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AIM: Cardiac diseases remain a leading cause of cardiovascular disease (CVD) related hospitalisation and mortality. That is why research to improve our understanding of pathophysiological processes underlying cardiac diseases is of great importance. There is a strong need for healthy and diseased human cardiac tissue and related clinical data to accomplish this, since currently used animal and in vitro disease models do not fully grasp the pathophysiological processes observed in humans. This design paper describes the initiative of the Netherlands Heart Tissue Bank (NHTB) that aims to boost CVD-related research by providing an open-access biobank. METHODS: The NHTB, founded in June 2020, is a non-profit biobank that collects and stores biomaterial (including but not limited to myocardial tissue and blood samples) and clinical data of individuals with and without previously known cardiac diseases. All individuals aged ≥ 18 years living in the Netherlands are eligible for inclusion as a potential future donor. The stored samples and clinical data will be available upon request for cardiovascular researchers. CONCLUSION: To improve the availability of cardiac tissue for cardiovascular research, the NHTB will include extensive (cardiac) biosamples, medical images, and clinical data of donors with and without a previously known cardiac disease. As such, the NHTB will function as a translational bridge to boost a wide range of cardiac disease-related fundamental and translational studies.

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BACKGROUND: Infections with potentially cardiotropic viruses are associated with the development of atrial fibrillation (AF). However, whether direct viral infection of the atria is involved in the pathogenesis of AF is unclear. We have therefore analysed the presence of cardiotropic viral genomes in AF patients. METHODS: Samples of left atrial tissue were obtained from 50 AF patients (paroxysmal, n = 20; long-standing persistent/permanent, n = 30) during cardiac surgery and from autopsied control patients (n = 14). Herein, the presence of PVB19, EBV, CMV, HHV­6, adenovirus and enterovirus genomes was determined by polymerase chain reaction. The densities of CD45+ and CD3+ cells and fibrosis in the atria were quantified by (immuno)histochemistry. RESULTS: Of the tested viruses only the PVB19 genome was detected in the atria of 10% of patients, paroxysmal AF (2 of 20) and long-standing persistent/permanent AF (3 of 30). Conversely, in 50% of controls (7 of 14) PVB19 genome was found. No significant association was found between PVB19 and CD45+ and CD3+ cells, or between the presence of PVB19 and fibrosis, in either control or AF patients. CONCLUSION: The presence of viral genomes is not increased in the atria of AF patients. These results do not support an important role for viral infection of the atria in the pathogenesis of AF.

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OBJECTIVE: Inflammation of the atria is an important factor in the pathogenesis of atrial fibrillation (AF). Whether the extent of atrial inflammation relates with clinical risk factors of AF, however, is largely unknown. This we have studied comparing patients with paroxysmal and long-standing persistent/permanent AF. METHODS: Left atrial tissue was obtained from 50 AF patients (paroxysmal = 20, long-standing persistent/permanent = 30) that underwent a left atrial ablation procedure either or not in combination with coronary artery bypass grafting and/or valve surgery. Herein, the numbers of CD45+ and CD3+ inflammatory cells were quantified and correlated with the AF risk factors age, gender, diabetes, and blood CRP levels. RESULTS: The numbers of CD45+ and CD3+ cells were significantly higher in the adipose tissue of the atria compared with the myocardium in all AF patients but did not differ between AF subtypes. The numbers of CD45+ and CD3+ cells did not relate significantly to gender or diabetes in any of the AF subtypes. However, the inflammatory infiltrates as well as CK-MB and CRP blood levels increased significantly with increasing age in long-standing persistent/permanent AF and a moderate positive correlation was found between the extent of atrial inflammation and the CRP blood levels in both AF subtypes. CONCLUSION: The extent of left atrial inflammation in AF patients was not related to the AF risk factors, diabetes and gender, but was associated with increasing age in patients with long-standing persistent/permanent AF. This may be indicative for a role of inflammation in the progression to long-standing persistent/permanent AF with increasing age.

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Fibrilación Atrial/fisiopatología , Atrios Cardíacos/fisiopatología , Inflamación/fisiopatología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/cirugía , Ablación por Catéter , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo

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The incidence of heart valve hemangioma is very low and is mostly observed in the mitral and tricuspid valve. In 2006, two cases of aortic valve hemangioma were reported for the first time, including one with calcifying aortic valve stenosis. We now present a case of aortic valve hemangioma in a patient suffering from aortic valve insufficiency combined with atherosclerotic thickening.

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BACKGROUND: Cardiopulmonary bypass during cardiac surgery leads to impaired microcirculatory perfusion. We hypothesized that vascular leakage is an important contributor to microcirculatory dysfunction. Imatinib, a tyrosine kinase inhibitor, has been shown to reduce vascular leakage in septic mice. We investigated whether prevention of vascular leakage using imatinib preserves microcirculatory perfusion and reduces organ injury markers in a rat model of cardiopulmonary bypass. METHODS: Male Wistar rats underwent cardiopulmonary bypass after treatment with imatinib or vehicle (n=8 per group). Cremaster muscle microcirculatory perfusion and quadriceps microvascular oxygen saturation were measured using intravital microscopy and reflectance spectroscopy. Evans Blue extravasation was determined in separate experiments. Organ injury markers were determined in plasma, intestine, kidney, and lungs. RESULTS: The onset of cardiopulmonary bypass decreased the number of perfused microvessels by 40% in the control group [9.4 (8.6-10.6) to 5.7 (4.8-6.2) per microscope field; P<0.001 vs baseline], whereas this reduction was not seen in the imatinib group. In the control group, the number of perfused capillaries remained low throughout the experiment, whilst perfusion remained normal after imatinib administration. Microvascular oxygen saturation was less impaired after imatinib treatment compared with controls. Imatinib reduced vascular leakage and decreased fluid resuscitation compared with control [3 (3-6) vs 12 ml (7-16); P=0.024]. Plasma neutrophil-gelatinase-associated-lipocalin concentrations were reduced by imatinib. CONCLUSIONS: Prevention of endothelial barrier dysfunction using imatinib preserved microcirculatory perfusion and oxygenation during and after cardiopulmonary bypass. Moreover, imatinib-induced protection of endothelial barrier integrity reduced fluid-resuscitation requirements and attenuated renal and pulmonary injury markers.

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Lesión Renal Aguda/prevención & control , Permeabilidad Capilar/efectos de los fármacos , Puente Cardiopulmonar/efectos adversos , Mesilato de Imatinib/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Lesión Renal Aguda/etiología , Lesión Renal Aguda/fisiopatología , Animales , Puente Cardiopulmonar/métodos , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos/métodos , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotelio Vascular/ultraestructura , Mediadores de Inflamación/metabolismo , Masculino , Microcirculación/efectos de los fármacos , Microscopía Electrónica , Consumo de Oxígeno/efectos de los fármacos , Premedicación/métodos , Distribución Aleatoria , Ratas Wistar

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OBJECTIVE: Very little is known about histological aspects of paediatric scars and the possible role of the immune system during their formation. In this study, the histology thoracic scars caused by the placement of an implantable central venous access device in children who underwent treatment for cancer was assessed. METHOD: The amount and type of collagen, the collagen orientation, the type of elastic fibres, the vascularsation, and the count of neutrophils, macrophages, and lymphocytes were analysed. The severity of scarring was assessed using the Vancouver scar scale (VSS). To evaluate the role of the immune system on scar severity and histology, the scars of children suffering from acute lymphoblastic leukaemia (ALL) were compared with the scars of children suffering from other types of childhood cancer. RESULTS: Our results showed an extremely random orientation of the collagen fibres of the paediatric scars with a mean collagen orientation index of 0.22 (standard deviation (SD) 0.10, zero indicating a perfectly random orientation and a perfectly parallel orientation). A lower collagen orientation index was seen in scars with a lower VSS score (VSS score <3: 0.19 versus VSS score ≥3 0.29, p=0.037). A higher total VSS score, resembling a worse scar, was assessed to the scars in the non-ALL group compared with the children with ALL (mean ALL: 0.91 (0-3) versus mean non-ALL: 2.50 (0-6), p=0.037). CONCLUSION: To our knowledge, this is the first study investigating a wide array of histological aspects in paediatric scars. Compared with adult scars, an extremely random collagen orientation was found (0.22 in children versus 0.41 and 0.46 adult normotrophic and hypertrophic scars, respectively). A lower collagen orientation index was found in scars with a lower VSS score. In addition, less severe scarring was measured in children suffering from ALL compared with children suffering from other types of childhood cancer. This suggests that the immune system could play a role in the development of aberrant scarring and should be a target for future research.

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Cicatriz/patología , Colágeno/metabolismo , Tejido Elástico/patología , Linfocitos/patología , Macrófagos/patología , Neovascularización Fisiológica , Neutrófilos/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Adolescente , Recuento de Células , Niño , Preescolar , Cicatriz/complicaciones , Cicatriz/inmunología , Cicatriz/metabolismo , Colágeno Tipo I/metabolismo , Colágeno Tipo II/metabolismo , Estudios Transversales , Femenino , Humanos , Inmunohistoquímica , Linfocitos/inmunología , Macrófagos/inmunología , Masculino , Neoplasias/complicaciones , Neoplasias/inmunología , Neutrófilos/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones

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Autopsy after transcatheter aortic valve implantation (TAVI) is a new field of interest in cardiovascular pathology. To identify the cause of death, it is important to be familiar with specific findings related to the time interval between the procedure and death. We aimed to provide an overview of the autopsy findings in patients with TAVI in their medical history divided by the timing of death with specific interest in the added value of autopsy over a solely clinically determined cause of death. In 8 European centres, 72 cases with autopsy reports were available. Autopsies were divided according to the time interval of death and reports were analysed. In 32 patients who died ≤72 h postprocedure, mortality resulted from cardiogenic or haemorrhagic shock in 62.5 and 34.4%, respectively. In 31 patients with mortality >72 h to ≤30 days, cardiogenic shock was the cause of death in 51.6% followed by sepsis (22.6%) and respiratory failure (9.7%). Of the nine patients with death >30 days, 88.9% died of sepsis, caused by infective endocarditis in half of them. At total of 12 patients revealed cerebrovascular complications. Autopsy revealed unexpected findings in 61.1% and resulted in a partly or completely different cause of death as was clinically determined. Autopsy on patients who underwent TAVI reveals specific patterns of cardiovascular pathology that clearly relate to the time interval between TAVI and death and significantly adds to the clinical diagnosis. Our data support the role of autopsy including investigation of the cerebrum in the quickly evolving era of cardiac device technology.

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Causas de Muerte , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Anciano , Anciano de 80 o más Años , Autopsia , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Tiempo

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Successful stem cell therapy after acute myocardial infarction (AMI) is hindered by lack of engraftment of sufficient stem cells at the site of injury. We designed a novel technique to overcome this problem by assembling stem cell-microbubble complexes, named 'StemBells'. StemBells were assembled through binding of dual-targeted microbubbles (~3µm) to adipose-derived stem cells (ASCs) via a CD90 antibody. StemBells were targeted to the infarct area via an ICAM-1 antibody on the microbubbles. StemBells were characterized microscopically and by flow cytometry. The effect of ultrasound on directing StemBells towards the vessel wall was demonstrated in an in vitro flow model. In a rat AMI-reperfusion model, StemBells or ASCs were injected one week post-infarction. A pilot study demonstrated feasibility of intravenous StemBell injection, resulting in localization in ICAM-1-positive infarct area three hours post-injection. In a functional study five weeks after injection of StemBells cardiac function was significantly improved compared with controls, as monitored by 2D-echocardiography. This functional improvement neither coincided with a reduction in infarct size as determined by histochemical analysis, nor with a change in anti- and pro-inflammatory macrophages. In conclusion, the StemBell technique is a novel and feasible method, able to improve cardiac function post-AMI in rats.

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Microburbujas , Infarto del Miocardio/terapia , Trasplante de Células Madre/métodos , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Administración Intravenosa , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Supervivencia Celular , Células Cultivadas , Modelos Animales de Enfermedad , Ecocardiografía , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Humanos , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Proyectos Piloto , Ratas , Ratas Wistar , Sonicación , Células Madre/citología , Células Madre/metabolismo

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In most pre-clinical animal studies investigating stem cell therapy in acute myocardial infarction (AMI), the administered stem cells are isolated from healthy donors. In clinical practice, however, patients who suffer from AMI will receive autologous cells, for example using adipose-derived stem cells (ASC). During AMI, inflammation is induced and we hypothesized that this might affect characteristics of ASC. To investigate this, ASC were isolated from rat adipose tissue 1 day (1D group, n = 5) or 7 days (7D group, n = 6) post-AMI, and were compared with ASC from healthy control rats (Control group, n = 6) and sham-operated rats (Sham 1D group, n = 5). We found that significantly fewer ASC were present 1 day post-AMI in the stromal vascular fraction (SVF), determined by a colony-forming-unit assay (p < 0.001 vs. Control and 7D). These data were confirmed by flow cytometry, showing fewer CD90-positive cells in SVF of the 1D group. When cultured, no differences were found in proliferation rate and cell size between the groups in the first three passages. Also, no difference in the differentiation capacity of ASC was found. In conclusion, it was shown that significantly fewer stem cells were present in the SVF 1 day post-AMI; however, the stem cells that were present showed no functional differences.

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Tejido Adiposo/citología , Infarto del Miocardio/patología , Células Madre/citología , Animales , Recuento de Células , Diferenciación Celular , Linaje de la Célula , Células Cultivadas , Masculino , Ratas Wistar , Células del Estroma/citología

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Adipose tissue-derived stromal cells (ASC) form a rich source of autologous cells for use in regenerative medicine. In vitro induction of an endothelial phenotype may improve performance of ASCs in cardiovascular repair. Here, we report on an in vitro strategy using direct reprogramming of ASCs by means of ectopic expression of the endothelial-specific transcription factor SRY (sex determining region Y)-box18 (SOX18). SOX18 induces ASCs to express a set of genes involved in vascular patterning: MMP7, KDR, EFNB2, SEMA3G and CXCR4. Accordingly, SOX18 transduced ASCs reorganize under conditions of shear stress, display VEGF-induced chemotaxis and form tubular structures in 3D matrices in an MMP7-dependent manner. These in vitro findings provide insight into molecular and cellular processes downstream of SOX18 and show that reprogramming using SOX18 is sufficient to induce several endothelial-like features in ASCs.

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Tejido Adiposo/citología , Células Endoteliales/metabolismo , Factores de Transcripción SOXF/metabolismo , Células del Estroma/metabolismo , Diferenciación Celular , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Reprogramación Celular , Quimiotaxis/efectos de los fármacos , Células Endoteliales/citología , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Metaloproteinasa 7 de la Matriz/metabolismo , Microtúbulos/química , Microtúbulos/metabolismo , Factores de Transcripción SOXF/genética , Resistencia al Corte , Células del Estroma/citología , Factor A de Crecimiento Endotelial Vascular/farmacología

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Nuclear medicine contributes important tools to support anti-inflammatory drug discovery and development. The support provided is manifold: new molecular entities (NME, either small molecules or biologics) labeled with radioisotopes can be applied in animal models and humans to measure biodistribution, target engagement, and pharmacokinetics. In addition, nuclear imaging techniques can be used to select or enrich the patient populations in clinical trials, to assess disease activity, target status and distribution and to quantify response to therapeutic interventions. In the first part of this review we will outline how nuclear imaging techniques can be applied to support informed decision making in drug development. In the second part, we will briefly high-light the use of nuclear imaging of inflammation in drug development in selected diseases, specifically rheumatoid arthritis (RA), inflammatory bowel diseases (IBD), atherosclerosis and - as an emerging topic - cancer.

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Antiinflamatorios/uso terapéutico , Diseño de Fármacos , Inflamación/diagnóstico por imagen , Inflamación/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud/métodos , Radiofármacos , Tomografía Computarizada de Emisión/métodos , Animales , Humanos , Marcaje Isotópico/métodos , Resultado del Tratamiento

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OBJECTIVES: Irreversible electroporation (IRE) is a new ablation technique that relies on high-voltage electrical pulses. This clinical study evaluates the pathological response of colorectal liver metastases (CRLM) treated with IRE and the clinical safety and feasibility. METHODS: Ten patients with resectable CRLM were included. During laparotomy, the metastases were treated with IRE and resected 60 min later. Safety and feasibility were assessed based on adverse events, laboratory values, technical success and intra-operative ultrasound findings. Tissue response was assessed using triphenyl tetrazolium chloride (TTC) vitality staining and (immuno)histochemical stainings (HE, complement-3d and caspase-3). RESULTS: Ten lesions with a mean diameter of 2.4 cm were successfully electroporated and resected, on average, 84 min later (range 51-153 min). One minor transient cardiac arrhythmia occurred during IRE. Ultrasound showed a sharply demarcated hypoechoic ablation zone around the tumour. TTC showed avitality of all lesions, covering the complete tumour in 8/10 lesions. Although immunohistochemistry proved heterogeneous and difficult to interpret within the tumours, it confirmed irreversible cell damage in the tumour-free margin of all specimens. CONCLUSIONS: This ablate-and-resect study demonstrated avitality caused by IRE of CRLM in humans. Further characterisation of tissue- and tumour-specific electrical properties is warranted to improve ablation protocols for maximised tissue ablation. KEY POINTS: • Irreversible electroporation induces cell death in colorectal liver metastases within 1 h. • The ablation zone shows a sharp demarcation between avital and vital tissue. • Apoptosis is involved in cell death of colorectal liver metastases after IRE. • Effects of IRE can be monitored real-time using intraoperative ultrasound. • Local electrical heterogeneities of tumour tissue may require tumour-specific ablation protocols.

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Técnicas de Ablación/métodos , Neoplasias Colorrectales/cirugía , Electroporación/métodos , Hepatectomía/métodos , Neoplasias Hepáticas/secundario , Cirugía Asistida por Computador/métodos , Anciano , Neoplasias Colorrectales/patología , Estudios de Factibilidad , Femenino , Humanos , Laparotomía , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X

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Nuclear medicine contributes important tools to support antiinflammatory drug discovery and development in many ways. The support provided is manifold: new molecular entities (NME, either small molecules or biologics) labeled with radioisotopes can be applied in animal models and humans to measure biodistribution, target engagement, and pharmacokinetics. In addition, nuclear imaging techniques can be used to select or enrich the patient populations in clinical trials, to assess disease activity, target status and distribution and to quantify response to therapeutic interventions. In the first part of this review we will outline how nuclear imaging techniques can be applied to support informed decision making in drug development. In the second part, we will briefly highlight the use of nuclear imaging of inflammation in drug development in selected diseases, specifically rheumatoid arthritis (RA), inflammatory bowel diseases (IBD), atherosclerosis (ATS) and as an emerging topic cancer.

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The majority of patients survive an acute myocardial infarction (AMI). Their outcome is negatively influenced by post-AMI events, such as loss of viable cardiomyocytes due to a post-AMI inflammatory response, eventually resulting in heart failure and/or death. Recent pre-clinical animal studies indicate that mesenchymal stem cells derived from adipose tissue (ASC) are new promising candidates that may facilitate cardiovascular regeneration in the infarcted myocardium. In this review we have compared all animal studies in which ASC were used as a therapy post-AMI and have focused on aspects that might be important for future successful clinical application of ASC.

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Trasplante de Células Madre Mesenquimatosas/métodos , Infarto del Miocardio/terapia , Tejido Adiposo/citología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Células Madre Mesenquimatosas/fisiología

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BACKGROUND: Ischemia-reperfusion (I/R) models have shown that C-reactive protein (CRP) and immunoglobulin M (IgM) are involved in complement activation. Binding of CRP and IgM to damaged cell membranes initiates complement activation and aggravates I/R injury in various organs. However, the time course of CRP- and IgM-mediated complement activation and the relation to hepatocellular injury and inflammation in liver I/R are unknown. AIM: To evaluate the time course of IgM- and CRP-related complement activation and the relation to hepatocellular injury and inflammation in a hepatic I/R rat model. METHODS: Male Wistar rats were allocated to (1) five groups of animals exposed to 60 min of partial ischemia (70%) induced via clamping of the left segmental portal triad, followed by 0, 3, 6, 12 or 24 h of reperfusion (n = 6 in each group); (2) five groups of sham-operated animals with corresponding reperfusion times (n = 5), and (3) a control group sacrificed before ischemia (n = 5). Hepatocellular injury, inflammatory response, rat plasma CRP and IgM levels and immunohistochemical depositions of CRP, IgM and C3 were assessed for each group. RESULTS: Histopathological injury scores of hematoxylin and eosin sections of ischemic liver lobes demonstrated increasing values throughout the reperfusion time with a peak at 12 h. Plasma aminotransferases (alanine aminotransferase and aspartate aminotransferase) significantly increased after 3 h of reperfusion, peaking at 6 h (3,100 ± 800 U/l; p < 0.05). Hepatic neutrophil influx significantly increased from 3 to 6 h of reperfusion (p < 0.05) and demonstrated the highest value at 12 h (1.1 ± 0.2 U/mg of protein). Plasma IL-6 levels in the ischemia groups showed peak values after 6 h of reperfusion, decreasing significantly thereafter (p < 0.05). Plasma CRP values reached highest levels after 3 h of reperfusion (mean 91 ± 5% of control pool), decreasing significantly thereafter. Rat IgM concentrations in plasma did not significantly change throughout the reperfusion time. Immunohistochemical depositions of IgM, CRP and C3 in ischemic lobes demonstrated a similar pattern in time, reaching maximum values at 12 h of reperfusion. The percentages of depositions of CRP and IgM were significantly correlated [r(S) = 0.569; p < 0.001; Spearman test]. The time course of C3 and CRP depositions throughout reperfusion and C3 and IgM staining were significantly similar [r(S) = 0.797 and r(S) = 0.656, respectively; p < 0.0001; ANOVA]. CONCLUSIONS: CRP and IgM depositions demonstrate a parallel time course throughout the reperfusion to hepatocellular damage, inflammatory response and activated complement deposition in this rat hepatic I/R model. Furthermore, the time course of CRP and IgM depositions was significantly similar to that of activated complement depositions.

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Proteína C-Reactiva/metabolismo , Activación de Complemento , Inmunoglobulina M/sangre , Hígado/inmunología , Hígado/lesiones , Daño por Reperfusión/sangre , Daño por Reperfusión/inmunología , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Hepatocitos/inmunología , Hepatocitos/metabolismo , Hepatocitos/patología , Interleucina-6/sangre , Hígado/patología , Masculino , Neutrófilos/inmunología , Neutrófilos/patología , Ratas , Ratas Wistar

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The Wistar rat is a commonly used strain for experimental animal models. Recently it was shown that results vary between studies using Wistar rats of different suppliers. Therefore we studied whether Wistar rats obtained from Harlan Laboratories (Ha, n=24) and Charles River (CR, n=22) had a different outcome in an acute myocardial infarction (AMI) model. AMI was induced in both Ha and CR Wistar rats by one operator. This resulted in a significantly higher survival rate for Ha (79.2±10.2%) compared with CR rats (54.2±10.2%, p<0.05). Furthermore, CR rats had lost significantly more weight after 7 days (-5.9±3.1%) compared with Ha rats (-0.8±1.7%; p<0.001), indicating a worse health status of the CR rats. Paradoxically, the induced infarct was smaller in CR rats (7.3±3.6% of the heart) compared with Ha rats (12.1±4.7%, p<0.05). This indicates that CR rats were less sensitive for the cardiomyocyte damage subsequent to AMI induction, but remarkably showed more clinical side effects indicating that Wistar rats from two suppliers had a different response within the same AMI model.

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Infarto del Miocardio/veterinaria , Miocitos Cardíacos/ultraestructura , Ratas Wistar/cirugía , Animales , Modelos Animales de Enfermedad , Histocitoquímica , Estimación de Kaplan-Meier , Masculino , Infarto del Miocardio/fisiopatología , Ratas

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Inadequate healing following acute myocardial infarction (AMI) can lead to the development of heart failure. The ischemic myocardium triggers an inflammatory response that clears cell debris and initiates the onset of scar tissue formation. The duration and intensity of this inflammatory response have been linked to the cardiac functioning post-AMI. In order to diminish scar tissue formation and stimulate regeneration of cardiac tissue, mesenchymal stem cell (MSC) have been applied post-AMI and showed beneficial effects on cardiac function. However, other than the expected regeneration of cardiac tissue, modulation of the inflammatory response post-AMI, especially related to an effect on monocytes/macrophages, was recently found to be an important aspect of MSC therapy. In healing post-AMI, monocytes and macrophages are key players that can either stimulate or repress inflammation using different phenotypes. Increased levels of the proinflammatory phenotype have clinically been associated with poor cardiac functional outcome post-AMI. MSC have been suggested to switch the monocytes/macrophages phenotype into a more anti-inflammatory state and might therefore beneficially influence the duration and intensity of the inflammatory response and subsequent cardiac function post-AMI. To gain more insight into this effect of MSC, this review provides an overview of the most relevant studies regarding this modulatory effect of MSC on monocytes/macrophages including its mechanisms to improve cardiac functioning post-AMI.

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Inflamación/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Infarto del Miocardio/terapia , Animales , Cicatriz , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/prevención & control , Humanos , Inflamación/fisiopatología , Macrófagos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Monocitos/metabolismo , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Fenotipo , Factores de Tiempo

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AIMS/HYPOTHESIS: Methylglyoxal (MGO) is a major precursor for advanced glycation end-products (AGEs), which are thought to play a role in vascular complications in diabetes. Known MGO-arginine-derived AGEs are 5-hydro-5-methylimidazolone (MG-H1), argpyrimidine and tetrahydropyrimidine (THP). We studied THP in relation to type 1 diabetes, endothelial dysfunction, low-grade inflammation, vascular complications and atherosclerosis. METHODS: We raised and characterised a monoclonal antibody against MGO-derived THP. We measured plasma THP with a competitive ELISA in two cohort studies: study A (198 individuals with type 1 diabetes and 197 controls); study B (individuals with type 1 diabetes, 175 with normoalbuminuria and 198 with macroalbuminuria [>300 mg/24 h]). We measured plasma markers of endothelial dysfunction and low-grade inflammation, and evaluated the presence of THP and N (ε)-(carboxymethyl)lysine (CML) in atherosclerotic arteries. RESULTS: THP was higher in individuals with type 1 diabetes than in those without (median [interquartile range] 115.5 U/µl [102.4-133.2] and 109.8 U/µl [91.8-122.3], respectively; p = 0.03). THP was associated with plasma soluble vascular cell adhesion molecule 1 in both study A (standardised ß = 0.48 [95% CI 0.38, 0.58]; p < 0.001) and study B (standardised ß = 0.31 [95% CI 0.23, 0.40]; p < 0.001), and with secreted phospholipase A2 (standardised ß = 0.26 [95% CI 0.17, 0.36]; p < 0.001) in study B. We found no association of THP with micro- or macro-vascular complications. Both THP and CML were detected in atherosclerotic arteries. CONCLUSIONS/INTERPRETATION: Our results suggest that MGO-derived THP may reflect endothelial dysfunction among individuals with and without type 1 diabetes, and therefore may potentially play a role in the development of atherosclerosis and vascular disease.

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Aterosclerosis/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/metabolismo , Productos Finales de Glicación Avanzada/sangre , Pirimidinas/sangre , Piruvaldehído/sangre , Molécula 1 de Adhesión Celular Vascular/metabolismo , Adulto , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad

RESUMEN

Adipose tissue-derived stem cells (ASCs) are promising candidates for regenerative therapy, like after myocardial infarction. However, when transplanted into the infarcted heart, ASCs are jeopardized by the ischemic environment. Interestingly, it has been shown that multidrug resistance (MDR) proteins like the breast cancer resistance protein (BCRP) and P-glycoprotein (P-gp) have a protective effect in haematopoietic stem cells. In ASC, however, only expression of BCRP was shown until now. In this study, we therefore analysed the expression and functional activity of BCRP and P-gp and their putative function in ischemia in ASC. BCRP and P-gp protein expression was studied over time (passages 2-6) using western blot analysis and immunohistochemical staining. MDR activity was analysed using protein-specific substrate extrusion assays. Ischemia was induced using metabolic inhibition. All analyses demonstrated protein expression and activity of BCRP in ASCs. In contrast, only minor expression of P-gp was found, without functional activity. BCRP expression was most prominent in early passage ASCs (p2) and decreased during culture. Finally, ischemia induced expression of BCRP. In addition, when BCRP was blocked, a significant increase in dead ASCs was found already after 1 h of ischemia. In conclusion, ASCs expressed BCRP, especially in early passages. In addition, we now show for the first time that BCRP protects ASCs against ischemia-induced cell death. These data therefore indicate that for transplantation of ASCs in an ischemic environment, like myocardial infarction, the optimal stem cell protective effect of BCRP theoretically will be achieved with early culture passages ASCs.

Asunto(s)

Transportadoras de Casetes de Unión a ATP/metabolismo , Tejido Adiposo/metabolismo , Expresión Génica , Proteínas de Neoplasias/metabolismo , Células Madre/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Tejido Adiposo/citología , Adulto , Transporte Biológico/genética , Diferenciación Celular , Hipoxia de la Célula , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Células Cultivadas , Resistencia a Antineoplásicos , Femenino , Humanos , Persona de Mediana Edad , Modelos Biológicos , Proteínas de Neoplasias/genética , Células Madre/citología