and the mean ejection fraction (EF) was 38.9 ± 15.2%. The follow-up echocardiogram was performed 13.0 [9.5, 20] days after admission. As the median LAVI reduction rate was 7.02%, the LARR was defined as an LAVI reduction rate >7%. RESULTS: During the 34.0 ± 20.2 months of follow-up, 117 patients (32.2%) reached the primary endpoint defined as cardiovascular death and rehospitalization for ADHF. Kaplan-Meier survival analysis showed that patients with LARR had a better prognosis. Multivariate analysis indicated that LARR was an independent predictor of cardiovascular events. Similar findings were observed in the subgroup analyses of patients with persistent/permanent atrial fibrillation and those with non-HF with reduced EF. Among patients who were brain natriuretic peptide (BNP) responders, defined as a relative reduction of >70% in BNP from admission to discharge, non-LARR was observed in 41.6%. BNP responders without LARR experienced worse prognoses. CONCLUSIONS: LARR in the early vulnerable phase after hospitalization for ADHF was associated with better long-term clinical outcomes.
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Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome (ACS), which typically occurs in women at low risk of atherosclerosis. We herein report a case of SCAD in a 57-year-old man who later developed Takayasu arteritis. The patient presented to our hospital complaining of chest pain and was diagnosed with unstable angina. Emergent coronary angiography was performed, and optical coherence tomography revealed that ACS was caused by SCAD. The patient was treated medically without further ballooning or stenting. Because there was a bilateral difference in blood pressure, the systemic artery was screened by contrast-enhanced computed tomography, which showed left subclavian artery occlusion, proximal stenosis of the superior mesenteric artery, right common iliac artery dissection, and left external iliac artery dissection. Based on these results and 18F-fluorodeoxyglucose positron emission tomography findings, we diagnosed Takayasu arteritis. Prednisolone and tocilizumab were selected for medical treatment, and the patient was in a good condition at one year after the diagnosis. Takayasu arteritis can cause dissection of various arteries and should be suspected when atypical SCAD or multiple dissections are present. Early initiation of immunosuppressive therapy can control disease activity. Learning objective: Spontaneous coronary artery dissection (SCAD) is an important cause of acute coronary syndrome. In this case, we experienced a case of SCAD which turned out to be the first symptom of Takayasu arteritis. Immunosuppressive therapy was effective for both coronary lesion and systemic vasculitis. Not only fibromuscular dysplasia, but also various types of vasculitis should therefore be considered in the differential diagnosis when encountering atypical SCAD cases.
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The aim of this study was to investigate the angiogenic potential of skeletal muscle mesenchymal stem/stromal cells (mMSCs). Platelet-derived growth factor receptor (PDGFR)-α positive mMSCs secreted vascular endothelial growth factor (VEGF) and hepatocyte growth factor when cultured in an ELISA assay. The mMSC-medium significantly induced endothelial tube formation in an in vitro angiogenesis assay. The mMSC implantation promoted capillary growth in rat limb ischemia models. Upon identifying the erythropoietin receptor (Epo-R) in the mMSCs, we examined how Epo affected the cells. Epo stimulation enhanced the phosphorylation of Akt and STAT3 in the mMSCs and significantly promoted cellular proliferation. Next, Epo was directly administered into the rats' ischemic hindlimb muscles. PDGFR-α positive mMSCs in the interstitial area of muscles expressed VEGF and proliferating cell markers. The proliferating cell index was significantly higher in the ischemic limbs of Epo-treated rats than in untreated controls. Investigations by laser Doppler perfusion imaging and immunohistochemistry demonstrated significantly improved perfusion recovery and capillary growth in the Epo-treated groups versus the control groups. Taken together, the results of this study demonstrated that mMSCs possessed a pro-angiogenic property, were activated by Epo, and potentially contributed to capillary growth in skeletal muscle after ischemic injury.
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Limited data are available on athlete's heart for rugby athletes. This study aimed to investigate cardiac structure and its relationship with cardiorespiratory fitness in young Japanese rugby athletes. A prospective cross-sectional study using echocardiography and cardiopulmonary exercise testing (CPET) was conducted on 114 male collegiate rugby players. There was a higher prevalence of increased left ventricular (LV), atrial, and aortic dimensions in the young athletes than that in previously published reports, whereas the wall thickness was within the normal range. Anthropometry and CPET analyses indicated that the forwards and backs presented muscular and endurance phenotypes, respectively. Indexed LV and aortic dimensions were significantly larger in the backs than in the forwards, and the dimensions significantly correlated with oxygen uptake measured by CPET. On the four-tiered classification for LV hypertrophy, abnormal LV geometry was found in 16% of the athletes. Notably, the resting systolic blood pressure was significantly higher in athletes with concentric abnormal geometry than in the other geometry groups, regardless of their field positions. Japanese young athletes may exhibit unique phenotypes of cardiac remodeling in association with their fitness characteristics. The four-tiered LV geometry classification potentially offers information regarding the subclinical cardiovascular risks of young athletes.
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INTRODUCTION: The current treatment for heart disease consists of exercise therapy in addition to pharmacotherapy, nutritional support and lifestyle guidance. In general, nutritional support focuses on protein, salt and energy restrictions, with no active protein or amino acid intake in cases involving moderate or higher renal failure. From this perspective, patients with cardiac disease are at high risk of frailty.Beta-hydroxy beta-methyl butyrate (HMB) is a metabolite of leucine. HMB is widely used for muscle strengthening and can be safely ingested even by patients with renal failure. The proposed study protocol will investigate the effects of HMB-calcium (HMB-Ca) administered in combination with comprehensive cardiac rehabilitation for muscle strength, muscle mass and cardiac function in patients with cardiac disease during the convalescent period. The primary outcome will be knee extensor strength. Secondary outcomes will be gross isometric limb strength and skeletal muscle mass. METHODS AND ANALYSIS: This study will be a single-blinded, randomised, controlled trial with parallel comparisons between two groups. The study period will be 60 days from the start of outpatient cardiac rehabilitation. Participants will be randomly divided into two groups: an HMB group consuming HMB-Ca one time per day for 60 days; and a Placebo group consuming reduced maltose once one time per day for 60 days. Exercise therapy will be performed by both groups. ETHICS AND DISSEMINATION: The study protocol will be published in a peer-reviewed journal. Ethics approval was provided by the Showa University Clinical Research Review Board. TRIAL REGISTRATION NUMBER: jRCTs031220139; Japan Registry of Clinical Trails.
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Cálcio , Cardiopatias , Humanos , Músculo Esquelético/fisiologia , Suplementos Nutricionais , Terapia por Exercício , Cálcio da Dieta , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Erythropoietin (EPO) has recently been shown to confer cardioprotective effects via angiogenesis and antiapoptosis. The administration of EPO after myocardial infarction (MI) reduces infarct size and improves cardiac function in small animals. The purpose of this study is to investigate the protective effects of EPO in porcine MI. Each animal in the EPO group received four injections of recombinant human EPO (rhEPO; 6000 U per injection) at 2-day intervals, starting after coronary occlusion. Animals in the control group received saline. Left ventriculography was performed just after coronary occlusion and at 28 days. Time-course changes in serum levels of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and fibroblast growth factor (FGF) were measured. The number of vessels was calculated, and the mRNA expressions of VEGF and insulin-like growth factor (IGF) were examined. Left ventricular function was similar between the groups. The numbers of cells positive for anti-α-smooth muscle actin, von Willebrand factor, and c-kit were significantly higher in the EPO group than in the controls (P < 0.05). The EPO group exhibited significantly higher HGF and FGF concentrations (P < 0.05) and higher expression of VEGF and IGF mRNA (P < 0.05) compared with the controls. In conclusion, EPO accelerates angiogenesis via the upregulation of systemic levels such as HGF and FGF, and the local expression of VEGF and IGF, in porcine MI.
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Indutores da Angiogênese/farmacologia , Eritropoetina/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Fatores de Crescimento de Fibroblastos/sangue , Fator de Crescimento de Hepatócito/sangue , Humanos , Imuno-Histoquímica , Infarto do Miocárdio/sangue , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia , Neovascularização Fisiológica/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Recuperação de Função Fisiológica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Somatomedinas/genética , Volume Sistólico , Sus scrofa , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genética , Função Ventricular EsquerdaRESUMO
Few reports have examined the effects of adult bone marrow multipotent stromal cells (MSCs) on large animals, and no useful method has been established for MSC implantation. In this study, we investigate the effects of MSC infusion from the coronary vein in a swine model of chronic myocardial infarction (MI). MI was induced in domestic swine by placing beads in the left coronary artery. Bone marrow cells were aspirated and then cultured to isolate the MSCs. At 4 weeks after MI, MSCs labeled with dye (n=8) or vehicle (n=5) were infused retrogradely from the anterior interventricular vein without any complications. Left ventriculography (LVG) was performed just before and at 4 weeks after cell infusion. The ejection fraction (EF) assessed by LVG significantly decreased from baseline up to a follow-up at 4 weeks in the control group (P<0.05), whereas the cardiac function was preserved in the MSC group. The difference in the EF between baseline and follow-up was significantly greater in the MSC group than in the control group (P<0.05). The MSC administration significantly promoted neovascularization in the border areas compared with the controls (P<0.0005), though it had no affect on cardiac fibrosis. A few MSCs expressed von Willebrand factor in a differentiation assay, but none of them expressed troponin T. In quantitative gene expression analysis, basic fibroblast growth factor and vascular endothelial growth factor (VEGF) levels were significantly higher in the MSC-treated hearts than in the controls (P<0.05, respectively). Immunohistochemical staining revealed VEGF production in the engrafted MSCs. In vitro experiment demonstrated that MSCs significantly stimulated endothelial capillary network formation compared with the VEGF protein (P<0.0001). MSC infusion via the coronary vein prevented the progression of cardiac dysfunction in chronic MI. This favorable effect appeared to derive not from cell differentiation, but from enhanced neovascularization by angiogenic factors secreted from the MSCs.
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Transplante de Medula Óssea/métodos , Coração/fisiopatologia , Células-Tronco Multipotentes/transplante , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/cirurgia , Neovascularização Fisiológica , Células Estromais/transplante , Animais , Diferenciação Celular , Doença Crônica , Vasos Coronários , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibrose , Infusões Intravenosas , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/patologia , Infarto do Miocárdio/complicações , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/patologia , Miocárdio/patologia , Fenótipo , Células Estromais/metabolismo , Células Estromais/patologia , Suínos , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
RATIONALE: Human heregulins, neuregulin-1 type I polypeptides that activate proliferation, differentiation, and survival of glial cells, neurons, and myocytes, are expressed in macrophage foam cells within human coronary atherosclerotic lesions. Macrophage foam cell formation, characterized by cholesterol ester accumulation, is modulated by scavenger receptor class A (SR-A), acyl-coenzyme A:cholesterol acyltransferase (ACAT)1, and ATP-binding cassette transporter (ABC)A1. OBJECTIVE: The present study clarified the roles of heregulins in macrophage foam cell formation and atherosclerosis. METHODS AND RESULTS: Plasma heregulin-beta(1) levels were significantly decreased in 31 patients with acute coronary syndrome and 33 patients with effort angina pectoris compared with 34 patients with mild hypertension and 40 healthy volunteers (1.3+/-0.3, 2.0+/-0.4 versus 7.6+/-1.4, 8.2+/-1.2 ng/mL; P<0.01). Among all patients with acute coronary syndrome and effort angina pectoris, plasma heregulin-beta(1) levels were further decreased in accordance with the severity of coronary artery lesions. Expression of heregulin-beta(1) was observed at trace levels in intracoronary atherothrombosis obtained by aspiration thrombectomy from acute coronary syndrome patients. Heregulin-beta(1), but not heregulin-alpha, significantly reduced acetylated low-density lipoprotein-induced cholesterol ester accumulation in primary cultured human monocyte-derived macrophages by reducing SR-A and ACAT1 expression and by increasing ABCA1 expression at both mRNA and protein levels. Heregulin-beta(1) significantly decreased endocytic uptake of [(125)I]acetylated low-density lipoprotein and ACAT activity, and increased cholesterol efflux to apolipoprotein (Apo)A-I from human macrophages. Chronic infusion of heregulin-beta(1) into ApoE(-/-) mice significantly suppressed the development of atherosclerotic lesions. CONCLUSIONS: This study provided the first evidence that heregulin-beta(1) inhibits atherogenesis and suppresses macrophage foam cell formation via SR-A and ACAT1 downregulation and ABCA1 upregulation.
Assuntos
Aterosclerose/prevenção & controle , Doença da Artéria Coronariana/prevenção & controle , Células Espumosas/metabolismo , Neuregulina-1/sangue , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/sangue , Angina Pectoris/etiologia , Animais , Anticorpos/administração & dosagem , Apolipoproteína A-I/metabolismo , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/sangue , Aterosclerose/complicações , Transporte Biológico , Biomarcadores/sangue , Antígenos CD36/metabolismo , Células Cultivadas , Ésteres do Colesterol/metabolismo , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/complicações , Modelos Animais de Doenças , Regulação para Baixo , Endocitose , Feminino , Humanos , Hipertensão/sangue , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Neuregulina-1/administração & dosagem , Neuregulina-1/imunologia , Neuregulina-1/metabolismo , RNA Mensageiro/metabolismo , Ruptura , Receptores Depuradores Classe A/genética , Receptores Depuradores Classe A/metabolismo , Receptores Depuradores Classe B/metabolismo , Índice de Gravidade de Doença , Fatores de TempoRESUMO
OBJECTIVES: In the field of exercise physiology, there has been great interest in exploring circulating microRNAs (miRs) as potential biomarkers. However, it remains to be determined whether circulating miRs reflect cardiorespiratory fitness. The aim of this study was to investigate the association between circulating levels of specific miRs and cardiorespiratory fitness evaluated by cardiopulmonary exercise testing (CPET) after acute myocardial infarction (MI). METHODS: Twenty patients who had had an acute MI were included. All patients underwent CPET in the convalescent phase. Quantitative real-time polymerase chain reaction analyses for miR-181 members (a/b/c) and miR-484 were performed to determine the expression levels in the peripheral blood of the included patients and healthy control subjects (n=5). RESULTS: Post-MI patients showed impaired exercise tolerance and ventilatory efficiency in CPET analysis. Compared with controls, circulating levels of miR-181a and 181c were gradually and significantly elevated through the 1st to 7th days after acute MI, whereas miR-181b and miR-484 were not. Circulating miR levels did not correlate with clinical or echocardiographic parameters. However, circulating levels of miR-181c and miR-484 on the 7th day showed significant positive correlations with the anaerobic threshold and peak oxygen consumption from CPET analysis. Moreover, miR-181c levels were inversely associated with the ventilatory inefficiency index. Patients with high exercise capacity after MI showed significantly higher expressions of circulating miR-181c and miR-484 than those with low exercise capacity. CONCLUSIONS: The results of this pilot study suggest that circulating levels of miR-181c and miR-484 after acute MI may be predictive biomarkers of post-MI cardiorespiratory fitness.
RESUMO
A 54-year-old male bodybuilder who was abusing anabolic steroids developed an acute ST-segment elevation myocardial infarction after strenuous strength training. Despite optimal use of dual antiplatelet therapy, on day 4 after primary coronary stenting, the patient suffered another acute coronary event due to subacute thrombosis, potentially pre-disposed by anabolic steroid use. (Level of Difficulty: Intermediate.).