26 de dezembro de 2014 Izabel GavinhoNotícias

Brasil – omega 3 foi administrado em camundongos com distrofia muscular com 8 meses de idade. Os animais tratados apresentaram redução das citoxinas inflmatórias e fibrosantes, redução da CK e melhora de alguns parâmetros funcionais.

O resumo em inglês pode ser lido abaixo:

(Neuroscience Meeting, 2014) Effects of omega-3 therapy in the cardiomyopathy of the mdx mice, at later stages of the disease

A. F. MAURICIO, J. A. PEREIRA, H. SANTO NETO, M. J. MARQUES – Brazil

Duchenne muscular dystrophy is the most common and severe dystrophynopathy in childhood characterized by absence of dystrophin, with progressive muscle wasting and cardiorespiratory failure. In the absence of dystrophin there is sarcolemma instability, increased calcium influx and myonecrosis. Cardiomyopathy is one of the most frequent causes of death in DMD. In the mdx mice model of DMD, signs of cardiomyopathy are first seen around 9 months of age. We investigated the effects of omega-3 therapy in the mdx cardiomyopathy, at later stages of disease (13 months of age). Mdx mice (8 months of age) received fish oil containing eicosapentaenoic acid and docosahexanoic acid (300mg/kg via gavage, 3 days a week), for 5 months. Control mdx received nujol in an equivalent dose and period. Control mdx showed elevated (3 times) serum levels of CK-MB, an indicator of heart necrosis, compared with normal C57BL/10. Omega-3 reduced CK-MB (119±20 UI in mdx-nujol vs. 86±20 UI in mdx-omega-3). In control mdx, electrocardiogram analysis indicated alterations in the amplitudes of some waves, a decrease in the R/S ratio and a significant increase in the cardiomyopathy index. Omega-3 ameliorated some of these heart functional parameters. No changes in heart fibrosis area were seen in omega-3-mdx, with higher levels of fibrosis in the right ventricule (16±3% in mdx-nujol vs. 13±3% in mdx-omega-3). The levels of TNF-a (proinflammatory cytokine), TGF-b (profibrotic factor) and metaloproteinases(MMP)-9 and MMP-2 were all increased in the heart of control mdx in comparison to normal C57BL/10. Omega-3 significantly reduced the levels of TNF-a (1.5±0.4 in mdx-nujol vs. 1.1±0.03 in mdx-omega-3) and MMP-9 (1.3±0.1 in mdx-nujol vs. 1.1±0.09 in mdx-omega-3), with a tendency to reduce TGF-b (1.9±0.3 in mdx-nujol vs. 1.7±0.4 in mdx-omega-3; p > 0.05, Anova). The present results demonstrate that omega-3 is effective against cardiomyopathy in the mdx mouse, at later stages of the disease, being able to improve functional parameters and to regulate molecular markers (TNF-a, TGF-b and MMPs) of dystrophy progression, therefore deserving future investigation in DMD clinical trials.


Fonte: http://distrofiamuscular.net/principal.htm



26 de dezembro de 2014 Izabel GavinhoNotícias

China – O sulforafano é um produto antixoidante presente em alimentos . Os animais tratdos apresentaram aumento da força e da massa muscular, aumento da caminhada, com redução da CK e da DHL. Além disso os animais apresentaram hipertrofia muscular e cardíaca.

O resumo em inglês pode ser lido abaixo:

(J.Appl.Physiol, 2014) Sulforaphane alleviates muscular dystrophy in mdx mice by activation of Nrf2

Chengcao Sun, Cuili Yang, Ruilin Xue, Shujun Li, Ting Zhang, Lei Pan, Xuejiao Ma, Liang Wang, and Dejia Li – China
Sulforaphane (SFN), one of the most important isothiocyanates in the human diet, is known to have chemo-preventive and antioxidant activities in different tissues via activation of NF-E2-related factor 2 (Nrf2)-mediated induction of antioxidant/phase II enzymes, such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1). However, its effects on muscular dystrophy remain unknown. This work was undertaken to evaluate the effects of SFN on Duchenne muscular dystrophy (DMD). 4-week-old mdx mice were treated with SFN by gavage (2 mg/kg body weight per day for 8 weeks), and our results demonstrated that SFN treatment increased the expression and activity of muscle phase II enzymes NQO1 and HO-1 with Nrf2 dependent manner. SFN significantly increased skeletal muscle mass, muscle force (~30%), running distance (~20%) and GSH/GSSG ratio (~3.2 folds) of mdx mice, and decreased the activities of plasma creatine phosphokinase (CK) (~45%) and lactate dehydrogenase (LDH) (~40%), gastrocnemius hypertrophy (~25%), myocardial hypertrophy (~20%) and MDA levels (~60%). Further, SFN treatment also reduced the central nucleation (~40%), fiber size variability, inflammation and improved the sarcolemmal integrity of mdx mice. Collectively, these results show that SFN can improve muscle function, pathology and protect dystrophic muscle from oxidative damage in mdx mice through Nrf2 signaling pathway, which indicate Nrf2 may represent a new therapeutic target for muscular dystrophy.


Fonte: http://distrofiamuscular.net/principal.htm



26 de dezembro de 2014 Izabel GavinhoNotícias
USA – Os pacientes com distrofia muscular de Duchenne (DMD) normalmente exibem disfunção muscular esquelética cardíaca progressiva e são comumente tratados com corticosteróides para prolongar a deambulação. Fibrose do miocárdio e tratamento com esteróides podem modular a progressão da disfunção cardíaca em pacientes com DMD. Neste estudo os paciente foram acompanhados através da ressonância magnética. Os resultados mostraram que a fibrose cardíaca relaciona-se com o declínio da função cardíaca com o avançar da idade e que o uso de esteróides consegue retardar esta evolução. O resumo em inglês pode ser lido abaixo:
(American Heart Association Meeting, 2014) Myocardial Fibrosis Burden Predicts Left Ventricular Ejection Fraction and is Modified by Age and Steroid Treatment Duration in Duchenne Muscular Dystrophy
Animesh Tandon, Chet R Villa, Kan N Hor, John L Jefferies, Zhiqian Gao, Jeffrey A Towbin, Brenda L Wong, Wojciech Mazur, Robert J Fleck, Joshua J Sticka, Dudley W Benson, and Michael D Taylor – USA
Background: Patients with Duchenne muscular dystrophy (DMD) typically exhibit progressive cardiac and skeletal muscle dysfunction, and are commonly treated with corticosteroids to prolong ambulation. Myocardial fibrosis and steroid treatment may modulate the progression of cardiac dysfunction in DMD patients. We aimed to longitudinally characterize the impact of myocardial fibrosis and steroid treatment on the progression of cardiac dysfunction using cardiac magnetic resonance (CMR) in a large DMD cohort.
Methods: Serial CMR studies performed on DMD patients were reviewed for LVEF and late gadolinium enhancement (LGE) status, a marker for myocardial fibrosis. LVEF was modeled by examining effects of patient age, steroid treatment duration, LGE status, and myocardial fibrosis burden, as assessed by the number of LGE positive (LGE+) LV segments.
Results: We analyzed 469 CMR studies from 99 DMD patients with ≥4 CMRs. Patient age at time of CMR ranged from 6.6 to 29.4 (median 12.3) years. There were 146 (31.1%) LGE+ studies and 59 studies (12.6%) that demonstrated depressed LVEF (LVEF<55%). An age-only model demonstrated that LVEF declined 0.58±0.10%/yr (p<0.0001, r2=0.067). Univariate modeling showed significant associations between LVEF and steroid treatment duration, presence of LGE, and number of LGE+ LV segments; multivariate modeling showed that LVEF declined by 0.93±0.09% for each LGE+ LV segment (p<0.0001, r2=0.171), while age and steroid treatment duration were no longer significant. The number of LGE+ LV segments increased with age by 1.2 segments/year (95% confidence interval 1.1-1.2), and steroid treatment partially mitigated this increase (interaction term β=-0.01±0.005, p=0.010).
Conclusions: Progressive myocardial fibrosis, as imaged by LGE on CMR, is a strong marker for the decline in LVEF in DMD patients. Steroid treatment partially attenuates the age-related increase in myocardial fibrosis burden.


Fonte: http://distrofiamuscular.net/principal.htm


26 de dezembro de 2014 Izabel GavinhoNotícias

Holanda – duas empresas trabalham para desenvolver oligonucleotideos para salto de exon por via injetável (subcutâneo ou intravenoso). Nesta pesquisa os autores administraram oligonucleotideos diretamente no intestino para avaliar a possibilidade de administração oral. Os resultados demonstraram níveis mais baixos com este tratamento em comparação com o uso injetável mas com a associação com caprato de sódio há um aumento da absorção de oligonucleotideos por via intestinal. Em resumo o tratamento por via oral será possível após novos estudos experimentais.

Leia mais sobre o assunto aqui.


Fonte: http://distrofiamuscular.net/principal.htm



26 de dezembro de 2014 Izabel GavinhoNotícias

USA – a empresa Capricor está desenvolvendo um protocolo para tratamento da cardiomiopatia da distrofia muscular de Duchenne com células tronco. A empresa tem experiência no tratamento de outras doenças cardíacas. No Congresso da Associação Americana de Cardiologia eles apresentaram o estudo feito em camundongos com distrofia muscular. Os animais tratados com estas células tronco apresentaram melhora da função cardíaca, redução da fibrose, e recuperação da integridade das mitocôndrias. A cardiomiopatia é a maior causa de mortalidade na doença e este tratamento se mostra viável para controle desta manifestação. 

O resumo em inglês pode ser lido abaixo:

(American Heart Association Meeting, 2014) Heart-derived Cell Therapy for Duchenne Cardiomyopathy: Cardiosphere-derived Cells and their Exosomes Improve Function, Restore Mitochondrial Integrity and Reverse Degenerative Changes in the Hearts of Mdx Mice 
Mark A Aminzadeh, Rachel Tobin, Rachel Smith, Linda Marbán, Eduardo Marbán, Cedars-Sinai Heart Inst, Los Angeles, CA

Abstract
Introduction: Cardiosphere-derived cells (CDCs) promote cardiomyogenesis and angiogenesis, while inhibiting oxidative stress, inflammation and fibrosis, in both ischemic and nonischemic cardiomyopathy. The mdx mouse model of Duchenne muscular dystrophy develops cardiomyopathy due to dystrophin deficiency and the resultant intense oxidative stress, inflammation and apoptosis. Here we tested the hypothesis that transplantation of CDCs or of exosomes derived from CDCs (CDC-XO) may be beneficial in mdx mice.

Methods and Results: A total of 78 mice were studied at a point when global cardiac dysfunction was already evident by echocardiography. Wild-type syngeneic mouse CDCs (105 cells total), CDC-XO (70µg), or vehicle only were injected intramyocardially in 5 left ventricular (LV) sites in 10-month old mdx mice. LV ejection fraction markedly improved over 3 months after treatment either with CDC or CDC-XO compared to vehicle-treated mice (60.4±1.6 vs 48.1±2.2; p<0.005). The functional improvement was associated with enhanced Nrf2 activation, upregulation of Nrf2 downstream gene products, increased expression of mitochondrial transcription factor A and cellular mitochondrial content, restored expression of mitochondrial respiratory chain subunits, reduced collagen I and III deposition, and attenuated infiltration of inflammatory cells [CD68+ macrophages and CD3+ T cells] in the CDC or CDC-XO-treated mouse hearts. Mitochondrial swelling and disorganization of cristae, prominent in vehicle-treated hearts by electron microscopy, were reversed by CDC treatment. Concomitantly, CDC-treated mdx mice exhibited higher maximal exercise capacity compared to vehicle-treated mice over 3 months of follow up (p<0.05). Conclusions: Cardiac function and exercise capacity improved in mdx mice treated with either CDCs or CDC-XO, accompanied by enhanced activation of the antioxidative Nrf2 pathway, attenuation of inflammation, reduction in collagen content and fibrosis, and augmented cardiomyogenesis in CDC-treated mdx hearts. The findings raise the possibility that CDCs and/or CDC-derived exosomes may be useful therapeutically in patients with Duchenne cardiomyopathy.




Fonte: http://distrofiamuscular.net/principal.htm



26 de dezembro de 2014 Izabel GavinhoNotícias

Japão – células tronco pluripotentes induzidas são células adultas que em cultura são transformadas em células tronco equivalentes as células embrionárias. Neste experimento as células adultas com distrofia muscular foram transformadas em células tronco pluirpotentes induzidas e foram subemtidas a terapia para correção do defeito genético por 3 métodos diferentes. Estas células foram injetadas em camundongos que passaram a expressar a proteína distrofina. Todos os métodos foram eficazes indicando ser este um caminho promissor para a terapia das distrofias musculares.

Leia mais sobre o assunto aqui.


Fonte: http://distrofiamuscular.net/principal.htm



31 de outubro de 2014 Izabel GavinhoNotícias

Outras delações não são incluídas.


Estamos revendo no nosso banco de dados para poder listar eventuais candidatos. Caso vocês se deparem com meninos com estas características e que desejem eventualmente participar de estudo clínico por favor nos informe.

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Atenciosamente,

Alexandra Prufer de Queiroz Campos Araujo

Professora Associada de Neuropediatria da UFRJ
email: dra.alexandra.prufer@hotmail.com



31 de outubro de 2014 Izabel GavinhoNotícias

USA – diretrizes são orientações aos profissionais de saúde sobre algum tema; para ser realizada precisa-se de um revisão de todas as informações disponíveis e de uma aprovação por uma comissão de especialistas. Nesta diretriz da Academia Americana de Neurologia para a distrofia muscular tipo cinturas os especialistas recomendam: para os pacientes com suspeita de distrofia muscular, os médicos devem utilizar uma abordagem clínica para orientar o diagnóstico genético baseado no fenótipo clínico, padrão de herança, e manifestações associadas (Nível B). Os médicos devem encaminhar os pacientes recém-diagnosticados com um subtipo de distrofia tipo cinturas alto risco de complicações cardíacas para avaliação cardiológica, mesmo se eles são assintomáticos do ponto de vista cardíaco (Nível B). Em pacientes com alto risco conhecido de insuficiência respiratória, os médicos devem obter prova de função pulmonar periódica (Nível B). Os médicos devem encaminhar os pacientes com distrofia muscular para clínicas que tem acesso a várias especialidades projetadas especificamente para cuidar de pacientes com doenças neuromusculares (Nível B). Os médicos não devem oferecer aos pacientes terapia genética , o transplante de mioblastos, anticorpos neutralizantes da miostatina, ou hormônio de crescimento fora de um estudo de investigação destinada a determinar a eficácia e segurança do tratamento (Nível R). Outras informações podem ser obtidas no site neurology.org


Fonte: http://distrofiamuscular.net/principal.htm



17 de outubro de 2014 Izabel GavinhoNotícias

Mexico – epicatequina é uma substância natural presente no chá verde que tem sido testada em vários modelos experimentais de doença muscular. Neste experimento utilizando camundongos com deficiência de delta sarcoglicano os autores observaram redução do stress oxidativo. O coração e os músculos esqueléticos apresentaram redução da fibrose. Além disso houve melhora da força muscular.

O resumo em inglês pode ser lido abaixo:

(FEBS Journal, 2014) (-)-Epicatechin Improves Mitochondrial Related Protein Levels And Ameliorates Oxidative Stress In Dystrophic Delta Sarcoglycan Null Mouse Striated Muscle

Israel Ramirez-Sanchez, Sergio De los Santos, Silvia Gonzalez-Basurto, Patricia Canto, Patricia Mendoza-Lorenzo, Carlos Palma-Flores, Guillermo Ceballos-Reyes, Francisco Villarreal, Alejandro Zentella-Dehesa and Ramon Coral-Vazquez

Muscular dystrophies (MD) are a group of heterogeneous genetic disorders characterized by progressive striated muscle wasting and degeneration. Although the genetic basis for many of these disorders has been identified, the exact mechanism for disease pathogenesis remains unclear. The presence of oxidative stress (OS) is known to contribute to the pathophysiology and severity of the MD. Mitochondrial dysfunction is observed in MD and likely represents an important determinant of increased OS. Experimental antioxidant therapies have been implemented with the aim of protecting against disease progression, but results from clinical trials have been disappointing. In this study, we explored the capacity of the cacao flavonoid (-)-epicatechin (Epi) to mitigate OS by acting as a positive regulator of mitochondrial structure/function endpoints and redox balance control systems in skeletal and cardiac muscles of dystrophic, δ-sarcoglycan (δ-SG) null mice. Wild type or δ-SG null 2.5 month old male mice were treated via oral gavage with either water (control animals) or Epi (1 mg/kg, twice/day) for 2 weeks. Results evidence a significant normalization of total protein carbonylation, recovery of reduced/oxidized glutathione (GSH/GSSG ratio) and enhanced superoxide dismutase 2, catalase and citrate synthase activities with Epi treatment. These effects were accompanied by increases in protein levels for thiolredoxin, glutathione peroxidase, superoxide dismutase 2, catalase and mitochondrial endpoints. Furthermore, we evidence decreases in heart and skeletal muscle fibrosis, accompanied with an improvement in skeletal muscle function with treatment. These results warrant the further investigation of Epi as a potential therapeutic agent to mitigate MD associated muscle degeneration.


Fonte: http://distrofiamuscular.net/principal.htm



17 de outubro de 2014 Izabel GavinhoNotícias

USA – 13% dos pacientes com distrofia muscular de Duchenne apresentam mutação de ponto. Nestes casos a droga ataluren dada por via oral pode ser útil. Neste artigo são apresentados os resultados de uma pesquisa para determinar a melhor dose da droga administrada por 48 semanas, três vezes ao dia. A droga foi bem tolerada e os meninos que receberam a dose de 10mg/Kg pela manhã, 10mg/Kg a tarde e 20mg/Kg a noite tiveram melhores resultados do que os que tomaram placebo e dos que tomaram doses mais altas da droga. A droga teve uma liberação condicional na Europa para crianças deambulantes com o nome de Translarna.

Leia mais informações aqui.


Fonte: http://distrofiamuscular.net/principal.htm


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