A proteína miostatina, é um regulador negativo do crescimento muscular e a modulação de sua expressão pode consistir em tratamento para distrofias musculares. Nós estudamos expressão endógena da miostatina no músculos gastrocnêmio e diafragma de 4 modelos murinos de degeneração muscular: os camundongos Dmdmdx, SJL/J, Largemyd e Lama2dy-2J/J. Observamos que a miostatina é menos expressa no músculo gastrocnêmio do que diafragma normal, refletindo um músculo mais sujeito a lesão. Nas quatro linhagens distróficas a miostatina é menos expressa do que em camundongos normais, tanto no músculo gastrocnêmio como diafragma, sem diferença entre os dois. A analise comparativa da degeneração e regeneração muscular mostrou maior correlação da inibição da miostatina com o padrão de degeneração. Nossos resultados sugerem que o processo de degeneração, quando iniciado, e independentemente de seu grau, causa molecular primária, ou músculo afetado, parece atuar de forma similar na inibição da expressão da miostatina, possivelmente como estimulo a regeneração do dano. / Myostatin is a negative regulator of muscle growth, and its inhibition has been considered a therapeutic strategy for muscular dystrophies. We evaluated the endogenous expression of myostatin in the gastrocnemius and diaphragm muscles from 4 mouse dystrophic models including Dmdmdx, SJL/J>, Largemyd and Lama2dy2J/J. In normal mice, we observed that myostatin is less expressed in the gastrocnemius than in the diaphragm, reflecting a muscle most prone to lesions. In the 4 dystrophic models, myostatin expression was reduced, in both gastrocnemius and diaphragm muscles. The comparative analysis of the histopathology of the muscles with the expression of myostatin showed a stronger correlation with the pattern of degeneration then regeneration. Our results suggest that, when started, the process of degeneration of the muscle, independently of the primary molecular defect, or degree, seems to act in a similar pathway leading to the inhibition of the expression of myostatin in the affected muscles, possibly as a stimulus to regeneration of damage.

Im Frühjahr/Sommer 2002 wurde eine Befragung von 51 erwachsenen Patienten im Raum Berlin-Brandenburg mit seltenen Muskelerkrankungen bzw. neuromuskulären Erkrankungen zu verschiedenen Aspekten der medizinischen Versorgung durchgeführt. Angewandte Methoden waren ein standardisierter Fragebogen sowie ein Leitfadeninterview. Vom ersten Arztbesuch bis zur in 59% der Fälle im Krankenhaus erfolgten Diagnosestellung einer Muskelerkrankung vergingen durchschnittlich 4,1 Jahre (Median: 1 Jahr). Es fanden sich eine unzureichende Anamneseerhebung und körperliche Untersuchung sowie eine mangelnde Überweisungsbereitschaft an Neurologen. Eine signifikante Verzögerung erlitten Patienten, die anstelle eines Hausarztes zunächst einen anderen Facharzt als den Neurologen aufgesucht hatten. 43% der Patienten hatten Schwierigkeiten, im Anschluss einen kompetenten Arzt für die Langzeitbetreuung zu finden. Fragen der Vererbbarkeit sowie der respiratorischen und kardialen Komplikationen wurden unzu! reichend besprochen. Im Verlauf erfolgte eine mangelnde Überwachung der respiratorischen sowie kardialen Funktion. Die Verordnung von Physiotherapie und Hilfsmitteln wurde dagegen gut bewertet. Bei 51% der Patienten kam es auch nach der Diagnosestellung zu Krankenhausaufenthalten. 22% der Patienten mussten wegen Komplikationen stationär behandelt werden. Insgesamt zeigten sich Defizite in der medizinischen Versorgung, wie sie z.T. bereits in Expertenstellungnahmen bzw. wenigen anderen Studien berichtet wurden. Für den Bereich der seltenen Erkrankungen gilt eine Spezialambulanz als geeignetes Versorgungsmodell, welches die spezialisierte, multidisziplinäre Betreuung der Patienten sichern soll. Solche Einrichtungen existieren mittlerweile in Deutschland, Outcome-Studien fehlen jedoch bisher. / In spring/summer 2002 a group of 51 adult patients in Berlin-Brandenburg suffering from a muscle or a neuromuscular disease were questioned concerning various aspects of their medical care. The applied methods were a standardized questionnaire and a qualitative interview. The average time between the first consultation of a physician and the establishment of the diagnosis of a muscle disease was 4,1 years (median: 1 year). 59% of the patients received their diagnosis at a hospital. An insufficient history-taking, lacks in the physical examination and a reluctance to refer the patient to a neurologist could be identified. There was a significant delay for those patients who initially consulted a non-neurological specialist instead of a general physician. 43% of the patients had difficulties in finding a qualified physician for the long-time care. The patients were insufficiently informed about the heredity of their disease and about possible respiratory and cardiac complicati! ons. There was a lack in following up the respiratory and cardiac functions of the patients. The prescription of physiotherapy and aids was rated positively by the patients. 51% of the patients had hospital stays also after having their diagnosis. 22% were admitted to hospital due to complications of their disease. In general, deficits in the medical care for these patients were shown, similar to those described in expert opinions or few preview studies. A specialized hospital-based outpatient centre that should ensure the specialized multidisciplinary care for the patients is regarded as the model for the medical care in the area of rare diseases. Similar centres exist in Germany by now, but there are no outcome-studies yet.