RESUMEN
Dysregulated autophagy is associated with cardiovascular and metabolic diseases, where impaired flow-mediated endothelial cell responses promote cardiovascular risk. The mechanism by which the autophagy machinery regulates endothelial functions is complex. We applied multi-omics approaches and in vitro and in vivo functional assays to decipher the diverse roles of autophagy in endothelial cells. We demonstrate that autophagy regulates VEGF-dependent VEGFR signaling and VEGFR-mediated and flow-mediated eNOS activation. Endothelial ATG5 deficiency in vivo results in selective loss of flow-induced vasodilation in mesenteric arteries and kidneys and increased cerebral and renal vascular resistance in vivo. We found a crucial pathophysiological role for autophagy in endothelial cells in flow-mediated outward arterial remodeling, prevention of neointima formation following wire injury, and recovery after myocardial infarction. Together, these findings unravel a fundamental role of autophagy in endothelial function, linking cell proteostasis to mechanosensing.
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Células Endoteliales , Infarto del Miocardio , Humanos , Autofagia , Proteína 5 Relacionada con la Autofagia/genética , Proteína 5 Relacionada con la Autofagia/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Arterias Mesentéricas/metabolismo , Infarto del Miocardio/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Transducción de Señal , Vasodilatación , Animales , RatonesRESUMEN
[Figure: see text].
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Aterosclerosis/etiología , Desdiferenciación Celular , MicroARNs/metabolismo , Músculo Liso Vascular/fisiología , ARN Largo no Codificante/fisiología , Animales , Aterosclerosis/patología , Movimiento Celular , Proliferación Celular , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Vasos Coronarios/citología , Regulación hacia Abajo , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Humanos , Metabolismo de los Lípidos , Ratones , Músculo Liso Vascular/citología , Oligonucleótidos Antisentido , Fenotipo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , TranscriptomaRESUMEN
[Figure: see text].
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Transición Epitelial-Mesenquimal , Hipertensión Pulmonar/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/patología , Ratones , Proteína de Unión al Tracto de Polipirimidina/metabolismo , ARN Largo no Codificante/genética , Transcriptoma , Remodelación VascularRESUMEN
Preexisting immune responses toward adenoviral vectors limit the use of a vector based on particular serotypes and its clinical applicability for gene therapy and/or vaccination. Therefore, there is a significant interest in vectorizing novel adenoviral types that have low seroprevalence in the human population. Here, we describe the discovery and vectorization of a chimeric human adenovirus, which we call HAdV-20-42-42. Full-genome sequencing revealed that this virus is closely related to human serotype 42, except for the penton base, which is derived from serotype 20. The HAdV-20-42-42 vector could be propagated stably to high titers on existing E1-complementing packaging cell lines. Receptor-binding studies revealed that the vector utilized both CAR and CD46 as receptors for cell entry. Furthermore, the HAdV-20-42-42 vector was potent in transducing human and murine cardiovascular cells and tissues, irrespective of the presence of blood coagulation factor X. In vivo characterizations demonstrate that when delivered intravenously (i.v.) in mice, HAdV-20-42-42 mainly targeted the lungs, liver, and spleen and triggered robust inflammatory immune responses. Finally, we demonstrate that potent T-cell responses against vector-delivered antigens could be induced upon intramuscular vaccination in mice. In summary, from the data obtained we conclude that HAdV-20-42-42 provides a valuable addition to the portfolio of adenoviral vectors available to develop efficacious products in the fields of gene therapy and vaccination. IMPORTANCE Adenoviral vectors are under investigation for a broad range of therapeutic indications in diverse fields, such as oncology and gene therapy, as well as for vaccination both for human and veterinary use. A wealth of data shows that preexisting immune responses may limit the use of a vector. Particularly in the current climate of global pandemic, there is a need to expand the toolbox with novel adenoviral vectors for vaccine development. Our data demonstrate that we have successfully vectorized a novel adenovirus type candidate with low seroprevalence. The cell transduction data and antigen-specific immune responses induced in vivo demonstrate that this vector is highly promising for the development of gene therapy and vaccine products.
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Adenovirus Humanos , Terapia Genética/métodos , Vectores Genéticos , Desarrollo de Vacunas/métodos , Células A549 , Adenovirus Humanos/genética , Adenovirus Humanos/inmunología , Animales , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Células HEK293 , Humanos , Masculino , Ratones , Estudios SeroepidemiológicosRESUMEN
Glucocorticoids are steroid hormones with key roles in the regulation of many physiological systems including energy homeostasis and immunity. However, chronic glucocorticoid excess, highlighted in Cushing's syndrome, is established as being associated with increased cardiovascular disease (CVD) risk. Atherosclerosis is the major cause of CVD, leading to complications including coronary artery disease, myocardial infarction and heart failure. While the associations between glucocorticoid excess and increased prevalence of these complications are well established, the mechanisms underlying the role of glucocorticoids in development of atheroma are unclear. This review aims to better understand the importance of glucocorticoids in atherosclerosis and to dissect their cell-specific effects on key processes (e.g., contractility, remodelling and lesion development). Clinical and pre-clinical studies have shown both athero-protective and pro-atherogenic responses to glucocorticoids, effects dependent upon their multifactorial actions. Evidence indicates regulation of glucocorticoid bioavailability at the vasculature is complex, with local delivery, pre-receptor metabolism, and receptor expression contributing to responses linked to vascular remodelling and inflammation. Further investigations are required to clarify the mechanisms through which endogenous, local glucocorticoid action and systemic glucocorticoid treatment promote/inhibit atherosclerosis. This will provide greater insights into the potential benefit of glucocorticoid targeted approaches in the treatment of cardiovascular disease.
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Aterosclerosis/tratamiento farmacológico , Aterosclerosis/fisiopatología , Glucocorticoides/farmacología , Aterosclerosis/metabolismo , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Síndrome de Cushing , Glucocorticoides/metabolismo , Humanos , Inflamación/tratamiento farmacológico , Receptores de Glucocorticoides/metabolismo , Factores de RiesgoRESUMEN
Sex differences in cardiovascular disease (CVD), including aortic stenosis, atherosclerosis and cardiovascular calcification, are well documented. High levels of testosterone, the primary male sex hormone, are associated with increased risk of cardiovascular calcification, whilst estrogen, the primary female sex hormone, is considered cardioprotective. Current understanding of sexual dimorphism in cardiovascular calcification is still very limited. This review assesses the evidence that the actions of sex hormones influence the development of cardiovascular calcification. We address the current question of whether sex hormones could play a role in the sexual dimorphism seen in cardiovascular calcification, by discussing potential mechanisms of actions of sex hormones and evidence in pre-clinical research. More advanced investigations and understanding of sex hormones in calcification could provide a better translational outcome for those suffering with cardiovascular calcification.
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Andrógenos/fisiología , Estrógenos/fisiología , Enfermedades de las Válvulas Cardíacas/etiología , Calcificación Vascular/etiología , Animales , Modelos Animales de Enfermedad , Enfermedades de las Válvulas Cardíacas/metabolismo , Humanos , Transducción de Señal , Calcificación Vascular/metabolismoRESUMEN
KEY POINTS: Type 1 diabetes mellitus increases cardiovascular risk; hypertension amplifies this risk, while pressure natriuresis regulates long-term blood pressure. We induced type 1 diabetes in rats by streptozotocin injection and demonstrated a substantial impairment of pressure natriuresis: acute increases in blood pressure did not increase renal medullary blood flow, tubular sodium reabsorption was not downregulated, and proximal tubule sodium reabsorption, measured by lithium clearance, was unaffected. Insulin reduced blood glucose in diabetic rats, and rescued the pressure natriuresis response without influencing lithium clearance, but did not restore medullary blood flow. Radiotelemetry showed that diastolic blood pressure was increased in diabetic rats, and its diurnal variation was reduced. Increases in medullary blood flow and decreases in distal tubule sodium reabsorption that offset acute rises in BP are impaired in early type 1 diabetes, and this impairment could be a target for preventing hypertension in type 1 diabetes. ABSTRACT: Type 1 diabetes mellitus (T1DM) substantially increases cardiovascular risk, and hypertension amplifies this risk. Blood pressure (BP) and body sodium homeostasis are linked. T1DM patients have increased total exchangeable sodium, correlating directly with BP. Pressure natriuresis is an important physiological regulator of BP. We hypothesised that pressure natriuresis would be impaired, and BP increased, in the early phase of T1DM. Male Sprague-Dawley rats were injected with streptozotocin (30-45 mg/kg) or citrate vehicle. After 3 weeks, pressure natriuresis was induced by serial arterial ligation. In non-diabetic controls, this increased fractional excretion of sodium from â¼1% to â¼25% of the filtered load (P < 0.01); in T1DM rats, the response was significantly blunted, peaking at only â¼3% (P < 0.01). Mechanistically, normal lithium clearance suggested that distal tubule sodium reabsorption was not downregulated with increased BP in T1DM rats. The pressure dependence of renal medullary perfusion, considered a key factor in the integrated response, was abolished. Insulin therapy rescued the natriuretic response in diabetic rats, restoring normal downregulation of tubular sodium reabsorption when BP was increased. However, the pressure dependence of medullary perfusion was not restored, suggesting persistent vascular dysfunction despite glycaemic control. Radiotelemetry showed that T1DM did not affect systolic BP, but mean diastolic BP was â¼5 mmHg higher than in non-diabetic controls (P < 0.01), and normal diurnal variation was reduced. In conclusion, functional impairment of renal sodium and BP homeostasis is an early manifestation of T1DM, preceding hypertension and nephropathy. Early intervention to restore pressure natriuresis in T1DM may complement reductions in cardiovascular risk achieved with glycaemic control.
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Presión Sanguínea/fisiología , Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Tipo 1/fisiopatología , Natriuresis/fisiología , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulación hacia Abajo/fisiología , Hemodinámica/fisiología , Hipertensión/fisiopatología , Riñón/metabolismo , Riñón/fisiopatología , Litio/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Circulación Renal/fisiología , Sodio/metabolismoRESUMEN
Pluripotent stem cell-derived differentiated endothelial cells offer high potential in regenerative medicine in the cardiovascular system. With the aim of translating the use of a human stem cell-derived endothelial cell product (hESC-ECP) for treatment of critical limb ischemia (CLI) in man, we report a good manufacturing practice (GMP)-compatible protocol and detailed cell tracking and efficacy data in multiple preclinical models. The clinical-grade cell line RC11 was used to generate hESC-ECP, which was identified as mostly endothelial (60% CD31+/CD144+), with the remainder of the subset expressing various pericyte/mesenchymal stem cell markers. Cell tracking using MRI, PET, and qPCR in a murine model of limb ischemia demonstrated that hESC-ECP was detectable up to day 7 following injection. Efficacy in several murine models of limb ischemia (immunocompromised/immunocompetent mice and mice with either type I/II diabetes mellitus) demonstrated significantly increased blood perfusion and capillary density. Overall, we demonstrate a GMP-compatible hESC-ECP that improved ischemic limb perfusion and increased local angiogenesis without engraftment, paving the way for translation of this therapy.
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Células Endoteliales/citología , Miembro Posterior/citología , Isquemia/terapia , Neovascularización Fisiológica/fisiología , Animales , Biomarcadores/metabolismo , Diferenciación Celular/fisiología , Línea Celular , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Células Endoteliales/metabolismo , Miembro Posterior/metabolismo , Humanos , Isquemia/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Pericitos/citología , Pericitos/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Trasplante de Células Madre/métodosRESUMEN
BACKGROUND: The Wilms' tumour protein (WT1), which influences tumour development and angiogenesis, is a promising therapeutic target in breast cancer. We hypothesised that WT1 expression would vary in endothelial cells in distinct sub-classifications of breast cancer. METHODS: WT1 expression and vascular density were quantified by immunohistochemical analysis of human (n = 57) and murine breast cancers. Human tumours were sub-classified by histopathological grade, ER status and HER2 enrichment. RESULTS: WT1 was identified in endothelial (and epithelial and smooth muscle) cells in tumours and tumour-free tissues (controls) from patients and mice with breast cancer. WT1 expression was higher in tumours than in controls, but this was not due to increased endothelial WT1. Vascular WT1 in cancers decreased as histopathological grade increased. WT1 was higher in ER-positive versus ER-negative cancers. Strikingly, reduced WT1 expression in controls correlated with an increased Nottingham Prognostic Index score. CONCLUSIONS: Expression of WT1 is increased in breast cancers but this is not limited to the vascular compartment. The association between reduced WT1 in tumour-free tissue and poor prognosis suggests a protective role for WT1 in the healthy breast.
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Neoplasias de la Mama/patología , Proteínas WT1/análisis , Animales , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/química , Neoplasias de la Mama/mortalidad , Femenino , Humanos , Ratones , Clasificación del Tumor , Receptor ErbB-2/análisis , Receptores de Estrógenos/análisis , Proteínas WT1/fisiologíaRESUMEN
BACKGROUND: Chronic liver scarring from any cause leads to cirrhosis, portal hypertension, and a progressive decline in renal blood flow and renal function. Extreme renal vasoconstriction characterizes hepatorenal syndrome, a functional and potentially reversible form of acute kidney injury in patients with advanced cirrhosis, but current therapy with systemic vasoconstrictors is ineffective in a substantial proportion of patients and is limited by ischemic adverse events. Serelaxin (recombinant human relaxin-2) is a peptide molecule with anti-fibrotic and vasoprotective properties that binds to relaxin family peptide receptor-1 (RXFP1) and has been shown to increase renal perfusion in healthy human volunteers. We hypothesized that serelaxin could ameliorate renal vasoconstriction and renal dysfunction in patients with cirrhosis and portal hypertension. METHODS AND FINDINGS: To establish preclinical proof of concept, we developed two independent rat models of cirrhosis that were characterized by progressive reduction in renal blood flow and glomerular filtration rate and showed evidence of renal endothelial dysfunction. We then set out to further explore and validate our hypothesis in a phase 2 randomized open-label parallel-group study in male and female patients with alcohol-related cirrhosis and portal hypertension. Forty patients were randomized 1:1 to treatment with serelaxin intravenous (i.v.) infusion (for 60 min at 80 µg/kg/d and then 60 min at 30 µg/kg/d) or terlipressin (single 2-mg i.v. bolus), and the regional hemodynamic effects were quantified by phase contrast magnetic resonance angiography at baseline and after 120 min. The primary endpoint was the change from baseline in total renal artery blood flow. Therapeutic targeting of renal vasoconstriction with serelaxin in the rat models increased kidney perfusion, oxygenation, and function through reduction in renal vascular resistance, reversal of endothelial dysfunction, and increased activation of the AKT/eNOS/NO signaling pathway in the kidney. In the randomized clinical study, infusion of serelaxin for 120 min increased total renal arterial blood flow by 65% (95% CI 40%, 95%; p < 0.001) from baseline. Administration of serelaxin was safe and well tolerated, with no detrimental effect on systemic blood pressure or hepatic perfusion. The clinical study's main limitations were the relatively small sample size and stable, well-compensated population. CONCLUSIONS: Our mechanistic findings in rat models and exploratory study in human cirrhosis suggest the therapeutic potential of selective renal vasodilation using serelaxin as a new treatment for renal dysfunction in cirrhosis, although further validation in patients with more advanced cirrhosis and renal dysfunction is required. TRIAL REGISTRATION: ClinicalTrials.gov NCT01640964.
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Enfermedades Renales/tratamiento farmacológico , Riñón/efectos de los fármacos , Cirrosis Hepática/tratamiento farmacológico , Relaxina/farmacología , Relaxina/uso terapéutico , Adolescente , Adulto , Anciano , Animales , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Riñón/irrigación sanguínea , Masculino , Persona de Mediana Edad , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Flujo Sanguíneo Regional/efectos de los fármacos , Escocia , Adulto JovenRESUMEN
BACKGROUND: Accelerated thrombus formation induced by exposure to combustion-derived air pollution has been linked to alterations in endogenous fibrinolysis and platelet activation in response to pulmonary and systemic inflammation. We hypothesised that mechanisms independent of inflammation contribute to accelerated thrombus formation following exposure to diesel exhaust particles (DEP). METHODS: Thrombosis in rats was assessed 2, 6 and 24 h after administration of DEP, carbon black (CB; control carbon nanoparticle), DQ12 quartz microparticles (to induce pulmonary inflammation) or saline (vehicle) by either intra-tracheal instillation (0.5 mg, except Quartz; 0.125 mg) or intravenous injection (0.5 mg/kg). Thrombogenicity was assessed by carotid artery occlusion, fibrinolytic variables and platelet-monocyte aggregates. Measures of inflammation were determined in plasma and bronchoalveolar lavage fluid. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI)-1 were measured following direct in vitro exposure of human umbilical vein endothelial cells (HUVECs) to DEP (10-150 µg/mL). RESULTS: Instillation of DEP reduced the time to thrombotic occlusion in vivo, coinciding with the peak of DEP-induced pulmonary inflammation (6 h). CB and DQ12 produced greater inflammation than DEP but did not alter time to thrombotic occlusion. Intravenous DEP produced an earlier (2 h) acceleration of thrombosis (as did CB) without pulmonary or systemic inflammation. DEP inhibited t-PA and PAI-1 release from HUVECs, and reduced the t-PA/PAI-1 ratio in vivo; similar effects in vivo were seen with CB and DQ12. DEP, but not CB or DQ12, increased platelet-monocyte aggregates. CONCLUSION: DEP accelerates arterial thrombus formation through increased platelet activation. This effect is dissociated from pulmonary and systemic inflammation and from impaired fibrinolytic function.
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Arteriopatías Oclusivas/inducido químicamente , Plaquetas/efectos de los fármacos , Estenosis Carotídea/sangre , Activación Plaquetaria , Neumonía/inducido químicamente , Cuarzo/toxicidad , Hollín/toxicidad , Trombosis/inducido químicamente , Emisiones de Vehículos/toxicidad , Animales , Arteriopatías Oclusivas/sangre , Plaquetas/metabolismo , Líquido del Lavado Bronquioalveolar/química , Estenosis Carotídea/inducido químicamente , Células Cultivadas , Fibrinólisis/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Mediadores de Inflamación/sangre , Masculino , Tamaño de la Partícula , Inhibidor 1 de Activador Plasminogénico/metabolismo , Adhesividad Plaquetaria/efectos de los fármacos , Neumonía/sangre , Ratas Wistar , Trombosis/sangre , Factores de Tiempo , Activador de Tejido Plasminógeno/metabolismoRESUMEN
MicroRNAs (miRNAs) directly regulate gene expression at a post-transcriptional level and represent an attractive therapeutic target for a wide range of diseases. Here, we report a novel strategy for delivering miRNAs to endothelial cells (ECs) to regulate angiogenesis, using polymer functionalized carbon nanotubes (CNTs). CNTs were coated with two different polymers, polyethyleneimine (PEI) or polyamidoamine dendrimer (PAMAM), followed by conjugation of miR-503 oligonucleotides as recognized regulators of angiogenesis. We demonstrated a reduced toxicity for both polymer-coated CNTs, compared with pristine CNTs or polymers alone. Moreover, polymer-coated CNT stabilized miR-503 oligonucleotides and allowed their efficient delivery to ECs. The functionality of PAMAM-CNT-miR-503 complexes was further demonstrated in ECs through regulation of target genes, cell proliferation and angiogenic sprouting and in a mouse model of angiogenesis. This comprehensive series of experiments demonstrates that the use of polyamine-functionalized CNTs to deliver miRNAs is a novel and effective means to regulate angiogenesis.
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Células Endoteliales , MicroARNs , Nanotubos de Carbono , Neovascularización Fisiológica/efectos de los fármacos , Animales , Poliaminas , PolietileneiminaAsunto(s)
Células de la Médula Ósea/citología , Médula Ósea/metabolismo , Células Progenitoras Endoteliales/citología , Células Madre/citología , Adulto , Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/efectos de los fármacos , Células Cultivadas , Células Progenitoras Endoteliales/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Células Madre/efectos de los fármacosRESUMEN
BACKGROUND: The exact etiology of preeclampsia is unknown, but there is growing evidence of an imbalance in angiogenic growth factors and abnormal placentation. Hydrogen sulfide (H2S), a gaseous messenger produced mainly by cystathionine γ-lyase (CSE), is a proangiogenic vasodilator. We hypothesized that a reduction in CSE activity may alter the angiogenic balance in pregnancy and induce abnormal placentation and maternal hypertension. METHODS AND RESULTS: Plasma levels of H2S were significantly decreased in women with preeclampsia (P<0.01), which was associated with reduced placental CSE expression as determined by real-time polymerase chain reaction and immunohistochemistry. Inhibition of CSE activity by DL-propargylglycine reduced placental growth factorproduction from first-trimester (8-12 weeks gestation) human placental explants and inhibited trophoblast invasion in vitro. Knockdown of CSE in human umbilical vein endothelial cells by small-interfering RNA increased the release of soluble fms-like tyrosine kinase-1 and soluble endoglin, as assessed by enzyme-linked immunosorbent assay, whereas adenoviral-mediated CSE overexpression in human umbilical vein endothelial cells inhibited their release. Administration of DL-propargylglycine to pregnant mice induced hypertension and liver damage, promoted abnormal labyrinth vascularization in the placenta, and decreased fetal growth. Finally, a slow-releasing H2S-generating compound, GYY4137, inhibited circulating soluble fms-like tyrosine kinase-1 and soluble endoglin levels and restored fetal growth in mice that was compromised by DL-propargylglycine treatment, demonstrating that the effect of CSE inhibitor was attributable to inhibition of H2S production. CONCLUSIONS: These results imply that endogenous H2S is required for healthy placental vasculature and that a decrease in CSE/H2S activity may contribute to the pathogenesis of preeclampsia.
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Cistationina gamma-Liasa/metabolismo , Sulfuro de Hidrógeno/antagonistas & inhibidores , Sulfuro de Hidrógeno/metabolismo , Hipertensión/etiología , Enfermedades Placentarias/etiología , Preeclampsia/metabolismo , Complicaciones Cardiovasculares del Embarazo/etiología , Adolescente , Adulto , Alquinos/efectos adversos , Alquinos/farmacología , Animales , Antígenos CD/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Endoglina , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Femenino , Desarrollo Fetal/efectos de los fármacos , Desarrollo Fetal/fisiología , Glicina/efectos adversos , Glicina/análogos & derivados , Glicina/farmacología , Humanos , Hipertensión/inducido químicamente , Hipertensión/metabolismo , Ratones , Ratones Endogámicos C57BL , Morfolinas/farmacología , Neovascularización Fisiológica/fisiología , Técnicas de Cultivo de Órganos , Compuestos Organotiofosforados/farmacología , Placenta/efectos de los fármacos , Placenta/metabolismo , Placenta/fisiopatología , Enfermedades Placentarias/metabolismo , Enfermedades Placentarias/fisiopatología , Factor de Crecimiento Placentario , Preeclampsia/fisiopatología , Embarazo , Complicaciones Cardiovasculares del Embarazo/metabolismo , Complicaciones Cardiovasculares del Embarazo/fisiopatología , Proteínas Gestacionales/metabolismo , Preñez , Receptores de Superficie Celular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adulto JovenRESUMEN
A decade of research has sought to identify circulating endothelial progenitor cells (EPC) in order to harness their potential for cardiovascular regeneration. Endothelial outgrowth cells (EOC) most closely fulfil the criteria for an EPC, but their origin remains obscure. Our aim was to identify the source and precursor of EOC and to assess their regenerative potential compared to mature endothelial cells. EOC are readily isolated from umbilical cord blood (6/6 donors) and peripheral blood mononuclear cells (4/6 donors) but not from bone marrow (0/6) or peripheral blood following mobilization with granulocyte-colony stimulating factor (0/6 donors). Enrichment and depletion of blood mononuclear cells demonstrated that EOC are confined to the CD34(+)CD133(-)CD146(+) cell fraction. EOC derived from blood mononuclear cells are indistinguishable from mature human umbilical vein endothelial cells (HUVEC) by morphology, surface antigen expression, immunohistochemistry, real-time polymerase chain reaction, proliferation, and functional assessments. In a subcutaneous sponge model of angiogenesis, both EOC and HUVEC contribute to de novo blood vessel formation giving rise to a similar number of vessels (7.0 ± 2.7 vs. 6.6 ± 3.7 vessels, respectively, n = 9). Bone marrow-derived outgrowth cells isolated under the same conditions expressed mesenchymal markers rather than endothelial cell markers and did not contribute to blood vessels in vivo. In this article, we confirm that EOC arise from CD34(+)CD133(-)CD146(+) mononuclear cells and are similar, if not identical, to mature endothelial cells. Our findings suggest that EOC do not arise from bone marrow and challenge the concept of a bone marrow-derived circulating precursor for endothelial cells.
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Células Endoteliales/citología , Sangre Fetal/citología , Leucocitos Mononucleares/citología , Piel/irrigación sanguínea , Antígenos CD/genética , Biomarcadores/metabolismo , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Linaje de la Célula , Células Cultivadas , Células Endoteliales/metabolismo , Sangre Fetal/metabolismo , Expresión Génica , Factor Estimulante de Colonias de Granulocitos/farmacología , Humanos , Inmunofenotipificación , Leucocitos Mononucleares/metabolismo , Neovascularización Fisiológica , Piel/citología , Técnicas de Cultivo de TejidosRESUMEN
11ß-Hydroxysteroid dehydrogenase type-1 (11ß-HSD1) converts inert cortisone into active cortisol, amplifying intracellular glucocorticoid action. 11ß-HSD1 deficiency improves cardiovascular risk factors in obesity but exacerbates acute inflammation. To determine the effects of 11ß-HSD1 deficiency on atherosclerosis and its inflammation, atherosclerosis-prone apolipoprotein E-knockout (ApoE-KO) mice were treated with a selective 11ß-HSD1 inhibitor or crossed with 11ß-HSD1-KO mice to generate double knockouts (DKOs) and challenged with an atherogenic Western diet. 11ß-HSD1 inhibition or deficiency attenuated atherosclerosis (74-76%) without deleterious effects on plaque structure. This occurred without affecting plasma lipids or glucose, suggesting independence from classical metabolic risk factors. KO plaques were not more inflamed and indeed had 36% less T-cell infiltration, associated with 38% reduced circulating monocyte chemoattractant protein-1 (MCP-1) and 36% lower lesional vascular cell adhesion molecule-1 (VCAM-1). Bone marrow (BM) cells are key to the atheroprotection, since transplantation of DKO BM to irradiated ApoE-KO mice reduced atherosclerosis by 51%. 11ß-HSD1-null macrophages show 76% enhanced cholesterol ester export. Thus, 11ß-HSD1 deficiency reduces atherosclerosis without exaggerated lesional inflammation independent of metabolic risk factors. Selective 11ß-HSD1 inhibitors promise novel antiatherosclerosis effects over and above their benefits for metabolic risk factors via effects on BM cells, plausibly macrophages.
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11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/deficiencia , Aterosclerosis/metabolismo , Médula Ósea/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Aterosclerosis/genética , Médula Ósea/efectos de los fármacos , Glucocorticoides/metabolismo , Ratones , Ratones Noqueados , Factores de Riesgo , Molécula 1 de Adhesión Celular Vascular/metabolismoRESUMEN
BACKGROUND: Clinical studies have now confirmed the link between short-term exposure to elevated levels of air pollution and increased cardiovascular mortality, but the mechanisms are complex and not completely elucidated. The present study was designed to investigate the hypothesis that activation of pulmonary sensory receptors and the sympathetic nervous system underlies the influence of pulmonary exposure to diesel exhaust particulate on blood pressure, and on the myocardial response to ischemia and reperfusion. METHODS & RESULTS: 6 h after intratracheal instillation of diesel exhaust particulate (0.5 mg), myocardial ischemia and reperfusion was performed in anesthetised rats. Blood pressure, duration of ventricular arrhythmia, arrhythmia-associated death, tissue edema and reperfusion injury were all increased by diesel exhaust particulate exposure. Reperfusion injury was also increased in buffer perfused hearts isolated from rats instilled in vivo, excluding an effect dependent on continuous neurohumoral activation or systemic inflammatory mediators. Myocardial oxidant radical production, tissue apoptosis and necrosis were increased prior to ischemia, in the absence of recruited inflammatory cells. Intratracheal application of an antagonist of the vanilloid receptor TRPV1 (AMG 9810, 30 mg/kg) prevented enhancement of systolic blood pressure and arrhythmia in vivo, as well as basal and reperfusion-induced myocardial injury ex vivo. Systemic ß1 adrenoreceptor antagonism with metoprolol (10 mg/kg) also blocked enhancement of myocardial oxidative stress and reperfusion injury. CONCLUSIONS: Pulmonary diesel exhaust particulate increases blood pressure and has a profound adverse effect on the myocardium, resulting in tissue damage, but also increases vulnerability to ischemia-associated arrhythmia and reperfusion injury. These effects are mediated through activation of pulmonary TRPV1, the sympathetic nervous system and locally generated oxidative stress.
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Contaminantes Atmosféricos/toxicidad , Daño por Reperfusión Miocárdica/patología , Material Particulado/toxicidad , Receptores Adrenérgicos beta 1/efectos de los fármacos , Canales Catiónicos TRPV/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Animales , Arritmias Cardíacas/inducido químicamente , Arritmias Cardíacas/fisiopatología , Presión Sanguínea/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Inyecciones Espinales , Masculino , Daño por Reperfusión Miocárdica/mortalidad , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , Infiltración Neutrófila/efectos de los fármacos , Ratas , Ratas Wistar , Células Receptoras Sensoriales/efectos de los fármacosRESUMEN
BACKGROUND: Cardiac repair and remodeling following myocardial infarction (MI) is a multifactorial process involving pro-reparative inflammation, angiogenesis and fibrosis. Noninvasive imaging using a radiotracer targeting these processes could be used to elucidate cardiac wound healing mechanisms. The alpha7 nicotinic acetylcholine receptor (É7nAChR) stimulates pro-reparative macrophage activity and angiogenesis, making it a potential imaging biomarker in this context. We investigated this by assessing in vitro cellular expression of É7nAChR, and by using a tritiated version of the PET radiotracer [18F]NS14490 in tissue autoradiography studies. RESULTS: É7nAChR expression in human monocyte-derived macrophages and vascular cells showed the highest relative expression was within macrophages, but only endothelial cells exhibited a proliferation and hypoxia-driven increase in expression. Using a mouse model of inflammatory angiogenesis following sponge implantation, specific binding of [3H]NS14490 increased from 3.6 ± 0.2 µCi/g at day 3 post-implantation to 4.9 ± 0.2 µCi/g at day 7 (n = 4, P < 0.01), followed by a reduction at days 14 and 21. This peak matched the onset of vessel formation, macrophage infiltration and sponge fibrovascular encapsulation. In a rat MI model, specific binding of [3H]NS14490 was low in sham and remote MI myocardium. Specific binding within the infarct increased from day 14 post-MI (33.8 ± 14.1 µCi/g, P ≤ 0.01 versus sham), peaking at day 28 (48.9 ± 5.1 µCi/g, P ≤ 0.0001 versus sham). Histological and proteomic profiling of É7nAChR positive tissue revealed strong associations between É7nAChR and extracellular matrix deposition, and rat cardiac fibroblasts expressed É7nAChR protein under normoxic and hypoxic conditions. CONCLUSION: É7nAChR is highly expressed in human macrophages and showed proliferation and hypoxia-driven expression in human endothelial cells. While NS14490 imaging displays a pattern that coincides with vessel formation, macrophage infiltration and fibrovascular encapsulation in the sponge model, this is not the case in the MI model where the É7nAChR imaging signal was strongly associated with extracellular matrix deposition which could be explained by É7nAChR expression in fibroblasts. Overall, these findings support the involvement of É7nAChR across several processes central to cardiac repair, with fibrosis most closely associated with É7nAChR following MI.
RESUMEN
In obesity, rapidly expanding adipose tissue becomes hypoxic, precipitating inflammation, fibrosis, and insulin resistance. Compensatory angiogenesis may prevent these events. Mice lacking the intracellular glucocorticoid-amplifying enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ßHSD1(-/-)) have "healthier" adipose tissue distribution and resist metabolic disease with diet-induced obesity. Here we show that adipose tissues of 11ßHSD1(-/-) mice exhibit attenuated hypoxia, induction of hypoxia-inducible factor (HIF-1α) activation of the TGF-ß/Smad3/α-smooth muscle actin (α-SMA) signaling pathway, and fibrogenesis despite similar fat accretion with diet-induced obesity. Moreover, augmented 11ßHSD1(-/-) adipose tissue angiogenesis is associated with enhanced peroxisome proliferator-activated receptor γ (PPARγ)-inducible expression of the potent angiogenic factors VEGF-A, apelin, and angiopoietin-like protein 4. Improved adipose angiogenesis and reduced fibrosis provide a novel mechanism whereby suppression of intracellular glucocorticoid regeneration promotes safer fat expansion with weight gain.