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1.
J Diabetes Sci Technol ; : 19322968241242386, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629871

RESUMO

BACKGROUND: There are few studies providing a more comprehensive picture of advanced hybrid closed-loop (AHCL) systems in clinical practice. The aim was to evaluate the effects of the AHCL systems, Tandem® t: slim X2™ with Control IQ™, and MiniMed™ 780G, on glucose control, safety, treatment satisfaction, and practical barriers for individuals with type 1 diabetes. METHOD: One hundred forty-two randomly selected adults with type 1 diabetes at six diabetes outpatient clinics in Sweden at any time treated with either the Tandem Control IQ (TCIQ) or the MiniMed 780G system were included. Glycated hemoglobin A1c (HbA1c) and glucose metrics were evaluated. Treatment satisfaction and practical barriers were examined via questionnaires. RESULTS: Mean age was 42 years, median follow-up was 1.7 years, 58 (40.8%) were females, 65% used the TCIQ system. Glycated hemoglobin A1c was reduced by 0.6% (6.8 mmol/mol; 95% confidence interval [CI] = 0.5-0.8% [5.3-8.2 mmol/mol]; P < .001), from 7.3% to 6.7% (57-50 mmol/mol). Time in range (TIR) increased with 14.5% from 57.0% to 71.5% (95% CI = 12.2%-16.9%; P < .001). Time below range (TBR) (<70 mg/dL, <3.9 mmol/L) decreased from 3.8% to 1.6% (P < .001). The standard deviation of glucose values was reduced from 61 to 51 mg/dL (3.4-2.9 mmol/L, P < .001) and the coefficient of variation from 35% to 33% (P < .001). Treatment satisfaction increased, score 14.8 on the Diabetes Treatment Satisfaction Questionnaire (DTSQ) (change version ranging from -18 to 18, P < .001). Four severe hypoglycemia events were detected and no cases of ketoacidosis. Skin problems were experienced by 32.4% of the study population. CONCLUSIONS: Advanced hybrid closed-loop systems improve glucose control with a reasonable safety profile and high treatment satisfaction. Skin problems are common adverse events.

2.
Front Pediatr ; 10: 932366, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967579

RESUMO

Asthma is the most common chronic respiratory disease in childhood. The long-term goals in managing asthma aim to control symptoms and prevent exacerbations, as well as to reduce side effects of therapy and mortality disease-related. Most of patients have mild to moderate asthma and respond well to standard therapies. However, a minor proportion of children with asthma has severe disease that remains uncontrolled despite optimal adherence to prescribed therapy and treatment of contributory factors, including trigger exposures and comorbidities, which can mimic or worsen asthma and contribute to exacerbations and poor quality of life. Evaluation of comorbidities is fundamental to optimize the management of the disease in a subgroup of patients with poor responder asthma. The overall aim of this article is to describe characteristics of main pediatric severe asthma comorbidities reported in literature, giving clinicians tools to recognize and manage properly these conditions.

3.
Infection ; 50(3): 671-679, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34874541

RESUMO

PURPOSE: To describe the clinical course of COVID-19 in patients with cystic fibrosis (CF) and to identify risk factors for severe COVID-19. METHODS: We conducted a prospective study within the Italian CF Society. CF centers collected baseline and follow-up data of patients with virologically confirmed SARS-CoV-2 infection between March 2020 and June 2021. Odds ratios (ORs) for severe SARS-CoV-2 (as defined by hospital admission) were estimated by logistic regression models. RESULTS: The study included 236 patients with positive molecular test for SARS-CoV-2. Six patients died, 43 patients were admitted to hospital, 4 admitted to intensive care unit. Pancreatic insufficiency was associated with increased risk of severe COVID-19 (OR 4.04, 95% CI 1.52; 10.8). After adjusting for age and pancreatic insufficiency, forced expiratory volume in one second (FEVp) < 40% (OR 4.54, 95% CI 1.56; 13.2), oxygen therapy (OR 12.3, 95% CI 2.91-51.7), underweight (OR 2.92, 95% CI 1.12; 7.57), organ transplantation (OR 7.31, 95% CI 2.59; 20.7), diabetes (OR 2.67, 95% CI 1.23; 5.80) and liver disease (OR 3.67, 95% CI 1.77; 7.59) were associated with increased risk of severe COVID-19, while use of dornase alfa was associated with a reduced risk (OR 0.34, 95% CI 0.13-0.88). No significant changes were observed in FEVp from baseline to a median follow-up of 2 months (median difference: 0, interquartile range: - 4; 5, P = 0.62). CONCLUSION: Clinical features indicative of severe form of CF are associated with increased risk of COVID-19 hospitalization. SARS-CoV-2 infected patients do not experience a deterioration of respiratory function.


Assuntos
COVID-19 , Fibrose Cística , Insuficiência Pancreática Exócrina , COVID-19/epidemiologia , Fibrose Cística/complicações , Insuficiência Pancreática Exócrina/complicações , Humanos , Itália/epidemiologia , Estudos Prospectivos , Fatores de Risco , SARS-CoV-2
4.
Sci Transl Med ; 13(592)2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952677

RESUMO

Host immune responses at the site of Mycobacterium tuberculosis infection can mediate pathogenesis of tuberculosis (TB) and onward transmission of infection. We hypothesized that pathological immune responses would be enriched at the site of host-pathogen interactions modeled by a standardized tuberculin skin test (TST) challenge in patients with active TB compared to those without disease, and interrogated immune responses by genome-wide transcriptional profiling. We show exaggerated interleukin-17A (IL-17A) and T helper 17 (TH17) responses among 48 individuals with active TB compared to 191 with latent TB infection, associated with increased neutrophil recruitment and matrix metalloproteinase-1 expression, both involved in TB pathogenesis. Curative antimicrobial treatment reversed these observed changes. Increased IL-1ß and IL-6 responses to mycobacterial stimulation were evident both in circulating monocytes and in molecular changes at the site of TST in individuals with active TB, supporting a model in which monocyte-derived IL-1ß and IL-6 promote TH17 differentiation within tissues. Modulation of these cytokine pathways may provide a rational strategy for host-directed therapy in active TB.


Assuntos
Interleucina-17/imunologia , Tuberculose Latente , Tuberculose , Humanos , Tuberculose Latente/diagnóstico , Tuberculose Latente/imunologia , Mycobacterium tuberculosis , Tuberculose/tratamento farmacológico , Tuberculose/imunologia
6.
Eur Respir J ; 54(5)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31439682

RESUMO

Information on the clinical traits associated with bronchial neutrophilia in asthma is scant, preventing its recognition and adequate treatment. We aimed to assess the clinical, functional and biological features of neutrophilic asthma and identify possible predictors of bronchial neutrophilia.The inflammatory phenotype of 70 mild-to-severe asthma patients was studied cross-sectionally based on the eosinophilic/neutrophilic counts in their bronchial lamina propria. Patients were classified as neutrophilic or non-neutrophilic. Neutrophilic asthma patients (neutrophil count cut-off: 47.17 neutrophils·mm-2; range: 47.17-198.11 neutrophils·mm-2; median: 94.34 neutrophils·mm-2) were further classified as high (≥94.34 neutrophils·mm-2) or intermediate (47.17- <94.34 neutrophils·mm-2). The effect of smoking ≥10 pack-years was also assessed.Neutrophilic asthma patients (n=38; 36 mixed eosinophilic/neutrophilic) had greater disease severity, functional residual capacity, inhaled corticosteroid (ICS) dose and exacerbations, and lower forced vital capacity (FVC) % pred and forced expiratory volume in 1 s (FEV1) reversibility than non-neutrophilic asthma patients (n=32; 28 eosinophilic and four paucigranulocytic). Neutrophilic asthma patients had similar eosinophil counts, increased bronchial CD8+, interleukin (IL)-17-F+ and IL-22+ cells, and decreased mast cells compared with non-neutrophilic asthma patients. FEV1 and FVC reversibility were independent predictors of bronchial neutrophilia in our cohort. High neutrophilic patients (n=21) had increased serum IgE levels, sensitivity to perennial allergens, exacerbation rate, oral corticosteroid dependence, and CD4+ and IL-17F+ cells in their bronchial mucosa. Excluding smokers revealed increased IL-17A+ and IL-22+ cells in highly neutrophilic patients.We provide new evidence linking the presence of high bronchial neutrophilia in asthma to an adaptive immune response associated with allergy (IgE) and IL-17/22 cytokine expression. High bronchial neutrophilia may discriminate a new endotype of asthma. Further research is warranted on the relationship between bronchoreversibility and bronchial neutrophilia.


Assuntos
Corticosteroides/administração & dosagem , Asma/sangue , Asma/tratamento farmacológico , Imunoglobulina E/sangue , Interleucina-17/imunologia , Interleucinas/imunologia , Neutrófilos , Administração Oral , Adulto , Asma/imunologia , Asma/metabolismo , Estudos Transversais , Feminino , Humanos , Interleucina-17/biossíntese , Interleucinas/biossíntese , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Interleucina 22
7.
Eur J Pharmacol ; 827: 181-188, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29548973

RESUMO

Bradykinin, a pro-inflammatory molecule, and its related peptides have been studied for their effects on acute reactions in upper and lower airways, where they can be synthesised and metabolized after exposure to different stimuli including allergens and viral infection. Bradykinin B1 and B2 receptors are constitutively expressed in the airways on several residential and/or immune cells. Their expression can also be induced by inflammatory mediators, usually associated with eosinophil and neutrophil recruitment, such as IL-4, IL-13, TNF-α, IL-6 and IL-8, via intracellular MAPK and NF-κB signalling. In turn, the latters up-regulate both bradykinin receptors. Bradykinin activates epithelial/endothelial and immune cells, neurons and mesenchymal cells (such as fibroblasts, myofibroblasts and smooth muscle cells), which are implicated in the development of airway chronic inflammation, responsiveness and remodelling (a major feature of severe asthma). This review highlights the role of bradykinin and its receptors in respect to chronic inflammatory response involving eosinophils/neutrophils and to vascular/matrix-related airway remodelling in asthmatic airways. This scenario is especially important for understanding the mechanisms involved in the pathogenesis of eosinophilic and/or neutrophilic asthma and hence their therapeutic approach.


Assuntos
Remodelação das Vias Aéreas , Asma/metabolismo , Asma/patologia , Bradicinina/metabolismo , Animais , Humanos
8.
J Ultrasound Med ; 36(10): 2113-2123, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28543857

RESUMO

OBJECTIVES: Respirophasic variation of inferior vena cava (IVC) size is affected by large variability with spontaneous breathing. This study aims at characterizing the dependence of IVC size on controlled changes in intrathoracic pressure. METHODS: Ten healthy subjects, in supine position, performed controlled isovolumetric respiratory efforts at functional residual capacity, attaining positive (5, 10, and 15 mmHg) and negative (-5, -10, and -15 mmHg) alveolar pressure levels. The isovolumetric constraint implies that equivalent changes are exhibited by alveolar and intrathoracic pressures during respiratory tasks. RESULTS: The IVC cross-sectional area equal to 2.88 ± 0.43 cm2 at baseline (alveolar pressure = 0 mmHg) was progressively decreased by both expiratory and inspiratory efforts of increasing strength, with diaphragmatic efforts producing larger effects than thoracic ones: -55 ± 15% decrease, at +15 mmHg of alveolar pressure (P < .01), -80 ± 33 ± 12% at -15 mmHg diaphragmatic (P < .01), -33 ± 12% at -15 mmHg thoracic. Significant IVC changes in size (P < .01) and pulsatility (P < .05), along with non significant reduction in the response to respiratory efforts, were also observed during the first 30 minutes of supine rest, detecting an increase in vascular filling, and taking place after switching from the standing to the supine position. CONCLUSIONS: This study quantified the dependence of the IVC cross-sectional area on controlled intrathoracic pressure changes and evidenced the stronger influence of diaphragmatic over thoracic activity. Individual variability in thoracic/diaphragmatic respiratory pattern should be considered in the interpretation of the respirophasic modulations of IVC size.


Assuntos
Ecocardiografia/métodos , Respiração , Veias Cavas/anatomia & histologia , Veias Cavas/fisiologia , Adulto , Feminino , Humanos , Masculino , Tamanho do Órgão , Valores de Referência , Veias Cavas/diagnóstico por imagem
9.
J Allergy Clin Immunol ; 140(2): 395-406, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27931975

RESUMO

BACKGROUND: Severe asthma might be associated with overexpression of Th17 cytokines, which induce neutrophil recruitment via neutrophil-mobilizing cytokines in airways. OBJECTIVE: To study IL-17-related cytokines in nasal/bronchial biopsies from controls and mild asthmatics (MAs) to severe asthmatics (SAs) in relation to exacerbation rate. METHODS: Inflammatory cells and IL-17A+, IL-17F+, IL-21+, IL-22+, and IL-23+ cells were examined by immunohistochemistry in cryostat sections of bronchial/nasal biopsies obtained from 33 SAs (21 frequent exacerbators [FEs]), 31 MAs (3 FEs), and 14 controls. IL-17F protein was also measured by ELISA in bronchial/nasal lysates and by immunohistochemistry in bronchial tissue obtained from subjects who died because of fatal asthma. Immunofluorescence/confocal microscopy was used for IL-17F colocalization. RESULTS: Higher number (P < .05) of neutrophils, IL-17A+, IL-17F+, and IL-21+ cells in bronchial biopsies and higher numbers (P < .01) of IL-17F+ and IL-21+ cells in nasal biopsies were observed in SAs compared with MAs. Bronchial IL-17F+ cells correlated with bronchial neutrophils (r = 0.54), exacerbation rate (r = 0.41), and FEV1 (r = -0.46). Nasal IL-17F+ cells correlated with bronchial IL-17F (r = 0.35), exacerbation rate (r = 0.47), and FEV1 (r = -0.61). FEs showed increased number of bronchial neutrophils/eosinophils/CD4+/CD8+ cells and bronchial/nasal IL-17F+ cells. Receiver operating characteristic curve analysis evidenced predictive cutoff values of bronchial neutrophils and nasal/bronchial IL-17F for discriminating between asthmatics and controls, between MAs and SAs and between FEs and non-FEs. IL-17F protein increased in bronchial/nasal lysates of SAs and FEs and in bronchial tissue of fatal asthma. IL-17F colocalized in CD4+/CD8+ cells. CONCLUSIONS: IL-17-related cytokines expression was amplified in bronchial/nasal mucosa of neutrophilic asthma prone to exacerbation, suggesting a pathogenic role of IL-17F in FEs.


Assuntos
Asma/imunologia , Citocinas/imunologia , Mucosa Respiratória/imunologia , Adulto , Idoso , Brônquios/citologia , Brônquios/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infiltração de Neutrófilos , Neutrófilos/imunologia , Nariz/citologia , Nariz/imunologia , Mucosa Respiratória/citologia
11.
Heart Fail Rev ; 20(4): 505-18, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25652330

RESUMO

Apelin is an endogenous peptide acting on the APJ receptor. It consists of several isoforms characterized by different numbers of amino acids. The number of amino acids in the active isoforms range from 36 to 12. Apelin-13 and, to a lesser extent, apelin-36 are considered the most active isoforms with the greatest activity on the cardiovascular homeostasis. The effects normally exerted by the basal level of endogenous apelin can be enhanced not only by its up-regulation, but may also by its exogenous administration. The present review considers the effects of apelin on various aspects of the cardiovascular function, such as cardiac development, vasomotor tone, angiogenesis, myocardial inotropy in healthy and failing hearts as well as the prevention of ischemia-reperfusion injury, cardiac fibrosis and remodeling. Also the biphasic changes in apelin level during the evolution of heart failure are considered. Although the positive inotropic effect exerted by apelin in normal and failing hearts would suggest the use of this peptide in the treatment of heart failure, the limited duration and extent of its effect do not support this possibility, unless a long-lasting (6 h) infusion is performed to overcome the limit of its short life. However, although the data on the characteristics of the inotropic activity do not provide a strong support for the treatment of active heart failure, apelin may be used in the prevention of heart failure because of its activity in limiting the consequences of myocardial ischemia such as infarct size and cardiac remodeling.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Animais , Apelina , Sistema Cardiovascular/metabolismo , Insuficiência Cardíaca/metabolismo , Humanos
12.
Biomaterials ; 35(1): 92-104, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24099712

RESUMO

Despite the enormous progress in the treatment of coronary artery diseases, they remain the most common cause of heart failure in the Western countries. New translational therapeutic approaches explore cardiomyogenic differentiation of various types of stem cells in combination with tissue-engineered scaffolds. In this study we fabricated PHBHV/gelatin constructs mimicking myocardial structural properties. Chemical structure and molecular interaction between material components induced specific properties to the substrate in terms of hydrophilicity degree, porosity and mechanical characteristics. Viability and proliferation assays demonstrated that these constructs allow adhesion and growth of mesenchymal stem cells (MSCs) and cardiac resident non myocytic cells (NMCs). Immunofluorescence analysis demonstrated that stem cells cultured on these constructs adopt a distribution mimicking the three-dimensional cell alignment of myocardium. qPCR and immunofluorescence analyses showed the ability of this construct to direct initial MSC and NMC lineage specification towards cardiomyogenesis: both MSCs and NMCs showed the expression of the cardiac transcription factor GATA-4, fundamental for early cardiac commitment. Moreover NMCs also acquired the expression of the cardiac transcription factors Nkx2.5 and TBX5 and produced sarcomeric proteins. This work may represent a new approach to induce both resident and non-resident stem cells to cardiac commitment in a 3-D structure, without using additional stimuli.


Assuntos
Fenômenos Biomecânicos , Diferenciação Celular , Miocárdio/citologia , Células-Tronco/citologia , Linhagem da Célula , Humanos , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Infravermelho com Transformada de Fourier , Alicerces Teciduais
13.
J Cardiovasc Pharmacol ; 62(6): 567-75, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23921313

RESUMO

Depending on their concentrations, both nitric oxide (NO) and reactive oxygen species (ROS) take part either in myocardial ischemia reperfusion injury or in protection by ischemic and pharmacological preconditioning (Ipre) and postconditioning (Ipost). At the beginning of reperfusion, a transient release of NO is promptly scavenged by ROS to form the highly toxic peroxynitrite, which is responsible for a further increase of ROS through endothelial nitric oxide synthase uncoupling. The protective role of NO has suggested the use of NO donors to mimic Ipre and Ipost. However, NO donors have not always given the expected protection, possibly because they are responsible for the production of different amounts of ROS that depend on the amount of released NO. This review is focused on the role of the balance of NO and ROS in myocardial injury and its prevention by Ipre and Ipost and after the use of NO donors given with or without antioxidant compounds to mimic Ipre and Ipost.


Assuntos
Pós-Condicionamento Isquêmico , Precondicionamento Isquêmico Miocárdico , Traumatismo por Reperfusão Miocárdica/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Vasos Coronários/fisiopatologia , Interações Medicamentosas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Cardíacas/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/terapia , Miocárdio/enzimologia , Miocárdio/metabolismo , Óxido Nítrico/agonistas , Óxido Nítrico/antagonistas & inibidores , Doadores de Óxido Nítrico/efeitos adversos , Doadores de Óxido Nítrico/uso terapêutico , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/antagonistas & inibidores
14.
Stem Cells Dev ; 21(18): 3278-88, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-22582744

RESUMO

The stemness state is characterized by self-renewal and differentiation properties. However, stem cells are not able to preserve these characteristics in long-term culture because of the intrinsic fragility of their phenotype easily undergoing senescence or neoplastic transformation. Furthermore, although isolated from the same original tissue using similar protocols, adult stem cells can display dissimilar phenotypes and important cell clone/species contamination. Finally, the lack of a clear standardization contributes to complicate the comprehension about the stemness condition. In this context, cell lines displaying a particularly stable phenotype must be identified to define one or multiple benchmarks against which other stem cell lines could be reliably assessed. The present paper demonstrates that it is possible to isolate from the rat dental pulp a stem cell line (MUR-1) that does not display neoplastic transformation in long-term culture. MUR-1 cells stably express a broad range of stemness markers and are able to differentiate into adipogenic, osteogenic, chondrogenic, neurogenic, and cardiomyogenic lineages independently of the culture passages. Moreover, serial in vitro passages have not changed their immunophenotype, proliferation capacity, or differentiation potential. The uniqueness of these characteristics candidates MUR-1 as a model to reliably improve the understanding of the mechanisms governing the stem cell fate in the same as well as in other stem cell populations.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Adultas/metabolismo , Diferenciação Celular , Polpa Dentária/citologia , Animais , Técnicas de Cultura de Células , Linhagem da Célula , Proliferação de Células , Transformação Celular Neoplásica , Células Cultivadas , Técnicas de Cocultura , Citometria de Fluxo , Masculino , Fenótipo , Ratos , Ratos Wistar
15.
J Cardiovasc Pharmacol ; 59(3): 241-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22030894

RESUMO

Low concentrations of a hydrophilic nitric oxide donor (NOD) are reported to reduce myocardial reperfusion injury only when combined with a lipophilic antioxidant (AOX) to form a hybrid molecule (HYB). Here we tested whether liposoluble NOD requires to be combined with AOX to be protective. Isolated rat hearts underwent 30 minutes of ischemia and 120 minutes of reperfusion. To induce postconditioning, 1 µM solutions of the following liposoluble compounds were given during the first 20 minutes of reperfusion: NOD with weak (w-NOD) or strong NO-releasing potency (s-NOD); weak HYB built up with w-NOD and a per se ineffective AOX lead; strong HYB built up with s-NOD and the same AOX; mixtures of w-NOD plus AOX or s-NOD plus AOX. A significant reduction of infarct size with improved recovery of cardiac function was obtained only with weak HYB. We suggest that w-NOD requires the synergy with a per se ineffective AOX to protect. The synergy is possible only if the 2 moieties enter the cell simultaneously as a hybrid, but not as a mixture. It seems that strong HYB was ineffective because an excessive intracellular NO release produces a large amount of reactive species, as shown from the increased nitrotyrosine production.


Assuntos
Antioxidantes/farmacologia , Cardiotônicos/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Doadores de Óxido Nítrico/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Cardiotônicos/administração & dosagem , Cardiotônicos/química , Sinergismo Farmacológico , Pós-Condicionamento Isquêmico/métodos , Masculino , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/administração & dosagem , Doadores de Óxido Nítrico/química , Ratos , Ratos Wistar , Tirosina/análogos & derivados , Tirosina/metabolismo
16.
Am J Physiol Heart Circ Physiol ; 300(6): H2308-15, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21378145

RESUMO

We studied whether apelin-13 is cardioprotective against ischemia/reperfusion injury if given as either a pre- or postconditioning mimetic and whether the improved postischemic mechanical recovery induced by apelin-13 depends only on the reduced infarct size or also on a recovery of function of the viable myocardium. We also studied whether nitric oxide (NO) is involved in apelin-induced protection and whether the reported ischemia-induced overexpression of the apelin receptor (APJ) plays a role in cardioprotection. Langendorff-perfused rat hearts underwent 30 min of global ischemia and 120 min of reperfusion. Left ventricular pressure was recorded. Infarct size and lactate dehydrogenase release were determined to evaluate the severity of myocardial injury. Apelin-13 was infused at 0.5 µM concentration for 20 min either before ischemia or in early reperfusion, without and with NO synthase inhibition by N(G)-nitro-l-arginine (l-NNA). In additional experiments, before ischemia also 1 µM apelin-13 was tested. APJ protein level was measured before and after ischemia. Whereas before ischemia apelin-13 (0.5 and 1.0 µM) was ineffective, after ischemia it reduced infarct size from 54 ± 2% to 26 ± 4% of risk area (P < 0.001) and limited the postischemic myocardial contracture (P < 0.001). l-NNA alone increased postischemic myocardial contracture. This increase was attenuated by apelin-13, which, however, was unable to reduce infarct size. Ischemia increased APJ protein level after 15-min perfusion, i.e., after most of reperfusion injury has occurred. Apelin-13 protects the heart only if given after ischemia. In this protection NO plays an important role. Apelin-13 efficiency as postconditioning mimetic cannot be explained by the increased APJ level.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Isquemia Miocárdica/fisiopatologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Animais , Receptores de Apelina , Relação Dose-Resposta a Droga , Coração/efeitos dos fármacos , Coração/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Modelos Animais , Infarto do Miocárdio/fisiopatologia , Óxido Nítrico/fisiologia , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G/fisiologia , Recuperação de Função Fisiológica/fisiologia , Fatores de Tempo , Resultado do Tratamento
17.
Antioxid Redox Signal ; 14(5): 909-22, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20615122

RESUMO

In the heart, a great part of ischaemia and reperfusion injuries occurs mainly during the first minutes of reperfusion. The opening of the mitochondrial permeability transition pores is the end point of the cascade to myocardial damage. Also, oxidative stress contributes to cell death. Postconditioning is a protective maneuver that can be selectively timed at the beginning of reperfusion. It is hypothesized that it acts via the reperfusion injury salvage kinase pathway, which includes nitric oxide-dependent and nitric oxide-independent cascades. Apelin is an endogenous peptide that can protect the heart from reperfusion injury if given at the beginning of reperfusion but not before ischaemia. It is hypothesized that it may trigger the reperfusion injury salvage kinase pathway via a specific apelin receptor. Apelin can also limit the oxidative stress by the activation of superoxide dismutase. Apelin and apelin receptor expression increase early after ischaemia and at the beginning of an ischaemic heart failure. These observations suggest that the endogenous release of the peptide can limit the severity of an infarction and ameliorate myocardial contractility compromised by the appearance of the failure. Due to its protective activities, apelin could be a therapeutic tool if administered with the same catheter used for angioplasty or after the maneuvers aimed at bypassing a coronary occlusion.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Receptores Acoplados a Proteínas G/metabolismo , Animais , Bovinos , Radicais Livres/metabolismo , Humanos , Isquemia/metabolismo , Isquemia/prevenção & controle , Pós-Condicionamento Isquêmico/métodos , Camundongos , Contração Miocárdica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosfotransferases/metabolismo , Ratos , Transdução de Sinais
18.
Basic Res Cardiol ; 105(2): 181-92, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20012872

RESUMO

Brief periods (a few seconds) of cyclic coronary occlusions applied early in reperfusion induce a cardioprotection against infarct size, called postconditioning (PostC) in which B(2)-bradykinin receptors play a pivotal role. Since angiotensin-converting enzyme (ACE) inhibitors reduce degradation of kinins, we studied the effects of PostC on infarct size and postischemic myocardial dysfunction in both normotensive (WKY) and spontaneously hypertensive rats (SHR) acutely or chronically treated with the ACE inhibitor Captopril. Isolated hearts from SHR and WKY rats were subjected to the following protocols: (a) ischemia for 30- and 120-min reperfusion (I/R); (b) I/R + PostC protocol (5-cycles 10-s I/R); (c) pretreatment with Captopril for 4-weeks before to subject the hearts to I/R with or without PostC maneuvers. Some SHR hearts were treated with Captopril during the 20- or 40-min early reperfusion with or without PostC maneuvers. Cardiac function was assessed in vivo with echocardiography. Left ventricular pressure and infarct size were measured ex vivo. Chronic Captopril significantly reduced left ventricular hypertrophy in SHR, and reduced infarct size in both WKY and SHR hearts. PostC maneuvers significantly reduced infarct size in WKY, but not in SHR hearts. Yet, PostC slightly improved postischemic systolic function in untreated SHR. Captopril given in reperfusion was unable to limit I/R injury in SHR hearts. Data show that PostC protection against infarct size is blunted in SHR and that PostC is unable to add its protective effect to those of chronic Captopril, which per se reduces cardiac hypertrophy and heart susceptibility to I/R insult.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Captopril/administração & dosagem , Hipertensão/complicações , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/patologia , Animais , Ecocardiografia , Hipertensão/patologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Técnicas In Vitro , Masculino , Traumatismo por Reperfusão Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
19.
Nutr Metab Cardiovasc Dis ; 19(1): 20-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18455377

RESUMO

BACKGROUND AND AIM: The beneficial effects of exercise in reducing the incidence of cardiovascular diseases are well known. Several studies have demonstrated that forced exercise (FE) could activate a stress response similar to a restrain stress. Previous studies suggest that heart protection to ischemic events would be improved by an omega 3 free fatty acid (omega3-FFA)-enriched diet. Here, we investigate the impact of stressful FE and an omega 3-FFA-enriched diet on cardiac tolerance to ischemic events over one month. METHODS AND RESULTS: Twenty-four Wistar rats were randomly assigned to one of the following protocols: 1) Sedentary (SED) animals who were regularly fed; 2) sedentary animals who were given 1ml/day of fish oil for one month; 3) FE+omega3-FFA rats who were given 1ml/day of fish oil and forced to run on a motorized wheel for 30min every day, both for one month; and 4) FE animals were forced to exercise as group 3 and fed with a regular diet. At the end of the treatments an isolated heart preparation was performed. After a 30min global ischemic event and 2h reperfusion, hearts of sedentary-omega3 animals recovered about 37% of left ventricular developed pressure, whereas FE, omega3+FE and CTRL-SED animals recovered only about 15%, 5% and 8% respectively. Similarly, heart infarct size was significantly lower in sedentary-omega3 animals compared to animals in the three other groups. CONCLUSIONS: Results indicate that one month of treatment with an omega3-FFA-enriched diet improves cardioprotection upon ischemic events, whereas FE leads to a reduced heart tolerance to ischemic events, which cannot be reversed by an omega3-FFA diet.


Assuntos
Dieta , Ácidos Graxos Ômega-3/administração & dosagem , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Esforço Físico/fisiologia , Estresse Fisiológico/fisiologia , Animais , Masculino , Contração Miocárdica , Ratos , Ratos Wistar
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