A workshop entitled “Muscle regeneration and stem cells: a multiorganismic approach” was organized by Vincent Mouly on behalf of the European Network of Excellence MYORES, from 12-15 October in Niepolomice, Poland. The meeting gathered 32 participants, all post-docs or students, and 12 speakers. The goal of this workshop was to review recent data on muscle regeneration in various animal models, including in humans, and provide information on opportunities and challenges in the clinic.

 

Muscle precursors in Drosophila were presented by K. Jagla (France). J. Morrison (Sweden) then introduced limb regeneration in amphibians, involving satellite cells and M. Daczewska (Poland) spoke about muscle regeneration in the fish. The most recent mouse models were presented by S. Tajbakhsh (France) and J. Beauchamp (UK). P. Zammit (United Kingdom) then gave a review of the markers for skeletal muscle precursors. Molecular signalling was also discussed: SFR by C. Lahoute (France); IGF-1 pathways by T. Nastasi (Italy); myostatin by C. Marcelle (France). Muscle regeneration and precursors in humans were presented by V. Mouly (IdM, France) who spoke about regeneration and D. Furling (IdM, France) who spoke about pathologies. Finally, JT Vilquin (IdM, France) discussed the organization and difficulties of clinical trials.

 

Each participant (student or post-doc) had ten minutes to orally present his/her research project, which generated much discussions and exchanges. It should be noted that this workshop was also open to non-MYORES participants (about 10 were present), including representatives of other European networks (eg TREAT-NMD or MYOAGE). The Institute of Myology was particularly well represented. The atmosphere was friendly and scientific discussions were continuous and fruitful. The comparison of models was particularly informative, showing that the European networks can create interactions between laboratories and / or teams through these workshops.

 

What does this study involve?
This study evaluates a new technique to detect cardiac myopathy. We are seeking to develop a tool to study abnormalities in the strength of cardiac muscle contraction, which are present in many patients with neuromuscular diseases. The main ones are Duchenne and Becker muscular dystrophy, most limb girdle myopathies and certain metabolic myopathies.

 

What is its objective?
The ultimate goal is to detect cardiac defects earlier in order to treat at an early stage, people who do not have heart disease but who are likely to develop it later, in order to improve their prognosis. It should be understood that a cardiac disease develops over many years, between the moment the disease is present in the muscle and when patients have symptoms or severe complications.

Satellite cells reside as quiescent cells underneath the basal lamina that surrounds muscle fibres and respond to damage by producing myoblasts that fuse with myofibres and replenishing the population of satelliite cells. For years, many researchers have suspected that the satellite cell population included muscle stem cells. The identification of a true stem cell has important clinical applications. However, analyzing the specific properties of a single cell is a technically challenging and laborious task. To overcome these obstacles, a team of researchers from the Stanford University School of Medicine led by Dr. Helen Blau has isolated satellite cells from mice genetically engineered to express luciferase. Using a novel non-invasive in vivo bioluminescence imaging technique developed at Stanford they were able to follow their fate after transplantation into normal mice. Transplantation of a single luciferase-expressing muscle stem cell into the muscles of mice led to extensive proliferation which contributes to muscle fibres. Interestingly, some cells also expressed a satellite cell specific marker, Pax-7, indicating self-renewal of the original cell and confirming that it was a stem cell. Furthermore, they show that the dynamics of muscle stem cell behaviour during muscle repair can be followed in a manner not possible using traditional retrospective histological analyses. By imaging luciferase activity, real-time quantitative and kinetic analyses show that donor-derived muscle stem cells proliferate and engraft rapidly after injection until homeostasis is reached. The persistence of stem cell function was demonstrated by inducing repeated cycles of muscle degeneration/regeneration, which generated massive waves of cell proliferation. This is the first study to confirm that satellite cells harbour an exclusive muscle stem cell. Identifying and isolating such a cell in humans would have profound therapeutic implications for disorders such as muscular dystrophy, injury and muscle wasting due to aging, disuse or disease.

Spinal muscular atrophy (SMA) is an inherited genetic disorder caused by a defective gene, SMN1, which fails to produce sufficient amounts of a key protein, called SMN (survival motor neuron), needed for normal motor neuron development. This cellular defect is the underlying basis for the loss of control of muscles in the limbs, neck and chest in these patients. In its most severe form, SMA often leads to death in infancy, and there is currently no treatment or cure. The genetic capability to produce SMN protein is not completely eliminated in SMA patients due to the unique presence of a back-up gene, SMN2. Therefore, drugs that increase SMN protein levels in motor neurons are expected to modulate the severity of the disease. In this new study, researchers detail the identification and characterization of a protein that offers a novel biological mechanism for designing new SMA therapeutics. They found that the substance targets a normal cellular protein, DcpS (human mRNA decapping scavenger enzyme), involved in mRNA metabolism whose inhibition causes increased SMN expression. The finding could help guide the development of the first effective drugs for treating SMA and also lead to second-generation drugs targeting this enzyme. These data provide new insight into the physiological mechanisms that can increase SMN expression and will advance the search for potential treatments.

Founded in 1948, ASHG is the primary professional membership organization for human genetics specialists worldwide, representing nearly 8,000 researchers, academicians, clinicians, genetic counsellors, nurses and others with a special interest in this area. The Society's Annual Meeting is the world's largest gathering of human genetics professionals and a forum for renowned experts in the field.

The ESGCT Annual Congress provides a unique opportunity to interact with all the stakeholders in this dynamic and exciting field at the forefront of biomedical research and clinical development. This year’s Annual Congress includes Plenary and Parallel Sessions on hot topics in the areas of clinical trials, inherited disease, cardiovascular and neurologic disorders, cancer, musculoskeletal disorders, immunity, genetic vaccines, emerging gene transfer technologies and vector manufacturing. Of special interest during this year’s meeting is the growing importance of RNA interference in gene therapy, and stem cell reprogramming for regenerative medicine.
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The symposium is dedicated to the memory of Ketty Schwartz, an outstanding person who has contributed significantly to myocardial science with great enthusiasm and dedication. The programme will include cardiac phenotype and remodelling in cardiopathies, genetics and pathophysiology of cardiac diseases, and therapies of cardiac and skeletal muscle diseases.

This interdisciplinary workshop will bring together scientists from diverse research areas, working on lamins and laminopathies, with a particular focus on newly emerging aspects in lamin function (e.g. stem cell, signalling).

On 5 December at 6:50pm on the France 2 television channel, Julien Clerc, patron of Téléthon 2008 and Thomas, the 8-year old ambassador for patients and their families, will kick off this year’s Téléthon live from Paris.
What is the Téléthon? It’s France pulling together – a vibrant France, as innovative in festivity as in research, a France which stimulates the combat against rare diseases in Europe, a France which believes in the future and is prepared to tackle fate. This year more than ever the Téléthon will be a rendez-vous of festivity, solidarity and combat to change the state of affairs. Together we can take up this exceptional challenge – bringing about the medicine of the future!

A team of researchers led by Anselme Perrier of the Institute of Stem Cells for the Treatment and Study of Monogenic Diseases (Inserm/UEVE UMR861, I-STEM, AFM joint research unit) directed by Marc Peschanski, has just succeeded in performing a first graft of human embryonic stem cells in an animal model for Huntington’s disease. The researchers have thus developed a protocol for transforming these cells into the type of neuron specifically affected in Huntinton’s disease. Following this, they demonstrated that neural progenitors from embryonic stem cells could differentiate themselves into neurons in rat brains presenting lesions similar to those observed in humans.
This work is available online on the PNAS review website. It was in part financed by the AFM (French Muscular Dystrophy Association) thanks to Téléthon donations. 

> Access the complete press release - 2 pages - 145 ko

A new website has been launched called Cure CMD. Cure CMD’s mission is to bring research, treatments and in the future, a cure for Congenital Muscular Dystrophies. Cure CMD will achieve this mission by working globally together with dedicated parent, government and research advocates. By focusing on this mission, Cure CMD will find and fund high potential research and clinical trials. Success will be determined by clinical applications that improve the lives of those afflicted with CMD’s.

When examined carefully at the molecular level, the chromosome turns out to have created its own private world full of tricks, back door exits and novel solutions. This “folly” makes it an untamed innovator. Geneticists have been bewildered for decades. This timely book contains the latest information on the molecular organization of the chromosome. The information is original and is presented in an unorthodox way, while carefully chosen elucidating and attractive figures serve to add clarity to the subject treated. This book will be of particular interest to those in the biotechnological field.

The bimonthly Newsletter of the Institute of Myology keeps you up to date with developments in myology research, and presents a summary of the latest scientific, medical, political and associative news concerning neuromuscular diseases.

You can access our Newsletter by connecting directly to the Institute of Myology website, or by subscribing.

 

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