RESUMO
Lysyl oxidase (LOX) controls matrix remodeling, a key process that underlies cardiovascular diseases and heart failure; however, a lack of suitable animal models has limited our knowledge with regard to the contribution of LOX to cardiac dysfunction. Here, we assessed the impact of LOX overexpression on ventricular function and cardiac hypertrophy in a transgenic LOX (TgLOX) mouse model with a strong cardiac expression of human LOX. TgLOX mice exhibited high expression of the transgene in cardiomyocytes and cardiofibroblasts, which are associated with enhanced LOX activity and H2O2 production and with cardiofibroblast reprogramming. LOX overexpression promoted an age-associated concentric remodeling of the left ventricle and impaired diastolic function. Furthermore, LOX transgenesis aggravated angiotensin II (Ang II)-induced cardiac hypertrophy and dysfunction, which triggered a greater fibrotic response that was characterized by stronger collagen deposition and cross-linking and high expression of fibrotic markers. In addition, LOX transgenesis increased the Ang II-induced myocardial inflammatory infiltrate, exacerbated expression of proinflammatory markers, and decreased that of cardioprotective factors. Mechanistically, LOX overexpression enhanced oxidative stress and potentiated the Ang II-mediated cardiac activation of p38 MAPK while reducing AMPK activation. Our findings suggest that LOX induces an age-dependent disturbance of diastolic function and aggravates Ang II-induced hypertrophy, which provides novel insights into the role of LOX in cardiac performance.-Galán, M., Varona, S., Guadall, A., Orriols, M., Navas, M., Aguiló, S., de Diego, A., Navarro, M. A., García-Dorado, D., Rodríguez-Sinovas, A., Martínez-González, J., Rodriguez, C. Lysyl oxidase overexpression accelerates cardiac remodeling and aggravates angiotensin II-induced hypertrophy.
Assuntos
Angiotensina II/farmacologia , Cardiomegalia/induzido quimicamente , Regulação Enzimológica da Expressão Gênica/fisiologia , Proteína-Lisina 6-Oxidase/metabolismo , Remodelação Ventricular/fisiologia , Animais , Cardiomegalia/enzimologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Inflamação , Camundongos , Camundongos Transgênicos , Miocárdio/citologia , Proteína-Lisina 6-Oxidase/genética , Transdução de SinaisRESUMO
We investigated the molecular mechanisms involved in the pathogenesis of three inflammatory myopathies, dermatomyositis (DM), polymyositis (PM) and inclusion body myositis (IBM). We performed microarray experiments() using microdissected pathological muscle fibres from 15 patients with these disorders and five controls. Differentially expressed candidate genes were validated by immunohistochemistry on muscle biopsies, and the altered pathways were analysed in human myotube cultures. Up-regulation of genes involved in viral and nucleic acid recognition were found in the three myopathies but not in controls. In DM, retinoic acid-inducible gene 1 (RIG-I, DDX58) and the novel antiviral factor DDX60, which promotes RIG-I-mediated signalling, were significantly up-regulated, followed by IFIH1 (MDA5) and TLR3. Immunohistochemistry confirmed over-expression of RIG-I in pathological muscle fibres in 5/5 DM, 0/5 PM and 0/5 IBM patients, and in 0/5 controls. Stimulation of human myotubes with a ligand of RIG-I produced a significant secretion of interferon-ß (IFNß; p < 0.05) and up-regulation of class I MHC, RIG-I and TLR3 (p < 0.05) by IFNß-dependent and TLR3-independent mechanisms. RIG-I-mediated innate immunity, triggered by a viral or damage signal, plays a significant role in the pathogenesis of DM, but not in that of PM or IBM.
Assuntos
RNA Helicases DEAD-box/metabolismo , Dermatomiosite/metabolismo , Imunidade Inata , Fibras Musculares Esqueléticas/metabolismo , Transdução de Sinais , Adulto , Idoso , Estudos de Casos e Controles , Células Cultivadas , Proteína DEAD-box 58 , RNA Helicases DEAD-box/genética , Dermatomiosite/genética , Dermatomiosite/imunologia , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Estudos de Associação Genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imuno-Histoquímica , Corpos de Inclusão/imunologia , Corpos de Inclusão/metabolismo , Helicase IFIH1 Induzida por Interferon , Interferon beta/metabolismo , Masculino , Microdissecção , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Polimiosite/genética , Polimiosite/imunologia , Polimiosite/metabolismo , Receptores Imunológicos , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismoRESUMO
OBJECTIVE: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a frequent autoimmune neuropathy with a heterogeneous clinical spectrum. Clinical and experimental evidence suggests that autoantibodies may be involved in its pathogenesis, but the target antigens are unknown. Axoglial junction proteins have been proposed as candidate antigens. We examined the reactivity of CIDP patients' sera against neuronal antigens and used immunoprecipitation for antigen unraveling. METHODS: Primary cultures of hippocampal neurons were used to select patients' sera that showed robust reactivity with the cell surface of neurons. The identity of the antigens was established by immunoprecipitation and mass spectrometry, and subsequently confirmed with cell-based assays, immunohistochemistry with teased rat sciatic nerve, and immunoabsorption experiments. RESULTS: Four of 46 sera from patients with CIDP reacted strongly against hippocampal neurons (8.6%) and paranodal structures on peripheral nerve. Two patients' sera precipitated contactin-1 (CNTN1), and 1 precipitated both CNTN1 and contactin-associated protein 1 (CASPR1). Reactivity against CNTN1 was confirmed in 2 cases, whereas the third reacted only when CNTN1 and CASPR1 were cotransfected. No other CIDP patient or any of the 104 controls with other neurological diseases tested positive. All 3 patients shared common clinical features, including advanced age, predominantly motor involvement, aggressive symptom onset, early axonal involvement, and poor response to intravenous immunoglobulin. INTERPRETATION: Antibodies against the CNTN1/CASPR1 complex occur in a subset of patients with CIDP who share common clinical features. The finding of this biomarker may help to explain the symptoms of these patients and the heterogeneous response to therapy in CIDP.
Assuntos
Anticorpos/sangue , Contactina 1/imunologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/sangue , Idoso , Animais , Animais Recém-Nascidos , Anticorpos/farmacologia , Moléculas de Adesão Celular Neuronais/metabolismo , Células Cultivadas , Feminino , Seguimentos , Hipocampo/citologia , Hipocampo/patologia , Humanos , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Condução Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/imunologia , Ratos , Ratos Endogâmicos Lew , Nervo Isquiático/metabolismo , Soro , Estatísticas não Paramétricas , TransfecçãoRESUMO
Pericytes are periendothelial cells that have been involved in many different functions including a possible role as mesodermal stem/progenitor cells. In the present study we demonstrate that alkaline phosphatase (AP) expression is specific for human muscular pericytes and can be used as a marker to identify them in skeletal muscle biopsies. We studied the pericyte population in skeletal muscle biopsies from controls, myopathic and neuropathic patients. We observed a significant increase in the number of pericytes only in myopathies that correlated with the number of NCAM(+) fibres, suggesting that an active muscular degenerative/regenerative process is related to an increase in the pericyte population. AP(+) pericytes sorted from skeletal muscle samples were able to activate the myogenic programme and fuse with both mononucleate satellite cells and mature multinucleated myotubes in vitro, demonstrating that they could participate in muscle regeneration. In accordance, pericytes expressing the myogenic transcription factor MyoD were found in biopsies of myopathic biopsies. All these data support the hypothesis that, apart from satellite cells, pericytes may play an important role in muscle regeneration in adult human muscles in vivo.
Assuntos
Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Distrofias Musculares/patologia , Doenças Neuromusculares/patologia , Pericitos/citologia , Regeneração/fisiologia , Adulto , Biomarcadores , Biópsia , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/fisiologia , Distrofias Musculares/fisiopatologia , Proteína MyoD/metabolismo , Doenças Neuromusculares/fisiopatologia , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/fisiologiaRESUMO
The aim of this article is to map the intellectual structure of scholarship on economic and social value in the sport industry. Given that bibliometric techniques are specially appropriate for identifying the intellectual structures of a field of knowledge and complement traditional literature reviews, a co-citation bibliometric analysis has been applied. This kind of analysis identifies networks of interconnections. Therefore, we aim to detect both the most and the least active research areas in this field, as well as their sub-disciplinary composition. There is an abundance of literature on sport efficiency and economic efficiency in the sport industry, our main conclusion is the identification of a literature gap in regard to social value in sport organisations, which is expected to be a research opportunity for scholars. This is in line with the lack of standardisation in the measurement for social value in sport organisations. In fact, similar to analysis undertaken in the past few decades of other industries with contributions to stakeholders and the multi-fiduciary theory of stakeholders, both the creation of social value indicators for sport entities and the empirical analysis of social efficiency in sport institutions, are identified and outlined as future areas of research. Therefore, this bibliometric analysis will contribute to determine the future challenges that this area of research will face in the following years so as to fill the literature gap identified.
RESUMO
Myasthenia gravis (MG) is an autoimmune disease characterized by the presence of autoantibodies, mainly against the acetylcholine receptor (AChR). The mechanisms triggering and maintaining this chronic disease are unknown. MiRNAs are regulatory molecules that play a key role in the immune system and are altered in many autoimmune diseases. The aim of this study was to evaluate miRNA profiles in serum of 61 AChR MG patients. We studied serum from patients with early onset MG (nâ=â22), late onset MG (nâ=â27) and thymoma (nâ=â12), to identify alterations in the specific subgroups. In a discovery cohort, we analysed 381 miRNA arrays from 5 patients from each subgroup, and 5 healthy controls. The 15 patients had not received any treatment. We found 32 miRNAs in different levels in MG and analysed 8 of these in a validation cohort that included 46 of the MG patients. MiR15b, miR122, miR-140-3p, miR185, miR192, miR20b and miR-885-5p were in lower levels in MG patients than in controls. Our study suggests that different clinical phenotypes in MG share common altered mechanisms in circulating miRNAs, with no additional contribution of the thymoma. MG treatment intervention does not modify the profile of these miRNAs. Novel insights into the pathogenesis of MG can be reached by the analysis of circulating miRNAs since some of these miRNAs have also been found low in MG peripheral mononuclear cells, and have targets with important roles in B cell survival and antibody production.
Assuntos
MicroRNAs/genética , Miastenia Gravis/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Humanos , Imunossupressores/uso terapêutico , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Miastenia Gravis/terapia , Timectomia , Resultado do TratamentoRESUMO
Dysferlinopathies are caused by mutations in the DYSF gene. Dysferlin is a protein mainly expressed in the skeletal muscle and monocytes. Cell therapy constitutes a promising tool for the treatment of muscular dystrophies. The aim of our study was to evaluate the effect of bone marrow transplantation (BMT) using the A/J Dysf(prmd) mouse model of dysferlinopathy. For that purpose, we studied dysferlin expression by western blot and/or immunohistochemistry in transplanted mice and controls. Computerized analyses of locomotion and electrophysiological techniques were also performed to test the functional improvement. We observed dysferlin expression in splenocytes, but not in the skeletal muscle of the transplanted mice. However, the locomotion test, electromyography studies, and muscle histology showed an improvement in all transplanted mice that was more significant in the animals transplanted with dysferlinâº/⺠cells. In conclusion, although BMT restores dysferlin expression in monocytes, but not in skeletal muscle, muscle function was partially recovered. We propose that the slight improvement observed in the functional studies could be related with factors, such as the hepatocyte growth factor, released after BMT that prevented muscle degeneration.
Assuntos
Transplante de Medula Óssea/métodos , Proteínas de Membrana/metabolismo , Distrofia Muscular do Cíngulo dos Membros/fisiopatologia , Distrofia Muscular do Cíngulo dos Membros/cirurgia , Animais , Western Blotting , Modelos Animais de Doenças , Disferlina , Eletromiografia , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos , Camundongos Mutantes , Atividade Motora/genética , Atividade Motora/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Distrofia Muscular do Cíngulo dos Membros/genética , Resultado do TratamentoRESUMO
Objetivo: identificar posibles factores de riesgo para desarrollar lesiones metacrónicas en el cáncer colorrectal, elaborando un índice pronóstico individual del riesgo. Material y métodos: revisamos 382 cánceres colorrectales resecados. Comparamos la diferente incidencia de lesiones metacrónicas en 40 variables referentes al paciente y a las lesiones neoplásicas iniciales. Con aquellas que mostraron diferencias significativas en el análisis estadístico multivariable, elaboramos un índice individual de riesgo, clasificando los pacientes en 3 grupos de riesgo de metacronicidad. Resultados: las variables con valor pronóstico para la metacronicidad fueron: localización distal del cáncer: OR = 2,30 IC 95% (1,03-5,13); consumo de alcohol: OR = 2,20 IC 95% (1,08-4,48); presencia de adenoma sincrónico único: OR = 2,47 IC 95% (1,03- 4,48) o múltiple: OR = 4,26 IC 95% (1,78-10-17) y adenoma avanzado: OR = 2,91 IC 95% (1,52-12,60). La expresión tisular de MUC-5 en el tumor mostró valor protector: OR = 0,23 IC 95% (0,08-0,66). Con estas variables se elaboró un índice pronóstico para el desarrollo de lesiones metacrónicas, clasificando a los individuos en tres grupos de riesgo, con un poder de discriminación de p < 0,000001. El índice mostró una sensibilidad de 75,32%, especificidad = 84,21%, valor predictivo positivo = 75,34%, negativo = 92,31%, con una precisión diagnóstica = 80,75%. Conclusiones: la identificación de variables de riesgo para desarrollar lesiones metacrónicas permitió calcular, desde la cirugía, un índice pronóstico individual, clasificando los pacientes en 3 grupos de riesgo. Los grupos de alto y bajo riesgo registraron una aceptable especificidad y precisión para el pronóstico de lesiones metacrónicas, destacando el elevado poder predictivo negativo de nuestra clasificación, que aconsejaría un diferente seguimiento endoscópico(AU)
Aim: to identify possible risk factors for the development of metachronous lesions in colorectal cancer (CRC) which would allow to establish a post-surgical individual prognostic index. Patients and methods: three hundred eighty-two surgically treated CRC were reviewed. We compared the incidence of metachronous lesions in 40 variables concerning patient clinical data and initial neoplastic findings. An individual risk index for metachronicity was drawn up including those variables which presented significant differences in multivariate logistic regression, dividing patients into three groups. Results: variables with prognostic value for metachronicity were distal cancer location: OR= 2.30 (1.03-5.13), alcohol intake: OR = 2.20 (1.08-4.48), presence of synchronous adenomas: isolated: OR = 2.47 (1.03-4.48), multiple: OR = 4.26 (1.78-10.17), and presence of synchronous advanced adenoma: OR= 2.91 (1.52- 12.60). Tumor MUC-5 expression proved to have a protective role: OR = 0.23 (0.08-0.66). An individual risk score was established considering these variables and patients could be classified into three groups, with a discrimination power for metachronicity of p < 0.0000001. Classification in high and low risk groups had a sensitivity = 75.32%, specificity = 84.21%, positive predictive value = 75.34%, negative predictive value = 92.31% and global diagnostic accuracy = 80.75%. Conclusions: the identification of risk factors for the development of metachronous lesions allow to calculate, at the time of surgical treatment, an individual prognostic index and to classify patients into three different risk groups. In high and low risk groups, both specificity and accuracy were acceptable for the prognosis of metachronous lesions, being remarkable the negative predictive power of our classification, which could become relevant when planning a different endoscopic follow up of these patients(AU)