Mutations in the gene encoding the inner nuclear membrane proteins lamins A and C produce cardiac and skeletal muscle dysfunction referred to as Emery Dreifuss muscular dystrophy. Lamins A and C participate in the LINC complex that, along with the nesprin and SUN proteins, LInk the Nucleoskeleton with the Cytoskeleton. Nesprins 1 and 2 are giant spectrin-repeat containing proteins that
Megan J. Puckelwartz; Eric Kessler; Yuan Zhang; Didier Hodzic; K. Natalie Randles; Glenn Morris; Judy U. Earley; Michele Hadhazy; James M. Holaska; Stephanie K. Mewborn; Peter Pytel; Elizabeth M. McNally
Emery-Dreifuss muscular dystrophy (EDMD) is an X-linked inherited disease characterized by early contracture of the elbows, Achilles tendons and post-cervical muscles, slow progressive muscle wasting and weakness and cardiomyopathy presenting with arrhythmia and atrial paralysis: heart block can eventually lead to sudden death. The EDMD gene encodes a novel ubiquitous protein, emerin, which decorates the nuclear rim of many cell
Luca Cartegni; Marina Raffaele; Rita Barresi; Stefano Squarzoni; Patrizia Sabatelli; Nadir Maraldi; Marina Mora; Claudia Di Blasi; Ferdinando Cornelio; Luciano Merlini; Antonello Villa; Fabio Cobianchi; Daniela Toniolo
A screening for mutation in the X-linked Emery–Dreifuss muscular dystrophy (X-EMD) gene was performed among patients affected with severe heart rhythm defects and\\/or dilated cardiomyopathy. Patients were selected from the database of the Department of Cardiology of the University Hospital Brno. One patient presented a mutation in the X-EMD gene and no emerin in his skeletal muscle. The patient had
Stanislav Vohanka; Michal Vytopil; Josef Bednarik; Zdenek Lukas; Zdenek Kadanka; Jiri Schildberger; Roberta Ricotti; Silvia Bione; Daniela Toniolo
Mutations in the gene encoding the inner nuclear membrane proteins lamins A and C produce cardiac and skeletal muscle dysfunction referred to as Emery Dreifuss muscular dystrophy. Lamins A and C participate in the LINC complex that, along with the nesprin and SUN proteins, LInk the Nucleoskeleton with the Cytoskeleton. Nesprins 1 and 2 are giant spectrin-repeat containing proteins that have large and small forms. The nesprins contain a transmembrane anchor that tethers to the nuclear membrane followed by a short domain that resides within the lumen between the inner and outer nuclear membrane. Nesprin's luminal domain binds directly to SUN proteins. We generated mice where the C-terminus of nesprin-1 was deleted. This strategy produced a protein lacking the transmembrane and luminal domains that together are referred to as the KASH domain. Mice homozygous for this mutation exhibit lethality with approximately half dying at or near birth from respiratory failure. Surviving mice display hindlimb weakness and an abnormal gait. With increasing age, kyphoscoliosis, muscle pathology and cardiac conduction defects develop. The protein components of the LINC complex, including mutant nesprin-1alpha, lamin A/C and SUN2, are localized at the nuclear membrane in this model. However, the LINC components do not normally associate since coimmunoprecipitation experiments with SUN2 and nesprin reveal that mutant nesprin-1 protein no longer interacts with SUN2. These findings demonstrate the role of the LINC complex, and nesprin-1, in neuromuscular and cardiac disease. PMID:19008300
Puckelwartz, Megan J; Kessler, Eric; Zhang, Yuan; Hodzic, Didier; Randles, K Natalie; Morris, Glenn; Earley, Judy U; Hadhazy, Michele; Holaska, James M; Mewborn, Stephanie K; Pytel, Peter; McNally, Elizabeth M
Background: Skeletal muscle disorders associated with mutations of lamin A/C gene include autosomal Emery–Dreifuss muscular dystrophy and limb girdle muscular dystrophy 1B. The pathogenic mechanism underlying these diseases is unknown. Recent data suggest an impairment of signalling mechanisms as a possible cause of muscle malfunction. A molecular complex in muscle cells formed by lamin A/C, emerin, and nuclear actin has been identified. The stability of this protein complex appears to be related to phosphorylation mechanisms. Objective: To analyse lamin A/C phosphorylation in control and laminopathic muscle cells. Methods: Lamin A/C N-terminal phosphorylation was determined in cultured mouse myoblasts using a specific antibody. Insulin treatment of serum starved myoblast cultures was carried out to evaluate involvement of insulin signalling in the phosphorylation pathway. Screening of four Emery–Dreifuss and one limb girdle muscular dystrophy 1B cases was undertaken to investigate lamin A/C phosphorylation in both cultured myoblasts and mature muscle fibres. Results: Phosphorylation of lamin A was observed during myoblast differentiation or proliferation, along with reduced lamin A/C phosphorylation in quiescent myoblasts. Lamin A N-terminus phosphorylation was induced by an insulin stimulus, which conversely did not affect lamin C phosphorylation. Lamin A/C was also hyperphosphorylated in mature muscle, mostly in regenerating fibres. Lamin A/C phosphorylation was strikingly reduced in laminopathic myoblasts and muscle fibres, while it was preserved in interstitial fibroblasts. Conclusions: Altered lamin A/C interplay with a muscle specific phosphorylation partner might be involved in the pathogenic mechanism of Emery–Dreifuss muscular dystrophy and limb girdle muscular dystrophy 1B.
Cenni, V; Sabatelli, P; Mattioli, E; Marmiroli, S; Capanni, C; Ognibene, A; Squarzoni, S; Maraldi, N; Bonne, G; Columbaro, M; Merlini, L; Lattanzi, G
The following is a report on a large family with 5 males affected by the X-linked recessive form of Emery-Dreifuss muscular dystrophy with mutation in the STA gene. A detailed longitudinal cardiological evaluation and muscle imaging studies allowed for the assessment of intrafamilial variability of cardiac and muscle involvement. Long term cardiological follow up in the 5 affected males and in 7 female carriers revealed different degrees of severity, ranging from tachycardia-bradycardia syndrome and variable biatrial and left ventricle dilatation, to an episode of isolated symptomatic sustained ventricular tachycardia requiring a device implantation. Muscle imaging in the affected males showed involvement of the soleus and medial head of gastrocnemius on leg muscles and variable involvement on thigh muscles that have not been previously reported. In some cases, imaging showed clear signs of muscle involvement even when no overt signs of weakness could be detected during clinical examination. PMID:21993399
Carboni, Nicola; Mura, Marco; Mercuri, Eugenio; Marrosu, Giovanni; Manzi, Rosa C; Cocco, Eleonora; Nissardi, Vincenzo; Isola, Franco; Mateddu, Anna; Solla, Elisabeta; Maioli, Maria A; Oppo, Valentina; Piras, Rachele; Marini, Stefano; Lai, Carlo; Politano, Luisa; Marrosu, Maria G
We present a case of a 35 year-old male patient with Emery-Dreifuss muscular dystrophy diagnosed in the age of 12 who was assigned to dual chamber pacing system due to bradycardia primarily recognised as sinus node insufficiency with the atrio-ventricular nodal rhythm. During the procedure permanent electrical atrial stand-still without atrial capture were detected and the mode of stimulation was change to VVIR. PMID:23788349
Steckiewicz, Roman; Stolarz, Przemys?aw; Kosior, Dariusz A; Marchel, Micha?; Pieniak, Marian; ?wi?to?, El?bieta; Piotrowska-Kownacka, Ewa; Grabowski, Marcin
Emery–Dreifuss muscular dystrophy (EMD) is an inherited myopathy characterised by muscle contractures, progressive muscle wasting and weakness, with humeroperoneal distribution. Cardiac arrhythmia and heart conduction block are also important characteristics of this disease. The X-linked form of EMD is caused by the absence of emerin, encoded by the STA gene (Xq28). Emerin is normally localised in muscle and other tissues
P Sabatelli; S Squarzoni; S Petrini; C Capanni; A Ognibene; L Cartegni; F Cobianchi; L Merlini; D Toniolo; N. M Maraldi
The patient was a 53-year-old male. He showed steppage gait at the age of 11 and equinus foot at 13. He walked unaided with shoe-insoles to support his heels. Atrial fibrillation and cardiac hypertrophy were found in his 30s, and ventricular tachycardia (VT) was observed at the age of 48. Electrophysiological studies were performed, but VT was not sustained, symptomatic, or showed signs of infra-Hisian block, and a pacemaker was not indicated. At 53, he was introduced to a neurologist because of tetraplegia after the first episode of syncope. A spinal MR showed ossification of posterior longitudinal ligament (OPLL) and central cervical cord injury. Furthermore, he presented not only contracture in his shoulder, elbow, and ankles but also atrophy in his scapulohumeral and gastrocnemius muscles. In accordance with a diagnosis of Emery-Dreifuss muscular dystrophy (EDMD), provocative testing of VT was carried out, and a cardiac resynchronization therapy defibrillator (CRT-D) was implanted. Later, a mutation analysis of the LMNA gene disclosed a known missense mutation of p.Arg377His, and we diagnosed him as EDMD2 (laminopathy). Contractures could be the clue to diagnose EDMD and indicate the need for pacemakers and defibrillators in patients with cardiac conduction disorders. PMID:24990833
Sakiyama, Yoshio; Watanabe, Eri; Otsuka, Mieko; Hirahara, Taishi; Momomura, Shinichi; Hayashi, Yukiko
Background The autosomal dominant form of Emery-Dreifuss muscular dystrophy (AD-EDMD) is caused by mutations in the gene encoding for the lamins A and C (LMNA). Lamins are intermediate filament proteins which form the nuclear lamina underlying the inner nuclear membrane. We have studied the expression and the localization of nuclear envelope proteins in three different cell types and muscle tissue of an AD-EDMD patient carrying a point mutation R377H in the lamin A/C gene. Results Lymphoblastoid cells, skin fibroblasts, primary myoblasts and muscle thin sections were studied by immunocytochemistry and electron microscopy. Cellular levels of A-type lamins were reduced compared to control cells. In contrast, the amount of emerin and lamin B appeared unaltered. Cell synchronization experiments showed that the reduction of the cellular level of A-type lamin was due to instability of lamin A. By electron microscopy, we identified a proportion of nuclei with morphological alterations in lymphoblastoid cells, fibroblasts and mature muscle fibres. Immunofluorescence microscopy showed that a major population of the lamin B receptor (LBR), an inner nuclear membrane protein, was recovered in the cytoplasm in association with the ER. In addition, the intranuclear organization of the active form of RNA polymerase II was markedly different in cells of this AD-EDMD patient. This aberrant intranuclear distribution was specifically observed in muscle cells where the pathology of EDMD predominates. Conclusions From our results we conclude: Firstly, that structural alterations of the nuclei which are found only in a minor fraction of lymphoblastoid cells and mature muscle fibres are not sufficient to explain the clinical pathology of EDMD; Secondly, that wild type lamin A is required not only for the retention of LBR in the inner nuclear membrane but also for a correct localization of the transcriptionally active RNA pol II in muscle cells. We speculate that a rearrangement of the internal chromatin could lead to muscle-specific disease symptoms by interference with proper mRNA transcription.
Reichart, Beate; Klafke, Ruth; Dreger, Christine; Kruger, Eleonora; Motsch, Isabell; Ewald, Andrea; Schafer, Jochen; Reichmann, Heinz; Muller, Clemens R; Dabauvalle, Marie-Christine
Background Autosomal Emery-Dreifuss muscular dystrophy is caused by mutations in the lamin A/C gene (LMNA) encoding A-type nuclear lamins, intermediate filament proteins of the nuclear envelope. Classically, the disease manifests as scapulo-humeroperoneal muscle wasting and weakness, early joint contractures and dilated cardiomyopathy with conduction block; however, move variable skeletal muscle involvement can be present. Previously, we demonstrated increased activity of extracellular signal-regulated kinase (ERK) 1/2 in hearts of LmnaH222P/H222P mice, a model of autosomal Emery-Dreifuss muscular dystrophy, and that blocking its activation improved cardiac function. We therefore examined the role of ERK1/2 activity in skeletal muscle pathology. Methods Sections of skeletal muscle from LmnaH222P/H222P mice were stained with hematoxylin and eosin and histological analysis performed using light microscopy. ERK1/2 activity was assessed in mouse tissue and cultured cells by immunoblotting and real-time polymerase chain reaction to measure expression of downstream target genes. LmnaH222P/H222P mice were treated with selumetinib, which blocks mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1/2 that activates ERK1/2, from 16 to 20 weeks of age to assess the effects of treatment on muscle histology, ERK1/2 activity and limb grip strength. Results We detected enhanced activation of ERK1/2 in skeletal muscle of LmnaH222P/H222P mice. Treatment with selumetinib ameliorated skeletal muscle histopathology and reduced serum creatine phosphokinase and aspartate aminotransferase activities. Selumetinib treatment also improved muscle function as assessed by in vivo grip strength testing. Conclusions Our results show that ERK1/2 plays a role in the development of skeletal muscle pathology in LmnaH222/H222P mice. They further provide the first evidence that a small molecule drug may be beneficial for skeletal muscle in autosomal Emery-Dreifuss muscular dystrophy.
... muscles used for movement (skeletal muscles) and heart (cardiac) muscle. Among the earliest features of this disorder are ... essential for the normal function of skeletal and cardiac muscle. Most EMD gene mutations prevent the production of ...
... by the fact that muscle weakness begins in infancy or very early childhood (typically before age 2). ... lack of muscle tone) and weakness early in infancy associated with delayed milestones. Children usually don’t ...
Muscular dystrophies (MD) are a clinically and genetically heterogeneous disease group. In the last few years, remarkable progress has been made in understanding the close und various relations between skeletal muscle disease and heart muscle disease. Cardiac involvement has been documented in a number of primary MDs and is even the dominant feature in some of them. The myocardium can be affected in the form of a dilated cardiomyopathy while the conduction system can be affected resulting in arrhythmias and conduction defects. Many patients with MD die because of cardiac complications like sudden cardiac death or congestive heart failure. Detailed clinical data about cardiac involvement are available for Duchenne/Becker MD, Emery-Dreifuss MD, myotonic dystrophy, and the different limb girdle MDs. Cardiac manifestations were also found in congenital MD, central core disease, proximal myotonic myopathy, and nemaline myopathy. No data about cardiac abnormalities are available in oculopharyngeal MD and rippling muscle disease. The heart of patients with primary MD should be carefully investigated because of the life-threatening events caused by cardiac complications. There is a strong need for a close collaboration between neurologists and cardiologists in order to provide optimal disease management for the affected patients. PMID:15868359
Perrot, A; Spuler, S; Geier, C; Dietz, R; Osterziel, K J
Mutations in the lamin A/C gene determine a heterogeneous group of congenital diseases, termed laminopathies, consisting of more than 15 phenotypes, including autosomal dominant Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy type 1B. Early onset in infancy has been described in these muscular dystrophies. Reported here is a 7-year-old male with congenital muscular dystrophy. Remarkably, muscle weakness and wasting affected predominantly axial muscles as well as proximal upper and distal lower extremities. The patient rapidly developed joint contractures and spine rigidity with the head only mildly flexed. Serum creatine kinase was moderately elevated. Muscle biopsy indicated a dystrophic pattern with normal immunochemical findings. A novel, de novo missense substitution p.Asn39Tyr within the lamin A/C gene confirmed the diagnosis of a laminopathy. This report broadens the spectrum of lamin A/C gene mutations and illustrates the phenotypic variability of laminopathies with early onset congenital muscular dystrophy. Mutations in the lamin A/C gene should be sought in any infant with dystrophic features and normal tissue immunochemical studies; especially in the presence of moderately elevated serum creatine kinase, predominant axial and humeroperoneal weakness, spine rigidity, and joint contractures. PMID:20837309
Prigogine, Cynthia; Richard, Pascale; Van den Bergh, Peter; Groswasser, José; Deconinck, Nicolas
Emery-Dreifuss muscular dystrophy is a rare disorder characterized by childhood onset of contractures, humeroperoneal muscle atrophy, and cardiac conduction abnormalities. This report presents the cases of two brothers with this dystrophy in whom bilateral hypomyelination of the deep periatrial white matter was noted. In the hypomyelinated regions, a prominent peak centered at 1.5 parts per million was present on short-TE MR spectra likely representing prominence of proteolipids in the macromolecular region. Major peaks (N-acetyl-aspartate, creatine, choline, and myoinositol) were normal. With respect to muscle changes, atrophy of the medial head of the gastrocnemius muscle was noted at MR imaging, and phosphorus spectroscopy of this muscle revealed decreased phosphocreatine and inorganic phosphate peaks. PMID:15569760
Semnic, Robert; Vucurevic, Goran; Kozic, Dusko; Koprivsek, Katarina; Ostojic, Jelena; Sener, Rifat Nuri
Limb-girdle muscular dystrophies constitute a broad range of clinical and genetic entities. We have evaluated 38 autosomal recessive limb-girdle muscular dystrophy (LGMD2) families by linkage analysis for the known loci of LGMD2A-F and protein studies using immunofluorescence and western blotting of the sarcoglycan complex. One index case in each family was investigated thoroughly. The age of onset and the current ages were between 11/2 and 15 years and 6 and 36 years, respectively. The classification of families was as follows: calpainopathy 7, dysferlinopathy 3, ? sarcoglycan deficiency 2, ? sarcoglycan deficiency 7, ? sarcoglycan deficiency 5, ? sarcoglycan deficiency 1, and merosinopathy 2. There were two families showing an Emery-Dreifuss phenotype and nine showing no linkage to the LGMD2A-F loci, and they had preserved sarcoglycans.?? sarcoglycan deficiency seems to be the most severe group as a whole, whereas dysferlinopathy is the mildest. Interfamilial variation was not uncommon. Cardiomyopathy was not present in any of the families. In sarcoglycan deficiencies, sarcoglycans other than the primary ones may also be considerably reduced; however, this may not be reflected in the phenotype. Many cases of primary ? sarcoglycan deficiency showed normal or only mildly abnormal ? sarcoglycan staining.???Keywords: limb-girdle muscular dystrophy; genetic linkage analysis; sarcolemmal complex proteins
Dincer, P.; Akcoren, Z.; Demir, E.; Richard, I.; Sancak, O.; Kale, G.; Ozme, S.; Karaduman, A.; Tan, E.; Urtizberea, J; Beckmann, J.; Topaloglu, H.
The congenital muscular dystrophies are a heterogeneous group of disorders in which weakness and dystrophic pattern on muscle biopsy are present at birth or during the first months of life. This chapter reviews the most common forms of congenital muscular dystrophies, including laminin ?-2 (merosin) deficiency, Ullrich congenital muscular dystrophy, fukutin-related proteinopathy, rigid spine syndrome, and glycosylation disorders of ?-dystroglycan. The latter group is often associated with neuronal migration defects including lissencephaly, pachygyria, cerebellar and brainstem abnormalities, and variable ocular anomalies. Typical clinical findings and underlying genetic defects are discussed to assist in the differential diagnosis and diagnostic work-up of patients with congenital muscular dystrophies. There are still no curative treatment options for patients with congenital muscular dystrophies but regular follow-up and symptomatic care by a multidisciplinary team considering the peculiarities of each disorder are important to maintain or improve patients' quality of life. PMID:23622361
X-linked Emery-Dreifuss muscular dystrophy is caused by loss of function of emerin, an integral protein of the inner nuclear membrane. Yet emerin null mice are essentially normal, suggesting the existence of a critical compensating factor. We show that the lamina-associated polypeptide1 (LAP1) interacts with emerin. Conditional deletion of LAP1 from striated muscle causes muscular dystrophy; this pathology is worsened in the absence of emerin. LAP1 levels are significantly higher in mouse than human skeletal muscle, and reducing LAP1 by approximately half in mice also induces muscle abnormalities in emerin null mice. Conditional deletion of LAP1 from hepatocytes yields mice that exhibit normal liver function and are indistinguishable from littermate controls. These results establish that LAP1 interacts physically and functionally with emerin and plays an essential and selective role in skeletal muscle maintenance. They also highlight how dissecting differences between mouse and human phenotypes can provide fundamental insights into disease mechanisms. PMID:24055652
Shin, Ji-Yeon; Méndez-López, Iván; Wang, Yuexia; Hays, Arthur P; Tanji, Kurenai; Lefkowitch, Jay H; Schulze, P Christian; Worman, Howard J; Dauer, William T
With advances in the genetics of muscle disease, the term, muscular dystrophy, has expanded to include mutations in an increasing large list of genes. This review discusses the genetics, pathophysiology, and potential treatments of the most common forms of muscular dystrophy: Duchenne muscular dystrophy, Becker muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy. Other forms of muscular dystrophy and other genetic muscle disorders are also discussed to provide an overview of this complex clinical problem. PMID:24176421
Shieh, Perry B
The muscular dystrophies comprise a heterogeneous group of genetic disorders that produce progressive skeletal muscle weakness and wasting. There has been rapid growth and change in our understanding of these disorders in recent years, and advances in basic science are being translated into increasing numbers of clinical trials. This review will discuss therapeutic developments in 3 of the most common forms of muscular dystrophy: Duchenne muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy. Each of these disorders represents a different class of genetic disease (monogenic, epigenetic, and repeat expansion disorders), and the approach to therapy addresses the diverse and complex molecular mechanisms involved in these diseases. The large number of novel pharmacologic agents in development with good biologic rationale and strong proof of concept suggests there will be an improved quality of life for individuals with muscular dystrophy.
Leung, Doris G; Wagner, Kathryn R
Facioscapulohumeral muscular dystrophy (FSHD) is a progressive myopathy with a relatively late age of onset (usually in the late teens) compared with Duchenne and many other muscular dystrophies. The current FSHD disease model postulates that contraction of the D4Z4 array at chromosome 4q35 leads to a more open chromatin conformation in that region and allows transcription of the DUX4 gene. DUX4 mRNA is stable only when transcribed from certain haplotypes that contain a polyadenylation signal. DUX4 protein is hypothesized to cause FSHD by mediating cytotoxicity and impairing skeletal muscle differentiation. We recently showed in a cell culture model that DUX4 expression is regulated by telomere length, suggesting that telomere shortening during aging may be partially responsible for the delayed onset and progressive nature of FSHD. We here put our data in the context of other recent findings arguing that progressive telomere shortening may play a critical role in FSHD but is not the whole story and that the current disease model needs additional refinement.
Stadler, Guido; King, Oliver D; Robin, Jerome D; Shay, Jerry W; Wright, Woodring E
Summary The medical entity “muscular dystrophy” has been the object of a recent opinion campaign aimed at promoting a law in favour of euthanasia. This disease has become, in the eyes of the public, a media model of a particularly severe and incurable disease. This very widespread statement does not correspond to reality as far as concerns the life of these patients, to the condition that they have benefited from a very useful and fully provided empirical treatment. As already seen, the hope for life has already doubled, without clear limits. The idea of inducing an interruption when at death’s door, as long as a systematic prevention prior to birth, does not conform with the motivated opinion of the majority of patients consulted. On the contrary, the dogma of incurability may lead to dramatic individual consequences which should be stressed, from a medical viewpoint, on account of the unacceptable risks of social injustice or eugenics that this would imply.
Rideau, Y; Rideau, F
Alternative splicing of pre-mRNAs is a major contributor to proteomic diversity and to the control of gene expression in higher eukaryotic cells. For this reasons, alternative splicing is tightly regulated in different tissues and developmental stages and its disruption can lead to a wide range of human disorders. The aim of this review is to focus on the relevance of alternative splicing for muscle function and muscle disease. We begin by giving a brief overview of alternative splicing, muscle-specific gene expression and muscular dystrophy. Next, to illustrate these concepts we focus on two muscular dystrophy, myotonic muscular dystrophy and facioscapulohumeral muscular dystrophy, both associated to disruption of splicing regulation in muscle.
Pistoni, Mariaelena; Ghigna, Claudia; Gabellini, Davide
Platelets which have complex membranes and calcium shifts similar to those in muscles were investigated in 14 patients with muscular dystrophy and 20 suitable controls. In 4 Duchenne and one limb-girdle dystrophy aggregations were done and found to be depressed with adrenaline and ADP. Electron microscopic and chemical examinations revealed an increased number of dense bodies, changed permeability and/or binding of cations and elevated intracellular calcium in all the 9 cases of Duchenne dystrophy while the 2 limb-girdle and 3 myotonic dystrophies varied. A two phase polymer separation system applied to fixed platelets of all patients and controls showed no abnormality of surface negative charge. PMID:6308847
Yarom, R; Meyer, S; More, R; Liebergall, M; Eldor, A
A 3-year-old, male Labrador retriever dog was presented with clinical signs of progressive exercise intolerance, bilateral elbow extension, rigidity of the forelimbs, hindlimb flexion and kyphosis. Microscopical examination of muscle tissue showed marked variability in myofibre size, replacement of muscle with mature adipose tissue and degeneration/regeneration of muscle fibres, consistent with muscular dystrophy. Immunohistochemical examination for dystrophin showed markedly reduced labelling with monoclonal antibodies specific for the rod domain and the carboxy-terminal of dystrophin, while expression of ?-sarcoglycan, ?-sarcoglycan and ?-dystroglycan was normal. Immunoblotting revealed a truncated dystrophin protein of approximately 135 kDa. These findings supported a diagnosis of congenital canine muscular dystrophy resembling Becker muscular dystrophy in man. PMID:24529507
Baroncelli, A B; Abellonio, F; Pagano, T B; Esposito, I; Peirone, B; Papparella, S; Paciello, O
Muscular dystrophy is a group of more than 30 different clinical genetic disorders that are characterized by progressive skeletal muscle wasting and degeneration. Primary deficiency of specific extracellular matrix, sarcoplasmic, cytoskeletal, or nuclear membrane protein results in several secondary changes such as sarcolemmal instability, calcium influx, fiber necrosis, oxidative stress, inflammatory response, breakdown of extracellular matrix, and eventually fibrosis which leads to loss of ambulance and cardiac and respiratory failure. A number of molecular processes have now been identified which hasten disease progression in human patients and animal models of muscular dystrophy. Accumulating evidence further suggests that aberrant activation of several signaling pathways aggravate pathological cascades in dystrophic muscle. Although replacement of defective gene with wild-type is paramount to cure, management of secondary pathological changes has enormous potential to improving the quality of life and extending lifespan of muscular dystrophy patients. In this article, we have reviewed major cellular and molecular mechanisms leading to muscle wasting in muscular dystrophy. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting. PMID:23669245
Shin, Jonghyun; Tajrishi, Marjan M; Ogura, Yuji; Kumar, Ashok
DDBJ\\/EMBL\\/GenBank accession nos AF036365-AF036367 The dystrophin-glycoprotein complex (DGC) serves as a link between cytoplasmic actin, the membrane and the extracellular matrix of striated muscle. Genetic defects in genes encoding a subset of DGC proteins result in muscular dystrophy and a secondary decrease in other DGC proteins. Caveolae are dynamic structures that have been implicated in a number of functions including
Elizabeth M. McNally; Eloisa de Sá Moreira; David J. Duggan; Carsten G. Bönnemann; Michael P. Lisanti; Hart G. W. Lidov; Mariz Vainzof; M. Rita Passos-Bueno; Eric P. Hoffman; Mayana Zatz; Louis M. Kunkel
... 1 in 20,000 people. What are the genetic changes related to facioscapulohumeral muscular dystrophy? Facioscapulohumeral muscular ... Center . Where can I find general information about genetic conditions? The Handbook provides basic information about genetics ...
A 5-year old girl with Ullrich's atonic-sclerotic muscular dystrophy is reported and 16 previously reported cases are reviewed. The clinical features, in particular proximal contractures, distal hyperextensibility, mild dysmorphism and hyperhidrosis, allow recognition of this subtype of congenital muscular dystrophy, which has no specific pathological characteristics. There is evidence in favour of an autosomal recessive mode of inheritance.
L. De Paillette; J. Aicardi; F. Goutières
The aim of this study was to assess diaphragm electrical activation and diaphragm strength in patients with advanced Duchenne muscular dystrophy during resting conditions. Eight patients with advanced Duchenne muscular dystrophy (age of 25±2 years) were studied during tidal breathing, maximal inspiratory capacity, maximal sniff inhalations, and magnetic stimulation of the phrenic nerves. Six patients were prescribed home mechanical ventilation
Jennifer Beck; Jan Weinberg; Carl-Hugo Hamnegård; Jadranka Spahija; Jan Olofson; Gunnar Grimby; Christer Sinderby
We report, for the first time, on a female Becker muscular dystrophy (BMD) patient with homozygous dystrophin deletion. The 14-year-old patient, product of consanguineous parents, presented with a 7-year history of exercise intolerance and recurrent myoglobinuria. Although CK was elevated to 1,800 U/L, no muscle weakness, atrophy, or hypertrophy was seen on examination. Muscle pathology demonstrated a minimal dystrophic change and faint dystrophin staining pattern. Semi-quantitative PCR of dystrophin revealed a homozygous dystrophin deletion of exons 45-55, which is predicted to remove 593 amino acids without frame shifting. Western blot analysis of skeletal muscle for dystrophin showed a 306 kDa band; thus, we made a diagnosis of female BMD. We confirmed identical deletion in both father and mother, in hemizygous and heterozygous modes, respectively. Neither female Duchenne muscular dystrophy (DMD) nor BMD due to homozygous dystrophin mutation has ever been identified although female DMD has been found in patients with Turner syndrome or unilateral parental disomy for X chromosome. Our results indicate that dystrophinopathy can also be caused in females by homozygosity, albeit rare. PMID:19396825
Fujii, Katsunori; Minami, Narihiro; Hayashi, Yukiko; Nishino, Ichizo; Nonaka, Ikuya; Tanabe, Yuzo; Takanashi, Jun-ichi; Kohno, Yoichi
Summary Background: Facioscapulohumeral muscular dystrophy (FSHD) is the 3rd most common form of muscular dystrophy. Effective treatments for any of the muscular dystrophies have yet to be realized. This report describes such a treatment. Case Report: A 66 year old female was diagnosed with osteoporosis. She had been diagnosed with FSHD muscular dystrophy a number of years previously by both genetic and clinical studies. Following a 2 year course with Forteo for osteoporosis, she was given an injection of Denosumab (Prolia) to maintain her bone density. By 24 hours, she exhibited increased strength and a dramatic reduction of her dystrophic symptoms e.g. she could walk unassisted in high heels. She was able to accomplish other things that had not been possible for a number of years. After approximately 5 weeks she gradually lost the newfound strength with a complete loss by about 6 weeks. A second injection of Denosumab resulted in the same effect, i.e. reversal of symptoms and increased functionality. A number of measurements and videos were taken to establish the beneficial effects of Prolia for future studies. This was repeated with a 3rd and 4th injection in order to establish the unequivocal beneficial effects on muscular dystrophy. Conclusions: Further studies will be required to establish Denosumab as a major “front line” treatment for this disease and possibly other muscular dystrophies.
Lefkowitz, Stanley S.; Lefkowitz, Doris L.; Kethley, Jeremy
Duchenne muscular dystrophy (DMD) is an X-linked, rapidly progressive myopathy affecting the limb muscles, the respiratory\\u000a muscles, the heart, the intestines, and the brain. Since about 90% of DMD patients die from muscular respiratory failure or\\u000a cardiomyopathy, early and adequate therapy is essential. Ventilatory failure from muscle weakness requires mechanical support\\u000a for ventilation and coughing as soon as there is
A late diagnosis of Duchenne muscular dystrophy has implications for both child and family. This repeat audit has shown that the diagnosis continues to be delayed. The failure to recognize that non-motor, and specifically speech and language delay are common features of this disease may detract from the motor difficulties in affected children and contribute to the late diagnosis of
Khalid Mohamed; Richard Appleton; Paola Nicolaides
We used expression profiling to define the pathophysiological cascades involved in the progression of two muscular dystrophies with known primary biochemical defects, dystrophin deficiency (Duchenne muscular dystrophy) and ?-sarcoglycan deficiency (a dystrophin-associated protein). We employed a novel protocol for expression profiling in human tissues using mixed samples of multiple patients and iterative comparisons of duplicate datasets. We found evidence for both incomplete differentiation of patient muscle, and for dedifferentiation of myofibers to alternative lineages with advancing age. One developmentally regulated gene characterized in detail, ?-cardiac actin, showed abnormal persistent expression after birth in 60% of Duchenne dystrophy myofibers. The majority of myofibers (?80%) remained strongly positive for this protein throughout the course of the disease. Other developmentally regulated genes that showed widespread overexpression in these muscular dystrophies included embryonic myosin heavy chain, versican, acetylcholine receptor ?-1, secreted protein, acidic and rich in cysteine/osteonectin, and thrombospondin 4. We hypothesize that the abnormal Ca2+ influx in dystrophin- and ?-sarcoglycan–deficient myofibers leads to altered developmental programming of developing and regenerating myofibers. The finding of upregulation of HLA-DR and factor XIIIa led to the novel identification of activated dendritic cell infiltration in dystrophic muscle; these cells mediate immune responses and likely induce microenvironmental changes in muscle. We also document a general metabolic crisis in dystrophic muscle, with large scale downregulation of nuclear-encoded mitochondrial gene expression. Finally, our expression profiling results show that primary genetic defects can be identified by a reduction in the corresponding RNA.
Chen, Yi-Wen; Zhao, Po; Borup, Rehannah; Hoffman, Eric P.
Serum creatine kinase, myoglobin, and percentage lymphocyte capping was determined in ten patients with Duchenne muscular dystrophy, 12 carriers (nine definite and three probable), 16 other female relatives, and eight normal controls. There was no detectable difference in lymphocyte capping ability between any of these clinical groups. Significant myoglobinaemia was present in all the affected males, but the difference in levels between carriers and controls suggested that this test has no advantage over creatine kinase estimations in carrier detection.
Fitzsimmons, J S; McLachlan, J I; Reeves, W G; Marriott, D W; Woolfson, A M; Mayhew, J
Facioscapulohumeral muscular dystrophy (FSHD) seems to be caused by a complex epigenetic disease mechanism as a result of contraction of the polymorphic macrosatellite repeat D4Z4 on chromosome 4qter. Currently, the exact mechanism causing the FSHD phenotype is still not elucidated. In this review, we discuss the genetic and epigenetic changes observed in patients with FSHD and the possible disease mechanisms that may be associated with FSHD pathogenesis.
de Greef, Jessica C.; Frants, Rune R.; van der Maarel, Silvere M.
A case is reported of a newborn who presented with generalized hypotonia shortly after delivery. Creatine kinase (CK) was highly elevated. Muscle biopsy of the rectus femoris muscle revealed varying sized muscle fibers, displacement by fat and connective tissues, necrosis and regeneration of the muscle fibers. Magnetic resonance imaging (M.R.I.) of the brain showed normal development, compatible with the patient's age. Congenital muscular dystrophy was diagnosed from clinical manifestations, laboratory findings, and the results of muscle biopsy. PMID:8592933
Liang, W H; Lin, J T; Hsiao, L C; Lin, S T
A 60-year-old man diagnosed clinically with Becker's muscular dystrophy 20 years ago by another physician presented with gradually progressive proximal muscle weakness since teenage years. Family history revealed a strong paternal familial inheritance pattern of similar distribution of weakness-face, forearm flexion, knee extension and foot dorsiflexion. Work-ups revealed B12 deficiency and allele 1 deletion in fascioscapulohumeral muscular dystrophy (FSHD) DNA testing. FSHD is the third most common muscular dystrophy. Clinical diagnosis is made from the distinctive pattern of weakness, autosomal-dominant inheritance, and confirmed by genetic testing. This case strongly demonstrates the importance of a thorough and careful clinical evaluation even in a case with a long standing diagnosis. PMID:21795275
Ramos, Vesper Fe Marie Llaneza; Thaisetthawatkul, Pariwat
Duchenne muscular dystrophy (DMD) is familiar to paediatricians as the most common childhood muscular dystrophy and leads to severe disability and early death in the late teenage years if untreated. Improvements in general care, glucocorticoid corticosteroid treatment, non-invasive ventilatory support, and cardiomyopathy and scoliosis management have significantly changed the course of DMD in treated individuals, so that survival into adulthood
A Y Manzur; M Kinali; F Muntoni
Scoliosis is a frequent complication in the non-ambulant patient with Duchenne muscular dystrophy (DMD). Weakness of the paraspinal muscles leads to trunk and body positional changes facilitating the development of a progressive collapsing scoliosis which inevitably interferes with comfortable sitting and may exacerbate deteriorating respiratory function. The recommended international standard of care for management of DMD includes strategies to prolong ambulation which may delay the onset of scoliosis. In the non-ambulant child there should be regular monitoring for scoliosis and, when present, surgical treatment should undertaken at an early stage. Careful multi-disciplinary pre-operative assessment and peri-operative care are essential. PMID:23746543
Hsu, John D; Quinlivan, Ros
Introduction Duchenne muscular dystrophy (DMD) is the most common, severe childhood form of muscular dystrophy. Treatment is limited to glucocorticoids that have the benefit of prolonging ambulation by approximately 2 years and preventing scoliosis. Finding a more satisfactory treatment should focus on maintaining long-term efficacy with a minimal side effect profile. Areas covered Authors discuss different therapeutic strategies that have been used in pre-clinical and clinical settings. Expert opinion Multiple treatment approaches have emerged. Most attractive are molecular-based therapies that can express the missing dystrophin protein (exon skipping or mutation suppression) or a surrogate gene product (utrophin). Other approaches include increasing the strength of muscles (myostatin inhibitors), reducing muscle fibrosis, and decreasing oxidative stress. Additional targets include inhibiting NF-?B to reduce inflammation, or promoting skeletal muscle blood flow and muscle contractility using phosphodiesterase inhibitors or nitric oxide (NO) donors. The potential for each of these treatment strategies to enter clinical trials is a central theme of discussion. The review emphasizes that the goal of treatment should be to find a product at least as good as glucocorticoids with a lower side effect profile or with a significant glucocorticoid sparing effect.
Malik, Vinod; Rodino-Klapac, Louise; Mendell, Jerry R.
Background Mice from the MRL or “superhealing” strain have enhanced repair after acute injury to the skin, cornea, and heart. We now tested an admixture of the MRL genome and found that it altered the course of muscle pathology and cardiac function in a chronic disease model of skeletal and cardiac muscle. Mice lacking ?-sarcoglycan (Sgcg), a dystrophin-associated protein, develop muscular dystrophy and cardiomyopathy similar to their human counterparts with limb girdle muscular dystrophy. With disruption of the dystrophin complex, the muscle plasma membrane becomes leaky and muscles develop increased fibrosis. Methods MRL/MpJ mice were bred with Sgcg mice, and cardiac function was measured. Muscles were assessed for fibrosis and membrane leak using measurements of hydroxyproline and Evans blue dye. Quantitative trait locus mapping was conducted using single nucleotide polymorphisms distinct between the two parental strains. Results Introduction of the MRL genome reduced fibrosis but did not alter membrane leak in skeletal muscle of the Sgcg model. The MRL genome was also associated with improved cardiac function with reversal of depressed fractional shortening and the left ventricular ejection fraction. We conducted a genome-wide analysis of genetic modifiers and found that a region on chromosome 2 was associated with cardiac, diaphragm muscle and abdominal muscle fibrosis. Conclusions These data are consistent with a model where the MRL genome acts in a dominant manner to suppress fibrosis in this chronic disease setting of heart and muscle disease.
Background In Facioscapulohumeral muscular dystrophy (FSHD), the upper girdle is early involved and often difficult to assess only relying on physical examination. Our aim was to evaluate the pattern and degree of involvement of upper girdle muscles in FSHD compared with other muscle diseases with scapular girdle impairment. Methods We propose an MRI protocol evaluating neck and upper girdle muscles. One hundred-eight consecutive symptomatic FSHD patients and 45 patients affected by muscular dystrophies and myopathies with prominent upper girdle involvement underwent this protocol. Acquired scans were retrospectively analyzed. Results The trapezius (100% of the patients) and serratus anterior (85% of the patients) were the most and earliest affected muscles in FSHD, followed by the latissimus dorsi and pectoralis major, whilst spinati and subscapularis (involved in less than 4% of the patients) were consistently spared even in late disease stages. Asymmetry and hyperintensities on short-tau inversion recovery (STIR) sequences were common features, and STIR hyperintensities could also be found in muscles not showing signs of fatty replacement. The overall involvement appears to be disease-specific in FSHD as it significantly differed from that encountered in the other myopathies. Conclusions The detailed knowledge of single muscle involvement provides useful information for correctly evaluating patients' motor function and to set a baseline for natural history studies. Upper girdle imaging can also be used as an additional tool helpful in supporting the diagnosis of FSHD in unclear situations, and may contribute with hints on the currently largely unknown molecular pathogenesis of this disease.
Tasca, Giorgio; Monforte, Mauro; Iannaccone, Elisabetta; Laschena, Francesco; Ottaviani, Pierfrancesco; Leoncini, Emanuele; Boccia, Stefania; Galluzzi, Giuliana; Pelliccioni, Marco; Masciullo, Marcella; Frusciante, Roberto; Mercuri, Eugenio; Ricci, Enzo
Facioscapulohumeral muscular dystrophy (FSHD) is the third most common muscular dystrophy after the dystrophinopathies and myotonic dystrophy and is associated with a typical pattern of muscle weakness. Most patients with FSHD carry a large deletion in the polymorphic D4Z4 macrosatellite repeat array at 4q35 and present with 1-10 repeats whereas non-affected individuals possess 11-150 repeats. An almost identical repeat array is present at 10q26 and the high sequence identity between these two arrays can cause difficulties in molecular diagnosis. Each 3.3-kb D4Z4 unit contains a DUX4 (double homeobox 4) gene that, among others, is activated upon contraction of the 4q35 repeat array due to the induction of chromatin remodelling of the 4qter region. A number of 4q subtelomeric sequence variants are now recognised, although FSHD only occurs in association with three 'permissive' haplotypes, each of which is associated with a polyadenylation signal located immediately distal of the last D4Z4 unit. The resulting poly-A tail appears to stabilise DUX4 mRNAs transcribed from this most distal D4Z4 unit in FSHD muscle cells. Synthesis of both the DUX4 transcripts and protein in FSHD muscle cells induces significant cell toxicity. DUX4 is a transcription factor that may target several genes which results in a deregulation cascade which inhibits myogenesis, sensitises cells to oxidative stress and induces muscle atrophy, thus recapitulating many of the key molecular features of FSHD. PMID:21984394
Richards, Mark; Coppée, Frédérique; Thomas, Nick; Belayew, Alexandra; Upadhyaya, Meena
Congenital muscular dystrophies (CMDs) are clinically and genetically heterogeneous neuromuscular disorders with onset at birth or in infancy in which the muscle biopsy is compatible with a dystrophic myopathy. In the past 10 years, knowledge of neuromuscular disorders has dramatically increased, particularly with the exponential boost of disclosing the genetic background of CMDs. This review will highlight the clinical description of the most important forms of CMD, paying particular attention to the main keys for diagnostic approach. The diagnosis of CMDs requires the concurrence of expertise in multiple specialties (neurology, morphology, genetics, neuroradiology) available in a few centers worldwide that have achieved sufficient experience with the different CMD subtypes. Currently, molecular diagnosis is of paramount importance not only for phenotype-genotype correlations, genetic and prenatal counseling, and prognosis and aspects of management, but also concerning the imminent availability of clinical trials and treatments.
Bertini, Enrico; D'Amico, Adele; Gualandi, Francesca; Petrini, Stefania
Four cases of congenital, hypotonic-sclerotic muscular dystrophy are presented. The patients showed clinically prominent features described by Ullrich, i.e. congenital muscle weakness, hypotonia, and hyperextensibility of distal joints, contractures of proximal joints, high-arched palate, hyperhidrosis, posterior protrusion of calcaneus, and no progression. Muscle biopsies revealed dystrophic changes. Ullrich suggested that this condition was a new entity, but the disease has received little attention. In the present cases superior intelligence and tendency to recurrent upper respiratory tract infections were stressed as characteristics of this disorder. Insufficient cellular immunity was suspected and this may contribute to the recurrent upper respiratory tract infections and pneumonia often observed. This disease is considered a distinct entity of multisystemic involvement inherited as an autosomal recessive trait. Images
Furukawa, T; Toyokura, Y
Muscular dystrophies (MD) constitute a group of inherited disorders characterized by progressive weakness of skeletal and sometimes cardiac muscle. MD are rare disorders affecting approximately 26,000 to 40,000 people in Germany based on a pre valence of 1:2000 to 1:3000 (estimate of the Association Française contre les Myopathies, AFM) and a population of 80 million people residing in Germany. More than 30 forms of MD are recognized today caused by different genetic defects. Based on the symptoms of an individual patient the underlying genetic defect cannot be determined, since all MD have the following in common: Muscle fibers are destroyed and become replaced by fatty and fibrous tissue. Various forms of MD are caused by defects of proteins residing in the sarcolemma, the cell membrane of muscle fibers. Other forms are caused by defects of proteins that are associated to the nucleus, to the sarcomer or the cytoplasm. Moreover, there are numerous forms where the exact molecular defect is unknown to date. Even though the underlying defect is known for many MD, the pathogenic process that leads to the decay of musculature is poorly understood. At present, MD cannot be cured. MD are treated by physiotherapy, surgery and medication that may delay progression. Symptomatic therapy such as cardiac pace makers may be life-saving and improve quality of life in many patients. For optimizing research into the MD, a network, the muscular dystrophy network or MD-NET, was initiated and has been supported by the German ministry of education and research (BMBF) since 2003. PMID:18026885
Lochmüller, H; Straub, V
... a DMD gene mutation also have an increased risk of developing heart abnormalities including cardiomyopathy. Where can I find information about diagnosis or management of Duchenne and Becker muscular dystrophy? These resources ...
Leonard RJ, Kendall KA, Johnson R, McKenzie S. Swallowing in myotonic muscular dystrophy: a videofluoroscopic study. Arch Phys Med Rehabil 2001;82:979-85. Objectives: (1) To determine how swallow function in patients with myotonic muscular dystrophy (MD) differs from that of healthy controls, (2) to identify the contributors to and predictors of improvement, and (3) to evaluate strategies that facilitate swallowing. Design:
Rebecca J. Leonard; Katherine A. Kendall; Ralph Johnson; Susan McKenzie
This case report describes a young boy with concomitant genetically-confirmed Duchenne muscular dystrophy and facioscapulohumeral muscular dystrophy with a novel dystrophin mutation in exon 6 and a D4Z4 fragment of 31 kb. This child presented with a more severe phenotype than expected for either individual disease process and underscores the role for thorough diagnostic investigation in identifying atypical clinical presentations. PMID:18586493
Korngut, Lawrence; Siu, Victoria M; Venance, Shannon L; Levin, Simon; Ray, Peter; Lemmers, Richard J L F; Keith, Julia; Campbell, Craig
We report a 31-year-old man with facioscapulohumeral muscular dystrophy who had congenital anomalies and mental retardation. Southern blot analysis, using the probe p13E-11, displayed an abnormal EcoRI DNA fragment that reflect DNA rearrangements in facioscapulohumeral muscular dystrophy. In addition, high-resolution cytogenetic study revealed an interstitial deletion of the short arm chromosome 9: 46,XY,del(9)(p.22.1p24.1). PMID:8614537
Ueyama, H; Kumamoto, T; Mita, S; Kimura, E; Nakagawa, M; Uchino, M; Ando, M
Common metabolic and endocrine alterations exist across a wide range of muscular dystrophies. Skeletal muscle plays an important role in glucose metabolism and is a major participant in different signaling pathways. Therefore, its damage may lead to different metabolic disruptions. Two of the most important metabolic alterations in muscular dystrophies may be insulin resistance and obesity. However, only insulin resistance has been demonstrated in myotonic dystrophy. In addition, endocrine disturbances such as hypogonadism, low levels of testosterone, and growth hormone have been reported. This eventually will result in consequences such as growth failure and delayed puberty in the case of childhood dystrophies. Other consequences may be reduced male fertility, reduced spermatogenesis, and oligospermia, both in childhood as well as in adult muscular dystrophies. These facts all suggest that there is a need for better comprehension of metabolic and endocrine implications for muscular dystrophies with the purpose of developing improved clinical treatments and/or improvements in the quality of life of patients with dystrophy. Therefore, the aim of this paper is to describe the current knowledge about of metabolic and endocrine alterations in diverse types of dystrophinopathies, which will be divided into two groups: childhood and adult dystrophies which have different age of onset.
Cruz Guzman, Oriana del Rocio; Chavez Garcia, Ana Laura; Rodriguez-Cruz, Maricela
Background Left ventricular noncompaction (LVNC) describes deep trabeculations in the left ventricular (LV) endocardium and a thinned epicardium. LVNC is seen both as a primary cardiomyopathy and as a secondary finding in other syndromes affecting the myocardium such as neuromuscular disorders. The objective of this study is to define the prevalence of LVNC in the Duchenne Muscular Dystrophy (DMD) population and characterize its relationship to global LV function. Methods Cardiac magnetic resonance (CMR) was used to assess ventricular morphology and function in 151 subjects: DMD with ejection fraction (EF)?>?55% (n?=?66), DMD with EF?55% (n?=?30), primary LVNC (n?=?15) and normal controls (n?=?40). The non-compacted to compacted (NC/C) ratio was measured in each of the 16 standard myocardial segments. LVNC was defined as a diastolic NC/C ratio?>?2.3 for any segment. Results LVNC criteria were met by 27/96 DMD patients (prevalence of 28%): 11 had an EF?>?55% (prevalence of 16.7%), and 16 had an EF?55% (prevalence of 53.3%). The median maximum NC/C ratio was 1.8 for DMD with EF?>?55%, 2.46 for DMD with EF?55%, 1.54 for the normal subjects, and 3.69 for primary LVNC patients. Longitudinal data for 78 of the DMD boys demonstrated a mean rate of change in NC/C ratio per year of +0.36. Conclusion The high prevalence of LVNC in DMD is associated with decreased LV systolic function that develops over time and may represent muscular degeneration versus compensatory remodeling.
The objective of this study was to determine the prevalence, circumstances, and outcome of fractures in males with Duchenne muscular dystrophy (DMD) attending neuromuscular clinics. Three hundred and seventy-eight males (median age 12 years, range 1 to 25 years) attending four neuromuscular centres were studied by case-note review supplemented by GP letter or by interview at the time of clinic attendance. Seventy-nine (20.9%) of these patients had experienced fractures. Forty-one percent of fractures were in patients aged 8 to 11 years and 48% in independently ambulant patients. Falling was the most common mechanism of fracture. Upper-limb fractures were most common in males using knee-ankle-foot orthoses (65%) while lower-limb fractures predominated in independently mobile and wheelchair dependent males (54% and 68% respectively). Twenty percent of ambulant males and 27% of those using orthoses lost mobility permanently as a result of the fracture. In a substantial proportion of males, the occurrence of a fracture had a significant impact on subsequent mobility. PMID:12418795
McDonald, Denise G M; Kinali, Maria; Gallagher, Andrew C; Mercuri, Eugenio; Muntoni, Francesco; Roper, Helen; Jardine, Philip; Jones, David Hilton; Pike, M G
?-Filamin, also called ABP-L, is a filamin isoform that is specifically expressed in striated muscles, where it is predominantly localized in myofibrillar Z-discs. A minor fraction of the protein shows subsarcolemmal localization. Although ?-filamin has the same overall structure as the two other known isoforms, it is the only isoform that carries a unique insertion in its immunoglobulin (Ig)-like domain 20. Sequencing of the genomic region encoding this part of the molecule shows that this insert is encoded by an extra exon. Transient transfections of the insert-bearing domain in skeletal muscle cells and cardiomyocytes show that this single domain is sufficient for targeting to developing and mature Z-discs. The yeast two-hybrid method was used to identify possible binding partners for the insert-bearing Ig-like domain 20 of ?-filamin. The two Ig-like domains of the recently described ?-actinin–binding Z-disc protein myotilin were found to interact directly with this filamin domain, indicating that the amino-terminal end of ?-filamin may be indirectly anchored to ?-actinin in the Z-disc via myotilin. Since defects in the myotilin gene were recently reported to cause a form of autosomal dominant limb-girdle muscular dystrophy, our findings provide a further contribution to the molecular understanding of this disease.
van der Ven, Peter F.M.; Wiesner, Sebastian; Salmikangas, Paula; Auerbach, Daniel; Himmel, Mirko; Kempa, Stefan; Hayess, Katrin; Pacholsky, Dirk; Taivainen, Anu; Schroder, Rolf; Carpen, Olli; Furst, Dieter O.
Duchenne muscular dystrophy (DMD) is a fatal X-linked degenerative muscle disease caused by the absence of the microtubule-associated protein dystrophin, which results in a disorganized and denser microtubule cytoskeleton. In addition, mechanotransduction-dependent activation of calcium (Ca2+) and reactive oxygen species (ROS) signaling underpins muscle degeneration in DMD. We show that in muscle from adult mdx mice, a model of DMD, a brief physiologic stretch elicited microtubule-dependent activation of NADPH (reduced-form nicotinamide adenine dinucleotide phosphate) oxidase–dependent production of ROS, termed X-ROS. Further, X-ROS amplified Ca2+ influx through stretch-activated channels in mdx muscle. Consistent with the importance of the microtubules to the dysfunction in mdx muscle, muscle cells with dense microtubule structure, such as those from adult mdx mice or from young wild-type mice treated with Taxol, showed increased X-ROS production and Ca2+ influx, whereas cells with a less dense microtubule network, such as young mdx or adult mdx muscle treated with colchicine or nocodazole, showed little ROS production or Ca2+ influx. In vivo treatments that disrupted the microtubule network or inhibited NADPH oxidase 2 reduced contraction-induced injury in adult mdx mice. Furthermore, transcriptome analysis identified increased expression of X-ROS–related genes in human DMD skeletal muscle. Together, these data show that microtubules are the proximate element responsible for the dysfunction in Ca2+ and ROS signaling in DMD and could be effective therapeutic targets for intervention.
Khairallah, Ramzi J.; Shi, Guoli; Sbrana, Francesca; Prosser, Benjamin L.; Borroto, Carlos; Mazaitis, Mark J.; Hoffman, Eric P.; Mahurkar, Anup; Sachs, Fredrick; Sun, Yezhou; Chen, Yi-Wen; Raiteri, Roberto; Lederer, W. Jonathan; Dorsey, Susan G.; Ward, Christopher W.
A 44-year-old male patient with known Becker muscular dystrophy and concomitant non-ischemic dilated cardiomyopathy presented to our department because of worsening heart failure and presyncope. Upon admission, the patient was in New York Heart Association functional class III despite optimal pharmacological treatment; his ECG showed sinus rhythm with left bundle branch block and a wide QRS complex. Non-sustained ventricular tachycardia was recorded during 24-hour Holter monitoring. A complete three-dimensional echocardiographic study was performed and documented the dilatation and concomitant hypertrabeculation of the left ventricle (LV), with severely depressed systolic LV performance (ejection fraction 20%), as well as mechanical dyssynchrony--mainly in terms of intraventricular delay. A biventricular cardioverter-defibrillator (CRT-D) was implanted in this patient, with the LV lead in a lateral vein and the right ventricular defibrillating lead in the apical part of the interventricular septum. Echocardiography-guided device programming was performed in order to achieve the optimal atrio-, inter-, and intraventricular resynchronization. The patient's clinical condition was substantially improved within one month after the implantation. PMID:23685662
Andrikopoulos, George; Kourouklis, Spiros; Trika, Chrysanthi; Tzeis, Stylianos; Rassias, Ioannis; Papademetriou, Christos; Katsivas, Apostolos; Theodorakis, George
The purpose of this long-term, open parallel-group, double-consent study of alternate-day, low-dose prednisone in 2-4-year-old patients with Duchenne muscular dystrophy (DMD) was to determine whether prednisone produces a beneficial effect when given earlier than usual. Muscle function was evaluated by timed tests, and muscle strength with a hand-held myometer. After 55 months of treatment, the five patients (mean age 8.3 years) in the prednisone group were still able to get up from the floor, whereas two of the three in the control group had lost this ability. Side effects included a decline in growth rate in the prednisone-treated patients and excessive weight gain in one control and three treated patients. Because steroids are effective in prolonging function, but not in recovering lost function, we propose that treatment be started with low-dose prednisone in DMD patients as soon as the diagnosis is definite. PMID:12548530
Merlini, Luciano; Cicognani, Alessandro; Malaspina, Elisabetta; Gennari, Monia; Gnudi, Saverio; Talim, Beril; Franzoni, Emilio
Background Ptosis and dysphagia are important features in oculopharyngeal muscular dystrophy (OPMD). Objective Retroflexion of the head is a well known compensatory mechanism for ptosis, but generally retroflexion has a negative effect on swallowing. We hypothesised that severity of ptosis is related to degree of retroflexion and that this compensation is responsible for deteriorating dysphagia. Methods Nine OPMD patients were examined in the conditions “head position adapted to ptosis” and “head position slightly flexed”. Ptosis was quantified by photogrammetry and retroflexion of the head by digital photographs. The severity of dysphagia was measured using visual analogue scales (VAS) and by calculating swallowing volumes and oropharyngeal swallow efficiency (OPSE) based on videofluoroscopy. Results Statistical analyses show a significant relationship between ptosis and degree of retroflexion. The degree of retroflexion of the head correlated significantly with VAS scores and with the maximum swallowing volume. The slightly flexed head position significantly improved VAS scores as well as swallowing volumes and OPSE. Conclusion In OPMD patients, ptosis significantly correlates with retroflexion of the head, which has a negative effect on swallowing. Subjective and objective reduction of swallowing problems was found when patients were instructed to eat and drink with a slightly flexed head position.
de Swart, B J M; van der Sluijs, B M; Vos, A M C; Kalf, J G; Knuijt, S; Cruysberg, J R M; van Engelen, B G M
DUX4, a homeobox-containing gene present in a tandem array, is implicated in facioscapulohumeral muscular dystrophy (FSHD), a dominant autosomal disease. New findings about DUX4 have raised as many fundamental questions about the molecular pathology of this unique disease as they have answered. This review discusses recent studies addressing the question of whether there is extensive FSHD-related transcription dysregulation in adult-derived myoblasts and myotubes, the precursors for muscle repair. Two models for the role of DUX4 in FSHD are presented. One involves transient pathogenic expression of DUX4 in many cells in the muscle lineage before the myoblast stage resulting in a persistent, disease-related transcription profile ('Majority Rules'), which might be enhanced by subsequent oscillatory expression of DUX4. The other model emphasizes the toxic effects of inappropriate expression of DUX4 in only an extremely small percentage of FSHD myoblasts or myotube nuclei ('Minority Rules'). The currently favored Minority Rules model is not supported by recent studies of transcription dysregulation in FSHD myoblasts and myotubes. It also presents other difficulties, for example, explaining the expression of full-length DUX4 transcripts in FSHD fibroblasts. The Majority Rules model is the simpler explanation of findings about FSHD-associated gene expression and the DUX4-encoded homeodomain-type protein. PMID:22718021
Ehrlich, Melanie; Lacey, Michelle
The presence of nonprogressive cognitive impairment is recognized as a common feature in a substantial proportion of patients with Duchenne muscular dystrophy. To investigate the possible role of mutations along the dystrophin gene affecting different brain dystrophin isoforms and specific cognitive profiles, 42 school-age children affected with Duchenne muscular dystrophy, subdivided according to sites of mutations along the dystrophin gene, underwent a battery of tests tapping a wide range of intellectual, linguistic, and neuropsychologic functions. Full-scale intelligence quotient was approximately 1 S.D. below the population average in the whole group of dystrophic children. Patients with Duchenne muscular dystrophy and mutations located in the distal portion of the dystrophin gene (involving the 140-kDa brain protein isoform, called Dp140) were generally more severely affected and expressed different patterns of strengths and impairments, compared with patients with Duchenne muscular dystrophy and mutations located in the proximal portion of the dystrophin gene (not involving Dp140). Patients with Duchenne muscular dystrophy and distal mutations demonstrated specific impairments in visuospatial functions and visual memory (which seemed intact in proximally mutated patients) and greater impairment in syntactic processing.
D'Angelo, Maria Grazia; Lorusso, Maria Luisa; Civati, Federica; Comi, Giacomo Pietro; Magri, Francesca; Del Bo, Roberto; Guglieri, Michela; Molteni, Massimo; Turconi, Anna Carla; Bresolin, Nereo
Duchenne muscular dystrophy is an X-linked, recessively inherited disorder characterized by progressive weakness attributable to the absence of dystrophin expression in muscle. In multiple studies, the chronic administration of corticosteroids slowed the loss of ambulation that develops in mid to late childhood. Corticosteroids, however, frequently produce unacceptable side effects, including Cushingoid appearance and weight gain. Deflazacort, an oxazoline analogue of prednisolone, produces equivalent benefits on muscle with fewer reported Cushingoid side effects. We present a 9-year-old boy with Duchenne muscular dystrophy who developed morbid obesity and subsequent idiopathic intracranial hypertension after 2 years of receiving deflazacort. Although deflazacort is typically thought to produce less obesity than prednisone, severe Cushingoid side effects may occur in some individuals. To our knowledge, this description is the first of idiopathic intracranial hypertension complicating chronic corticosteroid treatment of Duchenne muscular dystrophy. PMID:22115006
Weig, Spencer G; Zinn, Matthias M; Howard, James F
Dilated cardiomyopathy is a serious and almost inevitable complication of Duchenne Muscular Dystrophy, a devastating and fatal disease of skeletal muscle resulting from the lack of functional dystrophin, a protein linking the cytoskeleton to the extracellular matrix. Ultimately, it leads to congestive heart failure and arrhythmias resulting from both cardiac muscle fibrosis and impaired function of the remaining cardiomyocytes. Here we summarize findings obtained in several laboratories, focussing on cellular mechanisms that result in degradation of cardiac functions in dystrophy.
Shirokova, Natalia; Niggli, Ernst
The main goal in the treatment of Duchenne muscular dystrophy (DMD) is to maintain ambulation for as long as possible and to anticipate and manage the associated complications, such as joint contractures, scoliosis, cardiomyopathy, respiratory insufficiency, and weight gain. Cognitive and behavioral symptoms occur in about one third of patients, and it is important to recognize and manage them promptly, developing an individualized plan at school and at home to maximize the patient's cognitive abilities. In the late phase of the disease, palliative care is of paramount importance. Corticosteroid therapy (prednisone and deflazacort) is the only effective pharmacologic treatment for DMD. Daily prednisone treatment increases muscle strength and function, improves pulmonary function, and significantly slows the progression of weakness. Deflazacort has a similar effect on muscle strength, but it is not available in the United States. Treatment with corticosteroid should be offered to all patients with DMD, but the beneficial effects and potential adverse effects should be fully discussed before treatment begins. The optimal dose of prednisone is 0.75 mg/kg per day, up to a maximum of 40 mg/d. If adverse effects occur, a decrease in dosage is appropriate. Monitoring of muscle function and adverse effects by a neurologist or neuromuscular specialist is strongly recommended. Physical and occupational therapists should be involved early in the treatment of patients with DMD to develop a program that includes heel cord stretching and exercise. In the later phases, these therapists can recommend adaptive equipment and maximize independence. Orthopedic consultation is important in monitoring and managing scoliosis and joint contractures in the nonambulatory phase of the disease. Pulmonary evaluation for ventilatory care is important; pulmonary consultation is essential when vital capacity declines. The use of assistive cough devices, nasal bilevel positive airway pressure, and tracheostomy must be discussed with patients and their families. For all patients with DMD, particularly those receiving prednisone, consultation with a dietitian is very helpful to control weight and maintain a healthy diet. PMID:18334131
Ciafaloni, Emma; Moxley, Richard T
Mutations in the ?-sarcoglycan gene cause limb-girdle muscular dystrophy 2F (LGMD2F), an autosomal recessive disease that causes progressive weakness and wasting of the proximal limb muscles and often has cardiac involvement. Here we review the clinical implications of LGMD2F and discuss the current understanding of the putative mechanisms underlying its pathogenesis. Preclinical research has benefited enormously from various animal models of ?-sarcoglycan deficiency, which have helped researchers to explore therapeutic approaches for both muscular dystrophy and cardiomyopathy.
Muscle diseases can take many forms, from the progressive muscle degeneration of dystrophies to the childhood cancer rhabdomyosarcoma. In 'Bench to Bedside', Joel R. Chamberlain and Jeffrey S. Chamberlain discuss studies using antisense oligonucleotides to treat Duchenne muscular dystrophy and myotonic dystrophy. In 'Bedside to Bench', Simone Hettmer and Amy J. Wagers examine the implications of clinical studies describing a type of rhabdomyosarcoma that resembles acute leukemia. The findings dovetail with other studies suggesting that some of these cancers might originate outside of muscle tissue and highlight the need for a better understanding of the cells that give rise to this condition. PMID:20134472
Chamberlain, Joel R; Chamberlain, Jeffrey S
Duchenne muscular dystrophy (DMD) is a lethal muscle disease for which an effective treatment is urgently needed. The use of stem cells to produce normal muscle cells to replace the missing dystrophin protein has attracted much attention. Claims of success using stem cell treatment in animal models of human muscle diseases require careful evaluation and are not necessarily easily extrapolated
Miranda D. Grounds; Kay E. Davies
BACKGROUND: Cardiac dysfunction in boys with Duchenne muscular dystrophy (DMD) is a leading cause of death. Cardiac resynchronization therapy (CRT) has been shown to dramatically decrease mortality in eligible adult population with congestive heart failure. We hypothesized that mechanical dyssynchrony is present in DMD patients and that cardiovascular magnetic resonance (CMR) may predict CRT efficacy. METHODS: DMD patients (n =
Kan N Hor; Janaka P Wansapura; Hussein R Al-Khalidi; William M Gottliebson; Michael D Taylor; Richard J Czosek; Sherif F Nagueh; Nandakishore Akula; Eugene S Chung; Woodrow D Benson; Wojciech Mazur
BACKGROUND: Although previous studies have helped define the natural history of Duchenne Muscular Dystrophy (DMD)-associated cardiomyopathy, the myocardial pathobiology associated with functional impairment in DMD is not yet known. The objective of this study was to assess the distribution of transverse relaxation time (T2) in the left ventricle (LV) of DMD patients, and to determine the association of myocardial T2
Janaka P Wansapura; Kan N Hor; Wojciech Mazur; Robert Fleck; Sean Hagenbuch; D Woodrow Benson; William M Gottliebson
Sirs: The muscles involved in the Duchenne type of muscular dystrophy (DMD) are predominantly proximal but, as the disease progresses, become generalized. The patient's death usually occurs before the 20th year, most often due to respiratory complications. The ability to defecate remains normal until the terminal stage . Computed tomography (CT) of skeletal muscles has revealed morphological changes in the
T. Ohtake; R. Takahashi; T. Nagashima; K. Hirose; H. Tanabe
Muscular dystrophies such as Duchenne muscular dystrophy (DMD) are usually approached as dysfunctions of the affected skeletal myofibres and their force transmission. Comparatively little attention has been given to the increase in connective tissue (fibrosis) which accompanies these muscular changes. Interestingly, an increase in endomysial tissue is apparent long before any muscular degeneration can be observed. Fibrosis is the result of a reactive or reparative process involving mechanical, humoral and cellular factors. Originating from vulnerable myofibres, muscle cell necrosis and inflammatory processes are present in DMD. Muscular recovery is limited due to the limited number and capacity of satellite cells. Hence, a proactive and multimodal approach is necessary in order to activate protective mechanisms and to hinder catabolic and tissue degrading pathways. Several avenues are discussed in terms of potential antifibrotic therapy approaches. These include pharmaceutical, nutritional, exercise-based and other mechanostimulatory modalities (such as massage or yoga-like stretching) with the intention of exerting an anti-inflammatory and antifibrotic effect on the affected muscular tissues. A preventive intervention at an early age is crucial, based on the early and seemingly non-reversible nature of the fibrotic tissue changes. Since consistent assessment is essential, different measurement technologies are discussed. PMID:23620650
Klingler, Werner; Jurkat-Rott, Karin; Lehmann-Horn, Frank; Schleip, Robert
Dystrophin deficiency results in lethal Duchenne muscular dystrophy (DMD). Substituting missing dystrophin with abbreviated microdystrophin has dramatically alleviated disease in mouse DMD models. Unfortunately, translation of microdystrophin therapy has been unsuccessful in dystrophic dogs, the only large mammalian model. Approximately 70% of the dystrophin-coding sequence is removed in microdystrophin. Intriguingly, loss of ?50% dystrophin frequently results in severe disease in patients. To test whether the small gene size constitutes a fundamental design error for large mammalian muscle, we performed a comprehensive study using 22 dogs (8 normal and 14 dystrophic). We delivered the ?R2-15/?R18-19/?R20-23/?C microdystrophin gene to eight extensor carpi ulnaris (ECU) muscles in six dystrophic dogs using Y713F tyrosine mutant adeno-associated virus (AAV)-9 (2.6 × 1013 viral genome (vg) particles/muscle). Robust expression was observed 2 months later despite T-cell infiltration. Major components of the dystrophin-associated glycoprotein complex (DGC) were restored by microdystrophin. Treated muscle showed less inflammation, fibrosis, and calcification. Importantly, therapy significantly preserved muscle force under the stress of repeated cycles of eccentric contraction. Our results have established the proof-of-concept for microdystrophin therapy in dystrophic muscles of large mammals and set the stage for clinical trial in human patients.
Shin, Jin-Hong; Pan, Xiufang; Hakim, Chady H; Yang, Hsiao T; Yue, Yongping; Zhang, Keqing; Terjung, Ronald L; Duan, Dongsheng
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Muscle fibers attach to laminin in the basal lamina using two distinct mechanisms: the dystrophin gly- coprotein complex and the a 7 b 1 integrin. Defects in these linkage systems result in Duchenne muscular dystro- phy (DMD), a 2 laminin congenital muscular dystrophy, sarcoglycan-related muscular dystrophy, and a 7 integrin congenital muscular dystrophy. Therefore, the molecular continuity between the extracellular
Dean J. Burkin; Gregory Q. Wallace; Kimberly J. Nicol; David J. Kaufman; Stephen J. Kaufman
Antisense oligonucleotides are short nucleic acids designed to bind to specific messenger RNAs in order to modulate splicing patterns or inhibit protein translation. As such, they represent promising therapeutic tools for many disorders and have been actively developed for more than 20 years as a form of molecular medicine. Although significant progress has been made in developing these agents as drugs, they are yet not recognized as effective therapeutics and several hurdles remain to be overcome. Within the last few years, however, the prospect of successful oligonucleotides-based therapies has moved a step closer, in particular for Duchenne muscular dystrophy. Clinical trials have recently been conducted for this myopathy, where exon skipping is being used to achieve therapeutic outcomes. In this review, the recent developments and clinical trials using antisense oligonucleotides for Duchenne muscular dystrophy are discussed, with emphasis on the challenges ahead for this type of therapy, especially with regards to delivery and regulatory issues.
Myoglobinuria is a recognised complication of Duchenne muscular dystrophy (DMD), but has only once been reported in ambulant boys on corticosteroid therapy [Dubowitz V, Kinali M, Main M, Mercuri E, Muntoni F. Remission of clinical signs in early Duchenne muscular dystrophy on intermittent low-dosage prednisolone therapy. Eur J Paediatr Neurol 2002;6(3):153-9.]. We present three prednisolone-treated boys with myoglobinuria and in two cases this was recurrent. All three showed improved motor performance in response to the introduction of corticosteroids. The greater activity of steroid-treated individuals may place their dystrophin-deficient muscles under greater mechanical stress, predisposing to further muscle fibre damage and consequent myoglobinuria. Families and physicians need to have an increased awareness of this possibility and of the appropriate management of myoglobinuria. PMID:17719224
Garrood, P; Eagle, M; Jardine, P E; Bushby, K; Straub, V
Duchenne muscular dystrophy (DMD) is a devastating muscle disorder that affects 1 in 3500 boys. Despite years of research and considerable progress in understanding the molecular mechanism of the disease and advancement of therapeutic approaches, there is no cure for DMD. The current treatment options are limited to physiotherapy and corticosteroids, and although they provide a substantial improvement in affected children, they only slow the course of the disorder. On a more optimistic note, the most recent approaches either significantly alleviate or eliminate muscular dystrophy in murine and canine models of DMD and importantly, many of them are being tested in early phase human clinical trials. This review summarizes advancements that have been made in viral and non-viral gene therapy as well as stem cell therapy for DMD with a focus on the replacement and repair of the affected dystrophin gene.
Konieczny, Patryk; Swiderski, Kristy; Chamberlain, Jeffrey S.
Duchenne muscular dystrophy (DMD) is the commonest of the muscular dystrophies. The DMD gene (DMD) is the biggest human gene and the most common molecular defect in the DMD gene, accounting for approximately 65 % of cases of DMD, is the deletion of one or more exons. The most basic method still in regular use involves multiplex PCR of the exons, known to be most commonly deleted. The multiplex is relatively simple. Quantitative analysis of all exons of the gene and multiplex ligation-dependent probe amplification have brought about an improvement in mutation detection rate, as they will detect all exon scale deletions as well as duplications, widely used to detect exonic and intronic mutations. As a sensitive and discriminative tool, MLPA can be used for prenatal testing. A more recent development in quantitative analysis is the use of oligonucleotide-based array comparative genomic hybridization. PMID:23381834
Itto, Afaf Ben; Hamzi, Khalil; Bellayou, Hanane; Itri, Mohammed; Slassi, Ilham; Nadifi, Sellama
Objective: Myostatin is an endogenous negative regulator of muscle growth and a novel target for muscle diseases. We con- ducted a safety trial of a neutralizing antibody to myostatin, MYO-029, in adult muscular dystrophies (Becker muscular dys- trophy, facioscapulohumeral dystrophy, and limb-girdle muscular dystrophy). Methods: This double-blind, placebo-controlled, multinational, randomized study included 116 subjects divided into sequential dose-escalation cohorts, each
Kathryn R. Wagner; James L. Fleckenstein; Anthony A. Amato; Richard J. Barohn; Katharine Bushby; Diana M. Escolar; Kevin M. Flanigan; Alan Pestronk; Rabi Tawil; Gil I. Wolfe; Michelle Eagle; Julaine M. Florence; Wendy M. King; Shree Pandya; Volker Straub; Paul Juneau; Kathleen Meyers; Cristina Csimma; Tracey Araujo; Robert Allen; Stephanie A. Parsons; John M. Wozney; Edward R. LaVallie; Jerry R. Mendell
The goal of this study was to quantify the two-dimensional kinematics of pathologic gait during over-ground walking at a self-selected speed at the stifle (knee) and hock (ankle) joints in six Golden Retriever Muscular Dystrophy (GRMD) dogs and six carrier littermates (controls). We found that GRMD dogs walked significantly slower than controls (p<0.01). At the stifle joint, both groups displayed
Anthony P. Marsh; Joel D. Eggebeen; Joe N. Kornegay; Chad D. Markert; Martin K. Childers
Molecular deletion screening with cDNA probes from the dystrophin gene was undertaken in patients with Becker muscular dystrophy from 58 separate families. Deletions were found in 41 (71%) of these families. Thirty-four (83%) of the deletions started in the same intron near the centre of the gene, and although there was no precise correlation between clinical severity and deletion pattern, the commonest deletion pattern, which was present in 49% of all deletion families, is associated with a mild phenotype.
Norman, A M; Thomas, N S; Kingston, H M; Harper, P S
c , Goyang, Korea Background: Facioscapulohumeral muscular dystrophy (FSHD) is associated wi th contractions of the polymorphic D4Z4-repeat array in 4q35 and has the distinctive clinical presentation of an initial involvement of the facial, shoulder-girdle, and upper-arm muscles. The aim of the present study was to determine clinical characteristics in Korean patients with FSHD and potential relationships between c ontracted
Ji-Man Hong; Seung-Min Kim; Il-Nam Sunwoo; Kwon-Duk Seo; Dong-Suk Shim; Bum-Chun Suh; Dae-Seong Kim; Jeong-Hee Cho; Young-Chul Choi
Background Progressive cardiomyopathy is a common cause of death in Duchenne muscular dystrophy (DMD), presumably secondary to fibrosis\\u000a of the myocardium. The posterobasal and left lateral free wall of the left ventricle (LV) are initial sites of myocardial\\u000a fibrosis pathologically. The purposes of this study were to assess whether cardiac magnetic resonance imaging (CMRI), utilizing\\u000a late gadolinium enhancement (LGE), could
Michael D. Puchalski; Richard V. Williams; Bojana Askovich; C. Todd Sower; Kan H. Hor; Jason T. Su; Nathan Pack; Edward Dibella; William M. Gottliebson
The objective of this study was to examine RNA expression in blood of subjects with Duchenne muscular dystrophy (DMD). Whole\\u000a blood was collected into PAX gene tubes and RNA was isolated for 3- to 20-year-old males with DMD (n?=?34) and for age- and gender-matched normal healthy controls (n?=?21). DMD was confirmed by genetic testing in all subjects. RNA expression was
Brenda Wong; Donald L. Gilbert; Wynn L. Walker; Isaac H. Liao; Lisa Lit; Boryana Stamova; Glen Jickling; Michelle Apperson; Frank R. Sharp
Our Translational Gene Therapy Center has used small molecules for exon skipping and mutation suppression and gene transfer to replace or provide surrogate genes as tools for molecular-based approaches for the treatment of muscular dystrophies. Exon skipping is targeted at the pre-mRNA level allowing one or more exons to be omitted to restore the reading frame. In Duchenne Muscular Dystrophy (DMD), clinical trials have been performed with two different oligomers, a 2?O-methyl-ribo-oligonucleoside-phosphorothioate (2?OMe) and a phosphorodiamidate morpholino (PMO). Both have demonstrated early evidence of efficacy. A second molecular approach involves suppression of stop codons to promote readthrough of the DMD gene. We have been able to establish proof of principle for mutation suppression using the aminoglycoside, gentamicin. A safer, orally administered, alternative agent referred to as Ataluren (PTC124) has been used in clinical trials and is currently under consideration for approval by the FDA. Using a gene therapy approach, we have completed two trials and have initiated a third. For DMD, we used a mini-dystrophin transferred in adeno-associated virus (AAV). In this trial an immune response was seen directed against transgene product, a quite unexpected outcome that will help guide further studies. For limb girdle muscular dystrophy 2D (alpha-sarcoglycan deficiency), the transgene was again transferred using AAV but in this study, a muscle specific creatine kinase promoter controlled gene expression that persisted for six months. A third gene therapy trial has been initiated with transfer of the follistatin gene in AAV directly to the quadriceps muscle. Two diseases with selective quadriceps muscle weakness are undergoing gene transfer including sporadic inclusion body myositis (sIBM) and Becker muscular dystrophy (BMD). Increasing the size and strength of the muscle is the goal of this study. Most importantly, no adverse events have been encountered in any of these clinical trials.
Mendell, Jerry R.; Rodino-Klapac, Louise; Sahenk, Zarife; Malik, Vinod; Kaspar, Brian K.; Walker, Christopher M.; Clark, K. Reed
Pulmonary function was correlated with patient age and degree of thoracic scoliosis in 25 patients with Duchenne muscular dystrophy in a retrospective, longitudinal study. The observed forced vital capacity (FVC) was found to peak at approximately the age when standing ceases, then to decline rapidly. Thoracolumbar curves were found to be insignificant in adversely affecting pulmonary function in patients with Duchenne muscular dystrophy. Percent FVC was found to be the parameter of pulmonary function that was most strongly correlated with age and scoliosis measurements. In addition, age and thoracic scoliosis together were better predictors of percent FVC than either one alone. Each 1 year of age had approximately the same negative influence on percent FVC that each 10 degrees of thoracic scoliosis had; both decreased percent FVC by approximately 4%. A regression equation for percent FVC is presented which predicts that the patient who has had scoliosis progression halted by spinal fusion would, subsequent to the surgery, show a slower rate of decline of percent FVC and that this rate is quantifiable, predictable, and dependent solely on the patient's advancing age. Therefore, early spinal instrumentation and fusion is advocated in the patient with Duchenne muscular dystrophy. PMID:6874933
Kurz, L T; Mubarak, S J; Schultz, P; Park, S M; Leach, J
Duchenne muscular dystrophy is the most severe childhood form of muscular dystrophy caused by mutations in the gene responsible for dystrophin production. There is no cure, and treatment is limited to glucocorticoids that prolong ambulation and drugs to treat the cardiomyopathy. Multiple treatment strategies are under investigation and have shown promise for Duchenne muscular dystrophy. Use of molecular-based therapies that replace or correct the missing or nonfunctional dystrophin protein has gained momentum. These strategies include gene replacement with adeno-associated virus, exon skipping with antisense oligonucleotides, and mutation suppression with compounds that "read through" stop codon mutations. Other strategies include cell therapy and surrogate gene products to compensate for the loss of dystrophin. All of these approaches are discussed in this review, with particular emphasis on the most recent advances made in each therapeutic discipline. The advantages of each approach and challenges in translation are outlined in detail. Individually or in combination, all of these therapeutic strategies hold great promise for treatment of this devastating childhood disease. PMID:23328943
Rodino-Klapac, Louise R; Mendell, Jerry R; Sahenk, Zarife
Introduction: Disease inclusion in the newborn screening (NBS) panel should consider the opinions of those most affected by the outcome of screening. We assessed the level and factors that affect parent attitudes regarding NBS panel inclusion of Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and spinal muscular atrophy (SMA). Methods: The attitudes toward NBS for DMD, BMD, and SMA were surveyed and compared for 2 categories of parents, those with children affected with DMD, BMD, or SMA and expectant parents unselected for known family medical history. Results: The level of support for NBS for DMD, BMD, and SMA was 95.9% among parents of children with DMD, BMD, or SMA and 92.6% among expectant parents. Conclusions: There was strong support for NBS for DMD, BMD, and SMA in both groups of parents. Given advances in diagnostics and promising therapeutic approaches, discussion of inclusion in NBS should continue. Muscle Nerve 49: 822-828, 2014. PMID:24307279
Wood, Molly F; Hughes, Sarah C; Hache, Lauren P; Naylor, Edwin W; Abdel-Hamid, Hoda Z; Barmada, M Michael; Dobrowolski, Steven F; Stickler, David E; Clemens, Paula R
Muscular dystrophies are common, currently incurable diseases. A subset of dystrophies result from genetic disruptions in complexes that attach muscle fibers to their surrounding extracellular matrix microenvironment. Cell-matrix adhesions are exquisite sensors of physiological conditions and mediate responses that allow cells to adapt to changing conditions. Thus, one approach towards finding targets for future therapeutic applications is to identify cell adhesion pathways that mediate these dynamic, adaptive responses in vivo. We find that nicotinamide riboside kinase 2b-mediated NAD+ biosynthesis, which functions as a small molecule agonist of muscle fiber-extracellular matrix adhesion, corrects dystrophic phenotypes in zebrafish lacking either a primary component of the dystrophin-glycoprotein complex or integrin alpha7. Exogenous NAD+ or a vitamin precursor to NAD+ reduces muscle fiber degeneration and results in significantly faster escape responses in dystrophic embryos. Overexpression of paxillin, a cell adhesion protein downstream of NAD+ in this novel cell adhesion pathway, reduces muscle degeneration in zebrafish with intact integrin receptors but does not improve motility. Activation of this pathway significantly increases organization of laminin, a major component of the extracellular matrix basement membrane. Our results indicate that the primary protective effects of NAD+ result from changes to the basement membrane, as a wild-type basement membrane is sufficient to increase resilience of dystrophic muscle fibers to damage. The surprising result that NAD+ supplementation ameliorates dystrophy in dystrophin-glycoprotein complex- or integrin alpha7-deficient zebrafish suggests the existence of an additional laminin receptor complex that anchors muscle fibers to the basement membrane. We find that integrin alpha6 participates in this pathway, but either integrin alpha7 or the dystrophin-glycoprotein complex is required in conjunction with integrin alpha6 to reduce muscle degeneration. Taken together, these results define a novel cell adhesion pathway that may have future therapeutic relevance for a broad spectrum of muscular dystrophies. PMID:23109907
Goody, Michelle F; Kelly, Meghan W; Reynolds, Christine J; Khalil, Andre; Crawford, Bryan D; Henry, Clarissa A
Muscular dystrophies are common, currently incurable diseases. A subset of dystrophies result from genetic disruptions in complexes that attach muscle fibers to their surrounding extracellular matrix microenvironment. Cell-matrix adhesions are exquisite sensors of physiological conditions and mediate responses that allow cells to adapt to changing conditions. Thus, one approach towards finding targets for future therapeutic applications is to identify cell adhesion pathways that mediate these dynamic, adaptive responses in vivo. We find that nicotinamide riboside kinase 2b-mediated NAD+ biosynthesis, which functions as a small molecule agonist of muscle fiber-extracellular matrix adhesion, corrects dystrophic phenotypes in zebrafish lacking either a primary component of the dystrophin-glycoprotein complex or integrin alpha7. Exogenous NAD+ or a vitamin precursor to NAD+ reduces muscle fiber degeneration and results in significantly faster escape responses in dystrophic embryos. Overexpression of paxillin, a cell adhesion protein downstream of NAD+ in this novel cell adhesion pathway, reduces muscle degeneration in zebrafish with intact integrin receptors but does not improve motility. Activation of this pathway significantly increases organization of laminin, a major component of the extracellular matrix basement membrane. Our results indicate that the primary protective effects of NAD+ result from changes to the basement membrane, as a wild-type basement membrane is sufficient to increase resilience of dystrophic muscle fibers to damage. The surprising result that NAD+ supplementation ameliorates dystrophy in dystrophin-glycoprotein complex– or integrin alpha7–deficient zebrafish suggests the existence of an additional laminin receptor complex that anchors muscle fibers to the basement membrane. We find that integrin alpha6 participates in this pathway, but either integrin alpha7 or the dystrophin-glycoprotein complex is required in conjunction with integrin alpha6 to reduce muscle degeneration. Taken together, these results define a novel cell adhesion pathway that may have future therapeutic relevance for a broad spectrum of muscular dystrophies.
Goody, Michelle F.; Kelly, Meghan W.; Reynolds, Christine J.; Khalil, Andre; Crawford, Bryan D.; Henry, Clarissa A.
Mutations in the dysferlin gene lead to limb girdle muscular dystrophy 2B, Miyoshi myopathy and distal anterior compartment myopathy. A cohort of 36 patients affected by dysferlinopathy is described, in the first UK study of clinical, genetic, pathological and biochemical data. The diagnosis was established by reduction of dysferlin in the muscle biopsy and subsequent mutational analysis of the dysferlin gene. Seventeen mutations were novel; the majority of mutations were small deletions/insertions, and no mutational hotspots were identified. Sixty-one per cent of patients (22 patients) initially presented with limb girdle muscular dystrophy 2B, 31% (11 patients) with a Miyoshi phenotype, one patient with proximodistal mode of onset, one patient with muscle stiffness after exercise and one patient as a symptomatic carrier. A wider range of age of onset was noted than previously reported, with 25% of patients having first symptoms before the age of 13 years. Independent of the initial mode of presentation, in our cohort of patients the gastrocnemius muscle was the most severely affected muscle leading to an inability to stand on tiptoes, and lower limbs were affected more severely than upper limbs. As previous anecdotal evidence on patients affected by dysferlinopathy suggests good muscle prowess before onset of symptoms, we also investigated pre-symptomatic fitness levels of the patients. Fifty-three per cent of the patients were very active and sporty before the onset of symptoms which makes the clinical course of dysferlinopathy unusual within the different forms of muscular dystrophy and provides a challenge to understanding the underlying pathomechanisms in this disease. PMID:19528035
Klinge, Lars; Aboumousa, Ahmed; Eagle, Michelle; Hudson, Judith; Sarkozy, Anna; Vita, Gianluca; Charlton, Richard; Roberts, Mark; Straub, Volker; Barresi, Rita; Lochmüller, Hanns; Bushby, Kate
Halofuginone has been shown to prevent fibrosis via the transforming growth factor-?/Smad3 pathway in muscular dystrophies. We hypothesized that halofuginone would reduce apoptosis--the presumed cause of satellite-cell depletion during muscle degradation-in the mdx mouse model of Duchenne muscular dystrophy. Six-week-old mdx mouse diaphragm exhibited fourfold higher numbers of apoptotic nuclei compared with wild-type mice as determined by a TUNEL assay. Apoptotic nuclei were found in macrophages and in Pax7-expressing cells; some were located in centrally-nucleated regenerating myofibers. Halofuginone treatment of mdx mice reduced the apoptotic nuclei number in the diaphragm, together with reduction in Bax and induction in Bcl2 levels in myofibers isolated from these mice. A similar effect was observed when halofuginone was added to cultured myofibers. No apparent effect of halofuginone was observed in wild-type mice. Inhibition of apoptosis or staurosporine-induced apoptosis by halofuginone in mdx primary myoblasts and C2 myogenic cell line, respectively, was reflected by less pyknotic/apoptotic cells and reduced Bax expression. This reduction was reversed by a phosphinositide-3-kinase and mitogen-activated protein kinase/extracellular signal-regulated protein kinase inhibitors, suggesting involvement of these pathways in mediating halofuginone's effects on apoptosis. Halofuginone increased apoptosis in ? smooth muscle actin- and prolyl 4-hydroxylase ?-expressing cells in mdx diaphragm and in myofibroblasts, the major source of extracellular matrix. The data suggest an additional mechanism by which halofuginone improves muscle pathology and function in muscular dystrophies. PMID:24703880
Bodanovsky, Anna; Guttman, Noga; Barzilai-Tutsch, Hila; Genin, Ola; Levy, Oshrat; Pines, Mark; Halevy, Orna
Dysferlin is the protein product of the DYSF gene mapped at 2p31, which mutations cause limb-girdle muscular dystrophy type\\u000a 2B (LGMD2B) and Miyoshi myopathy. To date, nine autosomal recessive forms (AR-LGMD) have been identified: four genes, which\\u000a code for the sarcoglycan glycoproteins, are associated with both mild and severe forms, the sarcoglycanopathies (LGMD2C, 2D,\\u000a 2E and 2F). The other five
Mariz Vainzof; Louise V. B. Anderson; Elizabeth M. McNally; Dawn B. Davis; Georgine Faulkner; Giorgio Valle; Eloisa S. Moreira; Rita C. M. Pavanello; Maria Rita Passos-Bueno; Mayana Zatz
Multipotent cells that can give rise to bone, cartilage, fat, connective tissue, skeletal and cardiac muscle are termed mesenchymal stem cells (MSCs). These cells were first identified in the bone marrow, distinct from blood-forming stem cells. Based on the embryologic derivation, availability, and various pro-regenerative characteristics, research exploring their use in cell therapy shows great promise for patients with degenerative muscle diseases and a number of other conditions. In this review, the authors explore the potential for MSC therapy in the emerging field of regenerative medicine with a focus on treatment for Duchenne muscular dystrophy (DMD).
Markert, Chad; Atala, Anthony; Cann, Jennifer K.; Christ, George; Furth, Mark; Ambrosio, Fabrisia; Childers, Martin K.
We report the first case of Leigh syndrome (LS) with Fukuyama congenital muscular dystrophy (FCMD). A neonate suffered from lactic acidosis and subsequently presented with poor feeding, muscle weakness, hypotonia, cardiopulmonary dysfunction, and hydrocephalus. He died at 17months. The findings of brain magnetic resonance imaging indicated some specific features of both LS and FCMD, and FCMD gene mutation was detected. Decreased mitochondrial respiratory complex I and II activity was noted. Mitochondrial DNA sequencing showed no pathogenic mutation. A case with complex I+II deficiency has rarely been reported, suggesting a nuclear gene mutation. PMID:24113355
Kondo, Hidehito; Tanda, Koichi; Tabata, Chihiro; Hayashi, Kohei; Kihara, Minako; Kizaki, Zenro; Taniguchi-Ikeda, Mariko; Mori, Masato; Murayama, Kei; Ohtake, Akira
Although prednisone has never been formally approved for use in Duchenne muscular dystrophy (DMD) by regulatory agencies, its efficacy has been confirmed in trials dating from the 1980s. There is a strong need for optimization of both specific type of glucocorticoid (eg, prednisone, vs deflazacort or others) and the dosing regimen. Ideally an optimized regimen would maximize efficacy while minimizing side-effect profiles. A new trial, FOR-DMD, aims to address this gap in knowledge. In parallel, there has been progress in the area of "dissociative steroids," drugs that are able to better separate efficacy and side effects, providing a broader therapeutic window. PMID:23137739
Hoffman, Eric P; Reeves, Erica; Damsker, Jesse; Nagaraju, Kanneboyina; McCall, John M; Connor, Edward M; Bushby, Kate
In a previous study we identified 14 cases with Duchenne muscular dystrophy (DMD) or its milder variant, Becker muscular dystrophy (BMD), with a deletion of exons 3-7, a deletion that would be expected to shift the translational reading frame of the mRNA and give a severe phenotype. We have examined dystrophin and its mRNA from muscle biopsies of seven cases with either mild or intermediate phenotypes. In all cases we detected slightly lower-molecular-weight dystrophin in 12%-15% abudance relative to the normal. By sequencing amplified mRNA we have found that exon 2 is spliced to exon 8, a splice that produces a frameshifted mRNA, and have found no evidence for alternative splicing that might be involved in restoration of dystrophin mRNA reading frame in the patients with a mild phenotype. Other transcriptional and posttranscriptional mechanisms such as cryptic promoter, ribosomal frameshifting, and reinitiation are suggested that might play some role in restoring the reading frame. Images Figure 1 Figure 2 Figure 3 Figure 4
Gangopadhyay, S B; Sherratt, T G; Heckmatt, J Z; Dubowitz, V; Miller, G; Shokeir, M; Ray, P N; Strong, P N; Worton, R G
Monozygotic twin girls are reported, one of whom has the typical clinical features of Duchenne muscular dystrophy despite a normal female karyotype. Although certain features of the biopsy were atypical, the clinical diagnosis was supported by persistent markedly raised blood creatine kinase levels and findings typical of DMD on electromyography and magnetic resonance spectroscopy. Analysis of an X linked DNA polymorphism in 16 independent somatic cell hybrids made between cells derived from each girl and a mouse line suggest that in one twin only the maternal X chromosome is active, whereas in the other the active X was paternally derived. More data are needed to exclude sampling error. These preliminary experimental results support the hypothesis that both girls are heterozygous for Duchenne muscular dystrophy. X inactivation, by chance, resulted in two contrasting cell masses with different active X chromosomes. This segregation was followed by, and may even have resulted in, twinning into a female pair, one normal and one with the full clinical features of the disease. Images
Burn, J; Povey, S; Boyd, Y; Munro, E A; West, L; Harper, K; Thomas, D
The alpha-dystroglycanopathies are genetically heterogeneous muscular dystrophies that result from hypoglycosylation of alpha-dystroglycan (?-DG). Alpha-dystroglycan is an essential link between the extracellular matrix and the muscle fiber sarcolemma, and proper glycosylation is critical for its ability to bind to ligands in the extracellular matrix. We sought to identify the genetic basis of alpha-dystroglycanopathy in a family wherein the affected individuals presented with congenital muscular dystrophy, brain abnormalities and generalized epilepsy. We performed whole exome sequencing and identified compound heterozygous GMPPB mutations in the affected children. GMPPB is an enzyme in the glycosylation pathway, and GMPPB mutations were recently linked to eight cases of alpha-dystroglycanopathy with a range of symptoms. We identified a novel mutation in GMPPB (p.I219T) as well as a previously published mutation (p.R287Q). Thus, our work further confirms a role for GMPPB defects in alpha-dystroglycanopathy, and suggests that glycosylation may play a role in the neuronal membrane channels or networks involved in the physiology of generalized epilepsy syndromes. This article is part of a Special Issue entitled RNA Metabolism 2013. PMID:24780531
Raphael, Alya R; Couthouis, Julien; Sakamuri, Sarada; Siskind, Carly; Vogel, Hannes; Day, John W; Gitler, Aaron D
A resolutive therapy for Duchene muscular dystrophy, a severe degenerative disease of the skeletal muscle, is still lacking. Because autophagy has been shown to be crucial in clearing dysfunctional organelles and in preventing tissue damage, we investigated its pathogenic role and its suitability as a target for new therapeutic interventions in Duchenne muscular dystrophy (DMD). Here we demonstrate that autophagy is severely impaired in muscles from patients affected by DMD and mdx mice, a model of the disease, with accumulation of damaged organelles. The defect in autophagy was accompanied by persistent activation via phosphorylation of Akt, mammalian target of rapamycin (mTOR) and of the autophagy-inhibiting pathways dependent on them, including the translation-initiation factor 4E-binding protein 1 and the ribosomal protein S6, and downregulation of the autophagy-inducing genes LC3, Atg12, Gabarapl1 and Bnip3. The defective autophagy was rescued in mdx mice by long-term exposure to a low-protein diet. The treatment led to normalisation of Akt and mTOR signalling; it also reduced significantly muscle inflammation, fibrosis and myofibre damage, leading to recovery of muscle function. This study highlights novel pathogenic aspects of DMD and suggests autophagy as a new effective therapeutic target. The treatment we propose can be safely applied and immediately tested for efficacy in humans. PMID:23152054
De Palma, C; Morisi, F; Cheli, S; Pambianco, S; Cappello, V; Vezzoli, M; Rovere-Querini, P; Moggio, M; Ripolone, M; Francolini, M; Sandri, M; Clementi, E
The identification of the Duchenne muscular dystrophy gene and protein in the late 1980s led to high hopes of rapid translation to molecular therapeutics. These hopes were fueled by early reports of delivering new functional genes to dystrophic muscle in mouse models using gene therapy and stem cell transplantation. However, significant barriers have thwarted translation of these approaches to true therapies, including insufficient therapeutic material (eg, cells and viral vectors), challenges in systemic delivery, and immunological hurdles. An alternative approach is to repair the patient's own gene. Two innovative small-molecule approaches have emerged as front-line molecular therapeutics: exon skipping and stop codon read through. Both approaches are in human clinical trials and aim to coax dystrophin protein production from otherwise inactive mutant genes. In the clinically severe dog model of Duchenne muscular dystrophy, the exon-skipping approach recently improved multiple functional outcomes. We discuss the status of these two methods aimed at inducing de novo dystrophin production from mutant genes and review implications for other disorders.
Hoffman, Eric P.; Bronson, Abby; Levin, Arthur A.; Takeda, Shin'ichi; Yokota, Toshifumi; Baudy, Andreas R.; Connor, Edward M.
Extraocular muscles are generally considered to be spared in Duchenne Muscular Dystrophy (DMD). However, this assumption is based mainly on clinical observations, as systematic eye movement recordings have been performed in a very limited number of cases. Our goal was to analyze several saccade parameters in a higher number of cases, in order to reveal a possible ocular-motor impairment in DMD. Data were collected from a population of 9 subjects with DMD and 9 healthy male subjects of comparable age as controls. We used the electrooculographic (EOG) technique coupled with advanced digital signal processing; saccade duration, amplitude, mean velocity, peak velocity and K factor (ratio mean/peak velocity) were measured. The DMD group showed saccades with significantly longer duration and lower velocity, with respect to controls; these differences were accounted for mainly by the largest movements, whereas there were no significant differences at the smallest eccentricity tested (3 deg). Neither amplitude nor K factor were significantly different from controls for any of the eccentricities tested. To our knowledge. this is the first study to suggest significant impairment of eye movements in Duchenne muscular dystrophy. PMID:11824659
Lui, F; Fonda, S; Merlini, L; Corazza, R
A resolutive therapy for Duchene muscular dystrophy, a severe degenerative disease of the skeletal muscle, is still lacking. Because autophagy has been shown to be crucial in clearing dysfunctional organelles and in preventing tissue damage, we investigated its pathogenic role and its suitability as a target for new therapeutic interventions in Duchenne muscular dystrophy (DMD). Here we demonstrate that autophagy is severely impaired in muscles from patients affected by DMD and mdx mice, a model of the disease, with accumulation of damaged organelles. The defect in autophagy was accompanied by persistent activation via phosphorylation of Akt, mammalian target of rapamycin (mTOR) and of the autophagy-inhibiting pathways dependent on them, including the translation-initiation factor 4E-binding protein 1 and the ribosomal protein S6, and downregulation of the autophagy-inducing genes LC3, Atg12, Gabarapl1 and Bnip3. The defective autophagy was rescued in mdx mice by long-term exposure to a low-protein diet. The treatment led to normalisation of Akt and mTOR signalling; it also reduced significantly muscle inflammation, fibrosis and myofibre damage, leading to recovery of muscle function. This study highlights novel pathogenic aspects of DMD and suggests autophagy as a new effective therapeutic target. The treatment we propose can be safely applied and immediately tested for efficacy in humans.
De Palma, C; Morisi, F; Cheli, S; Pambianco, S; Cappello, V; Vezzoli, M; Rovere-Querini, P; Moggio, M; Ripolone, M; Francolini, M; Sandri, M; Clementi, E
BACKGROUND: In Duchenne muscular dystrophy (DMD), the muscular degeneration often leads to the development of scoliosis. Our objective was to investigate how anatomical changes in back muscles can lead to scoliosis. Muscular volume and the level of fat infiltration in those muscles were thus evaluated, in non-scoliotic, pre-scoliotic and scoliotic patients. The overlying skin thickness over the apex level of
Gnahoua Zoabli; Pierre A Mathieu; Carl-Éric Aubin
The Muscular Dystrophy Surveillance Tracking and Research Network (MD STARnet) is a multisite collaboration to determine the prevalence of childhood-onset Duchenne/Becker muscular dystrophy and to characterize health care and health outcomes in this population. MD STARnet uses medical record abstraction to identify patients with Duchenne/Becker muscular dystrophy born January 1, 1982 or later who resided in one of the participating sites. Critical diagnostic elements of each abstracted record are reviewed independently by ?4 clinicians and assigned to 1 of 6 case definition categories (definite, probable, possible, asymptomatic, female, not Duchenne/Becker muscular dystrophy) by consensus. As of November 2009, 815 potential cases were reviewed. Of the cases included in analysis, 674 (82%) were either “definite” or “probable” Duchenne/Becker muscular dystrophy. These data reflect a change in diagnostic testing, as case assignment based on genetic testing increased from 67% in the oldest cohort (born 1982–1987) to 94% in the cohort born 2004–2009.
Mathews, Katherine D.; Cunniff, Chris; Kantamneni, Jiji R.; Ciafaloni, Emma; Miller, Timothy; Matthews, Dennis; Cwik, Valerie; Druschel, Charlotte; Miller, Lisa; Meaney, F. John; Sladky, John; Romitti, Paul A.
A protocol for the evaluation of functional activities in subjects with Duchenne muscular dystrophy (DMD) was designed. The aim of our study was to define objective clinical criteria for the evaluation both of the clinical status of the patient and of the natural history of the illness itself. A protocol with such criteria is particularly necessary when testing the efficacy of treatment. 43 still-ambulant children with DMD between the ages of 3.10 yr and 10.4 yr were examined. Of this number 19 children were evaluated every 4 months over a period of 12 months; of these 14 formed part of a randomized double blind trial with L-carnitine (1.2-1.8 g/day) versus placebo. PMID:6762370
Cornelio, F; Dworzak, F; Morandi, L; Fedrizzi, E; Balestrini, M R; Gondoni, L
Poor bone health is a significant problem for patients with Duchenne muscular dystrophy (DMD), a progressive, disabling disease. Although the primary focus of DMD disease pathogenesis is degeneration of striated muscle, impairment of bone health likely has a role in the disease that has only been superficially examined to date. Deficiency of bone mineral density and increased incidence of bone fractures are well-recognized clinical components of the DMD phenotype. Furthermore, therapy with corticosteroids, an approved treatment for DMD that prolongs ambulation, may have multiple effects on bone health in DMD patients. This review examines the evidence in preclinical models and in human DMD disease that provides insight into the role performed by bone in the disease pathogenesis and phenotype of DMD. The information reviewed here points toward the need for mechanistic and therapeutic studies to optimize bone health in DMD patients.
Morgenroth, Victor H; Hache, Lauren P; Clemens, Paula R
In extracts derived from whole blood, a high molecular weight fraction of the diphenoloxidase enzymes has a significantly diminished specific activity in patients and definite carriers (heterozygotes) of the X-linked, recessive (Duchenne) form of muscular dystrophy. This anomaly was studied using spots of blood which had been collected on absorbent paper and stored at 4 degrees C for variable periods of time. Fractions enriched in the enzymes were obtained by subjecting aqueous extracts of the spots to treatment with an anion exchange resin (DEAE Sephadex A 50) followed by gel filtration on Sephadex G-25. It is of interest that this anomaly was observed in some definite carriers of the mutant gene who had on several occasions a serum creatine kinase level in the normal range. The significance of these observations is discussed. PMID:6799386
Demos, J J; Tuil, D G; Katz, P C; Berthelon, M A; Dautreaux, B; Premont, N
This article investigates the relationships of child- and family-related variables with family function in families with children who have Duchenne muscular dystrophy. Child-related variables included level of disability (indicator: Barthel Index) and age at diagnosis. Family-related variables included caregiver health status (indicator: Duke Health Profile), family income and employment, family support (indicator: Family APGAR), family hardiness (indicator: Family Hardiness Index), and family functioning (indicator: Family Assessment Device). Family function displayed a significant correlation with age at diagnosis, but not with disability level. It was also significantly correlated with family hardiness, caregiver health status, and levels of family support, but not with income or employment variables. These findings highlight the need to assist families to cope with the presence of serious illness in their children. PMID:17873636
Chen, Jih-Yuan; Clark, Mary-Jo
This work is based on 54 probands affected by oculopharyngeal muscular dystrophy (OPMD). The muscle biopsy of all these patients showed the presence of the intranuclear inclusions, specific of this disease. The residence of the probands is concentrated in three clusters: the Paris, Marseilles and Bordeaux regions. The genealogical study was carried out on 43 probands, 10 of which did not have any ascendance in France for more than two generations. The geographic origin of the 33 patients of French descent was distributed over numerous regions, not including the Paris and Marseilles regions where many patients lived. This geographic dispersion and the rarity of common genealogies of the probands, did not suggest the existence of a recent founder effect, in contrast to what is observed in the French-Canadian community. The existence of a link between French and French-Canadian families is currently being investigated. PMID:9392013
Brunet, G; Tomé, F M; Eymard, B; Robert, J M; Fardeau, M
Fibrosis is the aberrant deposition of extracellular matrix (ECM) components during tissue healing leading to loss of its architecture and function. Fibrotic diseases are often associated with chronic pathologies and occur in a large variety of vital organs and tissues, including skeletal muscle. In human muscle, fibrosis is most readily associated with the severe muscle wasting disorder Duchenne muscular dystrophy (DMD), caused by loss of dystrophin gene function. In DMD, skeletal muscle degenerates and is infiltrated by inflammatory cells and the functions of the muscle stem cells (satellite cells) become impeded and fibrogenic cells hyperproliferate and are overactivated, leading to the substitution of skeletal muscle with nonfunctional fibrotic tissue. Here, we review new developments in our understanding of the mechanisms leading to fibrosis in DMD and several recent advances towards reverting it, as potential treatments to attenuate disease progression.
Kharraz, Yacine; Guerra, Joana; Serrano, Antonio L.; Munoz-Canoves, Pura
Introduction The multitude of symptoms associated with facioscapulohumeral muscular dystrophy (FSHD) disease burden are of varying importance. The extent of these symptoms and their cumulative effect on the FSHD population is unknown. Methods We conducted interviews with adult FSHD patients to identify which symptoms have the greatest effect on their lives. Each interview was recorded, transcribed, coded, and analyzed using a qualitative framework technique, triangulation, and 3-investigator consensus approach. Results 1375 quotes were obtained through 20 patient interviews. 251 symptoms of importance were identified representing 14 themes of FSHD disease burden. Symptoms associated with mobility impairment, activity limitation, and social role limitation were most frequently mentioned by participants. Conclusions There are multiple themes and symptoms, some previously under-recognized, that play a key role in FSHD disease burden.
Johnson, Nicholas E; Quinn, Christine; Eastwood, Eileen; Tawil, Rabi; Heatwole, Chad R
Though Deflazacort and prednisone improve clinical endpoints in Duchenne muscular dystrophy (DMD) patients, Deflazacort produces fewer side effects. As mechanisms of improvement and side effect differences remain unknown, we evaluated effects of corticosteroid administration on gene expression in blood of DMD patients. Whole blood was obtained from 14 children and adolescents with DMD treated with corticosteroids (DMD-STEROID) and 20 DMD children and adolescents naïve to corticosteroids (DMD). The DMD-STEROID group was further subdivided into Deflazacort and prednisone groups. Affymetrix U133 Plus 2.0 expression microarrays were used to evaluate mRNA expression. Expression of 524 probes changed with corticosteroids, including genes in iron trafficking and the chondroitin sulfate biosynthesis pathway. Deflazacort compared with prednisone yielded 508 regulated probes, including many involved in adipose metabolism. These genes and pathways help explain mechanisms of efficacy and side effects of corticosteroids, and could provide new treatment targets for DMD and other neuromuscular disorders. PMID:19488064
Lit, L; Sharp, F R; Apperson, M; Liu, D Z; Walker, W L; Liao, I; Xu, H; Ander, B P; Wong, B
The aim of this study was to analyze previously published gene expression data of skeletal muscle biopsies of Duchenne muscular dystrophy (DMD) patients and controls (gene expression omnibus database, accession #GSE6011) using systems biology approaches. We applied an unsupervised method to discriminate patient and control populations, based on principal component analysis, using the gene expressions as units and patients as variables. The genes having the highest absolute scores in the discrimination between the groups, were then analyzed in terms of gene expression networks, on the basis of their mutual correlation in the two groups. The correlation network structures suggest two different modes of gene regulation in the two groups, reminiscent of important aspects of DMD pathogenesis. PMID:23929863
Bernardini, Camilla; Censi, Federica; Lattanzi, Wanda; Calcagnini, Giovanni; Giuliani, Alessandro
Becker muscular dystrophy (BMD) is a progressive X-linked muscle wasting disease for which there is no treatment. Like Duchenne muscular dystrophy (DMD), BMD is caused by mutations in the gene encoding dystrophin, a structural cytoskeletal protein that also targets other proteins to the muscle sarcolemma. Among these is neuronal nitric oxide synthase (nNOS?), which requires certain spectrin-like repeats in dystrophin’s rod domain and the adaptor protein ?-syntrophin to be targeted to the sarcolemma. When healthy skeletal muscle is subjected to exercise, sarcolemmal nNOS?-derived nitric oxide (NO) attenuates local ?-adrenergic vasoconstriction thereby optimizing perfusion of muscle. We found previously that this protective mechanism is defective—causing functional muscle ischemia—in dystrophin-deficient muscles of the mdx mouse (a model of DMD) and of children with DMD, in whom nNOS? is mislocalized to the cytosol instead of the sarcolemma. Here, we report that this protective mechanism also is defective in men with BMD in whom the most common dystrophin mutations disrupt sarcolemmal targeting of nNOS?. In these men, the vasoconstrictor response, measured as a decrease in muscle oxygenation, to reflex sympathetic activation is not appropriately attenuated during exercise of the dystrophic muscles. In a randomized placebo-controlled cross-over trial, we show that functional muscle ischemia is alleviated and normal blood flow regulation fully restored in the muscles of men with BMD by boosting NO-cGMP signaling with a single dose of the drug tadalafil, a phosphodiesterase (PDE5A) inhibitor. These results further support an essential role for sarcolemmal nNOS? in the normal modulation of sympathetic vasoconstriction in exercising human skeletal muscle and implicate the NO-cGMP pathway as a putative new target for treating BMD.
Martin, Elizabeth A.; Barresi, Rita; Byrne, Barry J.; Tsimerinov, Evgeny I.; Scott, Bryan L.; Walker, Ashley E.; Gurudevan, Swaminatha V.; Anene, Francine; Elashoff, Robert M.; Thomas, Gail D.; Victor, Ronald G.
Becker muscular dystrophy (BMD) is a progressive X-linked muscle wasting disease for which there is no treatment. Like Duchenne muscular dystrophy (DMD), BMD is caused by mutations in the gene encoding dystrophin, a structural cytoskeletal protein that also targets other proteins to the muscle sarcolemma. Among these is neuronal nitric oxide synthase (nNOS?), which requires certain spectrin-like repeats in dystrophin's rod domain and the adaptor protein ?-syntrophin to be targeted to the sarcolemma. When healthy skeletal muscle is subjected to exercise, sarcolemmal nNOS?-derived NO attenuates local ?-adrenergic vasoconstriction, thereby optimizing perfusion of muscle. We found previously that this protective mechanism is defective-causing functional muscle ischemia-in dystrophin-deficient muscles of the mdx mouse (a model of DMD) and of children with DMD, in whom nNOS? is mislocalized to the cytosol instead of the sarcolemma. We report that this protective mechanism also is defective in men with BMD in whom the most common dystrophin mutations disrupt sarcolemmal targeting of nNOS?. In these men, the vasoconstrictor response, measured as a decrease in muscle oxygenation, to reflex sympathetic activation is not appropriately attenuated during exercise of the dystrophic muscles. In a randomized placebo-controlled crossover trial, we show that functional muscle ischemia is alleviated and normal blood flow regulation is fully restored in the muscles of men with BMD by boosting NO-cGMP (guanosine 3',5'-monophosphate) signaling with a single dose of the drug tadalafil, a phosphodiesterase 5A inhibitor. These results further support an essential role for sarcolemmal nNOS? in the normal modulation of sympathetic vasoconstriction in exercising human skeletal muscle and implicate the NO-cGMP pathway as a putative new target for treating BMD. PMID:23197572
Martin, Elizabeth A; Barresi, Rita; Byrne, Barry J; Tsimerinov, Evgeny I; Scott, Bryan L; Walker, Ashley E; Gurudevan, Swaminatha V; Anene, Francine; Elashoff, Robert M; Thomas, Gail D; Victor, Ronald G
Facioscapulohumeral muscular dystrophy is an autosomal dominant muscle disorder, mapped to 4q35. It is characterized by remarkable inter- and intrafamilial clinical variability ranging from severe phenotype to asymptomatic carriers. The aim of the present study was to assess the size of the Eco RI fragment in a large sample of asymptomatic or minimally affected carriers as well as symptomatic patients, comparing both sexes, in order to verify if asymptomatic carriers are randomly distributed or concentrated in some particular families and if there is preferential parental transmission (maternal or paternal) resulting in non-penetrant carriers. We have analysed a total of 506 individuals from 106 unrelated families with at least one affected facioscapulohumeral muscular dystrophy proband. In all patients the molecular diagnosis was confirmed following double digestion (Eco RI/Bln I fragment <35 kb). About 20% among probands' relatives who were found to carry the small fragment were asymptomatic or minimally affected, without preferential parental transmission, but with a significantly higher proportion of females (n=37) than males (n=14). Although asymptomatic carriers were found in about 30% of the families, some genealogies seem to concentrate more non-penetrant cases. A significant correlation between the size of the Eco RI fragment and severity of the phenotype was observed in the total sample but surprisingly this correlation is significant only among affected females. The gender difference in clinical manifestation as well as the observation that asymptomatic carriers are not rare should be taken into consideration in genetic counseling of affected patients or 'at-risk' relatives. PMID:14659410
Tonini, M M O; Passos-Bueno, M R; Cerqueira, A; Matioli, S R; Pavanello, R; Zatz, M
OBJECTIVE To study the order and degree of muscular affection in patients with Duchenne muscular dystrophy (DMD) during the course of disease. METHODS Multiplex ligation dependent probe amplification (MLPA) was used to detect potential mutation of dystrophin gene. Magnetic resonance imaging (MRI) was used to scan the anteromedial aspect of thigh muscles. RESULTS All of the 6 patients were found to have deletion or duplication mutations. The order of affection has been gluteus maximus, adductor magnus, quadriceps femoris, rectus femoris and biceps muscle of the thigh, while semimembranous muscle, semitendinosus, sartorius muscle and musculus gracilis are selectively affected and in a decreasing order. CONCLUSION MRI can reflect the order, extent and degree of skeletal muscle involvement in patients with DMD, and can reflect pathological changes of damaged skeletal muscle at each stage, which may provide an important means for patient examination and diagnosis. No apparent correlation between the severity of disease and the nature of mutations was noted. PMID:24928023
Chen, Wei; Feng, Shanwei; Feng, Huiyu; Zhang, Cheng
The study concerns 77 adults with muscular dystrophy (mean age 49 years) in two counties in Sweden. The purpose was to investigate activities of daily living, quality of life and the relationship between these. Data collection was per- formed with \\
Birgitta NaÈ tterlund
Duchenne muscular dystrophy (DMD) is a lethal X-linked disorder caused by mutations in the dystrophin gene, which encodes a cytoskeletal protein, dystrophin. Creatine kinase (CK) is generally used as a blood-based biomarker for muscular disease including DMD, but it is not always reliable since it is easily affected by stress to the body, such as exercise. Therefore, more reliable biomarkers of muscular dystrophy have long been desired. MicroRNAs (miRNAs) are small, ?22 nucleotide, noncoding RNAs which play important roles in the regulation of gene expression at the post-transcriptional level. Recently, it has been reported that miRNAs exist in blood. In this study, we hypothesized that the expression levels of specific serum circulating miRNAs may be useful to monitor the pathological progression of muscular diseases, and therefore explored the possibility of these miRNAs as new biomarkers for muscular diseases. To confirm this hypothesis, we quantified the expression levels of miRNAs in serum of the dystrophin-deficient muscular dystrophy mouse model, mdx, and the canine X-linked muscular dystrophy in Japan dog model (CXMDJ), by real-time PCR. We found that the serum levels of several muscle-specific miRNAs (miR-1, miR-133a and miR-206) are increased in both mdx and CXMDJ. Interestingly, unlike CK levels, expression levels of these miRNAs in mdx serum are little influenced by exercise using treadmill. These results suggest that serum miRNAs are useful and reliable biomarkers for muscular dystrophy.
Mizuno, Hideya; Nakamura, Akinori; Aoki, Yoshitsugu; Ito, Naoki; Kishi, Soichiro; Yamamoto, Kazuhiro; Sekiguchi, Masayuki; Takeda, Shin'ichi; Hashido, Kazuo
Duchenne muscular dystrophy is caused by mutations in the DMD gene that disrupt the open reading frame and prevent the full translation of its protein product, dystrophin. Restoration of the open reading frame and dystrophin production can be achieved by exon skipping using antisense oligonucleotides targeted to splicing elements. This approach aims to transform the Duchenne muscular dystrophy phenotype to that of the milder disorder, Becker muscular dystrophy, typically caused by in-frame dystrophin deletions that allow the production of an internally deleted but partially functional dystrophin. There is ongoing debate regarding the functional properties of the different internally deleted dystrophins produced by exon skipping for different mutations; more insight would be valuable to improve and better predict the outcome of exon skipping clinical trials. To this end, we have characterized the clinical phenotype of 17 patients with Becker muscular dystrophy harbouring in-frame deletions relevant to on-going or planned exon skipping clinical trials for Duchenne muscular dystrophy and correlated it to the levels of dystrophin, and dystrophin-associated protein expression. The cohort of 17 patients, selected exclusively on the basis of their genotype, included 4 asymptomatic, 12 mild and 1 severe patient. All patients had dystrophin levels of >40% of control and significantly higher dystrophin (P?=?0.013), ?-dystroglycan (P?=?0.025) and neuronal nitric oxide synthase (P?=?0.034) expression was observed in asymptomatic individuals versus symptomatic patients with Becker muscular dystrophy. Furthermore, grouping the patients by deletion, patients with Becker muscular dystrophy with deletions with an end-point of exon 51 (the skipping of which could rescue the largest group of Duchenne muscular dystrophy deletions) showed significantly higher dystrophin levels (P?=?0.034) than those with deletions ending with exon 53. This is the first quantitative study on both dystrophin and dystrophin-associated protein expression in patients with Becker muscular dystrophy with deletions relevant for on-going exon skipping trials in Duchenne muscular dystrophy. Taken together, our results indicate that all varieties of internally deleted dystrophin assessed in this study have the functional capability to provide a substantial clinical benefit to patients with Duchenne muscular dystrophy.
Anthony, Karen; Cirak, Sebahattin; Torelli, Silvia; Tasca, Giorgio; Feng, Lucy; Arechavala-Gomeza, Virginia; Armaroli, Annarita; Guglieri, Michela; Straathof, Chiara S.; Verschuuren, Jan J.; Aartsma-Rus, Annemieke; Helderman-van den Enden, Paula; Bushby, Katherine; Straub, Volker; Sewry, Caroline; Ferlini, Alessandra; Ricci, Enzo; Morgan, Jennifer E.
Albeit genetically highly heterogeneous, muscular dystrophies (MDs) share a convergent pathology leading to muscle wasting accompanied by proliferation of fibrous and fatty tissue, suggesting a common MD–pathomechanism. Here we show that mutations in muscular dystrophy genes (Dmd, Dysf, Capn3, Large) lead to the spontaneous formation of skeletal muscle-derived malignant tumors in mice, presenting as mixed rhabdomyo-, fibro-, and liposarcomas. Primary
Wolfgang M. Schmidt; Mohammed H. Uddin; Sandra Dysek; Karin Moser-Thier; Christine Pirker; Harald Höger; Inge M. Ambros; Peter F. Ambros; Walter Berger; Reginald E. Bittner
Carter GT, Abresch RT, Fowler WM Jr: Adaptations to exercise train- ing and contraction-induced muscle injury in animal models of muscular dystrophy. Am J Phys Med Rehabil 2002;81(Suppl):S151-S161. This article reviews the current status of exercise training and contrac- tion-induced muscle-injury investigations in animal models of muscular dystrophy. Most exercise-training studies have compared the adapta- tions of normal and dystrophic
Gregory T. Carter; R. Ted Abresch; William M. Fowler
BACKGROUND: There is little information on the morphometric characteristics of the diaphragm in patients with Duchenne muscular dystrophy. METHODS: The thickness of the diaphragm was measured at the zone of apposition using B mode ultrasonography in 10 boys with Duchenne muscular dystrophy of mean (SD) age 10.3 (1.3) years and 12 normal controls of mean (SD) age 11.3 (2.0) years
P. F. De Bruin; J. Ueki; A. Bush; Y. Khan; A. Watson; N. B. Pride
Deflazacort is the most commonly prescribed corticosteroid for the treatment of Duchenne muscular dystrophy in Canada. We review the long-term experience with deflazacort treatment at two centers in Canada; Montreal and Toronto. Deflazacort has benefitted both cohorts by prolonged ambulation, preserved cardiac and respiratory function, less scoliosis and improved survival. Common side effects in both cohorts include weight gain, decreased height and cataract formation. The Canadian experience supports the use of deflazacort in treating boys with Duchenne muscular dystrophy. PMID:22655512
McAdam, Laura C; Mayo, Amanda L; Alman, Benjamin A; Biggar, W Douglas
Ullrich congenital muscular dystrophy is a severe genetically and clinically heterogeneous muscle disorder linked to collagen VI deficiency. The pathogenesis of the disease is unknown. To assess the potential role of mitochondrial dysfunction in the onset of muscle fiber death in this form of dystrophy, we studied biopsies and myoblast cultures obtained from patients with different genetic defects of collagen
Alessia Angelin; Tania Tiepolo; Patrizia Sabatelli; Paolo Grumati; Natascha Bergamin; Cristina Golfieri; Elisabetta Mattioli; Francesca Gualandi; Alessandra Ferlini; Luciano Merlini; N. M. Maraldi; Paolo Bonaldo; Paolo Bernardi
Duchenne muscular dystrophy (DMD) is a disease linked to the X-chromosome which affects 1 in 3,600-6,000 newborn males. It is manifested by the absence of the dystrophin protein in muscle fibres, which causes progressive damage leading to death in the third decade of life. The only medication so far shown to be effective in delaying the progression of this illness are corticosteroids, which have been shown to increase muscle strength in randomised controlled studies; long-term studies have demonstrated that they prolong walking time and retard the progression of respiratory dysfunction, dilated cardiomyopathy and scoliosis. Several potential drugs are now being investigated. Genetic therapy, involving the insertion of a dystrophin gene through a vector, has proven effective in animals but not humans. Currently under clinical study is Ataluren, a molecule that binds with ribosomes and may allow the insertion of an aminoacid in the premature termination codon, and exon-skipping, which binds with RNA and excludes specific sites of RNA splicing, producing a dystrophin that is smaller but functional. There are also studies attempting to modulate other muscular proteins, such as myostatin and utrophin, to reduce symptoms. This paper does not address cardiomyopathy treatment in DMD patients. PMID:22655510
Beytía, Maria de los Angeles; Vry, Julia; Kirschner, Janbernd
Muscular dystrophies are a heterogeneous group of genetically inherited disorders whose most prominent clinical feature is progressive degeneration of skeletal muscle. In several forms of the disease, the function of cardiac muscle is likewise affected. The primary defect in this group of diseases is caused by mutations in myocyte proteins important to cellular structure and/or performance. That being stated, a growing body of evidence suggests that the development of autonomic dysfunction may secondarily contribute to the generation of skeletal and cardio-myopathy in muscular dystrophy. Indeed, abnormalities in the regulation of both sympathetic and parasympathetic nerve activity have been reported in a number of muscular dystrophy variants. However, the mechanisms mediating this autonomic dysfunction remain relatively unknown. An autonomic reflex originating in skeletal muscle, the exercise pressor reflex, is known to contribute significantly to the control of sympathetic and parasympathetic activity when stimulated. Given the skeletal myopathy that develops with muscular dystrophy, it is logical to suggest that the function of this reflex might also be abnormal with the pathogenesis of disease. As such, it may contribute to or exacerbate the autonomic dysfunction that manifests. This possibility along with a basic description of exercise pressor reflex function in health and disease are reviewed. A better understanding of the mechanisms that possibly underlie autonomic dysfunction in muscular dystrophy may not only facilitate further research but could also lead to the identification of new therapeutic targets for the treatment of muscular dystrophy.
Smith, Scott A.; Downey, Ryan M.; Williamson, Jon W.; Mizuno, Masaki
BACKGROUND--The effect on subsequent respiratory function of spinal stabilisation for scoliosis in Duchenne muscular dystrophy is unclear. In order to clarify this clinical problem, changes in the forced vital capacity of a group of children with Duchenne muscular dystrophy who had undergone spinal surgery were measured and compared with a group of children with Duchenne muscular dystrophy who had not had surgery. METHODS--In this retrospective study 17 boys with Duchenne muscular dystrophy who underwent spinal stabilisation at a mean age of 14.9 years (surgical group) were compared with 21 boys with Duchenne muscular dystrophy who had not had surgery (non-surgical group). The mean (SD) Cobb angle of the surgical group at 14.9 years was 57 (16.4) degrees, and of the non-surgical group at 15 years was 45 (29.9) degrees. Forced vital capacity expressed as percentage predicted (% FVC) was measured in total over a seven year period in the surgical group and over 6.5 years in the non-surgical group, and regression equations were calculated. Survival curves for both groups were also constructed. RESULTS--No difference was found between spinal stabilisation (surgical group) and the non-surgical group in the rate of deterioration of % FVC which was 3-5% per year. There was no difference in survival in either group. CONCLUSIONS--Spinal stabilisation in Duchenne muscular dystrophy does not alter the decline in pulmonary function, nor does it improve survival.
Kennedy, J. D.; Staples, A. J.; Brook, P. D.; Parsons, D. W.; Sutherland, A. D.; Martin, A. J.; Stern, L. M.; Foster, B. K.
Fukuyama-type congenital muscular dystrophy is an autosomal recessive disorder prevalent in Japan that is characterized by congenital muscular dystrophy, cobblestone lissencephaly, and eye anomalies. We examined 46 patients with Fukuyama-type congenital muscular dystrophy and followed their progress for more than 3 years, with special reference to long-term prognosis of seizure disorders and the relationship between seizures and neuropathologic abnormalities. Seizures
Mieko Yoshioka; Yoshihisa Higuchi
Fukuyama-type congenital muscular dystrophy is an autosomal recessive disorder prevalent in Japan that is characterized by congenital muscular dystrophy, cobblestone lissencephaly, and eye anomalies. We examined 46 patients with Fukuyama-type congenital muscular dystrophy and followed their progress for more than 3 years, with special reference to long-term prognosis of seizure disorders and the relationship between seizures and neuropathologic abnormalities. Seizures
Mieko Yoshioka; Yoshihisa Higuchi
Diagnosis of muscular dystrophies is currently based on invasive methods requiring muscle biopsies or blood tests. The aim of the present study was to identify urinary biomarkers as a diagnostic tool for muscular dystrophies. Here, the urinary proteomes of Duchenne muscular dystrophy (DMD) patients and healthy donors were compared with a bottom-up proteomic approach. Label-free analysis of more than 1100 identified proteins revealed that 32 of them were differentially expressed between healthy controls and DMD patients. Among these 32 proteins, titin showed the highest fold change between healthy subjects and DMD patients. Interestingly, most of the sequenced peptides belong to the N-terminal and C-terminal parts of titin, and the presence of the corresponding fragments in the urine of DMD patients was confirmed by Western blot analysis. Analysis of a large cohort of DMD patients and age-matched controls (a total of 104 individuals aged from 3 to 20years) confirmed presence of the N-ter fragment in all but two patients. In two DMD patients aged 16 and 20years this fragment was undetectable and two healthy controls of 16 and 19years with serum CK >800IU/L demonstrated a low level of the fragment. N- and C-terminal titin fragments were also detected in urine from patients with other muscular dystrophies such as Becker muscular dystrophy and Limb-girdle muscular dystrophy (type 1D, 2D and 2J) but not in neurogenic spinal muscular atrophy. They were also present in urine of dystrophin-deficient animal models (GRMD dogs and mdx mice). Titin is the first urinary biomarker that offers the possibility to develop a simple, non-invasive and easy-to-use test for pre-screening of muscular dystrophies, and may also prove to be useful for the non-invasive follow up of DMD patients under treatment. PMID:24813925
Rouillon, Jeremy; Zocevic, Aleksandar; Leger, Thibaut; Garcia, Camille; Camadro, Jean-Michel; Udd, Bjarne; Wong, Brenda; Servais, Laurent; Voit, Thomas; Svinartchouk, Fedor
The goal of the current investigation was to examine adaptive behavior and cognitive skills in young children with Duchenne muscular dystrophy (DMD), a genetic disorder that causes progressive muscular weakness and concomi- tant cognitive deficits. Previous studies have documented specific language deficits in older children with DMD, but there are limited data on younger children. Twenty children with DMD who
SHANA E. CYRULNIK; ROBERT J. FEE; ABIGAIL BATCHELDER; JACQUELINE KIEFEL; EDWARD GOLDSTEIN; VERONICA J. HINTON
Genetic defects in a number of components of the dystrophin–glycoprotein complex (DGC) lead to distinct forms of muscular dystrophy. However, little is known about how alterations in the DGC are manifested in the pathophysiology present in dystrophic muscle tissue. One hypothesis is that the DGC protects the sarcolemma from contraction-induced damage. Using tracer molecules, we compared sarcolemmal integrity in animal models for muscular dystrophy and in muscular dystrophy patient samples. Evans blue, a low molecular weight diazo dye, does not cross into skeletal muscle fibers in normal mice. In contrast, mdx mice, a dystrophin-deficient animal model for Duchenne muscular dystrophy, showed significant Evans blue accumulation in skeletal muscle fibers. We also studied Evans blue dispersion in transgenic mice bearing different dystrophin mutations, and we demonstrated that cytoskeletal and sarcolemmal attachment of dystrophin might be a necessary requirement to prevent serious fiber damage. The extent of dye incorporation in transgenic mice correlated with the phenotypic severity of similar dystrophin mutations in humans. We furthermore assessed Evans blue incorporation in skeletal muscle of the dystrophia muscularis (dy/dy) mouse and its milder allelic variant, the dy2J/dy2J mouse, animal models for congenital muscular dystrophy. Surprisingly, these mice, which have defects in the laminin ?2-chain, an extracellular ligand of the DGC, showed little Evans blue accumulation in their skeletal muscles. Taken together, these results suggest that the pathogenic mechanisms in congenital muscular dystrophy are different from those in Duchenne muscular dystrophy, although the primary defects originate in two components associated with the same protein complex.
Straub, Volker; Rafael, Jill A.; Chamberlain, Jeffrey S.; Campbell, Kevin P.
Background This study was designed to assess whether cardiovascular magnetic resonance imaging (CMR) in Duchenne muscular dystrophy carriers (DMDc) may index any cell milieu elements of LV dysfunction and whether this cardiac phenotype may be related to genotype. The null hypothesis was that myocardial fibrosis, assessed by late gadolinium enhancement (LGE), might be similarly accounted for in DMDc and gender and age-matched controls. Methods Thirty DMDc patients had CMR and genotyping with 37 gender and age-matched controls. Systolic and diastolic LV function was assessed by 2D-echocardiography. Results Absolute and percent LGE were higher in muscular symptomatic (sym) than asymptomatic (asy) DMDc (1.77?±?0.27 vs 0.76?±?0.17 ml; F =?19.6, p 0.0001 and 1.86?±?0.26% vs 0.68?±?0.17%, F =?22.1, p 0.0001, respectively). There was no correlation between LGE and age. LGE was seen most frequently in segments 5 and 6; segment 5 was involved in all asy-DMDc. Subepicardial LGE predominated, compared to the mid-myocardial one (11 out of 14 DMDc). LGE was absent in the subendocardium. No correlations were seen between genotyping (type of mutation, gene region and protein domain), confined to the exon’s study, and cardiac phenotype. Conclusions A typical myocardial LGE-pattern location (LV segments 5 and 6) was a common finding in DMDc. LGE was more frequently subepicardial plus midmyocardial in sym-DMDc, with normal LV systolic and diastolic function. No genotype-phenothype correlation was found.
To investigate the natural course of the spinal deformity in Duchenne muscular dystrophy (DMD) and its clinical relevance, longitudinal series of spinal radiographs and medical records of 46 patients with DMD were reviewed. The natural course of the deformity was classified into three types; type 1 (n = 21), unremittent progression of scoliosis with kyphosis; type 2 (n = 18), transition from kyphosis to lordosis before age 15 years; and type 3 (n = 7), less deformity without prominent longitudinal changes. Age at loss of ambulatory ability was not a predictor of type. Neither was the age at which the Cobb angle was 30 degrees correlated with the rate of subsequent progression. Because the spinal deformity always progresses, we consider spinal surgery justifiable in type 1, when a certain strict indication exists, such as spinal deformity > 30 degrees and age < 15 years in patients with > 35% predicted value of vital capacity. In type 2, operation may be necessary in patients in whom Cobb angle will progress unremittently. There is no surgical indication for patients with type 3. PMID:8370781
Oda, T; Shimizu, N; Yonenobu, K; Ono, K; Nabeshima, T; Kyoh, S
Duchenne and Becker muscular dystrophy (DMD/BMD) comprise a spectrum of devastating X-linked muscle wasting disease for which there is no treatment. DMD/BMD is caused by mutations in the gene encoding dystrophin, a cytoskeletal protein that stabilizes the muscle membrane and also targets other proteins to the sarcolemma. Among these is the muscle-specific isoform of neuronal nitric oxide synthase (nNOS?) which binds spectrin-like repeats within dystrophin's rod domain and the adaptor protein ?-syntrophin. Dystrophin deficiency causes loss of sarcolemmal nNOS? and reduces paracrine signaling of muscle-derived nitric oxide (NO) to the microvasculature, which renders the diseased muscle fibers susceptible to functional muscle ischemia during exercise. Repeated bouts of functional ischemia superimposed on muscle fibers already weakened by dystrophin deficiency result in use-dependent focal muscle injury. Genetic and pharmacologic strategies to boost nNOS?-NO signaling in dystrophic muscle alleviate functional muscle ischemia and show promise as novel therapeutic interventions for the treatment of DMD/BMD.
Thomas, Gail D.
Duchenne and Becker muscular dystrophy (DMD/BMD) comprise a spectrum of devastating X-linked muscle wasting disease for which there is no treatment. DMD/BMD is caused by mutations in the gene encoding dystrophin, a cytoskeletal protein that stabilizes the muscle membrane and also targets other proteins to the sarcolemma. Among these is the muscle-specific isoform of neuronal nitric oxide synthase (nNOS?) which binds spectrin-like repeats within dystrophin's rod domain and the adaptor protein ?-syntrophin. Dystrophin deficiency causes loss of sarcolemmal nNOS? and reduces paracrine signaling of muscle-derived nitric oxide (NO) to the microvasculature, which renders the diseased muscle fibers susceptible to functional muscle ischemia during exercise. Repeated bouts of functional ischemia superimposed on muscle fibers already weakened by dystrophin deficiency result in use-dependent focal muscle injury. Genetic and pharmacologic strategies to boost nNOS?-NO signaling in dystrophic muscle alleviate functional muscle ischemia and show promise as novel therapeutic interventions for the treatment of DMD/BMD. PMID:24391598
Thomas, Gail D
Objectives: Duchenne muscular dystrophy (DMD) is a degenerative muscle wasting disease caused by mutations in the dystrophin gene. Dystrophic muscle is characterized by chronic inflammation, and inflammatory mediators could be promising targets for innovative therapeutic interventions. We analyzed muscle biopsy samples of DMD-affected children to characterize interleukin (IL)-17 and Forkhead box P3 (Foxp3) expression levels and to identify possible correlations with clinical status. Methods: Expression levels of IL-17, Foxp3, tumor necrosis factor-? (TNF-?), monocyte chemoattractant protein-1 (MCP-1), IL-6, and transforming growth factor-? (TGF-?) were analyzed by real-time PCR in muscle biopsy samples from patients with DMD (n = 27) and juvenile dermatomyositis (JDM) (n = 8). Motor outcome of patients with DMD was evaluated by North Star Ambulatory Assessment score. Results: In DMD, we found higher levels of IL-17 and lower levels of Foxp3 mRNA compared with those for a typical inflammatory myopathy, JDM. Moreover, the IL-17/Foxp3 ratio was higher in DMD than in JDM biopsy samples. IL-17 mRNA levels appeared to be related to the expression levels of other proinflammatory cytokines (TNF-? and MCP-1) and significantly associated with clinical outcome of patients. Conclusions: The association of IL-17 expression with levels of other inflammatory cytokines and with the clinical course of DMD suggests a possible pathogenic role of IL-17.
De Pasquale, L.; D'Amico, A.; Verardo, M.; Petrini, S.; Bertini, E.
Prognosis in patients with Duchenne muscular dystrophy (DMD) is guarded, and most deaths are due to cardiac or respiratory causes. It is unclear if some DMD gene mutations might be predictive of either mild or severe cardiac dysfunction. We studied 75 patients with DMD followed at our institution. Cardiac function, as assessed by yearly echocardiography, showed marked variability in left ventricular (LV) function. Some patients in their 3rd decade had no or minimal dysfunction, whereas others in their 2nd decade had very severe dysfunction. Therefore, 4 severity groups were defined ranging from no or mild LV dysfunction to severe LV dysfunction using patient age at first abnormal echocardiographic finding and degree of LV dysfunction. Genetic data were collected for all patients. Most patients had mutations from exon 1 to 20 to exon 41 to 55. The distribution of the 4 severity groups of LV dysfunction did not significantly differ between these 2 mutation groups. An analysis based on the number of exons involved (<5 vs ?5 exons) also found no significant difference in cardiac severity. When patients having identical mutations were compared with their cardiac course, concordance was often not evident. Steroid therapy had no apparent protection for the development of cardiomyopathy. In conclusion, 75 patients with DMD showed marked variability in the severity of LV dysfunction. Neither the age of onset nor the severity of cardiomyopathy correlated with any of the mutation groups. PMID:24878125
Ashwath, Mahi L; Jacobs, Irwin B; Crowe, Carol A; Ashwath, Ravi C; Super, Dennis M; Bahler, Robert C
Duchenne muscular dystrophy (DMD) is a common lethal sex-linked recessive disorder. Seventy percent of the cases are inherited and 30% are due to mutations. The mainstay of prevention is detection of female carriers and antenatal diagnosis of affected foetuses. Before the era of molecular diagnosis, DMD has been clinically defined. Serum creatine kinase (CK) has also been used to screen women at risk for carrier status. With the isolation and sequencing of the DMD gene at Xp21 and the identification of the DMD gene-product dystrophin, DNA technology can be applied for the diagnosis of the affected, for the detection of carriers and in antenatal diagnosis. The multiplex polymerase chain reaction (PCR) technique offers a rapid and simple screening method for deletions of the gene. We were able to detect partial deletions which account for 58.3% of gene defects in our patients. This direct demonstration of the gene defect that causes DMD gives a 100% assurance of accuracy and specificity of the diagnosis. Linkage analysis is especially useful for prenatal diagnosis and carrier detection in the remaining 41.7% of families without detectable deletions or duplications. This approach however is indirect and is dependent on information on genotypes from affected males and key family members. With the availability of increasingly more restriction fragment length polymorphisms (RFLPs), it has become practical to use the haplotype method for accurate carrier detection and prenatal diagnosis. PMID:8779553
Low, P S; Lai, P S; Lee, W L; Chin, S M; Ong, H T; Tay, J S
Dystrophin absence in Duchenne muscular dystrophy (DMD) causes severe muscle degeneration. We describe that, as consequence of fibre damage, specific muscle-miRNAs are released in to the bloodstream of DMD patients and their levels correlate with the severity of the disease. The same miRNAs are abundant also in the blood of mdx mice and recover to wild-type levels in animals ‘cured’ through exon skipping. Even though creatine kinase (CK) blood levels have been utilized as diagnostic markers of several neuromuscular diseases, including DMD, we demonstrate that they correlate less well with the disease severity. Although the analysis of a larger number of patients should allow to obtain more refined correlations with the different stages of disease progression, we propose that miR-1, miR-133, and miR-206 are new and valuable biomarkers for the diagnosis of DMD and possibly also for monitoring the outcomes of therapeutic interventions in humans. Despite many different DMD therapeutic approaches are now entering clinical trials, a unifying method for assessing the benefit of different treatments is still lacking.
Cacchiarelli, Davide; Legnini, Ivano; Martone, Julie; Cazzella, Valentina; D'Amico, Adele; Bertini, Enrico; Bozzoni, Irene
Becker's Muscular Dystrophy (BMD) is a dystrophinopathy manifested as progressive muscle degeneration. Autologous Bone Marrow Mononuclear Cells (BMMNCs) have shown some myogenic potential. The paracrine effects of the BMMNCs reduce the inflammation and are thought to reduce muscle degeneration. We treated a 39 year old dental surgeon suffering from BMD. Muscle strength was reduced when measured using modified Medical Research Council's Manual Muscle Testing (mMRC-MMT). Static sitting balance was poor. He was wheelchair dependent for ambulation and moderately independent in Activities of Daily Living (ADL). Functional Independence Measure (FIM) score was 93. Musculoskeletal Magnetic Resonance Imaging (MRI-MSK) showed moderate fatty infiltration in the muscles. Three cellular transplantations were carried out. Clinical assessment and the investigations were repeated. Progressive increase in the muscle strength was noted. Ambulation was independent using push-knee splints and minimal assistance when weary. Static and dynamic balance in sitting and standing improved. FIM score increased from 93 to 105. There was no increase in the degree of fatty infiltration, as seen on the MRI-MSK. The case study provides evidence for the putative benefits of cellular therapy in altering the disease progression in BMD. It also suggests augmented clinical benefits of combination of cellular therapy and rehabilitation.
Sharma, Alok; Sane, Hemangi; Bhagawanani, Khushboo; Gokulchandran, Nandini; Badhe, Prerna
Facioscapulohumeral muscular dystrophy (FSHD) is a progressive neuromuscular disorder caused by contractions of repetitive elements within the macrosatellite D4Z4 on chromosome 4q35. The pathophysiology of FSHD is unknown and, as a result, there is currently no effective treatment available for this disease. To better understand the pathophysiology of FSHD and develop mRNA-based biomarkers of affected muscles, we compared global analysis of gene expression in two distinct muscles obtained from a large number of FSHD subjects and their unaffected first-degree relatives. Gene expression in two muscle types was analyzed using GeneChip Gene 1.0 ST arrays: biceps, which typically shows an early and severe disease involvement; and deltoid, which is relatively uninvolved. For both muscle types, the expression differences were mild: using relaxed cutoffs for differential expression (fold change ?1.2; nominal P value <0.01), we identified 191 and 110 genes differentially expressed between affected and control samples of biceps and deltoid muscle tissues, respectively, with 29 genes in common. Controlling for a false-discovery rate of <0.25 reduced the number of differentially expressed genes in biceps to 188 and in deltoid to 7. Expression levels of 15 genes altered in this study were used as a "molecular signature" in a validation study of an additional 26 subjects and predicted them as FSHD or control with 90% accuracy based on biceps and 80% accuracy based on deltoids. PMID:22988124
Rahimov, Fedik; King, Oliver D; Leung, Doris G; Bibat, Genila M; Emerson, Charles P; Kunkel, Louis M; Wagner, Kathryn R
Facioscapulohumeral muscular dystrophy (FSHD) is a neuromuscular disease, characterized by an autosomal dominant mode of inheritance, facial involvement, and selectivity and asymmetry of muscle involvement. In general, FSHD typically presents before age 20 years. Usually, FSHD muscle involvement starts in the face and then progresses to the shoulder girdle, the humeral muscles and the abdominal muscles, and then the anterolateral compartment of the leg. Disease severity is highly variable and progression is very slow. About 20% of FSHD patients become wheelchair-bound. Lifespan is not shortened. The diagnosis of FSHD is based on a genetic test by which a deletion of 3.3kb DNA repeats (named D4Z4 and mapping to the subtelomeric region of chromosome 4q35) is identified. The progressive pattern of FSHD requires that the severity of symptoms as well as their physical, social and psychological impact be evaluated on a regular basis. A yearly assessment is recommended. Multidisciplinary management of FSHD--consisting of a combination of genetic counselling, functional assessment, an assessment by a physical therapist, prescription of symptomatic therapies and prevention of known complications of this disease--is required. Prescription of physical therapy sessions and orthopedic appliances are to be adapted to the patient's deficiencies and contractures. PMID:22551571
Attarian, S; Salort-Campana, E; Nguyen, K; Behin, A; Andoni Urtizberea, J
Recent advances in the understanding of the molecular pathophysiology of facioscapulohumeral muscular dystrophy (FSHD) have identified potential therapeutic targets. Consequently, an accurate understanding of disease progression in FSHD is crucial for the design of future clinical trials. Data from 228 subjects in 3 clinical trials and 1 natural history study were compared to examine disease progression in FSHD. All studies utilized the same techniques for manual muscle testing and maximum voluntary isometric contraction testing. Both techniques yield a total strength score that can be followed over time as an indicator of disease progression. Whereas natural history data showed a decrease in strength over 1 year, there was an apparent increase in strength at 6 months in 2 of the 3 clinical trials in both the placebo and treatment groups, that persisted for up to 1 year for maximum voluntary isometric contraction testing. Variability estimates from the clinical trial data were consistent with those seen in the natural history data. Patients in clinical trials in FSHD may have better outcomes than those in natural history studies, regardless of treatment assignment, emphasizing the importance of placebo groups and the need for caution when interpreting the strength results of controlled and uncontrolled trials. PMID:23406877
Statland, Jeffrey M; McDermott, Michael P; Heatwole, Chad; Martens, William B; Pandya, Shree; van der Kooi, E L; Kissel, John T; Wagner, Kathryn R; Tawil, Rabi
Thirty four symptomatic and 17 presymptomatic (PS) patients from 21 autosomal dominant facioscapuloperoneal muscular dystrophy (FSPMD) families were found by the probe p13E-11 and enzymes EcoRI/BlnI to have DNA fragments size (DFS) between 13-35 kb (double digestion) and in other 8 PS patients - 37-39 kb, in one PS woman - 45 kb caused by deletion related to the disease and linked with chromosome 4q35. In all the families which had the same or different DFS ranging between 13-35 kb we observed similar clinical variability of phenotypes (the static muscle pattern), the severity of the disease (SD) and daily-life work disability (LD) in the families and between the families. We found no significant correlation between DFS and the phenotype, DFS and the age at onset of the disease, DFS and SD, DFS and LD. Thus, it is confirmed that the probe p13E-11 can be used for detecting DFS between 13-35 kb (or 37 kb) (double digestion) for FSPMD which are assigned with chromosome 4q35. However, in patients with typical FSHD the 4q35-linked EcoRI fragment detected by p13E-11 is usually shorter than 38 kb. Therefore, we believe that the detected DFS cannot be the criterion for establishing genetic heterogeneity of FSHD. It is possible that FSPD and FSHD are allelic diseases. PMID:19537084
Rudenko, D I; Kazakov, B M; Skoromets, A A; Magomedova, N K
Recently we reported a cytoplasmic sodium overload to cause a severe osmotic oedema in Duchenne muscular dystrophy (DMD). Our results suggested that this dual overload of sodium ions and water precedes the dystrophic process and persists until fatty muscle degeneration is complete. The present paper addresses the questions as to whether these overloads are important for the pathogenesis of the disease, and if so, whether they can be treated. As a first step, we investigated the effects of various diuretic drugs on a cell model of DMD, i.e. rat diaphragm strips previously exposed to amphotericin B. We found that both carbonic anhydrase inhibitors and aldosterone antagonists were able to repolarise depolarised muscle fibres. Since carbonic anhydrase inhibitors are known to have acidifying effects and this might be detrimental to the ventilation of DMD patients, we mainly concentrated on the modern spironolactone derivative, eplerenone. This drug had a very high repolarizing power, the parameter considered by us as being most relevant for a beneficial effect. In a pilot study we administered this drug to a 22-yr-old female DMD patient who was bound to an electric wheelchair and has had no corticosteroid therapy before. Eplerenone decreased both cytoplasmic sodium and water overload and increased muscle strength and mobility. We conclude that eplerenone has beneficial effects on DMD muscle. In our opinion the cytoplasmic oedema is cytotoxic and should be treated before fatty degeneration takes place. PMID:22655515
Lehmann-Horn, Frank; Weber, Marc-André; Nagel, Armin M; Meinck, Hans-Michael; Breitenbach, Simon; Scharrer, Johannes; Jurkat-Rott, Karin
Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder caused by mutations in the DMD gene, affecting 1 in 3500 newborn males. Complete loss of muscle dystrophin protein causes progressive muscle weakness and heart and respiratory failure, leading to premature death. Antisense oligonucleotides (AONs) that bind to complementary sequences of the dystrophin pre-mRNA to induce skipping of the targeted exon by modulating pre-mRNA splicing are promising therapeutic agents for DMD. Such AONs can restore the open reading frame of the DMD gene and produce internally deleted, yet partially functional dystrophin protein isoforms in skeletal muscle. Within the last few years, clinical trials using AONs have made considerable progress demonstrating the restoration of functional dystrophin protein and acceptable safety profiles following both local and systemic delivery in DMD patients. However, improvement of AON delivery and efficacy, along with the development of multiple AONs to treat as many DMD patients as possible needs to be addressed for this approach to fulfill its potential. Here, we review the recent progress made in clinical trials using AONs to treat DMD and discuss the current challenges to the development of AON-based therapy for DMD. PMID:23521559
Koo, Taeyoung; Wood, Matthew J
A 23-year-old male with Duchenne muscular dystrophy (DMD) experienced self-limiting palpitations at age 19 years for the first time. Palpitations recurred not earlier than at age 23 years, and were attributed to narrow complex tachycardia, which could be terminated with adenosine. Since electrocardiography showed a delta-wave, Wolff-Parkinson-White (WPW) syndrome was diagnosed, ajmaline prescribed and radio-frequency catheter ablation of three accessory pathways carried out one week later. One day after ablation, however, a relapse of the supraventricular tachycardia occurred and was terminated with ajmaline. Re-entry tachycardia occurred a second time six days after ablation, and as before, it was stopped only with ajmaline. Despite administration of verapamil to prevent tachycardia, it occurred a third time four months after ablation. This case shows that cardiac involvement in DMD may manifest also as WPW-syndrome. In these patients, repeated radio-frequency catheter ablation of accessory pathways may be necessary to completely block the re-entry mechanism.
Stollberger, Claudia; Steger, Christine; Gatterer, Edmund
Twenty known cases of X;autosome translocations with breakpoints at Xp21 associated with Duchenne or Becker muscular dystrophy in girls are reviewed. The variable severity described for different persons may reflect differences in X inactivation or in the nature of the genomic target disrupted. High resolution cytogenetic studies on 12 cases indicate breakpoints on the X chromosome at Xp21.1 or Xp21.2. Translocation chromosomes from several of these cases have been isolated in human/mouse somatic cell hybrids. Molecular heterogeneity in the breakpoint positions has been established by probing DNA from these hybrids with a range of cloned sequences known to be located within, or closely linked to, the Duchenne region. The minimum separation between the most distal and the most proximal breakpoints is 176 kb suggesting that, if a single gene is involved, it must be large. Alternatively, the translocations may affect different genes, or confer alterations to regulatory sequences which operate at a distance. PMID:3806636
Boyd, Y; Buckle, V; Holt, S; Munro, E; Hunter, D; Craig, I
Patients with Duchenne muscular dystrophy (DMD) report masticatory and swallowing problems. Such problems may cause complications such as choking, and feeling of food sticking in the throat. We investigated whether masticatory performance in DMD is objectively impaired, and explored predictive factors for compromised mastication. Twenty-three patients and 23 controls filled out two questionnaires about mandibular function, and underwent a clinical examination of the masticatory system and measurements of anterior bite force and masticatory performance. In the patients, moreover, quantitative ultrasound of the tongue and motor function measurement was performed. The patients were categorized into ambulatory stage (early or late), early non-ambulatory stage, or late non-ambulatory stage. Masticatory performance, anterior bite force and occlusal contacts were all reduced in the patient group compared to the controls (all p<0.001). Mastication abnormalities were present early in the disease process prior to a reduction of motor function measurement. The early non-ambulatory and late non-ambulatory stage groups showed less masticatory performance compared to the ambulatory stage group (p<0.028 and p<0.010, respectively). Multiple linear regression analysis revealed that stage of the disease was the strongest independent risk factor for the masticatory performance (R(2)=0.52). Anterior bite force, occlusal contacts and masticatory performance in DMD are severely reduced. PMID:24969130
van Bruggen, H W; van de Engel-Hoek, L; Steenks, M H; Bronkhorst, E M; Creugers, N H J; de Groot, I J M; Kalaykova, S I
Objective: To investigate whether sarcomeric dysfunction contributes to muscle weakness in facioscapulohumeral muscular dystrophy (FSHD). Methods: Sarcomeric function was evaluated by contractile studies on demembranated single muscle fibers obtained from quadriceps muscle biopsies of 4 patients with FSHD and 4 healthy controls. The sarcomere length dependency of force was determined together with measurements of thin filament length using immunofluorescence confocal scanning laser microscopy. X-ray diffraction techniques were used to study myofilament lattice spacing. Results: FSHD muscle fibers produced only 70% of active force compared to healthy controls, a reduction which was exclusive to type II muscle fibers. Changes in force were not due to changes in thin filament length or sarcomere length. Passive force was increased 5- to 12-fold in both fiber types, with increased calcium sensitivity of force generation and decreased myofilament lattice spacing, indicating compensation by the sarcomeric protein titin. Conclusions: We have demonstrated a reduction in sarcomeric force in type II FSHD muscle fibers, and suggest compensatory mechanisms through titin stiffening. Based on these findings, we propose that sarcomeric dysfunction plays a critical role in the development of muscle weakness in FSHD.
Stienen, Ger J.M.; Irving, Tom C.; van der Maarel, Silvere M.; Voermans, Nicol C.; Padberg, George W.; Granzier, Henk; van Engelen, Baziel G.M.; Ottenheijm, Coen A.C.
Limb girdle muscular dystrophy type 2 G (LGMD2G) is caused by mutations in the telethonin gene. Only few families were described presenting this disease, and they are mainly Brazilians. Here, we identified one additional case carrying the same common c.157C > T mutation in the telethonin gene but with an atypical histopathological muscle pattern. In a female patient with a long duration of symptoms (46 years), muscle biopsy showed, in addition to telethonin deficiency, the presence of nemaline rods, type 1 fiber predominance, nuclear internalization, lobulated fibers, and mitochondrial paracrystalline inclusions. Her first clinical signs were identified at 8 years old, which include tiptoe walking, left lower limb deformity, and frequent falls. Ambulation loss occurred at 41 years old, and now, at 54 years old, she presented pelvic girdle atrophy, winging scapula, foot deformity with incapacity to perform ankle dorsiflexion, and absent tendon reflexes. The presence of nemaline bodies could be a secondary phenomenon, possibly associated with focal Z-line abnormalities of a long-standing disease. However, these new histopathological findings, characteristic of congenital myopathies, expand muscle phenotypic variability of telethoninopathy. PMID:23479141
Paim, Julia F; Cotta, Ana; Vargas, Antonio P; Navarro, Monica M; Valicek, Jaquelin; Carvalho, Elmano; da-Cunha, Antonio L; Plentz, Estevão; Braz, Shelida V; Takata, Reinaldo I; Almeida, Camila F; Vainzof, Mariz
Conventional EMG, motor and sensory conduction velocities, averaging analysis of MUPs, SFEMG, and muscle fiber conduction velocity in situ were performed in 14 boys with Duchenne muscular dystrophy (DD) aged 5 to 11 years. MUPs parameters study showed a striking increment of long duration MUPs followed by satellites and increase of polyphasic potentials of variable duration. The main findings in SFEMG examination were increment in fiber density of the motor unit, large MISI and presence of complex potentials of long duration in all patients. Muscle fiber conduction velocity in situ was significantly slower than in controls, with significant decrease in minimum conduction and increased variability (large SD) in propagation velocity values. Low conduction velocity of muscle fibers, long duration of polyphasics and MUPs followed by satellites, and large MISI were significantly related. These findings support the hypotheses which have suggested that the motor unit remodelling in DD is mainly myogenic. The abnormalities in muscle fiber conduction velocity in situ reflect an increased diameter variation of muscle fibers consistent with splitting fibers, small groups of regenerating and necrotic fibers, and fiber diameter variation found in histological studies. Thus, increased variability in fiber diameter may be the cause of complex and long duration MUPs in DD. PMID:1526215
Cruz Martínez, A; López-Terradas, J M
Golden retriever and Labrador retriever muscular dystrophy are inherited progressive degenerative myopathies that are used as models of Duchenne muscular dystrophy in man. Thoracic lesions were reported to be the most consistent radiographic finding in golden retriever dogs in a study where radiographs were performed at a single-time point. Muscular dystrophy worsens clinically over time and longitudinal studies in dogs are lacking. Thus our goal was to describe the thoracic abnormalities of golden retriever and Labrador retriever dogs, to determine the timing of first expression and their evolution with time. To this purpose, we retrospectively reviewed 390 monthly radiographic studies of 38 golden retrievers and six Labrador retrievers with muscular dystrophy. The same thoracic lesions were found in both golden and Labrador retrievers. They included, in decreasing frequency, flattened and/or scalloped diaphragmatic shape (43/44), pulmonary hyperinflation (34/44), hiatal hernia (34/44), cranial pectus excavatum (23/44), bronchopneumonia (22/44), and megaesophagus (14/44). The last three lesions were not reported in a previous radiographic study in golden retriever dogs. In all but two dogs the thoracic changes were detected between 4 and 10 months and were persistent or worsened over time. Clinically, muscular dystrophy should be included in the differential diagnosis of dogs with a combination of these thoracic radiographic findings. PMID:22702494
Bedu, Anne-Sophie; Labruyère, Julien J; Thibaud, Jean Laurent; Barthélémy, Inès; Leperlier, Dimitri; Saunders, Jimmy H; Blot, Stéphane
Muscular dystrophies comprise a diverse group of genetic disorders that lead to muscle wasting and, in many instances, premature death1. Many mutations that cause muscular dystrophy compromise the support network that connects myofilament proteins within the cell to the basal lamina outside the cell, rendering the sarcolemma more permeable or leaky. Here we show that deletion of the gene encoding cyclophilin D (Ppif) rendered mitochondria largely insensitive to the calcium overload–induced swelling associated with a defective sarcolemma, thus reducing myofiber necrosis in two distinct models of muscular dystrophy. Mice lacking ?-sarcoglycan (Scgd?/? mice) showed markedly less dystrophic disease in both skeletal muscle and heart in the absence of Ppif. Moreover, the premature lethality associated with deletion of Lama2, encoding the ?-2 chain of laminin-2, was rescued, as were other indices of dystrophic disease. Treatment with the cyclophilin inhibitor Debio-025 similarly reduced mitochondrial swelling and necrotic disease manifestations in mdx mice, a model of Duchenne muscular dystrophy, and in Scgd?/? mice. Thus, mitochondrial-dependent necrosis represents a prominent disease mechanism in muscular dystrophy, suggesting that inhibition of cyclophilin D could provide a new pharmacologic treatment strategy for these diseases.
Millay, Douglas P; Sargent, Michelle A; Osinska, Hanna; Baines, Christopher P; Barton, Elisabeth R; Vuagniaux, Gregoire; Sweeney, H Lee; Robbins, Jeffrey; Molkentin, Jeffery D
Most single-gene diseases, including muscular dystrophy, display a nonuniform phenotype. Phenotypic variability arises, in part, due to the presence of genetic modifiers that enhance or suppress the disease process. We employed an unbiased mapping approach to search for genes that modify muscular dystrophy in mice. In a genome-wide scan, we identified a single strong locus on chromosome 7 that influenced two pathological features of muscular dystrophy, muscle membrane permeability and muscle fibrosis. Within this genomic interval, an insertion/deletion polymorphism of 36 bp in the coding region of the latent TGF-?–binding protein 4 gene (Ltbp4) was found. Ltbp4 encodes a latent TGF-?–binding protein that sequesters TGF-? and regulates its availability for binding to the TGF-? receptor. Insertion of 12 amino acids into the proline-rich region of LTBP4 reduced proteolytic cleavage and was associated with reduced TGF-? signaling, decreased fibrosis, and improved muscle pathology in a mouse model of muscular dystrophy. In contrast, a 12-amino-acid deletion in LTBP4 was associated with increased proteolysis, SMAD signaling, and fibrosis. These data identify Ltbp4 as a target gene to regulate TGF-? signaling and modify outcomes in muscular dystrophy.
Heydemann, Ahlke; Ceco, Ermelinda; Lim, Jackie E.; Hadhazy, Michele; Ryder, Pearl; Moran, Jennifer L.; Beier, David R.; Palmer, Abraham A.; McNally, Elizabeth M.
The muscular dystrophies are a broad group of hereditary muscle diseases with variable severity. Population-based prevalence estimates have been reported but pooled estimates are not available. We performed a systematic review of worldwide population-based studies reporting muscular dystrophies prevalence and/or incidence using MEDLINE and EMBASE databases. The search strategy included key terms related to muscular dystrophies, incidence, prevalence and epidemiology. Two reviewers independently reviewed all abstracts, full text articles and abstracted data using standardized forms. Pooling of prevalence estimates was performed using random effect models. 1104 abstracts and 167 full text articles were reviewed. Thirty-one studies met all eligibility criteria and were included in the final analysis. The studies differed widely in their approaches to case ascertainment, resulting in significant methodological heterogeneity and varied data quality. The pooled prevalence of DMD and BMD was 4.78 (95% CI 1.94-11.81) and 1.53 (95% CI 0.26-8.94) per 100,000 males respectively. The incidence of DMD ranged from 10.71 to 27.78 per 100,000. This is the first meta-analysis of worldwide prevalence estimates for muscular dystrophies. There is a need for more epidemiological studies addressing global estimates on incidence and prevalence of muscular dystrophies, utilizing standardized diagnostic criteria as well as multiple sources of case ascertainment. PMID:24780148
Mah, Jean K; Korngut, Lawrence; Dykeman, Jonathan; Day, Lundy; Pringsheim, Tamara; Jette, Nathalie
ABSTRACT We describe a case of human Becker muscular dystrophy (BMD)-like myopathy that was characterized by the declined stainability of dystrophin at sarcolemma in a pig and the immunostaining for dystrophin on the formalin-fixed, paraffin-embedded (FFPE) tissue. The present case was found in a meat inspection center. The pig looked appeared healthy at the ante-mortem inspection. Muscular abnormalities were detected after carcass dressing as pale, discolored skeletal muscles with prominent fat infiltrations and considered so-called “fatty muscular dystrophy”. Microscopic examination revealed following characteristics: diffused fat infiltration into the skeletal muscle and degeneration and regeneration of the remaining skeletal muscle fibers. Any lesions that were suspected of neurogenic atrophy, traumatic muscular degeneration, glycogen storage disease or other porcine muscular disorders were not observed. The immunostaining for dystrophin was conducted and confirmed to be applicable on FFPE porcine muscular tissues and revealed diminished stainability of dystrophin at the sarcolemma in the present case. Based on the histological observations and immunostaining results, the present case was diagnosed with BMD-like myopathy associated with dystrophin abnormality in a pig. Although the genetic properties were not clear, the present BMD-like myopathy implied the occurrence of dystrophinopathy in pigs. To the best of our knowledge, this is the first report of a natural case of myopathy associated with dystrophin abnormalities in a pig.
HORIUCHI, Noriyuki; AIHARA, Naoyuki; MIZUTANI, Hiroshi; KOUSAKA, Shinichi; NAGAFUCHI, Tsuneyuki; OCHIAI, Mariko; OCHIAI, Kazuhiko; KOBAYASHI, Yoshiyasu; FURUOKA, Hidefumi; ASAI, Tetsuo; OISHI, Koji
The Duchenne and Becker forms of muscular dystrophy are associated with dilated cardiomyopathy and are diseases in which pulmonary function peaks, then progressively declines. In this report, we quantify cardiopulmonary function variability among brothers. Brothers in 3 of 7 eligible sibships had discordant pulmonary function, with significant differences between the brothers' peak forced vital capacities and their vital capacities at last comparable age. There was no relationship between pulmonary and cardiac function among the siblings. We concluded that despite identical genetic mutations, cardiac and pulmonary function variability was common among brothers in our clinic with Duchenne or Becker muscular dystrophy. If confirmed by larger studies, these results have negative implications for use of genetic testing to predict cardiopulmonary course and response to therapies in Duchenne or Becker muscular dystrophy.
Birnkrant, David J.; Ashwath, Mahi Lakshmi; Noritz, Garey H.; Merrill, Michelle C.; Shah, Tushar A.; Crowe, Carol A.; Bahler, Robert C.
Background. Duchenne muscular dystrophy (DMD) patients used to die mainly from pulmonary problems. However, as advances in respiratory care increase life expectancy, mortality due to cardiomyopathy rises. Echocardiography remains the standard diagnostic modality for cardiomyopathy in DMD patients, but is hampered by scoliosis and poor echocardiographic acoustic windows in adult DMD patients. Multigated cardiac radionuclide ventriculography (MUGA) does not suffer from these limitations. N-terminal proBNP (NTproBNP) has shown to be a diagnostic factor for heart failure. We present our initial experience with plasma NT-proBNP measurement in the routine screening and diagnosis of cardiomyopathy in adult mechanically ventilated DMD patients. Methods. Retrospective study, 13 patients. Echocardiography classified left ventricular (LV) function as preserved or depressed. NT-proBNP was determined using immunoassay. LV ejection fraction (LVEF) was determined using MUGA. Results. Median (range) NT-proBNP was 73 (25 to 463) ng/l. Six patients had an NT-proBNP >125 ng/l. Seven patients showed an LVEF <45% on MUGA. DMD patients with depressed LV function (n=4) as assessed by echocardiography had significantly higher median NT-proBNP than those (n=9) with preserved LV function: 346 (266 to 463) ng/l versus 69 (25 to 257) ng/l (p=0.003). NT-proBNP significantly correlated with depressed LV function on echocardiogram and with LVEF determined by MUGA. Conclusion. Although image quality of MUGA is superior to echocardiography, the combination of echocardiography and NT-proBNP achieves similar results in the evaluation of left ventricular function and is less time consuming and burdensome for our patients. We advise to add NT-proBNP to echocardiography in the routine cardiac assessment of DMD patients. (Neth Heart J 2009;17:232-7.19789685) PMID:19789685
van Bockel, E.A.P.; Lind, J.S.; Zijlstra, J.G.; Wijkstra, P.J.; Meijer, P.M.; van den Berg, M.P.; Slart, R.H.J.A.; Aarts, L.P.H.J.; Tulleken, J.E.
Objective: There are currently no effective treatments to halt the muscle breakdown in Duchenne muscular dystrophy (DMD), although genetic-based clinical trials are being piloted. Most of these trials have as an endpoint the restoration of dystrophin in muscle fibers, hence requiring sufficiently well-preserved muscle of recruited patients. The choice of the muscles to be studied and the role of noninvasive methods to assess muscle preservation therefore require further evaluation. Methods: We studied the degree of muscle involvement in the lower leg muscles of 34 patients with DMD >8 years, using muscle MRI. In a subgroup of 15 patients we correlated the muscle MRI findings with the histology of open extensor digitorum brevis (EDB) muscle biopsies. Muscle MRI involvement was assigned using a scale 0–4 (normal–severe). Results: In all patients we documented a gradient of involvement of the lower leg muscles: the posterior compartment (gastrocnemius > soleus) was most severely affected; the anterior compartment (tibialis anterior/posterior, popliteus, extensor digitorum longus) least affected. Muscle MRI showed EDB involvement that correlated with the patient's age (p = 0.055). We show a correlation between the MRI and EDB histopathologic changes, with MRI 3–4 grades associated with a more severe fibro-adipose tissue replacement. The EDB was sufficiently preserved for bulk and signal intensity in 18/22 wheelchair users aged 10–16.6 years. Conclusion: This study provides a detailed correlation between muscle histology and MRI changes in DMD and demonstrates the value of this imaging technique as a reliable tool for the selection of muscles in patients recruited into clinical trials.
Kinali, M.; Arechavala-Gomeza, V.; Cirak, S.; Glover, A.; Guglieri, M.; Feng, L.; Hollingsworth, K.G.; Hunt, D.; Jungbluth, H.; Roper, H.P.; Quinlivan, R.M.; Gosalakkal, J.A.; Jayawant, S.; Nadeau, A.; Hughes-Carre, L.; Manzur, A.Y.; Mercuri, E.; Morgan, J.E.; Straub, V.; Bushby, K.; Sewry, C.; Rutherford, M.
The presence of non-progressive cognitive impairment is recognized as a common feature in a substantial proportion of patients with Duchenne muscular dystrophy (DMD). Concurrently, the amyloid beta peptide (A?42) protein has been associated with changes in memory and cognitive functions. Also, it has been shown that different subtypes of neural stem/progenitor cells (CD 34, CD 45, nestin) are involved in the innate repair of plasticity mechanisms by the injured brain, in which Nerve Growth Factor (NGF) acts as chemotactic agents to recruit such cells. Accordingly, the present study investigated levels of CD 34, CD 45, nestin and NGF in an attempt to investigate makers of neural regeneration in DMD. Neural damage was assayed in terms of A?42. Results showed that A?42 (21.9 ± 6.7 vs. 12.13 ± 4.5) was significantly increased among DMD patients compared to controls. NGF (165.8 ± 72 vs. 89.8 ± 35.9) and mononuclear cells expressing nestin (18.9 ± 6 vs. 9 ± 4), CD 45 (64 ± 5.4 vs. 53.3 ± 5.2) and CD34 (75 ± 6.2 vs. 60 ± 4.8) were significantly increased among DMD patients compared to controls. In conclusion cognitive function decline in DMD patients is associated with increased levels of A?42, which is suggested to be the cause of brain damage in such patients. The significant increase plasma NFG and in the number of mononuclear cells bearing CD34, CD45 and nestin indicates that regeneration is an ongoing process in these patients. However, this regeneration cannot counterbalance the damage induced by dystrophine mutation and increased A?42. PMID:24843230
Salam, Ekram Abdel; Abdel-Meguid, Iman Ehsan; Shatla, Rania; Korraa, Soheir
Duchenne muscular dystrophy (DMD) is a progressive pediatric disorder that affects both muscle and brain. Children with DMD have mean IQ scores that are about one standard deviation lower than population means, with lower Verbal IQ than Performance IQ scores. For the present study, verbal skills and verbal memory skills were examined in males with DMD with the Clinical Evaluation of Language Fundamentals, 3rd edition, and the California Verbal Learning Test for Children. Performance of 50 males with DMD (age range 6–14y, mean 9y 4mo [SD 2y 1mo]) was compared to normative values. Two subsets of the probands were also compared with two comparison groups: unaffected siblings (n=24; DMD group age range 6–12y, mean 9y 1mo [SD 1y 8mo]; sibling age range 6–15y, mean 9y 11mo [SD 2y 4mo]) and males with cerebral palsy (CP); (n=23; DMD group age range 6–9y, mean 7y 8mo [SD 1y 2mo]; CP age range 6–8y, mean 6y 8mo [SD 0y 8mo]). Results demonstrated that although males with DMD performed slightly more poorly than normative values, they performed comparably to the controls on most measures. Consistent deficits were observed only on tests requiring immediate repetition for verbal material (Recalling Sentences, and Concepts and Directions). On other language tasks, including tests of understanding and use of grammar, and understanding of semantic relationships, the males with DMD performed well. Moreover, the males with DMD performed well on multiple indices of verbal recall, and there was no evidence of declarative memory deficits. DMD is a single-gene disorder that is selectively associated with decreased verbal span capacity, but not impaired recall.
Hinton, V J; BA, R J Fee; Goldstein, E M; De Vivo, D C
Duchenne muscular dystrophy (DMD) is a progressive pediatric disorder that affects both muscle and brain. Children with DMD have mean IQ scores that are about one standard deviation lower than population means, with lower Verbal IQ than Performance IQ scores. For the present study, verbal skills and verbal memory skills were examined in males with DMD with the Clinical Evaluation of Language Fundamentals, 3rd edition, and the California Verbal Learning Test for Children. Performance of 50 males with DMD (age range 6–14y, mean 9y 4mo [SD 2y 1mo]) was compared to normative values. Two subsets of the probands were also compared with two comparison groups: unaffected siblings (n=24; DMD group age range 6–12y, mean 9y 1mo [SD 1y 8mo]; sibling age range 6–15y, mean 9y 11mo [SD 2y 4mo]) and males with cerebral palsy (CP);(n=23; DMD group age range 6–9y, mean 7y 8mo [SD 1y 2mo]; CP age range 6–8y, mean 6y 8mo [SD 0y 8mo]). Results demonstrated that although males with DMD performed slightly more poorly than normative values, they performed comparably to the controls on most measures. Consistent deficits were observed only on tests requiring immediate repetition for verbal material (Recalling Sentences, and Concepts and Directions). On other language tasks, including tests of understanding and use of grammar, and understanding of semantic relationships, the males with DMD performed well. Moreover, the males with DMD performed well on multiple indices of verbal recall, and there was no evidence of declarative memory deficits. DMD is a single-gene disorder that is selectively associated with decreased verbal span capacity, but not impaired recall.
Hinton, V J; Fee, R J; Goldstein, E M; De Vivo, D C
Background Cardiac dysfunction in boys with Duchenne muscular dystrophy (DMD) is a leading cause of death. Cardiac resynchronization therapy (CRT) has been shown to dramatically decrease mortality in eligible adult population with congestive heart failure. We hypothesized that mechanical dyssynchrony is present in DMD patients and that cardiovascular magnetic resonance (CMR) may predict CRT efficacy. Methods DMD patients (n = 236) were stratified into 4 groups based on age, diagnosis of DMD, left ventricular (LV) ejection fraction (EF), and presence of myocardial fibrosis defined as positive late gadolinum enhancement (LGE) compared to normal controls (n = 77). Dyssynchrony indices were calculated based on timing of CMR derived circumferential strain (ecc). The calculated indices included cross-correlation delay (XCD), uniformity of strain (US), regional vector of variance (RVV), time to maximum strain (TTMS) and standard deviation (SD) of TTMS. Abnormal XCD value was defined as > normal + 2SD. US, RVV, TTMS and SD were calculated for patients with abnormal XCD. Results There was overall low prevalence of circumferential dyssynchrony in the entire DMD population; it increased to 17.1% for patients with abnormal EF and to 31.2% in the most advanced stage (abnormal EF with fibrosis). All but one DMD patient with mechanical dyssynchrony exhibited normal QRS duration suggesting absence of electrical dyssynchrony. The calculated US and RVV values (0.91 ± 0.09, 1.34 ± 0.48) indicate disperse rather than clustered dyssynchrony. Conclusion Mechanical dyssynchrony is frequent in boys with end stage DMD-associated cardiac dysfunction. It is associated with normal QRS complex as well as extensive lateral fibrosis. Based on these findings, it is unlikely that this patient population will benefit from CRT.
Duchenne muscular dystrophy (DMD) is one of the most common hereditary degenerative neuromuscular diseases and caused by mutations in the dystrophin gene. The objective of the retrospective study was to describe growth and psychomotor development of patients with DMD and to detect a possible genotype-phenotype correlation. Data from 263 patients with DMD (mean age 7.1 years) treated at the Departments of Pediatric Neurology in three German University Hospitals was assessed with respect to body measurements (length, weight, body mass index BMI, head circumference OFC), motor and cognitive development as well as genotype (site of mutation). Anthropometric measures and developmental data were compared to those of a reference population and deviations were analyzed for their frequency in the cohort as well as in relation to the genotypes. Corticosteroid therapy was implemented in 29 from 263 patients. Overall 30% of the patients exhibit a short statue (length < 3rd centile) with onset early in development at 2-5 years of age, and this is even more prevalent when steroid therapy is applied (45% of patients with steroid therapy). The BMI shows a rightwards shift (68% > 50th centile) and the OFC a leftwards shift (65% < 50th centile, 5% microcephaly). Gross motor development is delayed in a third of the patients (mean age at walking 18.3 months, 30% > 18 months, 8% > 24 months). Almost half of the patients show cognitive impairment (26% learning disability, 17% intellectual disability). Although there is no strict genotype-phenotype correlation, particularly mutations in the distal part of the dystrophin gene are frequently associated with short stature and a high rate of microcephaly as well as cognitive impairment. PMID:24100172
Sarrazin, Elisabeth; von der Hagen, Maja; Schara, Ulrike; von Au, Katja; Kaindl, Angela M
Dystrophin, the protein product of the Duchenne muscular dystrophy (DMD) gene, was studied in 19 patients with Xp21 disorders and in 25 individuals with non-Xp21 muscular dystrophy. Antibodies raised to seven different regions spanning most of the protein were used for immunocytochemistry. In all patients specific dystrophin staining anomalies were detected and correlated with clinical severity and also gene deletion. In patients with Becker muscular dystrophy (BMD) the anomalies detected ranged from inter- and intra-fibre variation in labelling intensity with the same antibody or several antibodies to general reduction in staining and discontinuous staining. In vitro evidence of abnormal dystrophin breakdown was observed reanalysing the muscle of patients, with BMD and not that of non-Xp21 dystrophies, after it has been stored for several months. A number of patients with DMD showed some staining but this did not represent a diagnostic problem. Based on the data presented, it was concluded that immunocytochemistry is a powerful technique in the prognostic diagnosis of Xp21 muscular dystrophies. Images
Muntoni, F; Mateddu, A; Cianchetti, C; Marrosu, M G; Clerk, A; Cau, M; Congiu, R; Cao, A; Melis, M A
Ullrich congenital muscular dystrophy is a severe genetically and clinically heterogeneous muscle disorder linked to collagen VI deficiency. The pathogenesis of the disease is unknown. To assess the potential role of mitochondrial dysfunction in the onset of muscle fiber death in this form of dystrophy, we studied biopsies and myoblast cultures obtained from patients with different genetic defects of collagen VI and variable clinical presentations of the disease. We identified a latent mitochondrial dysfunction in myoblasts from patients with Ullrich congenital muscular dystrophy that matched an increased occurrence of spontaneous apoptosis. Unlike those in myoblasts from healthy donors, mitochondria in cells from patients depolarized upon addition of oligomycin and displayed ultrastructural alterations that were worsened by treatment with oligomycin. The increased apoptosis, the ultrastructural defects, and the anomalous response to oligomycin could be normalized by Ca2+ chelators, by plating cells on collagen VI, and by treatment with cyclosporin A or with the specific cyclophilin inhibitor methylAla3ethylVal4-cyclosporin, which does not affect calcineurin activity. Here we demonstrate that mitochondrial dysfunction plays an important role in muscle cell wasting in Ullrich congenital muscular dystrophy. This study represents an essential step toward a pharmacological therapy of Ullrich congenital muscular dystrophy with cyclosporin A and methylAla3ethylVal4 cyclosporin.
Angelin, Alessia; Tiepolo, Tania; Sabatelli, Patrizia; Grumati, Paolo; Bergamin, Natascha; Golfieri, Cristina; Mattioli, Elisabetta; Gualandi, Francesca; Ferlini, Alessandra; Merlini, Luciano; Maraldi, Nadir M.; Bonaldo, Paolo; Bernardi, Paolo
Becker muscular dystrophy features progressive proximal weakness, wasting and often focal hypertrophy. We present a patient with pain and cramps from adolescence. Widespread muscle hypertrophy, preserved muscle strength and a 10-20-fold raised CPK were noted. Muscle biopsy was dystrophic, and Western blot showed a 95% reduction of dystrophin levels. Genetic analyses revealed a non-sense mutation in exon 2 of the dystrophin gene. This mutation is predicted to result in a Duchenne phenotype, but resulted in a mild Becker muscular dystrophy with widespread muscle hypertrophy. We suggest that this unusual phenotype is caused by translation re-initiation downstream from the mutation site. PMID:22939275
Witting, N; Duno, M; Vissing, J
Two siblings were evaluated for progressive proximal weakness and elevated creatine kinase. Immunohistochemical staining in the brother's muscle biopsy showed near absence of all four sarcoglycan subunits. Clinical progression prompted a trial of deflazacort in both siblings. At 22 months of drug therapy, both patients have stable or improved strength testing. Further analysis on the muscle biopsy revealed homozygous beta-sarcoglycan gene mutation (S114F), consistent with the limb-girdle muscular dystrophy type 2E (LGME 2E). Despite the severe phenotype, deflazacort has a beneficial effect on slowing disease progression in LGME 2E similar to that seen in Duchenne muscular dystrophy. PMID:20071171
Wong-Kisiel, Lily C; Kuntz, Nancy L
Background Currently, clinical trials for new therapeutic strategies are being planned for Duchenne and Becker muscular dystrophies (DMD/BMD). However, it is difficult to obtain adequate numbers of patients in clinical trials. As solutions to these problems, patient registries are an important resource worldwide, especially in rare diseases such as DMD/BMD. Methods We developed a national registry of Japanese DMD/BMD patients in collaboration with TREAT-NMD. The registry includes male Japanese DMD/BMD patients whose genetic status has been confirmed by genetic analysis. The registry includes patients throughout Japan. Results As of February 2012, 583 DMD and 105 BMD patients were registered. Most individuals aged less than 20 years. In terms of genetic mutations of registrants of DMD and BMD, deletion of exons was the most frequent (61.4% and 79.0%) followed by point mutations (24.5% and 14.3%) and duplications (13.6% and 4.8%), respectively. 43.6% of DMD are capable of walking, and 76.2% of BMD registrants are able to walk. 41.1% of DMD registrants in the database were treated using steroids. 29.5% of DMD and 23.8% of BMD registrants were prescribed one cardiac medicine at least. 22% of DMD used ventilator support, and non-invasive support was common. Small numbers of DMD and BMD registrants, only 3.9% and 1.0% of them, have received scoliosis surgery. 57 (9.8%) patients were eligible to clinical trial focused on ‘skipping’ exon 51. Conclusions The Remudy has already demonstrated utility in clinical researches and standardization of patients care for DMD/BMD. This new DMD/BMD patient registry facilitates the synchronization of clinical drug development in Japan with that in other countries.
Background: Merosin-deficient congenital muscular dystrophy (CMD) is characterized clinically by hypotonia and muscular weakness and, on imaging studies, by white matter (WM) abnormality. Objective: To evaluate MRI findings in Brazilian patients with merosin-deficient CMD. Materials and methods: Twenty-five patients were evaluated using MRI. Three patients presented with partial merosin deficiency and 22 with total merosin deficiency. Follow-up examinations were done
Claudia C. Leite; Leandro T. Lucato; Maria G. M. Martin; Lucio G. Ferreira; Maria B. D. Resende; Mary S. Carvalho; Suely K. N. Marie; J. Randy Jinkins; Umbertina C. Reed
Members of the caveolin family are the main component of caveolae, and caveolin-3 is a muscle-specific protein. Caveolin-3 deficiency induces a muscular dystrophic phenotype, while its overexpression is also harmful to muscle cells. Increased caveolae were observed in chicken muscular dystrophy; however, the underlying mechanism causing the onset remains unclear. Therefore, the current study analyzes the expression of caveolin-3 and
Hirokazu Matsumoto; Shinji Sasazaki; Akira Fujiwara; Nobutsune Ichihara; Tateki Kikuchi; Hideyuki Mannen
Context Myotonic muscular dystrophy (MMD) is an autosomal dominant multisystem neuromuscular disorder characterized by unstable nucleotide repeat expansions. Case reports have suggested that MMD patients may be at increased risk of malignancy, putative risks which have never been quantified. Objective To quantitatively evaluate cancer risk in patients with MMD, overall, and by sex and age. Design, Setting, and Participants We identified 1,658 patients with an MMD discharge diagnosis in the Swedish Inpatient Hospital or Danish Patient Discharge Registries between 1977 and 2008. We linked these patients to their corresponding cancer registry. Patients were followed from date of first MMD-related inpatient or outpatient contact, to first cancer diagnosis, death, emigration, or completion of cancer registration. Main Outcome Measures Risks of all cancers combined, and by anatomic site, stratified by sex and age. Results 104 patients with an inpatient or outpatient discharge diagnosis of MMD developed cancer during post-discharge follow-up. This corresponds to an observed cancer rate of 73.4/10,000 person-years in MMD versus an expected rate of 36.9/10,000 in the general Swedish and Danish populations combined (SIR =2.0, 95% CI =1.6–2.4). Specifically, we observed significant excess risks of cancers of the endometrium (observed rate=16.1/10,000 person-years: SIR=7.6, 95%CI=4.0–13.2), brain (observed rate=4.9/10,000 person-years: SIR=5.3, 95%CI=2.3–10.4), ovary (observed rate=10.3/10,000 person-years: SIR=5.2, 95% CI=2.3–10.2), and colon (observed rate=7.1/10,000 person-years: SIR=2.9, 95%CI=1.5–5.1). Cancer risks were similar in females and males after excluding genital organ tumors (SIR=1.9, 95% CI=1.4–2.5 vs. 1.8, 95% CI=1.3–2.5, respectively, p-heterogeneity=0.81; observed rates=64.5 and 47.7/10,000 person-years in women and men, respectively), The same pattern of cancer excess was observed first in the Swedish, and then in the Danish cohorts, which were studied sequentially and initially analyzed independently. Conclusions MMD patients identified from the Swedish and Danish patient registries were at increased risk of cancer both overall and for selected anatomic sites.
Gadalla, Shahinaz M; Lund, Marie; Pfeiffer, Ruth M; G?rtz, Sanne; Mueller, Christine M; Moxley, Richard T; Kristinsson, Sigurdur Y; Bjorkholm, Magnus; Shebl, Fatma M; Hilbert, James E; Landgren, Ola; Wohlfahrt, Jan; Melbye, Mads; Greene, Mark H
Background Although previous studies have helped define the natural history of Duchenne Muscular Dystrophy (DMD)-associated cardiomyopathy, the myocardial pathobiology associated with functional impairment in DMD is not yet known. The objective of this study was to assess the distribution of transverse relaxation time (T2) in the left ventricle (LV) of DMD patients, and to determine the association of myocardial T2 heterogeneity to the severity of cardiac dysfunction. DMD patients (n = 26) and normal control subjects (n = 13) were studied by Cardiovascular Magnetic Resonance (CMR). DMD subject data was stratified based on subject age and LV Ejection Fraction (EF) into the following groups: A (<12 years old, n = 12); B (?12 years old, EF ? 55%, n = 8) and C (?12 years old, EF = 55%, n = 6). Controls were also stratified by age into Groups N1 (<12 years, n = 6) and N2 (>12 years, n = 5). LV mid-slice circumferential myocardial strain (?cc) was calculated using tagged CMR imaging. T2 maps of the LV were generated for all subjects using a black blood dual spin echo method at two echo times. The Full Width at Half Maximum (FWHM) was calculated from a histogram of LV T2 distribution constructed for each subject. Results In DMD subject groups, FWHM of the T2 histogram rose progressively with age and decreasing EF (Group A FWHM= 25.3 ± 3.8 ms; Group B FWHM= 30.9 ± 5.3 ms; Group C FWHM= 33.0 ± 6.4 ms). Further, FWHM was significantly higher in those with reduced circumferential strain (|?cc| ? 12%) (Group B, and C) than those with |?cc| > 12% (Group A). Group A FWHM was not different from the two normal groups (N1 FWHM = 25.3 ± 3.5 ms; N2 FWHM= 24.0 ± 7.3 ms). Conclusion Reduced EF and ?cc correlates well with increased T2 heterogeneity quantified by FWHM, indicating that subclinical functional impairments could be associated with pre-existing abnormalities in tissue structure in young DMD patients.
The muscular dystrophies show muscle degeneration and regeneration (necrotizing myopathy) on muscle biopsy, typically associated with elevated serum creatine kinase, and muscle weakness. In 1986, the first causative gene was identified for the most prevalent and best-characterized form of muscular dystrophy, Duchenne muscular dystrophy. Over the past 25 years, the number of other genes determined to cause different subtypes has grown rapidly. This review gives a synopsis of the 45 genetically defined types of muscular dystrophies and describes the clinical, pathologic, and molecular aspects of each disease. DNA diagnosis remains the most sensitive and specific method for differential diagnosis, but molecular diagnostics can be expensive and complex (because of multiple genes at multiple testing facilities) and reimbursement may be challenging to obtain. However, emerging DNA sequencing technologies (eg, single-molecule thirdgeneration sequencing units) promise to dramatically reduce the complexity and costs of DNA diagnostics. Treatment for nearly all forms remains supportive and is aimed at preventing complications. However, several promising approaches have entered clinical trials, providing tangible hope that quality of life will improve for many patients in the near future.
Rocha, Carolina Tesi; Hoffman, Eric P.
Diagnosis of limb girdle muscular dystrophy type 2A can be complex due to phenotypic variability, lack of precision of protein analysis in muscle biopsies, and absence of mutational hot spots in the CAPN3 gene. The aim of this study was to review clinical and biopsy data from a group of patients with known CAPN3 genetic status to validate and refine
Emma J. Groen; Richard Charlton; Rita Barresi; Louise V. Anderson; Michelle Eagle; Judith Hudson; Mauro Santibanez Koref; Volker Straub; Katharine M. D. Bushby
Plectin is a cytoskeletal linker protein which has a long central rod and N- and C-terminal globular domains. Mutations in the gene encoding plectin (PLEC) cause two distinct autosomal recessive subtypes of epidermolysis bullosa: EB simplex (EBS) with muscular dystrophy (EBS-MD), and EBS with pyloric atresia (EBS-PA). Previous studies have demonstrated that loss of full-length plectin with residual expression of the rodless isoform leads to EBS-MD, whereas complete loss or marked attenuation of expression of full-length and rodless plectin underlies the more severe EBS-PA phenotype. However, muscular dystrophy has never been identified in EBS-PA, not even in the severe form of the disease. Here, we report the first case of EBS associated with both pyloric atresia and muscular dystrophy. Both of the premature termination codon-causing mutations of the proband are located within exon 32, the last exon of PLEC. Immunofluorescence and immunoblot analysis of skin samples and cultured fibroblasts from the proband revealed truncated plectin protein expression in low amounts. This study demonstrates that plectin deficiency can indeed lead to both muscular dystrophy and pyloric atresia in an individual EBS patient. PMID:20665883
Natsuga, Ken; Nishie, Wataru; Shinkuma, Satoru; Arita, Ken; Nakamura, Hideki; Ohyama, Makiko; Osaka, Hitoshi; Kambara, Takeshi; Hirako, Yoshiaki; Shimizu, Hiroshi
A novel form of congenital muscular dystrophy in four unrelated patients is proposed. Congenital hypotonia, markedly increased CK, calf pseudohypertrophy and proximal weakness were common early findings. Two cases were severely affected since infancy and never walked. The phenotypical homogeneity was not very evident until advanced stages of the disease. All the patients showed catastrophic progression of the weakness, severe
Susana Quijano-Roy; Luc??a Galan; Ana Ferreiro; Fawzia Cheliout-Héraut; Françoise Gray; Michel Fardeau; Annie Barois; Pascale Guicheney; Norma B Romero; Brigitte Estournet
Introduction: Duchenne muscular dystrophy (DMD) is a severe muscle degenerative disorder caused by mutations in the dystrophin gene. Embryonic stem cell (ES cell) transplantation is one of the more promising therapies because ES cells are available in large quantities and can serve to systemically restore affected muscles of DMD patients. Although ES cells have shown to be capable of differentiating
Shiro Ozasa; Shigemi Kimura; Makoto Matsukura; Kaori Ito; Makoto Ikezawa; Hiroe Kawano; Teruhisa Miike; Kenichi Yamamura; Kimi Araki; Kuniya Abe; Hitoshi Niwa
Several forms of congenital muscular dystrophy, referred to as dystroglycanopathies, result from defects in the protein O-mannosylation biosynthetic pathway. In this minireview, I discuss 12 proteins involved in the pathway and how they play a role in the building of glycan structures (most notably on the protein ?-dystroglycan) that allow for binding to multiple proteins of the extracellular matrix.
Unregulated Ca(2+) entry is thought to underlie muscular dystrophy. Here, we generated skeletal-muscle-specific transgenic (TG) mice expressing the Na(+)-Ca(2+) exchanger 1 (NCX1) to model its identified augmentation during muscular dystrophy. The NCX1 transgene induced dystrophy-like disease in all hind-limb musculature, as well as exacerbated the muscle disease phenotypes in ?-sarcoglycan (Sgcd(-/-)), Dysf(-/-), and mdx mouse models of muscular dystrophy. Antithetically, muscle-specific deletion of the Slc8a1 (NCX1) gene diminished hind-limb pathology in Sgcd(-/-) mice. Measured increases in baseline Na(+) and Ca(2+) in dystrophic muscle fibers of the hind-limb musculature predicts a net Ca(2+) influx state due to reverse-mode operation of NCX1, which mediates disease. However, the opposite effect is observed in the diaphragm, where NCX1 overexpression mildly protects from dystrophic disease through a predicted enhancement in forward-mode NCX1 operation that reduces Ca(2+) levels. Indeed, Atp1a2(+/-) (encoding Na(+)-K(+) ATPase ?2) mice, which have reduced Na(+) clearance rates that would favor NCX1 reverse-mode operation, showed exacerbated disease in the hind limbs of NCX1 TG mice, similar to treatment with the Na(+)-K(+) ATPase inhibitor digoxin. Treatment of Sgcd(-/-) mice with ranolazine, a broadly acting Na(+) channel inhibitor that should increase NCX1 forward-mode operation, reduced muscular pathology. PMID:24662047
Burr, Adam R; Millay, Douglas P; Goonasekera, Sanjeewa A; Park, Ki Ho; Sargent, Michelle A; Collins, James; Altamirano, Francisco; Philipson, Kenneth D; Allen, Paul D; Ma, Jianjie; López, José Rafael; Molkentin, Jeffery D
Autophagy is crucial in the turnover of cell components, and clearance of damaged organelles by the autophagic-lysosomal pathway is essential for tissue homeostasis. Defects of this degradative system have a role in various diseases, but little is known about autophagy in muscular dystrophies. We have previously found that muscular dystrophies linked to collagen VI deficiency show dysfunctional mitochondria and spontaneous apoptosis, leading to myofiber degeneration. Here we demonstrate that this persistence of abnormal organelles and apoptosis are caused by defective autophagy. Skeletal muscles of collagen VI-knockout (Col6a1(-/-)) mice had impaired autophagic flux, which matched the lower induction of beclin-1 and BCL-2/adenovirus E1B-interacting protein-3 (Bnip3) and the lack of autophagosomes after starvation. Forced activation of autophagy by genetic, dietary and pharmacological approaches restored myofiber survival and ameliorated the dystrophic phenotype of Col6a1(-/-) mice. Furthermore, muscle biopsies from subjects with Bethlem myopathy or Ullrich congenital muscular dystrophy had reduced protein amounts of beclin-1 and Bnip3. These findings indicate that defective activation of the autophagic machinery is pathogenic in some congenital muscular dystrophies. PMID:21037586
Grumati, Paolo; Coletto, Luisa; Sabatelli, Patrizia; Cescon, Matilde; Angelin, Alessia; Bertaggia, Enrico; Blaauw, Bert; Urciuolo, Anna; Tiepolo, Tania; Merlini, Luciano; Maraldi, Nadir M; Bernardi, Paolo; Sandri, Marco; Bonaldo, Paolo
Mutations in the dystrophin gene give rise to Duchenne and Becker muscular dystrophies (DMD and BMD), in which both skeletal and cardiac muscles are affected, but also to X-linked dilated cardiomyopathy (XLDC), a condition characterised by exclusive cardiac involvement. XLDC patients with mutations at the 5? end of the gene typically have a cardiac specific severe transcriptional pathology, with absent
Marcella Neri; Silvia Torelli; Sue Brown; Isabella Ugo; Patrizia Sabatelli; Luciano Merlini; Pietro Spitali; Paola Rimessi; Francesca Gualandi; Caroline Sewry; Alessandra Ferlini; Francesco Muntoni
We report on a male patient aged 38, affected by a syndrome whose characteristic features include onset in early childhood, slow progression, diffuse muscle weakness, mental retardation and cardiomyopathy. Muscle biopsy showed myopathic changes compatible with muscular dystrophy. However, immunostaining for dystrophin as well as 50 and 43 kDa dystrophin-associated glycoproteins (DAGs) was normal. Genetic analysis suggested that direct involvement
M. Villanova; A. Malandrini; R. Biancotti; A. Löfgren; T. Mongini; R. Salvestroni; E. Parrotta; C. Van Broeckhoven; C. Paolozzi; G. Guazzi
Duchenne's muscular dystrophy (DMD) is a severe progressive myopathy caused by mutations in the DMD gene leading to a deficiency of the dystrophin protein. Due to ongoing muscle necrosis in respiratory muscles late-stage DMD is associated with respiratory insufficiency and chronic hypoxia (CH). To understand the effects of CH on dystrophin-deficient muscle in vivo, we exposed the Drosophila model for
Matias Mosqueira; Gabriel Willmann; Hannele Ruohola-Baker; Tejvir S. Khurana; Jose A. L. Calbet
An inherited form of muscular dystrophy in chickens has been used as a model of Duchenne muscular dystrophy. The pectoralis major muscle of chickens with this disease showed a significantly elevated activity of catalase (CAT) one day after hatching, and by 7 days showed elevated superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione-S-transferase (GST) activities. Increases were also found in tissues of the dystrophic birds that, unlike the pectoralis muscle, are considered to be unaffected by the pathology of muscular dystrophy. The soleus muscle contained significantly increased levels of SOD and GPX in 1 and 7 day old chickens, and increased GST in 1, 14, and 28 day old birds. CAT was significantly increased in liver from 1 and 7 day old chickens, while GPX was increased in lung from 1, 7 and 14 day old birds. These results support the possibility that excess oxygen free-radicals or altered cellular antioxidant defenses play some role in the pathogenesis of muscular dystrophy. PMID:3947339
Murphy, M E; Kehrer, J P
We studied surgical experiences within a regional cohort of patients with Duchenne muscular dystrophy, managed at a single center. Records of all patients with confirmed Duchenne muscular dystrophy who were born after 1962 were reviewed from birth until they reached study endpoints: scoliosis surgery, Achilles tendon lengthening, cataract surgery, loss to follow-up, or final follow-up point in 2009. A survival analysis was used to account for the variable follow-up duration within this cohort. By the end of the study period, 28/80 (35.0%) of boys with Duchenne muscular dystrophy had undergone spinal surgery, 22/80 (27.5%) had experienced Achilles tendon lengthening, and 6/80 (7.5%) had had cataracts removed. Moreover, 56.8% of this cohort received steroid therapy (prednisone or deflazacort; 95% confidence interval, 43.3-68.8%). Boys who had received steroid therapy were significantly less likely to undergo spinal surgery (P = 0.001), but were subsequently more likely to require cataract surgery (P = 0.005). Achilles tendon lengthening did not seem related to medication exposure. The treatment of patients with Duchenne muscular dystrophy with steroids significantly modified their surgical experience. PMID:20691938
Dooley, Joseph M; Gordon, Kevin E; MacSween, Judith M
Albeit genetically highly heterogeneous, muscular dystrophies (MDs) share a convergent pathology leading to muscle wasting accompanied by proliferation of fibrous and fatty tissue, suggesting a common MD–pathomechanism. Here we show that mutations in muscular dystrophy genes (Dmd, Dysf, Capn3, Large) lead to the spontaneous formation of skeletal muscle-derived malignant tumors in mice, presenting as mixed rhabdomyo-, fibro-, and liposarcomas. Primary MD–gene defects and strain background strongly influence sarcoma incidence, latency, localization, and gender prevalence. Combined loss of dystrophin and dysferlin, as well as dystrophin and calpain-3, leads to accelerated tumor formation. Irrespective of the primary gene defects, all MD sarcomas share non-random genomic alterations including frequent losses of tumor suppressors (Cdkn2a, Nf1), amplification of oncogenes (Met, Jun), recurrent duplications of whole chromosomes 8 and 15, and DNA damage. Remarkably, these sarcoma-specific genetic lesions are already regularly present in skeletal muscles in aged MD mice even prior to sarcoma development. Accordingly, we show also that skeletal muscle from human muscular dystrophy patients is affected by gross genomic instability, represented by DNA double-strand breaks and age-related accumulation of aneusomies. These novel aspects of molecular pathologies common to muscular dystrophies and tumor biology will potentially influence the strategies to combat these diseases.
Schmidt, Wolfgang M.; Uddin, Mohammed H.; Dysek, Sandra; Moser-Thier, Karin; Pirker, Christine; Hoger, Harald; Ambros, Inge M.; Ambros, Peter F.; Berger, Walter; Bittner, Reginald E.
Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are X-linked recessive disorders caused by mutations of the DMD gene located at Xp21. In DMD patients, dystrophin is virtually absent; whereas BMD patients have 10% to 40% of the normal amount. Deletions in the dystrophin gene represent 65% of mutations in DMD/BMD patients. To explain the contribution of immunohistochemical and genetic analysis in the diagnosis of these dystrophies, we present 10 cases of DMD/BMD with particular features. We have analyzed the patients with immunohistochemical staining and PCR multiplex to screen for exons deletions. Determination of the quantity and distribution of dystrophin by immunohistochemical staining can confirm the presence of dystrophinopathy and allows differentiation between DMD and BMD, but dystrophin staining is not always conclusive in BMD. Therefore, only identification involved mutation by genetic analysis can establish a correct diagnosis.
Bellayou, Hanane; Hamzi, Khalil; Rafai, Mohamed Abdou; Karkouri, Mehdi; Slassi, Ilham; Azeddoug, Houssine; Nadifi, Sellama
Mutations in the PLEC1 gene encoding plectin have been reported in neonatal epidermolysis bullosa simplex with muscular dystrophy of later-onset (EBS-MD). A neuromuscular transmission defect has been reported in one previous patient. We report a boy presenting from birth with features of a congenital muscular dystrophy and late-onset myasthenic symptoms. Repetitive nerve stimulation showed significant decrement, and strength improved with pyridostigmine. Subtle blistering noticed only retrospectively prompted further genetic testing, revealing recessive PLEC1 mutations. We conclude that PLEC1 should be considered in the differential diagnosis of congenital muscular dystrophies and myasthenic syndromes, even in the absence of prominent skin involvement. PMID:20624679
Forrest, Katharine; Mellerio, Jemima E; Robb, Stephanie; Dopping-Hepenstal, Patricia J C; McGrath, John A; Liu, Lu; Buk, Stefan J A; Al-Sarraj, Safa; Wraige, Elizabeth; Jungbluth, Heinz
Facioscapulohumeral muscular dystrophy (FSHD) is a neuromuscular disorder often considered to be the third most common muscular dystrophy. Deletions reducing the copy number of the D4Z4 repeat in the distal end of the 4q arm are the main genetic cause of the disease. The recently highlighted research has identified a transcriptional activatory long non-coding RNA involved in the disease that acts through the recruitment of ASH1L, a protein belonging to the Trithorax family. PMID:22710800
Vizoso, Miguel; Esteller, Manel
Objective:A systematic review of the available literature on the effectiveness of knee-ankle-foot orthoses in the treatment of Duchenne muscular dystrophy.Design:A computer search was carried out (MEDLINE 1966–97, CINAHL 1982–97) using the key words muscular dystrophy, rehabilitation, locomotion, braces or orthotic devices. References in relevant publications and nonindexed journals were also examined. Criteria to include and exclude articles were formulated. We
J. P. J. Bakker; I J M de Groot; H. Beckerman-Boiten; B A de Jong; G. J. Lankhorst
Mutations in the dystrophin gene result in both Duchenne and Becker muscular dystrophies (DMD and BMD). Approximately two-thirds of the affected patients have large deletions or duplications. Using the multiplex polymerase chain reaction and Southern blotting techniques, the detection of these larger mutations is relatively straightforward. Detection of the point mutations in the remaining one-third of the patients has been challenging, mainly due to the large gene size and lack of hotspots or prevalent mutations. However, with the addition of some of the newer molecular screening methods, it is becoming more feasible for clinical laboratories to test for point mutations in the larger genes like dystrophin. Here we review the clinical features, describe the mutation distributions, evaluate current molecular strategies, and illustrate how the genetic findings have impacted the current clinical diagnostics of Duchenne and Becker muscular dystrophies.
Prior, Thomas W.; Bridgeman, Scott J.
Corticosteroids have recently been shown to reduce expected loss of muscle strength in patients with Duchenne muscular dystrophy and extend the time they can walk. We evaluated 43 boys with the condition to determine whether taking corticosteroids is associated with differences in gait pattern, gross motor skills, energy efficiency, and timed motor performance. We used the gait deviation index to quantify the degree of gait pathology and a single measure of gait quality. There were minimal differences in gait pattern, gross motor skills, energy efficiency, or timed motor performance in boys who took corticosteroids compared with those who did not. Clustering by gait deviation index, however, revealed subtle differences between groups in gait patterns, gross motor skills, and energy efficiency. We conclude that, in boys with Duchenne muscular dystrophy, gait pattern deviations are related to function, which can provide further insight into the understanding of disease progression and treatment options to enhance function and maintain ambulation.
Thomas, Susan Sienko; Buckon, Cathleen E.; Nicorici, Alina; Bagley, Anita; McDonald, Craig M.; Sussman, Michael D.
The polymerase chain reaction (PCR) was used on material from a blighted ovum to confirm indirectly the carrier status of a woman with a family history of Becker muscular dystrophy. Conventional testing including creatine kinase levels, muscle biopsy, and EMG had been inconclusive, and on the basis of one elevated creatine kinase level, the woman had been designated a possible carrier. Ultrasound examination at 10 weeks of pregnancy indicated a blighted ovum, from which DNA was subsequently extracted and subjected to PCR testing for determination of sex and genotypic status with respect to the known familial deletion of the dystrophin gene. The blighted ovum was found to have a Y chromosome and also to be deleted for at least exon 6 of the dystrophin gene, indirectly indicating that the mother most likely carried the family mutation for Becker muscular dystrophy. PMID:8284293
Wilton, S D; Goldblatt, J; Laing, N G
Duchenne muscular dystrophy is a progressive and incurable neuromuscular disease caused by genetic and biochemical defects of the dystrophin-glycoprotein complex. Here we show the regenerative potential of myogenic progenitors derived from corrected dystrophic induced pluripotent stem cells generated from fibroblasts of mice lacking both dystrophin and utrophin. We correct the phenotype of dystrophic induced pluripotent stem cells using a Sleeping Beauty transposon system carrying the micro-utrophin gene, differentiate these cells into skeletal muscle progenitors and transplant them back into dystrophic mice. Engrafted muscles displayed large numbers of micro-utrophin-positive myofibers, with biochemically restored dystrophin-glycoprotein complex and improved contractile strength. The transplanted cells seed the satellite cell compartment, responded properly to injury and exhibit neuromuscular synapses. We also detect muscle engraftment after systemic delivery of these corrected progenitors. These results represent an important advance towards the future treatment of muscular dystrophies using genetically corrected autologous induced pluripotent stem cells. PMID:23462992
Filareto, Antonio; Parker, Sarah; Darabi, Radbod; Borges, Luciene; Iacovino, Michelina; Schaaf, Tory; Mayerhofer, Timothy; Chamberlain, Jeffrey S; Ervasti, James M; McIvor, R Scott; Kyba, Michael; Perlingeiro, Rita C R
Introduction: The correlation of markers of disease severity among brothers with Duchenne or Becker muscular dystrophy has implications for clinical guidance and clinical trials. Methods: Sibling pairs with Duchenne or Becker muscular dystrophy (n = 60) were compared for ages when they reached clinical milestones of disease progression, including ceased ambulation, scoliosis of ? 20°, and development of cardiomyopathy. Results: The median age at which younger brothers reached each milestone, compared with their older brothers ranged from 25 months younger for development of cardiomyopathy to 2 months older for ceased ambulation. For each additional month of ambulation by the older brother, the hazard of ceased ambulation by the younger brother decreased by 4%. Conclusions: The ages when siblings reach clinical milestones of disease vary widely between siblings. However, the time to ceased ambulation for older brothers predicts the time to ceased ambulation for their younger brothers. Muscle Nerve 49: 814-821, 2014. PMID:24030636
Pettygrove, Sydney; Lu, Zhenqiang; Andrews, Jennifer G; Meaney, F John; Sheehan, Daniel W; Price, Elinora T; Fox, Deborah J; Pandya, Shree; Ouyang, Lijing; Apkon, Susan D; Powis, Zoe; Cunniff, Christopher
Introduction Previous studies have tested the hypothesis that calpain and/or proteasome inhibition is beneficial in Duchenne Muscular Dystrophy, based largely on evidence that calpain and proteasome activities are enhanced in the mdx mouse. Methods mRNA expression of ubiquitin proteasome and calpain system components were determined using RT-PCR in skeletal muscle and heart in the golden retriever muscular dystrophy model. Similarly, calpain 1/2 and proteasome activities were determined using fluorometric activity assays. Results We found that less than half of the muscles tested had increases in proteasome activity, and only one-half had increased calpain activity. Additionally, transcriptional regulation of the ubiquitin proteasome system was most pronounced in the heart, where numerous components were significantly decreased. Discussion This study illustrates the diversity of expression and activities of the ubiquitin proteasome and calpain systems, which may lead to unexpected consequences in response to pharmacologic inhibition.
Wadosky, Kristine M.; Li, Luge; Rodriguez, Jessica E.; Min, JinNa; Bogan, Dan; Gonzalez, Jason; Patterson, Cam; Kornegay, Joe N.; Willis, Monte
Proteins of the sarcolemma are of crucial importance for the pathogenesis of muscular dystrophies. This update focuses on the dystrophin-associated proteins including the dystroglycan and sarcoglycan complexes, caveolin-3, dysferlin, and the extracellular matrix component collagen type VI. The molecular findings are correlated with some of the clinical phenotypes that are part of the limb-girdle muscular dystrophy spectrum, including fukutin-related proteinopathy (LGMD 21), the sarcoglycanopathies (LGMD 2C-F), caveolinopathy (LGMD 1C), dysferlinopathy (LGMD 2B), and finally Bethlem myopathy. Although recent progress has been tremendous, much remains to be learned about the pathophysiological consequences caused by a deficiency of any one of these components. PMID:12139001
Bönnemann, Carsten G; Finkel, Richard S
Detection of large rearrangements in the dystrophin gene in Duchenne and Becker muscular dystrophy is possible in about 65-70% of patients by Southern blotting or multiplex PCR. Subsequently, carrier detection is possible by assessing the intensity of relevant bands, but preferably by a non-quantitative test method. Detection of microlesions in Duchenne and Becker muscular dystrophy is currently under way. Single strand conformational analysis, heteroduplex analysis, and the protein truncation test are mostly used for this purpose. In this paper we review the available methods for detection of large and small mutations in patients and in carriers and propose a systematic approach for genetic analysis and genetic counselling of DMD and BMD families, including prenatal and preimplantation diagnosis. Images
van Essen, A J; Kneppers, A L; van der Hout, A H; Scheffer, H; Ginjaar, I B; ten Kate, L P; van Ommen, G J; Buys, C H; Bakker, E
Relatively few point mutations have been found in the dystrophin gene and of these only two have been associated with mosaicism. A single base insertion has been identified and quantified in a mother of two sons affected with Duchenne muscular dystrophy. It has been determined that she is a somatic mosaic with the mutation present in 25% of lymphocyte DNA. Further tissue lineages have been tested and the time at which the mutation arose was determined to be before the cellular differentiation into the bilaminar disc at approximately eight days after fertilisation. We suggest that the incidence of mosaicism for dystrophin point mutations may be higher than current data suggest.???Keywords: Duchenne muscular dystrophy; point mutation; mosaic
Smith, T.; Yau, S.; Bobrow, M.; Abbs, S.
Duchenne muscular dystrophy is an X-linked muscle disease characterized by mutations in the dystrophin gene. Many of these can be corrected at the posttranscriptional level by skipping the mutated exon. We have obtained persistent exon skipping in mdx mice by tail vein injection with an adeno-associated viral (AAV) vector expressing antisense sequences as part of the stable cellular U1 small nuclear RNA. Systemic delivery of the AAV construct resulted in effective body-wide colonization, significant recovery of the functional properties in vivo, and lower creatine kinase serum levels, suggesting an overall decrease in muscle wasting. The transduced muscles rescued dystrophin expression and displayed a significant recovery of function toward the normal values at single muscle fiber level. This approach provides solid bases for a systemic use of AAV-mediated antisense-U1 small nuclear RNA expression for the therapeutic treatment of Duchenne muscular dystrophy.
Denti, Michela Alessandra; Rosa, Alessandro; D'Antona, Giuseppe; Sthandier, Olga; De Angelis, Fernanda Gabriella; Nicoletti, Carmine; Allocca, Mariacarmela; Pansarasa, Orietta; Parente, Valeria; Musaro, Antonio; Auricchio, Alberto; Bottinelli, Roberto; Bozzoni, Irene
Recessive mutations in the ANO5 gene, encoding anoctamin 5, cause proximal limb girdle muscular dystrophy (LGMD2L), Miyoshi-type distal myopathy (MM3) and asymptomatic hyper- CKemia. We report a woman with exertion-induced myalgia and weakness in the hip girdle manifesting at the age of 40. Creatine kinase (CK) was increased 20-fold. Histologically the dominating feature was necrotizing myopathy, but long-term immunosuppressive therapy did not change CK level or myopathic symptoms. Molecular genetic investigation led to the finding of the homozygous ANO5 c.191dupA mutation. This is a report of a muscular dystrophy due to ANO5 mutation presenting histologically as necrotizing myopathy. For this reason our finding extends the histological spectrum of myopathies due to ANO5 mutations as well as the possible differential diagnoses for necrotizing myopathy. PMID:24843231
Schneider, Ilka; Stoltenburg, Gisela; Deschauer, Marcus; Winterholler, Martin; Hanisch, Frank
Abnormalities of dystrophin, the sarcoglycans, and laminin alpha2 are responsible for a subset of the muscular dystrophies. In this study we aim to characterise the nature and frequency of abnormalities of these proteins in an Australian population and to formulate an investigative algorithm to aid in approaching the diagnosis of the muscular dystrophies. To reduce ascertainment bias, biopsies with dystrophic (n=131) and non-dystrophic myopathic (n=71) changes were studied with antibodies to dystrophin, alpha, beta, and gamma sarcoglycan, beta dystroglycan, and laminin alpha2, and results were correlated with clinical phenotype. Abnormalities of dystrophin, the sarcoglycans, or laminin alpha2 were present in 61/131 (47%) dystrophic biopsies and in 0/71 myopathic biopsies, suggesting that immunocytochemical study of dystrophin, the sarcoglycans, and laminin alpha2 may, in general, be restricted to patients with dystrophic biopsies. Two patients with mutations identified in gamma sarcoglycan had abnormal dystrophin (by immunocytochemistry and immunoblot), showing that abnormalities of dystrophin may be a secondary phenomenon. Therefore, biopsies should not be excluded from sarcoglycan analysis on the basis of abnormal dystrophin alone. The diagnostic yield was highest in those with severe, rapidly progressive limb-girdle weakness (92%). Laminin alpha2 deficiency was identified in 5/131 (4%) patients; 215 patients presented after infancy, indicating that abnormalities of laminin alpha2 are not limited to the congenital muscular dystrophy phenotype. Overall patterns of immunocytochemistry and immunoblotting provided a guide to mutation analysis and, on the basis of this study, we have formulated a diagnostic algorithm to guide the investigation of patients with muscular dystrophy. Images
Jones, K J; Kim, S S; North, K N
The limb girdle muscular dystrophies (LGMDs) are a group of disorders with wide genetic and clinical heterogeneity. Recently, mutations in the ANO5 gene, which encodes a putative calcium-activated chloride channel belonging to the Anoctamin family of proteins, were identified in five families with one of two previously identified disorders, LGMD2L and non-dysferlin Miyoshi muscular dystrophy (MMD3). We screened a candidate group of 64 patients from 59 British and German kindreds and found the truncating mutation, c.191dupA in exon 5 of ANO5 in 20 patients, homozygously in 15 and in compound heterozygosity with other ANO5 variants in the rest. An intragenic SNP and an extragenic microsatellite marker are in linkage disequilibrium with the mutation, suggesting a founder effect in the Northern European population. We have further defined the clinical phenotype of ANO5-associated muscular dystrophy. Patients show adult onset proximal lower limb weakness with highly raised creatinine kinase (CK) values (average 4500 IU/l) and frequent muscle atrophy and asymmetry of muscle involvement. Onset varies from the early 20s to 50s and the weakness is generally slowly progressive, with most patients remaining ambulant for several decades. Distal presentation is much less common but a milder degree of distal lower limb weakness is often observed. Upper limb strength is only mildly affected and cardiac and respiratory function is normal. Females appear less frequently affected. In the North of England population we have identified eight patients with ANO5 mutations, suggesting a minimum prevalence of 0.27/100 000, twice as common as dysferlinopathy. We suggest that mutations in ANO5 represent a relatively common cause of adult onset muscular dystrophy with high CK and that mutation screening, particularly of the common mutation c.191dupA, should be an early step in the diagnostic algorithm of adult LGMD patients.
Muelas, Nuria; Koehler, Katrin; Huebner, Angela; Hudson, Gavin; Chinnery, Patrick F.; Barresi, Rita; Eagle, Michelle; Polvikoski, Tuomo; Bailey, Geraldine; Miller, James; Radunovic, Aleksander; Hughes, Paul J.; Roberts, Richard; Krause, Sabine; Walter, Maggie C.; Laval, Steven H.; Straub, Volker; Lochmuller, Hanns; Bushby, Kate
Limb-girdle muscular dystrophy (LGMD) 2H is a slowly progressive condition characterized by proximal weakness, atrophy, and mildly to moderately raised levels of creatine kinase. Facial weakness, scapular winging, hypertrophied calves, and Achilles tendon contractions are not uncommon and the age of onset ranges between the first and fourth decade. LGMD2H was originally described in the Hutterite population that resides in
Perry B. Shieh; Elena Kudryashova; Melissa J. Spencer
Cloned cDNA sequences representing exons from the Duchenne\\/Becker muscular dystrophy (DMD\\/BMD) gene were used for deletion screening in a population of 287 males males affected with DMD or BMD. The clinical phenotypes of affected boys were classified into three clinical severity groups based on the age at which ambulation was lost. Boys in group 1 had DMD, losing ambulation before
S Hodgson; K Hart; S Abbs; J Heckmatt; E Rodillo; M Bobrow; V Dubowitz
Dystroglycanopathies are a clinically and genetically diverse group of recessively inherited conditions ranging from the most severe of the congenital muscular dystrophies, Walker–Warburg syndrome, to mild forms of adult-onset limb-girdle muscular dystrophy. Their hallmark is a reduction in the functional glycosylation of ?-dystroglycan, which can be detected in muscle biopsies. An important part of this glycosylation is a unique O-mannosylation, essential for the interaction of ?-dystroglycan with extracellular matrix proteins such as laminin-?2. Mutations in eight genes coding for proteins in the glycosylation pathway are responsible for ?50% of dystroglycanopathy cases. Despite multiple efforts using traditional positional cloning, the causative genes for unsolved dystroglycanopathy cases have escaped discovery for several years. In a recent collaborative study, we discovered that loss-of-function recessive mutations in a novel gene, called isoprenoid synthase domain containing (ISPD), are a relatively common cause of Walker–Warburg syndrome. In this article, we report the involvement of the ISPD gene in milder dystroglycanopathy phenotypes ranging from congenital muscular dystrophy to limb-girdle muscular dystrophy and identified allelic ISPD variants in nine cases belonging to seven families. In two ambulant cases, there was evidence of structural brain involvement, whereas in seven, the clinical manifestation was restricted to a dystrophic skeletal muscle phenotype. Although the function of ISPD in mammals is not yet known, mutations in this gene clearly lead to a reduction in the functional glycosylation of ?-dystroglycan, which not only causes the severe Walker–Warburg syndrome but is also a common cause of the milder forms of dystroglycanopathy.
Cirak, Sebahattin; Foley, Aileen Reghan; Herrmann, Ralf; Willer, Tobias; Yau, Shu; Stevens, Elizabeth; Torelli, Silvia; Brodd, Lina; Kamynina, Alisa; Vondracek, Petr; Roper, Helen; Longman, Cheryl; Korinthenberg, Rudolf; Marrosu, Gianni; Nurnberg, Peter; Michele, Daniel E.; Plagnol, Vincent; Hurles, Matt; Moore, Steven A.; Sewry, Caroline A.; Campbell, Kevin P.; Voit, Thomas
Muscular dystrophies (MDs) are a heterogeneous group of diseases, caused by mutations in different components of sarcolemma, extracellular matrix, or enzymes. Inflammation and innate or adaptive immune response activation are prominent features of MDs. Various therapies under development are directed toward rescuing the dystrophic muscle damage using gene transfer or cell therapy. Here we discussed current knowledge about involvement of immune system responses to experimental therapies in MDs.
Sitzia, Clementina; Erratico, Silvia; Torrente, Yvan
Only isolated prospective studies have attempted to chart the natural history of facioascapulohumeral muscular dystrophy (FSHD),\\u000a a benign myopathy with notoriously variable clinical manifestations and progression. This 10-year prospective study was performed\\u000a to document by simple clinical methods the natural history of 16 patients with moderately advanced FSHD. Limb strength was\\u000a evaluated by the bedside manual muscle test. Global weakness
Joerg-Patrick StubgenAnnette Stipp; Annette Stipp
Mazindol has been reported to improve muscle function in Duchenne muscular dystrophy (DMD) by virtue of its growth hormone (GH) suppression. The effects were studied on GH secretion (in response to growth hormone releasing factor and sleep) of mazindol 2 mg daily for 3 months in five boys with DMD. No consistent change was found following mazindol therapy. Adverse effects were noted in all the boys which may preclude long term use of mazindol in DMD.
Coakley, J H; Moorcraft, J; Hipkin, L J; Smith, C S; Griffiths, R D; Edwards, R H
The association of epidermolysis bullosa simplex and muscular dystrophy (EBS-MD) has rarely been discussed in ophthalmology literature. This case report offers a brief summary of epidermolysis bullosa and describes what is known about EBS-MD. The case involves a patient with EBS-MD who presented with ptosis and ophthalmoplegia, suggesting that these may be complications of EBS-MD. PMID:20829732
Auringer, David E; Simon, John W; Meyer, Dale R; Malone, Anthony
Epidermolysis bullosa associated with muscular dystrophy is a rare, autosomal recessive form of epidermolysis bullosa simplex caused by mutations in the plectin gene, PLEC1. We describe a phenotypically mild case due to compound heterozygous mutations in PLEC1 (2677_2685del and the novel mutation Q1644X). Clinical features included mild skin blistering since birth, slowly progressive and late-onset upper limb-predominant weakness, facial weakness, ptosis, incomplete ophthalmoplegia, and paroxysmal atrial fibrillation. PMID:21674528
Yiu, Eppie M; Klausegger, Alfred; Waddell, Leigh B; Grasern, Nikolaus; Lloyd, Lyn; Tran, Kim; North, Kathryn N; Bauer, Johann W; McKelvie, Penelope; Chow, C W; Ryan, Monique M; Murrell, Dedee F
As blood cells such as platelets, lymphocytes and erythrocytes from patients with Duchenne muscular dystrophy show evidence of membrane alterations and elevation of intra-cellular calcium, one of the calcium related changes i.e., the activity of calcium activated neutral protease (CANP) was monitored and found to be elevated in erythrocytes, lymphocytes and platelets. As similar changes were observed in platelets of carriers of this disease, CANP in platelets may serve as a useful index for carrier detection. PMID:2347611
Moses, L; Shailaja, B; Anandaraj, M P
Facioscapulohumeral muscular dystrophy (FSHD) is an inherited disease, and although strongly suggested, a contribution of\\u000a inflammation to its pathogenesis has never been demonstrated. In FSHD patients, we found by immunohistochemistry inflammatory\\u000a infiltrates mainly composed by CD8+ T cells in muscles showing hyperintensity features on T2-weighted short tau inversion recovery magnetic resonance imaging\\u000a (T2-STIR-MRI) sequences. Therefore, we evaluated the presence of
Giovanni Frisullo; Roberto Frusciante; Viviana Nociti; Giorgio Tasca; Rosaria Renna; Raffaele Iorio; Agata Katia Patanella; Elisabetta Iannaccone; Alessandro Marti; Monica Rossi; Assunta Bianco; Mauro Monforte; Pietro Attilio Tonali; Massimiliano Mirabella; Anna Paola Batocchi; Enzo Ricci
The results obtained in this study demonstrated that experimentally induced alimentary muscular dystrophy (MD) in Cobb 500\\u000a broiler chickens resulted in increased plasma concentrations of malondialdehyde (MDA), deviations in activities of erythrocyte\\u000a antioxidant enzymes Cu,Zn-SOD (decrease), and CAT (increase) as well as reduction in plasma concentrations of trace elements\\u000a Cu, Zn, and Se in affected birds. These data evidenced the
Nedyalka V. Georgieva; Krasimir Stoyanchev; Nadia Bozakova; Ivanka Jotova
Patients with Duchenne muscular dystrophy (DMD) are at high risk of perioperative complications. DMD may be accompanied by heart failure resulting from dystrophic involvement of the myocardium, which can be subclinical in the early stages of the disease. This case demonstrates that a normal preoperative ECG and echocardiograph cannot exclude the development of heart failure during anaesthesia in DMD patients undergoing major surgery. PMID:12765898
Schmidt, G N; Burmeister, M-A; Lilje, C; Wappler, F; Bischoff, P
Neuromuscular disorders (NMD) are chronic devastating diseases. The aim of this multicenter cross-sectional study was to evaluate\\u000a the socioeconomic impact of three NMDs in Germany. Patients (n = 107) with amyotrophic lateral sclerosis (ALS), myasthenia gravis (MG) or facioscapulohumeral muscular dystrophy (FSHD)\\u000a were recruited consecutively in seven centers in Germany. The health-economic data were collected using a “bottom-up” approach\\u000a consisting of comprehensive
Karsten Schepelmann; Yaroslav Winter; Annika E. Spottke; Detlef Claus; Christoph Grothe; Rolf Schröder; Dieter Heuss; Stefan Vielhaber; Veit Mylius; Reinhard Kiefer; Bertold Schrank; Wolfgang H. Oertel; Richard Dodel
Background Congenital muscular dystrophy (CMD), among the myopathic disorders is one form of flaccid neuromuscular disorder (NMD). Patients\\u000a with NMD frequently develop progressive spinal deformity. For NMD patients who have a severe spinal deformity, sitting is\\u000a often difficult and is accompanied by pain and breakdown of the skin. Spinal deformity surgery in these patients has been\\u000a highly effective in stabilizing the
Masashi Takaso; Toshiyuki Nakazawa; Takayuki Imura; Takamitsu Okada; Masaki Ueno; Wataru Saito; Kazuhisa Takahashi; Masashi Yamazaki; Seiji Ohtori
Emerin is a nuclear envelope protein whose biological function remains to be elucidated. Mutations of emerin gene cause the Emery-Dreifuss muscular dystrophy, a neuromuscular disorder also linked to mutations of lamin A\\/C. In this paper, we analyze the interaction between emerin and actin in differentiating mouse myoblasts. We demonstrate that emerin and lamin A\\/C are bound to actin at the
Giovanna Lattanzi; Vittoria Cenni; Sandra Marmiroli; Cristina Capanni; Elisabetta Mattioli; Luciano Merlini; Stefano Squarzoni; Nadir Mario Maraldi
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy.
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy. PMID:22691392
Benedetti, Sara; Bernasconi, Pia; Bertini, Enrico; Biagini, Elena; Boriani, Giuseppe; Capanni, Cristina; Carboni, Nicola; Cenacchi, Giovanna; Columbaro, Marta; D'Adamo, Monica; D'Amico, Adele; D'Apice, Maria Rosaria; Fontana, Marianna; Gambineri, Alessandra; Lattanzi, Giovanna; Liguori, Rocco; Maraldi, Nadir M; Mazzanti, Laura; Mercuri, Eugenio; Mongini, Tiziana; Morandi, Lucia O; Neri, Iria; Nigro, Giovanni; Novelli, Giuseppe; Ortolani, Michela; Pasquali, Renato; Pini, Antonella; Petrini, Stefania; Politano, Luisa; Previtali, Stefano; Pucci, Lisa; Rapezzi, Claudio; Ricci, Giulia; Rodolico, Carmelo; Sbraccia, Paolo; Scarano, Emanuela; Siciliano, Gabriele; Squarzoni, Stefano; Toscano, Antonio; Vercelli, Liliana; Ziacchi, Matteo
Scapuloperoneal muscular dystrophy is a group of genetically heterogeneous disorders that share the phenotype of progressive weakness of scapular and anterior distal leg muscles. Recessive mutations in C-terminal domains of TRIM32 result in limb-girdle muscular dystrophy 2H and sarcotubular myopathy, a rare congenital myopathy commonly seen in Hutterites. A scapuloperoneal phenotype has never been reported in sarcotubular myopathy. We here report a 23-year-old Hutterite man with a one-year history of progressive weakness predominantly involving the anterior tibial and left scapular muscles, and hyperCKemia. Biopsy of the anterior tibial muscle showed an active myopathy with non-rimmed vacuoles and mild denervation atrophy associated with reinnervation. The vacuoles are similar to those described in sarcotubular myopathy. TRIM32 sequencing revealed the common c.1459G>A mutation at homozygosity. A search for mutations in TRIM32 should be considered in patients with scapuloperoneal muscular dystrophy, and especially in patients of Hutterite origin or with an atypical vacuolar myopathy. PMID:23142638
Liewluck, Teerin; Tracy, Jennifer A; Sorenson, Eric J; Engel, Andrew G
Since most centers in developing countries have limited facilities for investigation of patients with muscular dystrophies and similar disorders, this study was conducted with the aim of assessing the correlation between clinical, electromyographic (EMG) and histopathological findings in this group. We included 100 patients with muscular dystrophy and clinically similar disorders and subjected them to detailed clinical, electrophysiological and histopathological as well as immunohistochemical evaluation. Sensitivity, specificity, positive and negative predictive values and concordance rates for clinical and EMG diagnosis compared to diagnosis after histopathological examination were analyzed. With histopathology as standard, clinical diagnosis and a concordant EMG have very high sensitivity and negative predictive value (100%), but low specificity (33.3%). We conclude that detailed histopathological evaluation with immunohistochemical analysis is essential for the work-up of patients with suspected muscular dystrophies, since occasionally treatable muscle disorders like inflammatory myopathies can be detected when not suspected clinically. Muscle biopsies should only be conducted at major centers where full histochemical facilities are available. PMID:15337133
Shukla, Garima; Bhatia, Manvir; Sarkar, Chitra; Padma, M V; Tripathi, Manjari; Jain, Satish
Much progress has been made over the past decade elucidating the molecular basis for a variety of muscular dystrophies (MD’s). Accordingly, there are examples of mouse models of MD whose disease progression has been halted in large part with the use of viral vector technology. Even so, we must acknowledge significant limitations of present vector systems that must be overcome prior to successful treatment of humans with such approaches. This review will present a variety of viral-mediated therapeutic strategies aimed at counteracting the muscle-wasting symptoms associated with muscular dystrophy. We include viral vector systems used for muscle gene transfer, with a particular emphasis on adeno-associated virus. Findings of several encouraging studies focusing on repair of the mutant dystrophin gene are also included. Lastly, we present a discussion of muscle compensatory therapeutics being considered that include pathways involved in the up-regulation of utrophin, promotion of cellular adhesion, enhancement of muscle mass, and antagonism of the inflammatory response. Considering the complexity of the muscular dystrophies, it appears likely that a multilayered approach tailored to a patient sub-group may be warranted in order to effectively contest the progression of this devastating disease.
Odom, Guy L.; Gregorevic, Paul; Chamberlain, Jeffrey S.
Despite the recent progress in the broad-scaled analysis of proteins in body fluids, there is still a lack in protein profiling approaches for biomarkers of rare diseases. Scarcity of samples is the main obstacle hindering attempts to apply discovery driven protein profiling in rare diseases. We addressed this challenge by combining samples collected within the BIO-NMD consortium from four geographically dispersed clinical sites to identify protein markers associated with muscular dystrophy using an antibody bead array platform with 384 antibodies. Based on concordance in statistical significance and confirmatory results obtained from analysis of both serum and plasma, we identified eleven proteins associated with muscular dystrophy, among which four proteins were elevated in blood from muscular dystrophy patients: carbonic anhydrase III (CA3) and myosin light chain 3 (MYL3), both specifically expressed in slow-twitch muscle fibers and mitochondrial malate dehydrogenase 2 (MDH2) and electron transfer flavoprotein A (ETFA). Using age-matched sub-cohorts, 9 protein profiles correlating with disease progression and severity were identified, which hold promise for the development of new clinical tools for management of dystrophinopathies. PMID:24920607
Ayoglu, Burcu; Chaouch, Amina; Lochmüller, Hanns; Politano, Luisa; Bertini, Enrico; Spitali, Pietro; Hiller, Monika; Niks, Eric H; Gualandi, Francesca; Pontén, Fredrik; Bushby, Kate; Aartsma-Rus, Annemieke; Schwartz, Elena; Le Priol, Yannick; Straub, Volker; Uhlén, Mathias; Cirak, Sebahattin; 't Hoen, Peter A C; Muntoni, Francesco; Ferlini, Alessandra; Schwenk, Jochen M; Nilsson, Peter; Al-Khalili Szigyarto, Cristina
Recent studies have identified a number of forms of muscular dystrophy, termed dystroglycanopathies, which are associated with loss of natively glycosylated ?–dystroglycan. Here we identify a new animal model for this class of disorders in Sphynx and Devon Rex cats. Affected cats displayed a slowly progressive myopathy with clinical and histologic hallmarks of muscular dystrophy including skeletal muscle weakness with no involvement of peripheral nerves or CNS. Skeletal muscles had myopathic features and reduced expression of ?–dystroglycan, while ?–dystroglycan, sarcoglycans, and dystrophin were expressed at normal levels. In the Sphynx cat, analysis of laminin and lectin binding capacity demonstrated no loss in overall glycosylation or ligand binding for the ?-dystroglycan protein, only a loss of protein expression. A reduction in laminin-?2 expression in the basal lamina surrounding skeletal myofibers was also observed. Sequence analysis of translated regions of the feline dystroglycan gene (DAG1) in affected cats did not identify a causative mutation, and levels of DAG1 mRNA determined by real-time QRT-PCR did not differ significantly from normal controls. Reduction in the levels of glycosylated ?–dystroglycan by immunoblot was also identified in an affected Devon Rex cat. These data suggest that muscular dystrophy in Sphynx and Devon Rex cats results from a deficiency in ?-dystroglycan protein expression, and as such may represent a new type of dystroglycanopathy where expression, but not glycosylation, is affected.
Martin, Paul T; Diane Shelton, G.; Dickinson, Peter J; Sturges, Beverly K; Xu, Rui; LeCouteur, Richard A; Guo, Ling T; Grahn, Robert A; Lo, Harriet P; North, Kathryn N; Malik, Richard; Engvall, Eva; Lyons, Leslie A
Serum levels of B-type natriuretic peptide have moderate utility for detection of early ventricular dysfunction in adults and in experimental muscular dystrophy. To determine if B-type natriuretic peptide levels are useful in the detection of early left ventricular dysfunction in Duchenne muscular dystrophy patients, measurements were obtained in 21 patients being evaluated by echocardiography for left ventricular dysfunction. Two patients with clinical evidence of heart failure were excluded (mean B-type natriuretic peptide level of 352 pg/ml). Age range of the remaining 19 patients was 9-21 yrs. Fractional shortening was abnormal (<30%) in 14/19 and early diastolic tissue Doppler velocities were abnormal in 13/16. In these patients B-type natriuretic peptide levels were clearly normal (<30 pg/ml) in 15/19 and only mildly elevated (30-80 pg/ml) in 4/19. The 4 patients with mildly elevated B-type natriuretic peptide had significantly lower fractional shortening (12.6+/-5.9 versus 19.8+/-5.3, p<0.05). In conclusion, B-type natriuretic peptide levels are normal in the majority of Duchenne muscular dystrophy patients with asymptomatic left ventricular dysfunction and only mildly elevated when fractional shortening is markedly reduced. PMID:17079036
Mohyuddin, Tayyab; Jacobs, Irwin B; Bahler, Robert C
Duchenne muscular dystrophy in boys progresses rapidly to severe impairment of muscle function and death in the second or third decade of life. Current supportive therapy with corticosteroids results in a modest increase in strength as a consequence of a general reduction in inflammation, albeit with potential untoward long-term side effects and ultimate failure of the agent to maintain strength. Here, we demonstrate that alternative approaches that rescue defective autophagy in mdx mice, a model of Duchenne muscular dystrophy, with the use of rapamycin-loaded nanoparticles induce a reproducible increase in both skeletal muscle strength and cardiac contractile performance that is not achievable with conventional oral rapamycin, even in pharmacological doses. This increase in physical performance occurs in both young and adult mice, and, surprisingly, even in aged wild-type mice, which sets the stage for consideration of systemic therapies to facilitate improved cell function by autophagic disposal of toxic byproducts of cell death and regeneration.-Bibee, K. P., Cheng, Y.-J., Ching, J. K., Marsh, J. N., Li, A. J., Keeling, R. M., Connolly, A. M., Golumbek, P. T., Myerson, J. W., Hu, G., Chen, J., Shannon, W. D., Lanza, G. M., Weihl, C. C., Wickline, S. A. Rapamycin nanoparticles target defective autophagy in muscular dystrophy to enhance both strength and cardiac function. PMID:24500923
Bibee, Kristin P; Cheng, Ya-Jian; Ching, James K; Marsh, Jon N; Li, Allison J; Keeling, Richard M; Connolly, Anne M; Golumbek, Paul T; Myerson, Jacob W; Hu, Grace; Chen, Junjie; Shannon, William D; Lanza, Gregory M; Weihl, Conrad C; Wickline, Samuel A
Recent studies in patients with muscular dystrophies suggest positive effects of aerobic and strength training. These studies focused training on using bicycle ergometers and conventional strength training, which precludes more severely affected patients from participating, because of their weakness. We investigated the functional effects of combined aerobic and strength training in patients with Becker and limb-girdle muscular dystrophies with knee muscle strength levels as low as 3% of normal strength. Eight patients performed 10weeks of aerobic and strength training on an anti-gravity treadmill, which offered weight support up to 80% of their body weight. Six minute walking distance, dynamic postural balance, and plasma creatine kinase were assessed 10weeks prior to training, immediately before training and after 10weeks of training. Training elicited an improvement of walking distance by 8±2% and dynamic postural balance by 13±4%, indicating an improved physical function. Plasma creatine kinase remained unchanged. These results provide evidence that a combination of aerobic and strength training during anti-gravity has the potential to safely improve functional ability in severely affected patients with Becker and limb-girdle muscular dystrophies. PMID:24684860
Berthelsen, Martin Peter; Husu, Edith; Christensen, Sofie Bouschinger; Prahm, Kira Philipsen; Vissing, John; Jensen, Bente Rona
Titin (also called connectin) acts as a scaffold for signaling proteins in muscle and is responsible for establishing and maintaining the structure and elasticity of sarcomeres in striated muscle. Several human muscular dystrophies and cardiomyopathies have previously been linked to mutations in the titin gene. This study reports linkage of the runzel homozygous lethal muscular dystrophy in the zebrafish Danio rerio to a genomic interval containing the titin gene. Analysis of the genomic sequence suggests that zebrafish contain two adjacent titin loci. One titin locus lies within the genetic linkage interval and its expression is significantly reduced in runzel mutants by both immunofluorescence and protein electrophoresis. Morpholino downregulation of this same titin locus in wild-type embryos results in decreased muscle organization and mobility, phenocopying runzel mutants. Additional protein analysis demonstrates that, in wild-type zebrafish, titin isoform sizes are rapidly altered during the development of striated muscle, likely requiring a previously unrecognized need for vertebrate sarcomere remodeling to incorporate developmentally regulated titin isoforms. Decreases of affected titin isoforms in runzel mutants during this time correlate with a progressive loss of sarcomeric organization and suggest that the unaffected titin proteins are capable of sarcomerogenesis but not sarcomere maintenance. In addition, microarray analysis of the ruz transcriptome suggests a novel mechanism of dystrophy pathogenesis, involving mild increases in calpain-3 expression and upregulation of heat shock proteins. These studies should lead to a better understanding of titin's role in normal and diseased muscle. PMID:17678642
Steffen, Leta S; Guyon, Jeffrey R; Vogel, Emily D; Howell, Melanie H; Zhou, Yi; Weber, Gerhard J; Zon, Leonard I; Kunkel, Louis M
Abnormalities in phosphoinositide metabolism are an emerging theme in human neurodegenerative disease. Myotubular myopathy is a prototypical disorder of phosphoinositide dysregulation that is characterized by profound muscle pathology and weakness and that is caused by mutations in MTM1, which encodes a phosphatase that targets 3-position phosphoinositides, including phosphatidylinositol 3-phosphate. Although the association between MTM1 and muscle disease has become increasingly clarified, the normal role(s) of phosphatidylinositol 3-phosphate metabolism in muscle development and homeostasis remain poorly understood. To begin to address the function of phosphatidylinositol 3-phosphate in skeletal muscle, we focused on the primary kinase responsible for its production, and created a muscle-specific conditional knockout of the class III phosphatidylinositol 3-kinase, Pik3c3. Muscle-specific deletion of Pik3c3 did not disturb embryogenesis or early postnatal development, but resulted in progressive disease characterized by reduced activity and death by 2 months of age. Histopathological analysis demonstrated changes consistent with a murine muscular dystrophy. Examination for cellular mechanism(s) responsible for the dystrophic phenotype revealed significant alterations in the autophagolysosomal pathway with mislocation of known dystrophy proteins to the lysosomal compartment. In all, we present the first analysis of Pik3c3 in skeletal muscle, and report a novel association between deletion of Pik3c3 and muscular dystrophy. PMID:24726497
Reifler, Aaron; Li, Xingli; Archambeau, Ashley J; McDade, Joel R; Sabha, Nesrin; Michele, Daniel E; Dowling, James J
Neuronal nitric oxide synthase (nNOS) is a component of the dystrophin complex in skeletal muscle. The absence of dystrophin protein in Duchenne muscular dystrophy and in mdx mouse causes a redistribution of nNOS from the plasma membrane to the cytosol in muscle cells. Aberrant nNOS activity in the cytosol can induce free radical oxidation, which is toxic to myofibers. To test the hypothesis that derangements in nNOS disposition mediate muscle damage in Duchenne dystrophy, we bred dystrophin-deficient mdx male mice and female mdx heterozygote mice that lack nNOS. We found that genetic deletion of nNOS does not itself cause detectable pathology and that removal of nNOS does not influence the extent of increased sarcolemmal permeability in dystrophin-deficient mice. Thus, histological analyses of nNOS-dystrophin double mutants show pathological changes similar to the dystrophin mutation alone. Taken together, nNOS defects alone do not produce muscular dystrophy in the mdx model. PMID:9681470
Chao, D S; Silvagno, F; Bredt, D S
Use of idebenone for the preparation of a medicament for the treating of a muscular dystrophy in particular for treating and/or preventing weakness and/or loss of skeletal muscle tissue and/or cardiomyopathy associated with a muscular dystrophy.
Duchenne Muscular Dystrophy (DMD) is the most common X- linked inherited disease, with an incidence of 1 in 3500 male births. This disease is relentlessly progressive and usually fatal by early adulthood. A wide range of mutations in the dystrophin gene have been characterized for DMD, as well as the less severe form, Becker's Muscular Dystrophy. DMD presents gene therapy
Bruce F. Smith; Joseph N. Kornegay
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominantly inherited muscular disorder, which is characterized by weakness of facial, shoulder and hip girdle, humeral, and anterior distal leg muscles. The FSHD gene has been mapped to 4q35 and a deletion of integral copies of a 3.3-kb DNA repeat motif named D4Z4 was known to be the genetic background of the disorder. Although FSHD is the second most common muscular dystrophy in adulthood, there were few reports on the genetically confirmed patients in Korea. Recently, we experienced four Korean patients with clinical features resembling FSHD. In order to confirm the diagnosis, conventional Southern blot (SB) analysis by using double digestion with EcoRI and BlnI and hybridization with p13E-11 probe was performed in three patients and newly developed long polymerase chain reaction (PCR) method was used for one patient because genomic DNA was not enough for conventional SB for this patient. All patients were demonstrated to have shortened D4Z4 repeats that were consistent with FSHD. Therefore, we could confirm the diagnosis of FSHD in four Korean patients and appropriate genetic counseling was done for the patients and their families. It is of note that long-PCR method could be a good alternative for conventional SB when D4Z4 repeats were less than 5. PMID:19119436
Ki, Chang-Seok; Lee, Seung-Tae; Kim, Kyung-Sook; Kim, Jong-Won; Hong, Yoon-Ho; Sung, Jung-Joon; Park, Kyung Seok; Lee, Kwang-Woo
To assess the presence and persistence of muscular edema and increased myoplasmic sodium (Na(+)) concentration in Duchenne muscular dystrophy (DMD). We examined eight DMD patients (mean age 9.5 ± 5.4 years) and eight volunteers (mean age 9.5 ± 3.2 years) with 3-tesla proton ((1)H) and (23)Na density-adapted 3D-radial MR sequences. Seven DMD patients were re-examined about 7 months later without change of therapy. The eighth DMD patient was re-examined after 5 and 11 months under medication with eplerenone. We quantified muscle edema on STIR images with background noise as reference and fatty degeneration on T1-weighted images using subcutaneous fat as reference. Na(+) was quantified by a muscular tissue Na(+) concentration (TSC) sequence employing a reference containing 51.3 mM Na(+) with 5 % agarose. With an inversion-recovery (IR) sequence, we determined mainly the myoplasmic Na(+). The normalized muscular (23)Na IR signal intensity was higher in DMD than in volunteers (n = 8, 0.75 ± 0.07 vs. 0.50 ± 0.05, p < 0.001) and persisted at second measurement (n = 7, 1st 0.75 ± 0.07, 2nd 0.73 ± 0.06, p = 0.50). When compared to volunteers (25.6 ± 2.0 mmol/l), TSC was markedly increased in DMD (38.0 ± 5.9 mmol/l, p < 0.001) and remained constant (n = 7, 1st 37.9 ± 6.4 mmol/l, 2nd 37.0 ± 4.0 mmol/l, p = 0.49). Muscular edema (15.6 ± 3.5 vs. 6.9 ± 0.7, p < 0.001) and fat content (0.48 ± 0.08 vs. 0.38 ± 0.01, p = 0.003) were elevated in DMD when compared to volunteers. This could also be confirmed during follow-up (n = 7, p = 0.91, p = 0.12). Eplerenone slightly improved muscle strength and reduced muscular sodium and edema. The permanent muscular Na(+) overload in all DMD patients is likely osmotically relevant and responsible for the persisting, mainly intracellular muscle edema that may contribute to the progressive muscle degeneration. PMID:22544297
Weber, M-A; Nagel, A M; Wolf, M B; Jurkat-Rott, K; Kauczor, H-U; Semmler, W; Lehmann-Horn, F
The aim of present study was to analyse the motor unit (MU) changes in progressive muscle dystrophy (PMD) and in inflammatory myopathy (IM) and to evaluate eventual neurogenic factors in MU reorganisation. The material consisted of 20 patients with (PMD), 20 patients with (IM) and 20 healthy age-matched volunteers. The shape of concentric needle motor unit potentials (cn MUPs), including their duration, amplitude, area, size index and number of phases, the interference pattern and the amplitude and area of macro MUPs were evaluated. The cn emg data satisfied the classical criteria for myopathy in all examined patients, at least in one of the tested muscles. A decreased amplitude and/or area of macro MUPs, compatible with myopathy, were observed in 32 of the 40 patients. In some cases of chronic IM and PDM the long duration polyphasic potentials were recorded. The size index (SI) value of long polyphasic MUPs was usually decreased or normal. This feature indicated that desynchronisation of "myopathic" MUPs results from a reduced number of muscle fibers and their degeneration and regeneration. The results indicated no difference in MU reorganization between PMD and IM and no evidence of neurogenic factors in MU changes. PMID:11142114
Rowi?ska-Marci?ska, K; Szmidt-Sa?kowska, E; Kope?, A; Wawro, A; Karwa?ska, A
We describe a family with an autosomal dominant, multisystem disorder, consisting of late-onset proximal muscular dystrophy, electrophysiological myotonia, cataracts, late-onset deafness and male hypogonadism. Four patients were available for clinical examinations. Examination of asymptomatic family members revealed another patient with bilateral cataracts but without definite muscle disorder. Five deceased members of the family had proximal muscle weakness, reportedly or confirmed
Bjarne Udd; Ralf Krahe; Carina Wallgren-Pettersson; Björn Falck; Hannu Kalimo
Duchenne muscular dystrophy (DMD), a progressive X-linked neuromuscular disorder, has an estimated worldwide incidence of 1:3500 male births. Currently, there are no curative treatments and the mean age of diagnosis is 5 years. In addition, subsequent pregnancies frequently occur before a diagnosis is made in an index case. An 'opt in' screening programme was introduced in Wales in 1990 with the aim to: reduce the diagnostic delay, permit reproductive choice and allow planning of the care of the affected boy. Newborn bloodspots were collected routinely as part of the Wales newborn screening programme. Specific consent was obtained for this test separately from the other tests. During the 21-year period, 369,780 bloodspot cards were received from male infants, of these 343,170 (92.8%) were screened using a bloodspot creatine kinase (CK) assay following parental consent. A total of 145 cases had a raised CK activity (?250 U/l) and at follow-up, at 6-8 weeks of age, 79 cases had a normal serum CK (false-positive rate 0.023%) and 66 cases had an elevated serum CK. DMD was confirmed in 56 cases by genotyping/muscle biopsy studies, Becker muscular dystrophy in 5 cases and other rarer forms of muscular dystrophy in 5 cases. This long-term study has so far identified 13 false-negative cases. The incidence of DMD in Wales of 1:5136 during this period is lower than that of 1:4046 before commencement of screening in Wales. Screening has reduced the diagnostic delay enabling reproductive choice for parents of affected boys and earlier administration of current therapies. PMID:23340516
Moat, Stuart J; Bradley, Donald M; Salmon, Rachel; Clarke, Angus; Hartley, Louise
Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy caused by mutations in the dystrophin gene. Loss of dystrophin initiates a progressive decline in skeletal muscle integrity and contractile capacity which weakens respiratory muscles including the diaphragm, culminating in respiratory failure, the leading cause of morbidity and mortality in DMD patients. At present, corticosteroid treatment is the primary pharmacological intervention in DMD, but has limited efficacy and adverse side effects. Thus, there is an urgent need for new safe, cost-effective, and rapidly implementable treatments that slow disease progression. One promising new approach is the amplification of nitric oxide–cyclic guanosine monophosphate (NO–cGMP) signalling pathways with phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors serve to amplify NO signalling that is attenuated in many neuromuscular diseases including DMD. We report here that a 14-week treatment of the mdx mouse model of DMD with the PDE5 inhibitor sildenafil (Viagra®, Revatio®) significantly reduced mdx diaphragm muscle weakness without impacting fatigue resistance. In addition to enhancing respiratory muscle contractility, sildenafil also promoted normal extracellular matrix organization. PDE5 inhibition slowed the establishment of mdx diaphragm fibrosis and reduced matrix metalloproteinase-13 (MMP-13) expression. Sildenafil also normalized the expression of the pro-fibrotic (and pro-inflammatory) cytokine tumour necrosis factor ? (TNF?). Sildenafil-treated mdx diaphragms accumulated significantly less Evans Blue tracer dye than untreated controls, which is also indicative of improved diaphragm muscle health. We conclude that sildenafil-mediated PDE5 inhibition significantly reduces diaphragm respiratory muscle dysfunction and pathology in the mdx mouse model of Duchenne muscular dystrophy. This study provides new insights into the therapeutic utility of targeting defects in NO–cGMP signalling with PDE5 inhibitors in dystrophin-deficient muscle.
Percival, Justin M; Whitehead, Nicholas P; Adams, Marvin E; Adamo, Candace M; Beavo, Joseph A; Froehner, Stanley C
The dystroglycanopathies are a novel group of human muscular dystrophies due to mutations in known or putative glycosyltransferase enzymes. They share the common pathological feature of a hypoglycosylated form of alpha-dystroglycan, diminishing its ability to bind extracellular matrix ligands. The LARGE glycosyltransferase is mutated in both the myodystrophy mouse and congenital muscular dystrophy type 1D (MDC1D). We have transfected various cell lines with a variety of LARGE expression constructs in order to characterize their subcellular localization and effect on alpha-dystroglycan glycosylation. Wild-type LARGE co-localized with the Golgi marker GM130 and stimulated the production of highly glycosylated alpha-dystroglycan (hyperglycosylation). MDC1D mutants had no effect on alpha-dystroglycan glycosylation and failed to localize correctly, confirming their pathogenicity. The two predicted catalytic domains of LARGE contain three conserved DxD motifs. Systematically mutating each of these motifs to NNN resulted in the mislocalization of one construct, while all failed to have any effect on alpha-dystroglycan glycosylation. A construct lacking the transmembrane domain also failed to localize at the Golgi apparatus. These results indicate that LARGE needs to both physically interact with alpha-dystroglycan and function as a glycosyltransferase in order to stimulate alpha-dystroglycan hyperglycosylation. We have also cloned and overexpressed a homologue of LARGE, glycosyltransferase-like 1B (GYLTL1B). Like LARGE it localized to the Golgi apparatus and stimulated alpha-dystroglycan hyperglycosylation. These results suggest that GYLTL1B may be a candidate gene for muscular dystrophy and that its overexpression could compensate for the deficiency of both LARGE and other glycosyltransferases. PMID:15661757
Brockington, Martin; Torelli, Silvia; Prandini, Paola; Boito, Chiara; Dolatshad, Nazanin F; Longman, Cheryl; Brown, Susan C; Muntoni, Francesco
Backgrond Muscular dystrophies consist of a number of juvenile and adult forms of complex disorders which generally cause weakness or efficiency defects affecting skeletal muscles or, in some kinds, other types of tissues in all parts of the body are vastly affected. In previous studies, it was observed that along with muscular dystrophy, immune inflammation was caused by inflammatory cells invasion – like T lymphocyte markers (CD8+/CD4+). Inflammatory processes play a major part in muscular fibrosis in muscular dystrophy patients. Additionally, a significant decrease in amounts of two myogenic recovery factors (myogenic differentation 1 [MyoD] and myogenin) in animal models was observed. The drug glatiramer acetate causes anti-inflammatory cytokines to increase and T helper (Th) cells to induce, in an as yet unknown mechanism. MyoD recovery activity in muscular cells justifies using it alongside this drug. Methods In this study, a nanolipodendrosome carrier as a drug delivery system was designed. The purpose of the system was to maximize the delivery and efficiency of the two drug factors, MyoD and myogenin, and introduce them as novel therapeutic agents in muscular dystrophy phenotypic mice. The generation of new muscular cells was analyzed in SW1 mice. Then, immune system changes and probable side effects after injecting the nanodrug formulations were investigated. Results The loaded lipodendrimer nanocarrier with the candidate drug, in comparison with the nandrolone control drug, caused a significant increase in muscular mass, a reduction in CD4+/CD8+ inflammation markers, and no significant toxicity was observed. The results support the hypothesis that the nanolipodendrimer containing the two candidate drugs will probably be an efficient means to ameliorate muscular degeneration, and warrants further investigation.
Afzal, Ehsan; Zakeri, Saba; Keyhanvar, Peyman; Bagheri, Meisam; Mahjoubi, Parvin; Asadian, Mahtab; Omoomi, Nogol; Dehqanian, Mohammad; Ghalandarlaki, Negar; Darvishmohammadi, Tahmineh; Farjadian, Fatemeh; Golvajoee, Mohammad Sadegh; Afzal, Shadi; Ghaffari, Maryam; Cohan, Reza Ahangari; Gravand, Amin; Ardestani, Mehdi Shafiee
Duchenne muscular dystrophy (DMD)—which is caused by mutations in the dystrophin gene—is one of the most severe myopathies. Among therapeutic strategies, exon skipping allows the rescue of dystrophin synthesis through the production of a shorter but functional messenger RNA. Here, we report the identification of a microRNA—miR-31—that represses dystrophin expression by targeting its 3? untranslated region. In human DMD myoblasts treated with exon skipping, we demonstrate that miR-31 inhibition increases dystrophin rescue. These results indicate that interfering with miR-31 activity can provide an ameliorating strategy for those DMD therapies that are aimed at efficiently recovering dystrophin synthesis.
Cacchiarelli, Davide; Incitti, Tania; Martone, Julie; Cesana, Marcella; Cazzella, Valentina; Santini, Tiziana; Sthandier, Olga; Bozzoni, Irene
Duchenne muscular dystrophy (DMD) is among the most common lethal genetic diseases. It has been proposed that genetic counseling and prenatal diagnosis have begun to lower the incidence. We reviewed the records of all patients with confirmed DMD who were born between 1969 and 2008. Statistics Canada data on annual male births in Nova Scotia were obtained for each year.The overall incidence of 1 per 4700 male births remained stable during the 30-year period of the study. Similarly, the age at diagnosis did not change during that time. PMID:20080524
Dooley, Joseph; Gordon, Kevin E; Dodds, Linda; MacSween, Judith
A series of (+)-negamycin 1 analogues were synthesized, and their readthrough-promoting activity was evaluated for nonsense mutations in Duchenne muscular dystrophy (DMD). A structure–activity relationship study indicated that 11b was the most potent drug candidate. Immunohistochemical analyses suggested that treatment with 11b restored dystrophin expression in mdx mice, a DMD mouse model. Furthermore, 11b decreased serum creatine kinase (CK) levels, an indicator of muscle fiber destruction. Most importantly, 11b demonstrated lower toxicity than 1, and thus, it could be a useful candidate for long-term treatment of DMD.
Objective. To describe a biochemical growth hormone (GH) deficiency and to evaluate therapeutic result in a six-year-old male with Becker muscular dystrophy (BMD). Methods. GH peak was evaluated after response to arginine and insulin. Bone age was evaluated according to Greulich and Pyle method. Results. The GH-supplementary therapy was very effective in terms of growth gain. Conclusion. The possibility of a growth hormone deficiency and treatment with GH in patients with BMD cannot be excluded, especially considering the good therapeutic response.
Calcaterra, Valeria; Malvezzi, Annachiara; Toglia, Rossana; Berardinelli, Angela; Bozzola, Elena; Bozzola, Mauro; Larizza, Daniela
In this detailed muscle biopsy study of a patient with molecularly confirmed diagnosis of limb-girdle muscular dystrophy 2I (LGMD2I) we show some new data, that is the presence of altered expression pattern of costamere components as integrin ?7B and integrin ?1D associated with vinculin costameric derangement and basal lamina ultrastructural abnormalities as detachments and discontinuities suggesting that different cellular compartments are involved in LGMD2I and the altered basement membrane-plasmalemma-cytoskeleton binding can underlie muscle degeneration. PMID:23135029
Sabatelli, Patrizia; Pellegrini, Camilla; Faldini, Cesare; Merlini, Luciano
Duchenne's muscular dystrophy (DMD) is the most common and severe form of myopathy. Patients with DMD are more sensitive to sedative, anesthetic, and neuromuscular blocking agents which may result in intraoperative and early postoperative cardiovascular and respiratory complications, as well as prolonged recovery from anesthesia. In this case report, we describe a 25-year-old male patient admitted for cholecystectomy under general anesthesia. We induced our anesthesia by oxygen, propofol, fentanyl, and rocuronium bromide. Maintenance was done by fentanyl, rocuronium bromide, sevoflurane, and O2. We report in this case the safety use of sugammadex to antagonize the neuromuscular block and rapid recovery in such category of patients. PMID:24715988
Wefki Abdelgawwad Shousha, Ahmed Abdelgawwad; Sanfilippo, Maria; Sabba, Antonio; Pinchera, Paolo
We describe monozygotic twins who are either discordant or show extreme variability in the expression of facioscapulohumeral muscular dystrophy (FSHD). One twin was severely incapacitated by FSHD. The asymptomatic twin demonstrated equivocal facial weakness on physical examination, but no difference on quantitative myometry when compared with normal controls. High-resolution cytogenetic analysis showed no chromosomal abnormalities. Five polymorphic 4q35 markers known to be linked to FSHD showed identical RFLP patterns, indicating that submicroscopic chromosomal rearrangement is unlikely. We conclude that this set of twins represents an extreme case of variability in the expression of the FSHD gene. PMID:8094896
Tawil, R; Storvick, D; Feasby, T E; Weiffenbach, B; Griggs, R C
A 20-year-old man with mild myopathy, external ophthalmoparesis, epilepsy, and diffuse white matter hyperintensity in the brain on magnetic resonance imaging had partial merosin deficiency in muscle and absent merosin in the endoneurium. Motor and sensory nerve conduction velocities were slow. Nerve biopsy showed reduction of large myelinated fibers, short internodes, enlarged nodes, excessive variability of myelin thickness, tomacula, and uncompacted myelin, but no evidence of segmental demyelination, naked axons, or onion bulbs. Thus, in congenital muscular dystrophy, merosin expression may be dissociated in different tissues, and the neuropathy is sensory-motor and due to abnormal myelinogenesis. PMID:12661054
Di Muzio, A; De Angelis, M V; Di Fulvio, P; Ratti, A; Pizzuti, A; Stuppia, L; Gambi, D; Uncini, A
Since the initial description in 2010 of anoctamin 5 deficiency as a cause of muscular dystrophy, a handful of papers have described this disease in cases of mixed populations. We report the first large regional study and present data on new aspects of prevalence, muscular and cardiac phenotypic characteristics, and muscle protein expression. All patients in our neuromuscular unit with genetically unclassified, recessive limb girdle muscular dystrophy (LGMD2), Miyoshi-type distal myopathy (MMD) or persistent asymptomatic hyperCK-emia (PACK) were assessed for mutations in the ANO5 gene. Genetically confirmed patients were evaluated with muscular and cardiopulmonary examination. Among 40 unclassified patients (28 LGMD2, 5 MMD, 7 PACK), 20 were homozygous or compound heterozygous for ANO5 mutations, (13 LGMD2, 5 MMD, 2 PACK). Prevalence of ANO5 deficiency in Denmark was estimated at 1:100.000 and ANO5 mutations caused 11 % of our total cohort of LGMD2 cases making it the second most common LGMD2 etiology in Denmark. Eight patients complained of dysphagia and 3 dated symptoms of onset in childhood. Cardiac examinations revealed increased frequency of premature ventricular contractions. Four novel putative pathogenic mutations were discovered. Total prevalence and distribution of phenotypes of ANO5 disease in a representative regional cohort are described for the first time. A high prevalence of ANO5 deficiency was found among patients with unclassified LGMD2 (46 %) and MMD (100 %). The high incidence of reported dysphagia is a new phenotypic feature not previously reported, and cardiac investigations revealed that ANO5-patients may have an increased risk of ventricular arrhythmia. PMID:23670307
Witting, Nanna; Duno, Morten; Petri, Helle; Krag, Thomas; Bundgaard, Henning; Kober, Lars; Vissing, John
The GRMD (Golden retriever muscular dystrophy) dog has been widely used in pre-clinical trials targeting DMD (Duchenne muscular dystrophy), using in many cases a concurrent immune-suppressive treatment. The aim of this study is to assess if such a treatment could have an effect on the disease course of these animals. Seven GRMD dogs were treated with an association of cyclosporine A (immunosuppressive dosage) and prednisolone (2 mg/kg/d) during 7 months, from 2 to 9 months of age. A multi-parametric evaluation was performed during this period which allowed us to demonstrate that this treatment had several significant effects on the disease progression. The gait quality as assessed by 3D-accelerometry was dramatically improved. This was consistent with the evolution of other parameters towards a significant improvement, such as the clinical motor score, the post-tetanic relaxation and the serum CK levels. In contrast the isometric force measurement as well as the histological evaluation argued in favor of a more severe disease progression. In view of the disease modifying effects which have been observed in this study it should be concluded that immunosuppressive treatments should be used with caution when carrying out pre-clinical studies in this canine model of DMD. They also highlight the importance of using a large range of multi-parametric evaluation tools to reliably draw any conclusion from trials involving dystrophin-deficient dogs, which reproduce the complexity of the human disease. PMID:23185260
Barthélémy, Inès; Uriarte, Ane; Drougard, Carole; Unterfinger, Yves; Thibaud, Jean-Laurent; Blot, Stéphane
Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disease caused by mutations in the gene that encodes the protein dystrophin. Approximately 2 of 3 affected boys inherit their mutation from their carrier mother whereupon other female relatives are at risk of carrying the mutation. Female carriers are also at risk of developing cardiomyopathy and regular cardiac screening is recommended. Clinical genetics services offer genetic counselling and carrier tests for consenting relatives of DMD patients known as 'cascade screening'. We retrospectively analysed data from two genetics centres, West of Scotland and South East Thames where the latter centre operated a computer-held DMD register. Over the period, 1971-2008, a total of 843 potential carriers, in 195 West of Scotland families, were tested: 16% of 1st degree relatives and 48% of 2nd degree and more distant relatives were not tested. In South East Thames, a total of 1223 potential carriers in 349 families were tested: 49% of 1st degree and 65% of 2nd degree and more distant relatives were not tested. These data are similar to Becker muscular dystrophy/DMD carrier screening results recently reported from the Netherlands. Retrospective results from three countries indicate that despite efforts to offer extended cascade screening, significant numbers of potential carriers of DMD remain unaware of their reproductive and health risks. PMID:22428906
McGowan, Ruth; Challoner, Benjamin R; Ross, Sarah; Holloway, Susan; Joss, Shelagh; Wilcox, Douglas; Holden, Simon T; Tolmie, John; Longman, Cheryl
Duchenne and Becker muscular dystrophies (DMD/BMD) are the most common inherited muscle diseases caused by mutations in the dystrophin gene. The reading frame rule explains the genotype-phenotype relationship in DMD/BMD. In Vietnam, extensive mutation analysis has never been conducted in DMD/BMD. Here, 152 Vietnamese muscular dystrophy patients were examined for dystrophin exon deletion by amplifying 19 deletion-prone exons and deletion ends were confirmed by dystrophin cDNA analysis if necessary. The result was that 82 (54%) patients were found to have exon deletions, thus confirming exact deletion ends. A further result was that 37 patterns of deletion were classified. Deletions of exons 45-50 and 49-52 were the most common patterns identified, numbering six cases each (7.3%). The reading frame rule explained the genotype-phenotype relationship, but not five (6.1%) DMD cases. Each of five patients had deletions of exons 11-27 in common. The applicability of the therapy producing semifunctional in frame mRNA in DMD by inducing skipping of a single exon was examined. Induction of exon 51 skipping was ranked at top priority, since 16 (27%) patients were predicted to have semifunctional mRNA skipping. Exons 45 and 53 were the next ranked, with 12 (20%) and 11 (18%) patients, respectively. The largest deletion database of the dystrophin gene, established in Vietnamese DMD/BMD patients, disclosed a strong indication for exon-skipping therapy. PMID:24099565
Tran, Van Khanh; Ta, Van Thanh; Vu, Dung Chi; Nguyen, Suong Thi-Bang; Do, Hai Ngoc; Ta, Minh Hieu; Tran, Thinh Huy; Matsuo, Masafumi
Partial gene deletion is the major cause of mutation leading to Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Partial gene duplication has also been recognized in a few cases. We have conducted a survey for duplication in 72 unrelated nondeletion patients, analyzed by Southern blot hybridization with clones representing the entire DMD cDNA. With careful quantitative analysis of hybridization band intensity, 10 cases were found to carry a duplication of part of the gene, a frequency of 14% for nondeletion cases (10/72), or 6% for all cases (10/181). The extent of these duplications has been characterized according to the published exon-containing HindIII fragment map, and in six of the 10 duplications a novel restriction fragment that spanned the duplication junction was detected. The resulting translational reading frame of mRNA has been predicted for nine duplications. A shift of the reading frame was predicted in four of the six DMD cases and in one of the two intermediate cases, while the reading frame remained uninterrupted in both BMD cases. RFLP and quantitative Southern blot analyses revealed a grandpaternal origin of duplication in four families and grandmaternal origin in one family. In all five families, the duplication was found to originate from a single X chromosome. Unequal sister-chromatid exchange is proposed to be the mechanism for the formation of these duplications. Images p686-a Figure 4 Figure 5
Hu, X Y; Ray, P N; Murphy, E G; Thompson, M W; Worton, R G
We recently identified mutations in the fukutin related protein (FKRP) gene in patients with congenital muscular dystrophy type 1C (MDC1C) and limb girdle muscular dystrophy type 2I (LGMD2I). The sarcolemma of these patients typically displays an immunocytochemical reduction of ?-dystroglycan. In this report we extend these observations and report a clear correlation between the residual expression of ?-dystroglycan and the phenotype. Three broad categories were identified. Patients at the severe end of the clinical spectrum (MDC1C) were compound heterozygote between a null allele and a missense mutation or carried two missense mutations and displayed a profound depletion of ?-dystroglycan. Patients with LGMD with a Duchenne-like severity typically had a moderate reduction in ?-dystroglycan and were compound heterozygotes between a common C826A (Leu276Ileu) FKRP mutation and either a missense or a nonsense mutation. Individuals with the milder form of LGMD2I were almost invariably homozygous for the Leu276Ile FKRP mutation and showed a variable but subtle alteration in ?-dystroglycan immunolabeling. Our data therefore suggest a correlation between a reduction in ?-dystroglycan, the mutation and the clinical phenotype in MDC1C and LGMD2I which supports the hypothesis that dystroglycan plays a central role in the pathogenesis of these disorders.
Brown, Susan C.; Torelli, Silvia; Brockington, Martin; Yuva, Yeliz; Jimenez, Cecilia; Feng, Lucy; Anderson, Louise; Ugo, Isabella; Kroger, Stephan; Bushby, Kate; Voit, Thomas; Sewry, Caroline; Muntoni, Francesco
Duchenne muscular dystrophy (DMD), the most common inherited muscular dystrophy of childhood, leads to death due to cardiorespiratory failure. Paradoxically, mdx mice with the same genetic deficiency of dystrophin exhibit minimal cardiac dysfunction, impeding the development of therapies. We postulated that the difference between mdx and DMD might result from differences in telomere lengths in mice and humans. We show here that, like DMD patients, mice that lack dystrophin and have shortened telomeres (mdx/mTR(KO)) develop severe functional cardiac deficits including ventricular dilation, contractile and conductance dysfunction, and accelerated mortality. These cardiac defects are accompanied by telomere erosion, mitochondrial fragmentation and increased oxidative stress. Treatment with antioxidants significantly retards the onset of cardiac dysfunction and death of mdx/mTR(KO) mice. In corroboration, all four of the DMD patients analysed had 45% shorter telomeres in their cardiomyocytes relative to age- and sex-matched controls. We propose that the demands of contraction in the absence of dystrophin coupled with increased oxidative stress conspire to accelerate telomere erosion culminating in cardiac failure and death. These findings provide strong support for a link between telomere length and dystrophin deficiency in the etiology of dilated cardiomyopathy in DMD and suggest preventive interventions. PMID:23831727
Mourkioti, Foteini; Kustan, Jackie; Kraft, Peggy; Day, John W; Zhao, Ming-Ming; Kost-Alimova, Maria; Protopopov, Alexei; DePinho, Ronald A; Bernstein, Daniel; Meeker, Alan K; Blau, Helen M
Protein-o-mannosyl transferase 1 (POMT1) is a glycosyltransferase involved in ?-dystroglycan (?-DG) glycosylation. Clinical phenotype in POMT1-mutated patients ranges from congenital muscular dystrophy (CMD) with structural brain abnormalities, to limb-girdle muscular dystrophy (LGMD) with microcephaly and mental retardation, to mild LGMD. No cardiac involvement has until now been reported in POMT1-mutated patients. We report three patients who harbored compound heterozygous POMT1 mutations and showed left ventricular (LV) dilation and/or decrease in myocardial contractile force: two had a LGMD phenotype with a normal or close-to-normal cognitive profile and one had CMD with mental retardation and normal brain MRI. Reduced or absent ?-DG immunolabeling in muscle biopsies were identified in all three patients. Bioinformatic tools were used to study the potential effect of POMT1-detected mutations. All the detected POMT1 mutations were predicted in silico to interfere with protein folding and/or glycosyltransferase function. The report on the patients described here has widened the clinical spectrum associated with POMT1 mutations to include cardiomyopathy. The functional impact of known and novel POMT1 mutations was predicted with a bioinformatics approach, and results were compared with previous in vitro studies of protein-o-mannosylase function.
Bello, Luca; Melacini, Paola; Pezzani, Raffaele; D'Amico, Adele; Piva, Luisa; Leonardi, Emanuela; Torella, Annalaura; Soraru, Gianni; Palmieri, Arianna; Smaniotto, Gessica; Gavassini, Bruno F; Vianello, Andrea; Nigro, Vincenzo; Bertini, Enrico; Angelini, Corrado; Tosatto, Silvio C E; Pegoraro, Elena
Electrical impedance myography (EIM) provides a non-invasive approach for quantifying the severity of neuromuscular disease. Here we determine how well EIM data correlates to functional and ultrasound (US) measures of disease in children with Duchenne muscular dystrophy (DMD) and healthy subjects. Thirteen healthy boys, aged 2-12 years and 14 boys with DMD aged 4-12 years underwent both EIM and US measurements of deltoid, biceps, wrist flexors, quadriceps, tibialis anterior, and medial gastrocnemius. EIM measurements were performed with a custom-designed probe using a commercial multifrequency bioimpedance device. US luminosity data were quantified using a gray-scale analysis approach. Children also underwent the 6-minute walk test, timed tests and strength measurements. EIM and US data were combined across muscles. EIM 50 kHz phase was able to discriminate DMD children from healthy subjects with 98% accuracy. In the DMD patients, average EIM phase measurements also correlated well with standard functional measures. For example the 50 kHz phase correlated with the Northstar Ambulatory Assessment test (R = 0.83, p = 0.02). EIM 50 kHz phase and US correlated as well, with R = -0.79 (p < 0.001). These results show that EIM provides valuable objective measures Duchenne muscular dystrophy severity.
Rutkove, S. B.; Darras, B. T.
Duchenne muscular dystrophy (DMD) is an X-linked lethal muscle disorder caused by mutations in the Dmd gene encoding Dystrophin12. DMD model animals, such as mdx mice and canine X-linked muscular dystrophy dogs, have been widely utilized in the development of a treatment for DMD3. Here, we demonstrate the generation of Dmd-mutated rats using a clustered interspaced short palindromic repeats (CRISPR)/Cas system, an RNA-based genome engineering technique that is also adaptive to rats. We simultaneously targeted two exons in the rat Dmd gene, which resulted in the absence of Dystrophin expression in the F0 generation. Dmd-mutated rats exhibited a decline in muscle strength, and the emergence of degenerative/regenerative phenotypes in the skeletal muscle, heart, and diaphragm. These mutations were heritable by the next generation, and F1 male rats exhibited similar phenotypes in their skeletal muscles. These model rats should prove to be useful for developing therapeutic methods to treat DMD.
Nakamura, Katsuyuki; Fujii, Wataru; Tsuboi, Masaya; Tanihata, Jun; Teramoto, Naomi; Takeuchi, Shiho; Naito, Kunihiko; Yamanouchi, Keitaro; Nishihara, Masugi
Duchenne muscular dystrophy (DMD) is a devastating disease that dramatically decreases the lifespan and abilities of affected young people. The primary molecular cause of the disease is the absence of functional dystrophin protein, which is critical to proper muscle function. Those with DMD vary in disease presentation and dystrophin mutation; the same causal mutation may be associated with drastically different levels of disease severity. Also contributing to this variation are the influences of additional modifying genes and/or changes in functional elements governing such modifiers. This genetic heterogeneity complicates the efficacy of treatment methods and to date medical interventions are limited to treating symptoms. Animal models of DMD have been instrumental in teasing out the intricacies of DMD disease and hold great promise for advancing knowledge of its variable presentation and treatment. This review addresses the utility of comparative genomics in elucidating the complex background behind phenotypic variation in a canine model of DMD, Golden Retriever muscular dystrophy (GRMD). This knowledge can be exploited in the development of improved, more personalized treatments for DMD patients, such as therapies that can be tailor-matched to the disease course and genomic background of individual patients.
Brinkmeyer-Langford, Candice; Kornegay, Joe N.
Duchenne muscular dystrophy (DMD) and its milder allelic variant, Becker muscular dystrophy (BMD), result from mutations of the dystrophin gene and lead to progressive muscle deterioration. Enhanced activation of proteasomal degradation underlies critical steps in the pathogenesis of the DMD/BMD dystrophic process. Previously, we demonstrated that treatment with the proteasome inhibitor MG-132 rescues the cell membrane localization of dystrophin and the dystrophin glycoprotein complex in mdx mice, a natural genetic mouse model of DMD. The current work aims to thoroughly define the therapeutic potential in dystrophinopathies of Velcade, a drug that selectively blocks the ubiquitin-proteasome pathway. Velcade is particularly intriguing since it has been approved for the treatment of multiple myeloma. Therefore, its side effects in humans have been explored. Velcade effects were analyzed through two independent methodological approaches. First, we administered the drug systemically in mdx mice over a 2-week period. In this system, Velcade restores the membrane expression of dystrophin and dystrophin glycoprotein complex members and improves the dystrophic phenotype. In a second approach, we treated with the compound explants from muscle biopsies of DMD or BMD patients. We show that the inhibition of the proteasome pathway up-regulates dystrophin, ?-sarcoglycan, and ?-dystroglycan protein levels in explants from BMD patients, whereas it increases the proteins of the dystrophin glycoprotein complex in DMD cases.
Gazzerro, Elisabetta; Assereto, Stefania; Bonetto, Andrea; Sotgia, Federica; Scarfi, Sonia; Pistorio, Angela; Bonuccelli, Gloria; Cilli, Michele; Bruno, Claudio; Zara, Federico; Lisanti, Michael P.; Minetti, Carlo
Duchenne muscular dystrophy, a fatal degenerative muscle disease, is caused by mutations in the dystrophin gene. Loss of dystrophin in the muscle cell membrane causes muscle fiber necrosis. Previously, loss-of-function mutations in dys-1, the Caenorhabditis elegans dystrophin ortholog, were shown to cause a contractile defect and mild fiber degeneration in striated body wall muscle. Here, we show that loss of dystrophin function in C. elegans results in a shorter lifespan and stochastic, age-dependent muscle-cell death. Reduction of dystrophin function also accelerated age-dependent protein aggregation in muscle cells, suggesting a defect in proteostasis. Both muscle cell death and protein aggregation showed wide variability among the muscle cells. These observations suggest that muscle cell death in dys-1 mutants is greatly influenced by cellular environments. Thus, the manipulation of the cellular environment may provide an opportunity to thwart the cell death initiated by the loss of dystrophin. We found that reduced insulin-like growth factor (IGF) signaling, which rejuvenates the cellular environment to protect cells from a variety of age-dependent pathologies, prevented muscle cell death in the dys-1 mutants in a daf-16-dependent manner. Our study suggests that manipulation of the IGF signaling pathways in muscle cells could be a potent intervention for muscular dystrophy. PMID:24191049
Oh, Kelly Hyunju; Kim, Hongkyun
We have developed a fast and accurate PCR-based linkage and carrier detection protocol for families of Duchenne muscular dystrophy (DMD)/Becker muscular dystrophy (BMD) patients with or without detectable deletions of the dystrophin gene, using fluorescent PCR products analyzed on an automated sequencer. When a deletion is found in the affected male DMD/BMD patient by standard multiplex PCR, fluorescently labeled primers specific for the deleted and nondeleted exon(s) are used to amplify the DNA of at-risk female relatives by using multiplex PCR at low cycle number (20 cycles). The products are then quantitatively analyzed on an automatic sequencer to determine whether they are heterozygous for the deletion and thus are carriers. As a confirmation of the deletion data, and in cases in which a deletion is not found in the proband, fluorescent multiplex PCR linkage is done by using four previously described polymorphic dinucleotide sequences. The four (CA)n repeats are located throughout the dystrophin gene, making the analysis highly informative and accurate. We present the successful application of this protocol in families who proved refractory to more traditional analyses.
Schwartz, L S; Tarleton, J; Popovich, B; Seltzer, W K; Hoffman, E P
The GRMD (Golden retriever muscular dystrophy) dog has been widely used in pre-clinical trials targeting DMD (Duchenne muscular dystrophy), using in many cases a concurrent immune-suppressive treatment. The aim of this study is to assess if such a treatment could have an effect on the disease course of these animals. Seven GRMD dogs were treated with an association of cyclosporine A (immunosuppressive dosage) and prednisolone (2 mg/kg/d) during 7 months, from 2 to 9 months of age. A multi-parametric evaluation was performed during this period which allowed us to demonstrate that this treatment had several significant effects on the disease progression. The gait quality as assessed by 3D-accelerometry was dramatically improved. This was consistent with the evolution of other parameters towards a significant improvement, such as the clinical motor score, the post-tetanic relaxation and the serum CK levels. In contrast the isometric force measurement as well as the histological evaluation argued in favor of a more severe disease progression. In view of the disease modifying effects which have been observed in this study it should be concluded that immunosuppressive treatments should be used with caution when carrying out pre-clinical studies in this canine model of DMD. They also highlight the importance of using a large range of multi-parametric evaluation tools to reliably draw any conclusion from trials involving dystrophin-deficient dogs, which reproduce the complexity of the human disease.
Barthelemy, Ines; Uriarte, Ane; Drougard, Carole; Unterfinger, Yves; Thibaud, Jean-Laurent; Blot, Stephane
Duchenne muscular dystrophy (DMD) is an X-linked lethal muscle disorder caused by mutations in the Dmd gene encoding Dystrophin. DMD model animals, such as mdx mice and canine X-linked muscular dystrophy dogs, have been widely utilized in the development of a treatment for DMD. Here, we demonstrate the generation of Dmd-mutated rats using a clustered interspaced short palindromic repeats (CRISPR)/Cas system, an RNA-based genome engineering technique that is also adaptive to rats. We simultaneously targeted two exons in the rat Dmd gene, which resulted in the absence of Dystrophin expression in the F0 generation. Dmd-mutated rats exhibited a decline in muscle strength, and the emergence of degenerative/regenerative phenotypes in the skeletal muscle, heart, and diaphragm. These mutations were heritable by the next generation, and F1 male rats exhibited similar phenotypes in their skeletal muscles. These model rats should prove to be useful for developing therapeutic methods to treat DMD. PMID:25005781
Nakamura, Katsuyuki; Fujii, Wataru; Tsuboi, Masaya; Tanihata, Jun; Teramoto, Naomi; Takeuchi, Shiho; Naito, Kunihiko; Yamanouchi, Keitaro; Nishihara, Masugi
Objective: To review current approaches for obtaining patient data in Duchenne muscular dystrophy (DMD) and consider how monitoring and comparing outcome measures across DMD clinics could facilitate standardized and improved patient care. Methods: We reviewed annual standardized data from cystic fibrosis (CF) clinics and DMD care guidelines and consensus statements; compared current approaches to obtain DMD patient data and outcome measures; and considered the best method for implementing public reporting of outcomes, to drive improvements in health care delivery. Results: Current methods to monitor DMD patient information (MD STARnet, DuchenneConnect, and TREAT-NMD) do not yet provide patients with comparative outcome data. The CF patient registry allows for reporting of standard outcomes across clinics and is associated with improved CF outcomes. A similar patient registry is under development for the Muscular Dystrophy Association (MDA) clinic network. Suggested metrics for quality care include molecular diagnosis, ambulatory status and age at loss of ambulation, age requiring ventilator support, and survival. Conclusions: CF longevity has increased by almost 33% from 1986 to 2010, in part due to a CF patient registry that has been stratified by individual care centers since 1999, and publically available since 2006. Implementation of outcome reporting for MDA clinics might promote a similar benefit to patients with DMD.
Cwik, Valerie A.; Marshall, Bruce C.; Ciafaloni, Emma; Wolff, Jodi M.; Getchius, Thomas S.; Griggs, Robert C.
Duchenne muscular dystrophy, a fatal degenerative muscle disease, is caused by mutations in the dystrophin gene. Loss of dystrophin in the muscle cell membrane causes muscle fiber necrosis. Previously, loss-of-function mutations in dys-1, the Caenorhabditis elegans dystrophin ortholog, were shown to cause a contractile defect and mild fiber degeneration in striated body wall muscle. Here, we show that loss of dystrophin function in C. elegans results in a shorter lifespan and stochastic, age-dependent muscle-cell death. Reduction of dystrophin function also accelerated age-dependent protein aggregation in muscle cells, suggesting a defect in proteostasis. Both muscle cell death and protein aggregation showed wide variability among the muscle cells. These observations suggest that muscle cell death in dys-1 mutants is greatly influenced by cellular environments. Thus, the manipulation of the cellular environment may provide an opportunity to thwart the cell death initiated by the loss of dystrophin. We found that reduced insulin-like growth factor (IGF) signaling, which rejuvenates the cellular environment to protect cells from a variety of age-dependent pathologies, prevented muscle cell death in the dys-1 mutants in a daf-16–dependent manner. Our study suggests that manipulation of the IGF signaling pathways in muscle cells could be a potent intervention for muscular dystrophy.
Oh, Kelly Hyunju; Kim, Hongkyun
Objective Duchenne Muscular Dystrophy (DMD) displays a clinical range that is not fully explained by the primary DMD mutations. Ltbp4, encoding latent transforming growth factor-? binding protein 4, was previously discovered in a genomewide scan as a modifier of murine muscular dystrophy. We sought to determine whether LTBP4 genotype influenced DMD severity in a large patient cohort. Methods We analyzed nonsynonymous SNPs from human LTBP4 in 254 nonambulatory subjects with known DMD mutations. These SNPs, V194I, T787A, T820A, and T1140M, form “VTTT” and “IAAM” LTBP4 haplotypes. Results Individuals homozygous for the IAAM LTBP4 haplotype remained ambulatory significantly longer than those heterozygous or homozygous for the VTTT haplotype. Glucocorticoid-treated patients who were IAAM homozygotes lost ambulation at 12.5 ± 3.3 years compared to 10.7 ± 2.1 years for treated VTTT heterozygotes or homozygotes. IAAM fibroblasts exposed to TGF? displayed reduced phospho-SMAD signaling compared to VTTT fibroblasts, consistent with LTBP4's role as regulator of TGF?. Interpretation LTBP4 haplotype influences age at loss of ambulation, and should be considered in the management of DMD patients.
Flanigan, Kevin M.; Ceco, Ermelinda; Lamar, Kay-Marie; Kaminoh, Yuuki; Dunn, Diane M.; Mendell, Jerry R.; King, Wendy M.; Pestronk, Alan; Florence, Julaine M.; Mathews, Katherine D.; Finkel, Richard S.; Swoboda, Kathryn J.; Gappmaier, Eduard; Howard, Michael T.; Day, John W.; McDonald, Craig; McNally, Elizabeth M.; Weiss, Robert B.
This study evaluated efficacy and safety of growth hormone treatment in Duchenne muscular dystrophy boys with glucocorticoid-induced growth failure. We reviewed 39 consecutive boys (average age 11.5 years; 32 ambulatory) treated with growth hormone for 1 year during a four-year period. Boys were on long-term daily deflazacort or prednisone (mean duration 5 ± 2.2 years; dosing regimen prednisone 0.75 mg/kg/day equivalent). Primary outcomes were growth velocity and height-for-age z-scores (height SD) at 1 year. Height velocity increased from 1.3 ± 0.2 to 5.2 ± 0.4 cm/year on growth hormone (p<0.0001). Pre-growth hormone decline in height SD (-0.5 ± 0.2SD/year) stabilized at height SD -2.9 ± 0.2 on growth hormone (p<0.0001). The rate of weight gain was unchanged, at 2.8 ± 0.6 kg/year pre-growth hormone and 2.6 ± 0.7 kg/year at 1 year. Motor function decline was similar pre-growth hormone and at 1 year. Cardiopulmonary function was unchanged. Three experienced side effects. In this first comprehensive report of growth hormone in Duchenne muscular dystrophy, growth hormone improved growth at 1 year, without detrimental effects observed on neuromuscular and cardiopulmonary function. PMID:22967789
Rutter, Meilan M; Collins, James; Rose, Susan R; Woo, Jessica G; Sucharew, Heidi; Sawnani, Hemant; Hor, Kan N; Cripe, Linda H; Wong, Brenda L
Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are X-linked recessive neuromuscular diseases caused by dystrophin gene mutations. Deletions, or more rarely duplications, of single or multiple exons within the dystrophin gene can be detected by current molecular methods in approximately 65% of DMD patients. Mothers of affected males have a two-thirds chance of carrying a dystrophin mutation, whilst approximately one-third of affected males have de novo mutations. Currently, Southern blot analysis and multiplex PCR directed against exons in deletion hot spots are used to determine female carrier status. However, both of these assays depend on dosage assessment to accurately identify carriers since, in females, the normal X chromosome is also present. To obviate quantitation of gene dosage, we have developed exon-specific probes from the dystrophin gene and applied them to a screen for potential carrier females using fluorescence in situ hybridization (FISH). Cosmid clones, representing 16 exons, were identified and used in FISH analysis of DMD/BMD families. Our preliminary work has identified multiple, informative probes for several families with dystrophin deletions and has shown that a FISH-based assay can be an effective and direct method for establishing the DMD/BMD carrier status of females. PMID:10854113
Ligon, A H; Kashork, C D; Richards, C S; Shaffer, L G
In Duchenne muscular dystrophy (DMD), dystrophin mutation leads to progressive lethal skeletal muscle degeneration. For unknown reasons, dystrophin deficiency does not recapitulate DMD in mice (mdx), which have mild skeletal muscle defects and potent regenerative capacity. We postulated that human DMD progression is a consequence of loss of functional muscle stem cells (MuSC), and the mild mouse mdx phenotype results from greater MuSC reserve fueled by longer telomeres. We report that mdx mice lacking the RNA component of telomerase (mdx/mTR) have shortened telomeres in muscle cells and severe muscular dystrophy that progressively worsens with age. Muscle wasting severity parallels a decline in MuSC regenerative capacity and is ameliorated histologically by transplantation of wild-type MuSC. These data show that DMD progression results, in part, from a cell-autonomous failure of MuSC to maintain the damage-repair cycle initiated by dystrophin deficiency. The essential role of MuSC function has therapeutic implications for DMD. PMID:21145579
Sacco, Alessandra; Mourkioti, Foteini; Tran, Rose; Choi, Jinkuk; Llewellyn, Michael; Kraft, Peggy; Shkreli, Marina; Delp, Scott; Pomerantz, Jason H; Artandi, Steven E; Blau, Helen M
Female carriers of Duchenne muscular dystrophy (DMD) may demonstrate elevated serum creatine kinase (CK) and reduction of muscle dystrophin in all muscle types. We hypothesized that decreased dystrophin in uterine or pelvic girdle musculature might affect the obstetrical performance of females heterozygous for a dystrophin mutation. We reviewed the outcome of 34 deliveries resulting in 35 children from 13 women who were mothers of males attending a muscular dystrophy clinic. Obstetrical performance was examined retrospectively by chart review and patient contact. Of 35 children, 6 (17%) were delivered in the breech position, which is a fivefold increase above the national standards for term pregnancies. Of the six infants with breech presentation, two were males affected with DMD, one was a female heterozygote, one was a male who died perinatally, and the carrier status of the other two females is unknown. Most DMD affected males (12/14) were delivered in the vertex position. Thus, it is likely that maternal, rather than fetal, muscle weakness was the significant factor in determination of fetal position at term. We speculate that subtle changes in uterine or pelvic girdle muscle tone may contribute to a higher rate of fetal breech position in carriers of the DMD gene. PMID:9415684
Geifman-Holtzman, O; Bernstein, I M; Capeless, E L; Hawley, P; Specht, L A; Bianchi, D W
Summary In Duchenne muscular dystrophy (DMD), dystrophin mutation leads to progressive lethal skeletal muscle degeneration. For unknown reasons, dystrophin deficiency does not recapitulate DMD in mice (mdx), which have mild skeletal muscle defects and potent regenerative capacity. We postulated that human DMD progression is a consequence of loss of functional muscle stem cells (MuSC) and the mild mouse mdx phenotype results from greater MuSC reserve fueled by longer telomeres. We report that mdx mice lacking the RNA component of telomerase (mdx/mTR) have shortened telomeres in muscle cells and severe muscular dystrophy that progressively worsens with age. Muscle wasting severity parallels a decline in MuSC regenerative capacity, and is ameliorated histologically by transplantation of wild-type MuSC. These data show that DMD progression results in part from a cell-autonomous failure of MuSC to maintain the damage-repair cycle initiated by dystrophin deficiency. The essential role of MuSC function has therapeutic implications for DMD.
Sacco, Alessandra; Mourkioti, Foteini; Tran, Rose; Choi, Jinkuk; Llewellyn, Michael; Kraft, Peggy; Shkreli, Marina; Delp, Scott; Pomerantz, Jason H.; Artandi, Steven E.; Blau, Helen M.
PURPOSE—Mutations in the dystrophin gene result in Duchenne muscular dystrophy (DMD). DMD is associated with an abnormal electroretinogram (ERG) if the mutation disrupts the translation of retinal dystrophin (Dp260). Our aim was to determine if incomplete ERG abnormalities would be associated with heterozygous carriers of dystrophin gene mutations.?METHODS—Ganzfeld ERGs were obtained under scotopic and photopic testing conditions from a family which includes the heterozygous maternal grandmother, the heterozygous mother, and her children, two affected boys and dizygotic twin sibs, an unaffected male and heterozygous female. Southern blot analyses were done to characterise the dystrophin mutation.?RESULTS—The dystrophin gene was found to contain a deletion encompassing exon 50. The ERGs in the two affected boys were abnormal, consistent with the DMD ERG phenotype. Serial ERGs of the heterozygous females were abnormal; however, they were less severely affected than the DMD boys. The ERG of the female sib showed a greater abnormality than her mother and maternal grandmother. The unaffected twin had a normal ERG.?CONCLUSIONS—The ERG shows abnormalities associated with carrier status in this family with a single exon deletion. A large study of confirmed obligate carriers is planned to clarify further the value of the ERG in detecting female heterozygous carriers of dystrophin gene mutations.???Keywords: muscular dystrophy; electroretinography; retina; dystrophin
Fitzgerald, K.; Cibis, G.; Gettel, A. H.; Rinaldi, R.; Harris, D.; White, R.
Duchenne muscular dystrophy (DMD) is a devastating disease that dramatically decreases the lifespan and abilities of affected young people. The primary molecular cause of the disease is the absence of functional dystrophin protein, which is critical to proper muscle function. Those with DMD vary in disease presentation and dystrophin mutation; the same causal mutation may be associated with drastically different levels of disease severity. Also contributing to this variation are the influences of additional modifying genes and/or changes in functional elements governing such modifiers. This genetic heterogeneity complicates the efficacy of treatment methods and to date medical interventions are limited to treating symptoms. Animal models of DMD have been instrumental in teasing out the intricacies of DMD disease and hold great promise for advancing knowledge of its variable presentation and treatment. This review addresses the utility of comparative genomics in elucidating the complex background behind phenotypic variation in a canine model of DMD, Golden Retriever muscular dystrophy (GRMD). This knowledge can be exploited in the development of improved, more personalized treatments for DMD patients, such as therapies that can be tailor-matched to the disease course and genomic background of individual patients. PMID:24403852
Brinkmeyer-Langford, Candice; Kornegay, Joe N
Adverse reactions to genral anesthesia, which partly resembled malignant hyperthermia (MH), were more frequent in muscular dystrophy than in controls. In the present study, 35 cases so far reported in Duchenne or Becker muscular dystrophy (DMD or BMD) were analyzed and their pathogenesis was discussed. Cardiac involvements were sole manifestations in 7 cases. In other 28 cases, the acute rhabdomyolysis was the most prevailing manifestation. About 60% of myolysis cases were associated with muscle contracture (rigidity) or other hypermetabolic signs such as hypercapnia, hyperthermia and metabolic acidosis. Cases with BMD were more hyperthermic than with DMD. These results suggest Ca ion-induced hypermetabolic reactions are also present in dystrophinopathy, which have been assumed as core syndromes of the classical (gene-defined) MH. However, question whether the abnormal Ca ion is from the extracellular or intracellular stores is still unclear. Circumstancial evidences suggest that the Ca-induced Ca release (CICR) mechanism might also be involved. Endogenous redox modulators such as nitric oxide or reactive oxygen species in the dystrophic muscle might contribute to the perturbed Ca ion homeostasis. PMID:18326302
Takagi, Akio; Nakase, Hirofumi
The aim of this study was to report results of prophylactic spinal stabilization in patients with Duchenne muscular dystrophy. There is still debate regarding the ideal instrumentation. A prospective study of a consecutive series of 31 patients stabilized with the ISOLA system from D2 to S1 will be presented. The mean follow-up was 22 months (range, 1-60 months). The evaluation of the Cobb angle and pelvic obliquity revealed the following: 1) Cobb angle: preoperation, 48.6 degrees (range, 22-82 degrees); postoperation, 12.5 degrees (range, 0-30 degrees); follow-up, 12.5 degrees (range, 0-42 degrees); and 2) pelvic obliquity: preoperation, 18.2 degrees (range, 3-40 degrees); postoperation, 3.8 degrees (range, 0-13 degrees); follow-up, 5.1 degrees (range, 0-14 degrees). Spinal stabilization with the ISOLA system was found to be a suitable treatment for scoliosis owing to Duchenne muscular dystrophy. It should be carried out after loss of ambulation as soon as a progressive curve of more than 20 degrees is documented. The complication rate was found to be high. PMID:11269806
Heller, K D; Wirtz, D C; Siebert, C H; Forst, R
We assessed the cardiac findings in Duchenne muscular dystrophy (DMD) and Becker-Kiener muscular dystrophy (BMD) patients in the large outpatient group of our single-center institution. The analysis included the revision of patient records (retrospectively) and current echocardiography, electrocardiogram (ECG), and Holter ECG data (prospectively). Reduced left ventricular fraction shortening (FS) < 25% was found in 24% of all patients (50 DMD, 12.1 +/- 4.7 years: 20 BMD, 17.1 +/- 8.5 years). Median age of onset of FS < 25% was 16.8 +/- 1.0 in DMD and 30.4 +/- 3.4 in BMD; (p < 0.05). Holter ECG in DMD demonstrated sinus tachycardia in 26% deprivation of circadian rhythm in 31%, and reduced heart rate variability in 51%. For these reasons, we recommend carrying out echocardiography annually in DMD and BMD > 10 years. Because the rate of disturbances in the cardiac autonomic nervous system is high in DMD, we also recommend Holter ECG annually. Further investigation should be conducted to determine if treatment with ss-blockers and ACE inhibitors in combination reduces cardiac autonomic nervous imbalance, thus improving patient outcome in DMD. PMID:15793655
Kirchmann, C; Kececioglu, D; Korinthenberg, R; Dittrich, S
BACKGROUND: Becker-Kiener muscular dystrophy (BMD) represents an X-linked genetic disease associated with myocardial involvement potentially resulting in dilated cardiomyopathy (DCM). Early diagnosis of cardiac involvement may permit earlier institution of heart failure treatment and extend life span in these patients. Both echocardiography and nuclear imaging methods are capable of detecting later stages of cardiac involvement characterised by wall motion abnormalities.
Ali Yilmaz; Hans-Jürgen Gdynia; Hannibal Baccouche; Heiko Mahrholdt; Gabriel Meinhardt; Cristina Basso; Gaetano Thiene; Anne-Dorte Sperfeld; Albert C Ludolph; Udo Sechtem
Targeted resequencing using next-generation sequencing technology is being rapidly applied to the molecular diagnosis of human genetic diseases. The group of muscular dystrophies may be an appropriate candidate for this approach because these diseases exhibit genotype-phenotype heterogeneity. To perform a proof-of-concept study, we selected four patients with congenital muscular dystrophies with defective glycosylation of alpha-dystroglycan. A custom-solution-based target enrichment kit was designed to capture whole-genic regions of the 26 muscular-dystrophy-related genes, including six genes implicated in alpha-dystroglycanopathies. Although approximately 95% of both coding and noncoding regions were covered with at least 15-read depth, parts of the coding exons of FKRP and POMT2 were insufficiently covered. Homozygous and compound heterozygous POMGnT1 mutations were found in two patients. Two novel noncoding variants of FKTN were identified in one patient who had a retrotransposon insertion mutation of FKTN in only one allele. The current targeted resequencing strategy yielded promising results for the extension of this method to other muscular dystrophies. As suboptimal coverage in a small subset of coding regions may affect the sensitivity of the method, complementary Sanger sequencing may be required. PMID:23453855
Lim, Byung Chan; Lee, Seungbok; Shin, Jong-Yeon; Hwang, Hee; Kim, Ki Joong; Hwang, Yong Seung; Seo, Jeong-Sun; Kim, Jong-Il; Chae, Jong Hee
The developmental expression pattern of four human genes, three of which are involved in progressive muscular dystrophies, was investigated. The rationale for these experiments is that these patterns might provide useful information on the pathophysiology underlying these myopathies. Despite the presence of overlapping clinical signs, the spatiotemporal expression profiles of the corresponding genes differed widely. Transcripts of ?-sarcoglycan(SGCA) were visible
Françoise Fougerousse; Muriel Durand; Laurence Suel; Olivier Pourquié; Anne-Lise Delezoide; Norma B. Romero; Marc Abitbol; Jacques S. Beckmann
Duchenne Muscular Dystrophy (DMD) is a lethal X-linked myopathy occurring in 1 in 3000 male births. The gene, which spans over 2.1 kilobases, has been identified and produces a protein designated dystrophin which is an integral component of the cytoskelet...
M. B. Jackson
We recently described a novel congenital muscular dystrophy (CMD) syndrome characterized by mental retardation, microcephaly, and partial merosin deficiency on muscle biopsy. Linkage analysis excluded involvement of the known CMD loci. We now report on a study performed on the differentiation of cultured myoblasts from one patient affected by this condition to evaluate the potential to form myotubes and merosin
Giovanna Lattanzi; Francesco Muntoni; Patrizia Sabatelli; Stefano Squarzoni; Nadir Mario Maraldi; Vittoria Cenni; Marcello Villanova; Marta Columbaro; Luciano Merlini; Sandra Marmiroli
Muscular dystrophy is a progressive muscle wasting disease that is thought to be initiated by unregulated Ca(2+) influx into myofibers leading to their death. Store-operated Ca(2+) entry (SOCE) through sarcolemmal Ca(2+) selective Orai1 channels in complex with STIM1 in the sarcoplasmic reticulum is one such potential disease mechanism for pathologic Ca(2+) entry. Here, we generated a mouse model of STIM1 overexpression in skeletal muscle to determine whether this type of Ca(2+) entry could induce muscular dystrophy. Myofibers from muscle-specific STIM1 transgenic mice showed a significant increase in SOCE in skeletal muscle, modeling an observed increase in the same current in dystrophic myofibers. Histological and biochemical analysis of STIM1 transgenic mice showed fulminant muscle disease characterized by myofiber necrosis, swollen mitochondria, infiltration of inflammatory cells, enhanced interstitial fibrosis and elevated serum creatine kinase levels. This dystrophic-like disease in STIM1 transgenic mice was abrogated by crossing in a transgene expressing a dominant-negative Orai1 (dnOrai1) mutant. The dnOrai1 transgene also significantly reduced the severity of muscular dystrophy in both mdx (dystrophin mutant mice) and ?-sarcoglycan-deficient (Sgcd(-/-)) mouse models of disease. Hence, Ca(2+) influx across an unstable sarcolemma due to increased activity of a STIM1-Orai1 complex is a disease determinant in muscular dystrophy, and hence, SOCE represents a potential therapeutic target. PMID:24556214
Goonasekera, Sanjeewa A; Davis, Jennifer; Kwong, Jennifer Q; Accornero, Federica; Wei-LaPierre, Lan; Sargent, Michelle A; Dirksen, Robert T; Molkentin, Jeffery D
Congenital muscular dystrophy (CMD) is a clinically and genetically heterogeneous group of inherited muscle disorders. In patients, muscle weakness is usually present at or shortly after birth and is progressive in nature. Merosin deficient congenital muscular dystrophy (MDC1A) is a form of CMD caused by a defect in the laminin-?2 gene (LAMA2). Laminin-?2 is an extracellular matrix protein that interacts with the dystrophin-dystroglycan (DGC) complex in membranes providing stability to muscle fibers. In an N-ethyl-N-nitrosourea mutagenesis screen to develop zebrafish models of neuromuscular diseases, we identified a mutant fish that exhibits severe muscular dystrophy early in development. Genetic mapping identified a splice site mutation in the lama2 gene. This splice site is highly conserved in humans and this mutation results in mis-splicing of RNA and a loss of protein function. Homozygous lama2 mutant zebrafish, designated lama2cl501/cl501, exhibited reduced motor function and progressive degeneration of skeletal muscles and died at 8–15 days post fertilization. The skeletal muscles exhibited damaged myosepta and detachment of myofibers in the affected fish. Laminin-?2 deficiency also resulted in growth defects in the brain and eye of the mutant fish. This laminin-?2 deficient mutant fish represents a novel disease model to develop therapies for modulating splicing defects in congenital muscular dystrophies and to restore the muscle function in human patients with CMD.
Gupta, Vandana A.; Kawahara, Genri; Myers, Jennifer A.; Chen, Aye T.; Hall, Thomas E.; Manzini, M. Chiara; Currie, Peter D.; Zhou, Yi; Zon, Leonard I.; Kunkel, Louis M.; Beggs, Alan H.
Duchenne muscular dystrophy is a devastating neuromuscular disease caused by lack of the protein, dystrophin, in skeletal muscle and heart, although the biochemical mechanism by which dystrophin loss causes muscle dysfunction is unknown. Here we show that the dystrophin-deficient mdx mouse and a mouse lacking both dystrophin and the dystrophin-related protein, utrophin (dko), have abnormal electrocardiograms (ECGs). In skeletal muscle,
Britta L Bia; Paul J Cassidy; Martin E Young; Jill A Rafael; Brendan Leighton; Kay E Davies; George K Radda; Kieran Clarke
Duchenne muscular dystrophy (DMD) is a lethal muscle disorder characterized by mutations in the DMD gene. These mutations primarily disrupt the reading frame, leading to an absence of functional dystrophin protein. Exon-skipping through the use of antisense oligonucleotides has served as a promising therapeutic approach for DMD, and clinical trials in DMD patients are currently underway. Recently, stable and less-toxic
Yoshitsugu Aoki; Tetsuya Nagata; Yuko Shimizu; Shin'ichi Takeda
SUMMARY The cause in sudden postmortem mostly differs in various co- untries in relation to the quality and range of health care sys- tems. We wanted to present a Progressive Muscular Dystrophy case in which we had diagnostic problems. From the death examination and autopsy files, which were sent to Morgue Department of Adana Branch of the Forensic Medicine Council,
Mete K. G; Nursel Gamsiz BÜLGÜN; Behnan ALPER; Ahmet HÜLAL
Background and Objectives In Duchenne and Becker muscular dystrophies, cardiac function deteriorates with time resulting in heart failure which is often fatal. We prospectively evaluated the effect of enalapril and carvedilol on left ventricular (LV) dysfunction in middle childhood and adolescent patients with muscular dystrophy. Subjects and Methods Twenty-three patients with LV dysfunction (22 with Duchenne muscular dystrophy, 1 with Becker muscular dystrophy) were enrolled. We prescribed enalapril (13 patients) or carvedilol (10 patients) randomly from July 2008 to August 2010 and followed up the patients until September 2011. The changes in LV function parameters before and after the treatment were evaluated by echocardiography. Results The mean age at the start of treatment with enalapril or carvedilol was 12.6±3.7 years (median 13 years), and mean follow-up duration was 20.1±8.9 months. In the enalapril group, LV fractional shortening (FS) increased from 25.8±2.1 to 26.6±3.0 (p=0.241). In the carvedilol group, LV FS increased from 26.4±1.1 to 28.6±4.2 (p=0.110). In all 23 patients, LV FS significantly increased from 26.1±1.7 (before) to 27.6±3.7 (after treatment) (p<0.046). Indexed LV dimension at end diastole and LV end-diastolic volume decreased slightly, but without statistical significance by tri-plane volumetry. LV diastolic functional parameters were maintained during follow-up period. Conclusion Enalapril or carvedilol could improve LV systolic function in middle childhood and adolescent patients with muscular dystrophy without significant adverse effects.
Kwon, Hye Won; Kwon, Bo Sang; Kim, Gi Beom; Chae, Jong Hee; Park, June Dong; Bae, Eun Jung
Therapeutic trials in Duchenne Muscular dystrophy (DMD) exclude young boys because traditional outcome measures rely on cooperation. The Bayley-III Scales of Infant and Toddler Development (Bayley-III) have been validated in developing children and those with developmental disorders but have not been studied in DMD. Expanded Hammersmith Functional Motor Scale (HFMSE) and North Star Ambulatory Assessment (NSAA) may also be useful in this young DMD population. Clinical evaluators from the MDA-DMD Clinical Research Network were trained in these assessment tools. Infants and boys with DMD (n=24; 1.9±0.7 years) were assessed. The mean Bayley-III motor composite score was low (82.8 ± 8; p=<.0001)(normal=100 ± 15). Mean gross motor and fine motor function scaled scores were low (both p=<.0001). The mean cognitive comprehensive (p=.0002), receptive language (p=<.0001), and expressive language (p=.0001) were also low compared to normal children. Age was negatively associated with Bayley-III gross motor (r=?0.44 p=.02) but not with fine motor, cognitive, or language scores. HFMSE (n=23) showed a mean score of 31 ± 13. NSAA (n =18 boys; 2.2 ± 0.4years) showed a mean score of 12 ± 5. Outcome assessments of young boys with DMD are feasible and in this multicenter study were best demonstrated using the Bayley-III.
Connolly, Anne M.; Florence, Julaine M.; Cradock, Mary M.; Malkus, Elizabeth C.; Schierbecker, Jeanine R.; Siener, Catherine A.; Wulf, Charlie O.; Anand, Pallavi; Golumbek, Paul T.; Zaidman, Craig M; Miller, J Philip; Lowes, Linda P; Alfano, Lindsay N.; Viollet-Callendret, Laurence; Flanigan, Kevin M.; Mendell, Jerry R.; McDonald, Craig M.; Goude, Erica; Johnson, Linda; Nicorici, Alina; Karachunski, Peter I.; Day, John W.; Dalton, Joline C.; Farber, Janey M.; Buser, Karen K.; Darras, Basil T.; Kang, Peter B.; Riley, Susan O.; Shriber, Elizabeth; Parad, Rebecca; Bushby, Kate; Eagle, Michelle
Changes in pain-related beliefs, coping, and catastrophizing predict changes in pain intensity, pain interference, and psychological functioning in individuals with Myotonic Muscular Dystrophy and Facioscapulohumeral Dystrophy
Objectives The primary aim of this study was to test hypothesized associations between changes in psychological variables (i.e., pain beliefs, catastrophizing and coping strategies) and changes in pain intensity and related adjustment (i.e., pain interference and psychological functioning) in individuals with Myotonic Muscular Dystrophy (MMD) and Facioscapulohumeral Muscular Dystrophy (FSHD). Methods A sample of 107 adults with a diagnosis of MMD or FSHD, reporting pain in the past three months, completed assessments at two time-points, separated by about 24 months. Results Results showed that changes in pain-related psychological variables were significantly associated with changes in psychological functioning, pain intensity and pain interference. Specifically, increases in the belief that emotion influences pain, and catastrophizing were associated with decreases in psychological functioning. Increases in the coping strategies of asking for assistance and resting, and the increases of catastrophizing were associated with increases in pain intensity. Finally, increases in pain intensity and asking for assistance were associated with increases in pain interference. Discussion The results support the utility of the biopsychosocial model of pain for understanding pain and its impact in individuals with MMD or FSHD. These findings may inform the design and implementation of psychosocial pain treatments for people with muscular dystrophy and chronic pain.
Nieto, Ruben; Raichle, Katherine A.; Jensen, Mark P.; Miro, Jordi
The purpose of this study was to determine the age of hand involvement in Duchenne muscular dystrophy (DMD), since various types of hand dynamometry have been applied to evaluate patients in clinical trials. We studied 40 patients with DMD from our university hospital clinic and 80 healthy, age-matched controls. Hand strength was evaluated by handgrip and pinch dynamometries, and by manual testing. Physical disability was measured with a functional scale. Hand weakness was present since early stages in patients with DMD. However, hand strength tended to increase with age in the first decade, although never reaching the control values. Decrease of strength occurred later. Handgrip and pinch dynamometry values were significantly correlated with global hand strength, which were inversely correlated with functional capacity only in the group older than 10 years. Hand dynamometry should be applied with caution as an outcome measure in therapeutical trials in young patients with DMD. PMID:18207403
Mattar, Fabiana Luisa; Sobreira, Claudia
Duchenne muscular dystrophy (DMD)--which is caused by mutations in the dystrophin gene-is one of the most severe myopathies. Among therapeutic strategies, exon skipping allows the rescue of dystrophin synthesis through the production of a shorter but functional messenger RNA. Here, we report the identification of a microRNA--miR-31--that represses dystrophin expression by targeting its 3' untranslated region. In human DMD myoblasts treated with exon skipping, we demonstrate that miR-31 inhibition increases dystrophin rescue. These results indicate that interfering with miR-31 activity can provide an ameliorating strategy for those DMD therapies that are aimed at efficiently recovering dystrophin synthesis. PMID:21212803
Cacchiarelli, Davide; Incitti, Tania; Martone, Julie; Cesana, Marcella; Cazzella, Valentina; Santini, Tiziana; Sthandier, Olga; Bozzoni, Irene
Blood plasma lipids were studied in patients with Duchenne's myodystrophy. The authors examined 40 patients, aged 3-16 years suffering from different stages of Duchenne's muscular dystrophy. Lipids and fractional composition of plasma phospholipids were investigated by thin-layer chromatography on "Silufol" plates; lipoproteins were assessed by the method of high voltage disk electrophoresis in polyacrylamide gel. The changes in plasma lipids were found to be correlated with both the stage of the myodystrophic process and the type of the disease course. The changes included blood plasma lipemia with increased levels of triglycerides, cholesterol and its esters and also a decrease in phospholipid concentrations with the concomitant redistribution of their fractions. A study of the blood plasma lipoprotein spectrum showed a rise in the values of chylomicrons, remnants and alpha-LP. The data obtained are important for objective determination of the disease stage. PMID:6675360
Temin, P A; Islamova, I B
The recent development of therapeutic approaches for Duchenne muscular dystrophy (DMD) has highlighted the need to identify clinical outcome measures for planned efficacy studies. Although several studies have reported the value of functional scales, timed tests, and measures of endurance aimed at ambulant individuals, less has been done to identify reliable measures of function in individuals who have lost ambulation. The aim of this paper is to provide a critical review of the existing literature on functional measures assessing upper extremity function in DMD. Four observer-rated, performance-based measures and four self-reported scales have been previously used in DMD. Each scale provides useful information but none reflects all the different levels of functional ability in activities of daily living observed in individuals with DMD at different ages. PMID:22713125
Mazzone, Elena S; Vasco, Gessica; Palermo, Concetta; Bianco, Flaviana; Galluccio, Carmen; Ricotti, Valeria; Castronovo, Antonella D; Mauro, Maria Sole D I; Pane, Marika; Mayhew, Anna; Mercuri, Eugenio
The identification of dystrophin and the causative role of mutations in this gene in Duchenne and Becker muscular dystrophies (D/BMD) was expected to lead to timely development of effective therapies. Despite over 20 years of research, corticosteroids remain the only available pharmacological treatment for DMD, although significant benefits and extended life have resulted from advances in the clinical care and management of DMD individuals. Effective treatment of DMD will require dystrophin restitution in skeletal, cardiac, and smooth muscles and nonmuscle tissues; however, modulation of muscle loss and regeneration has the potential to play an important role in altering the natural history of DMD, particularly in combination with other treatments. Emerging biological, molecular, and small molecule therapeutics are showing promise in ameliorating this devastating disease, and it is anticipated that regulatory environments will need to display some flexibility in order to accommodate the new treatment paradigms.
Wilton, Steve D; Fletcher, Sue
Telomeres may regulate human disease by at least two independent mechanisms. 1) Replicative senescence occurs once short telomeres generate DNA damage signals that produce a barrier to tumor progression. 2) Telomere Position Effect (TPE) can change gene expression at intermediate telomere lengths in cultured human cells. We here report a human disease, facioscapulohumeral muscular dystrophy (FSHD) where telomere length may well contribute to its pathogenesis. FSHD is age-related and genetically only 25-60 kb from the end of chromosome 4q. We used a floxable telomerase to generate isogenic clones with different telomere lengths from patients and their unaffected siblings. DUX4, the primary candidate for FSHD pathogenesis, is upregulated >10-fold in FSHD myoblasts-myotubes with short versus long telomeres, and its expression is inversely proportional to telomere length. FSHD may represent a human disease in which TPE contributes to its age-related phenotype.
Stadler, Guido; Rahimov, Fedik; King, Oliver D.; Chen, Jennifer C. J.; Robin, Jerome D.; Wagner, Kathryn R.; Shay, Jerry W.; Emerson, Charles P.; Wright, Woodring E.
A European case of laminin alpha2 deficiency-associated muscular dystrophy in a 12-month-old, female Maine coon pedigree cat is reported. The history and eventual clinical presentation of this cat differed from those of two cats reported in the USA. In this case, the myopathy was characterised by progressively worsening weakness, muscle atrophy and joint contracture. Tendon reflexes were diminished, and motor nerve conduction velocities were slowed. Muscle biopsy demonstrated a dystrophic phenotype with endomysial fibrosis. Occasional thinly myelinated nerve fibres were present within a peripheral nerve specimen. Poorly myelinated fibres were also found at the root level on necropsy specimens. Immunohistochemical staining revealed the absence of laminin alpha2. The cat's family history did not indicate genetic transmission of the disease. PMID:14692554
Poncelet, L; Résibois, A; Engvall, E; Shelton, G D
Background Cardioembolic stroke is an under-recognized complication in patients with limb-girdle muscular dystrophy 1B. Here we present a young stroke patient who had a novel lamin A/C gene (LMNA) mutation. Case presentation This is a 39-year-old man who had slowly progressive proximal muscle weakness and cardiac arrhythmia since adolescent and a family history of similar manifestation. He sustained acute ischemic stroke in the left middle cerebral artery territory. Intravenous recombinant tissue plasminogen activator therapy was given with significant neurological improvement. Additionally, genetic sequencing of the LMNA gene of the patient identified a mutation in c.513+1 G>A that resulted in a splicing aberration. Conclusion We suggested that LMNA gene related myopathies should be considered in young stroke patients with long-standing myopathic features.
Thirty-three young boys (mean age 3.42 years) with Duchenne muscular dystrophy (DMD) and 21 normal control boys (mean age 3.51 years) were studied prospectively to determine whether it is possible to objectively assess locomotor function in young boys with DMD so that they can be included in treatment trials. An initial reproducibility study using a hand-held myometer demonstrated that this method was not useful. The Hammersmith Motor Ability Score demonstrated an increase in developmental abilities with age which was markedly different from normal. The locomotor quotient of the Griffiths' Scales demonstrated a deterioration of quotient scores and is a useful method of assessment that could be used in treatment trials involving young boys with DMD. Sample size planning for treatment trials is discussed. PMID:1870637
Smith, R A; Newcombe, R G; Sibert, J R; Harper, P S
The molecular mechanism of muscle degeneration in a lethal muscle disorder Duchene muscular dystrophy (DMD) has not been fully elucidated. The dystrophic dog, a model of DMD, shows a high mortality rate with a marked increase in serum creatine kinase (CK) levels in the neonatal period. By measuring serum CK levels in cord and venous blood, we found initial pulmonary respiration resulted in massive diaphragm damage in the neonates and thereby lead to the high serum CK levels. Furthermore, molecular biological techniques revealed that osteopontin was prominently upregulated in the dystrophic diaphragm prior to the respiration, and that immediate-early genes (c-fos and egr-1) and inflammation/immune response genes (IL-6, IL-8, COX-2, and selectin E) were distinctly overexpressed after the damage by the respiration. Hence, we segregated dystrophic phases at the molecular level before and after mechanical damage. These molecules could be biomarkers of muscle damage and potential targets in pharmaceutical therapies. PMID:23851606
Nakamura, Akinori; Kobayashi, Masanori; Kuraoka, Mutsuki; Yuasa, Katsutoshi; Yugeta, Naoko; Okada, Takashi; Takeda, Shin'ichi
Introduction: Duchenne muscular dystrophy (DMD) is a lethal genetic disease caused by mutations in the dystrophin gene resulting in chronic muscle damage, muscle wasting, and premature death. Utrophin is a dystrophin protein homologue that increases dystrophic muscle function and reduces pathology. Currently, no treatments that increase utrophin protein expression exist. However, exercise increases utrophin mRNA expression in healthy humans. Therefore, the purpose was to determine whether exercise increases utrophin protein expression in dystrophic muscle. Methods: Utrophin protein was measured in the quadriceps and soleus muscles of mdx mice after 12 weeks of voluntary wheel running exercise or sedentary controls. Muscle pathology was measured in the quadriceps. Results: Exercise increased utrophin protein expression 334?±?63% in the quadriceps relative to sedentary controls. Exercise increased central nuclei 4?±?1% but not other measures of pathology. Conclusions: Exercise may be an intervention that increases utrophin expression in patients with DMD. Muscle Nerve 49: 915-918, 2014. PMID:24375286
Gordon, Bradley S; Lowe, Dawn A; Kostek, Matthew C
We describe the case of a 17-year-old boy with Becker's muscular dystrophy (BMD) presenting with rapid progression from hypertrophic cardiomyopathy to heart failure within 2 years. Initial echocardiogram showed severe hypertrophy of left ventricle (LV) and right ventricle (RV) with normal chamber size, and preserved LV systolic function. Microscopic study of cardiac muscle obtained by endomyocardial biopsy of the interventricular septum showed severe hypertrophy of the muscle fibers and interstitial fibrosis. Follow-up echocardiogram 2 years after the first examination exhibited marked dilated LV and RV with severe LV global hypokinesia. Follow-up endomyocardial biopsy demonstrated increased interstitial cellular matrix. Immunohistochemical staining for dystrophin revealed significant loss of dystrophin along the sarcoplasmic membrane of the right biceps brachii muscle, compatible with BMD. PMID:15921812
Park, Ok Young; Ahn, Youngkeun; Park, Woo Seok; Lim, Ji Hyun; Park, Hyung Wook; Kim, Ju Han; Hong, Young Joon; Kim, Weon; Jeong, Myung Ho; Cho, Jeong Gwan; Park, Jong Chun; Lee, Min Cheol; Kang, Jung Chaee
Telomeres may regulate human disease by at least two independent mechanisms. First, replicative senescence occurs once short telomeres generate DNA-damage signals that produce a barrier to tumor progression. Second, telomere position effects (TPE) could change gene expression at intermediate telomere lengths in cultured human cells. Here we report that telomere length may contribute to the pathogenesis of facioscapulohumeral muscular dystrophy (FSHD). FSHD is a late-onset disease genetically residing only 25-60 kilobases from the end of chromosome 4q. We used a floxable telomerase to generate isogenic clones with different telomere lengths from affected patients and their unaffected siblings. DUX4, the primary candidate for FSHD pathogenesis, is upregulated over ten-fold in FSHD myoblasts and myotubes with short telomeres, and its expression is inversely proportional to telomere length. FSHD may be the first known human disease in which TPE contributes to age-related phenotype. PMID:23644600
Stadler, Guido; Rahimov, Fedik; King, Oliver D; Chen, Jennifer C J; Robin, Jerome D; Wagner, Kathryn R; Shay, Jerry W; Emerson, Charles P; Wright, Woodring E
This study explored the problems encountered by parents in caring for children with Duchenne muscular dystrophy (DMD). Open questionnaires (N=21) designed to identify and gauge stress factors were used to collect study data. Results showed that key elements of the care stress model in parents of DMD children prior to joining a support group included: (1) recognition of the factors underlying the changes in their child's health condition (incomprehension, inference, rationalization, and acceptance of mutation and sexual heredity); (2) special assistance needs such as barrier-free facilities, government/social assistance (role substitution, coordination, and long-term care) and medical information (on treating disease causes, psychological adjustment, rehabilitation, and the welfare system); and (3) strains (physical, psychological, sleep disturbances, and feelings of powerlessness). Once families of DMD children began participating in DMD support groups, it is important to note the information exchanged, particularly with regard to medical, rehabilitation, psychological adjustment, role substitution, and welfare benefit information. PMID:16767622
Chen, Jih-Yuan; Jong, Yuh-Jyh
The aim of this study was to analyze previously published gene expression data of skeletal muscle biopsies of Duchenne muscular dystrophy (DMD) patients and controls (Gene Expression Omnibus database, accession #GSE6011) using systems biology approaches. We applied an unsupervised method to discriminate patient and control populations, based on principal component analysis, using the gene expressions as units and patients as variables. The genes having the highest absolute scores in the discrimination between the groups, were then analyzed in terms of gene expression networks, on the basis of their mutual correlation in the two groups. The correlation network structures suggest two different modes of gene regulation in the two groups, reminiscent of important aspects of DMD pathogenesis. PMID:23530089
Bernardini, Camilla; Censi, Federica; Lattanzi, Wanda; Calcagnini, Giovanni; Giuliani, Alessandro
Overt cardiac involvement in Duchenne muscular dystrophy (DMD) typically occurs later in the disease. The primary aim was to estimate the proportion of young (<6 years of age) DMD patients with manifestations of cardiac disease by electrocardiography (ECG). Secondary aims were to assess associations between ECG abnormalities and evidence of cardiac disease by echocardiography, as well as to estimate the relationship between dystrophin mutation site and an abnormal ECG. Seventy eight steroid-naive DMD patients <6 years of age were identified. ECG abnormalities were identified in 78%, with LV pathology being the most commonly identified pattern. Only one echocardiogram was abnormal. There was no statistically significant relationship identified between ECG abnormalities and dystrophin genotype. ECG abnormalities are common in very young DMD patients, signaling cardiac involvement well before the onset of clinical symptoms. PMID:21571532
James, Jeanne; Kinnett, Kathleen; Wang, Yu; Ittenbach, Richard F; Benson, D Woodrow; Cripe, Linda
Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disorder caused by mutations in the dystrophin DMD gene located at Xp21.1 region. Up to 65% of the patients present dystrophin gene deletions. Mothers of DMD patients have a two-thirds chance of carrying a dystrophin mutation. The female carrier will transmit the disease gene to half of her sons and half of her daughters. As the recurrence risk for the disease is extremely high, it is very important to detect carrier status among female relatives of the patients to bring an adequate genetic counseling. In this work, results from two methods to identify female carriers are presented. One method is a multicolor fluorescence in situ hybridization (FISH) assay, and the other is reverse transcriptase-polymerase chain reaction (RT-PCR). We showed that FISH is an efficient, sensitive method that brings confident results to detect DMD female carriers as compared to RT-PCR. PMID:18471087
Velázquez-Wong, Ana Claudia; Hernández-Huerta, César; Márquez-Calixto, Areli; Hernández-Aguilar, Fidel Omar; Rodríguez-Cruz, Maricela; Salamanca-Gómez, Fabio; Coral-Vázquez, Ramón
The chromosomes of a male patient who suffers from Duchenne muscular dystrophy (DMD) with a molecular deletion were examined with an improved high resolution R type replication banding technique. High resolution cytogenetic analysis of the proband revealed a deletion of the Xp21.13 subband. His healthy mother was heterozygous for the deletion, which is subject to random X inactivation in lymphocytes. The X chromosomes of the proband's grandmother were normal, suggesting that the deletion of the Xp21.13 subband in the mother was a new mutation. The finding of a very small, cytologically visible Xp21.1 deletion in a male DMD patient with a molecular deletion emphasises the importance of resolving the fine structure in the Xp21 region. PMID:3294410
Werner, W; Spiegler, A W
In 1988, we familiarised ourselves at Poitiers with the concept of operative treatment of the lower limbs and the spine in Duchenne muscular dystrophy (DMD) patients which Yves Rideau and his collaborators had developed there in the early 1980s. Thereupon, we immediately established the techniques at our home universities, first at the Technische Universität Aachen and, from 1999 on, at the Universitätsklinikum Erlangen, Germany. Since then, we have applied the technique to more than 500 DMD patients in total by performing more than 800 operations on the lower limbs and/or spine. In support of findings reported by Professor Rideau in this issue we observed that, where patients are still ambulatory at the time of operation, the operation delays the point at which patients become wheelchair-bound by about two years. Likewise, patients receiving this treatment were/are also able to perform the Gowers' manoeuvre for around two years longer. PMID:22655513
Forst, Jürgen; Forst, Raimund
Limb-girdle muscular dystrophy types 2E and F are characterized by skeletal muscle weakness and often cardiomyopathy and are due to mutations in the genes encoding beta- and delta-sarcoglycan. We previously demonstrated that loss of sarcoglycans in smooth muscle leads to constrictions of the microvasculature that contributes to the cardiac phenotype. It is unclear how vasculature abnormalities affect skeletal muscle. We injected recombinant beta- or delta-sarcoglycan adenoviruses into skeletal muscles of corresponding null mice. We hypothesized that the adenoviruses would not transduce vascular smooth muscle, and we would only target skeletal muscle. Indeed, sustained expression of intact sarcoglycan-sarcospan complex was noted at the sarcolemma, neuromuscular junction, myotendinous junction, and in peripheral nerve, but not in vascular smooth muscle. Gene transfer of the corresponding deleted sarcoglycan gene preserved sarcolemmal integrity, prevented pathological dystrophy and hypertrophy, and protected against exercised-induced damage. We conclude that vascular dysfunction is not a primary cause of beta- and delta-sarcoglycan-deficient muscular dystrophy. In addition, we show successful functional rescue of entire muscles after adenovirus-mediated gene delivery. Thus, virus-mediated gene transfer of sarcoglycans to skeletal muscle in combination with pharmacological prevention of cardiomyopathy constitute promising therapeutic strategies for limb-girdle muscular dystrophies. PMID:12851463
Durbeej, Madeleine; Sawatzki, Shanna M; Barresi, Rita; Schmainda, Kathleen M; Allamand, Valérie; Michele, Daniel E; Campbell, Kevin P
Aims The mdx mouse has proven to be useful in understanding the cardiomyopathy that frequently occurs in muscular dystrophy patients. Here we employed a comprehensive array of clinically relevant in vivo MRI techniques to identify early markers of cardiac dysfunction and follow disease progression in the hearts of mdx mice. Methods and Results Serial measurements of cardiac morphology and function were made in the same group of mdx mice and controls (housed in a non-SPF facility) using MRI at 1, 3, 6, 9 and 12 months after birth. Left ventricular (LV) and right ventricular (RV) systolic and diastolic function, response to dobutamine stress and myocardial fibrosis were assessed. RV dysfunction preceded LV dysfunction, with RV end systolic volumes increased and RV ejection fractions reduced at 3 months of age. LV ejection fractions were reduced at 12 months, compared with controls. An abnormal response to dobutamine stress was identified in the RV of mdx mice as early as 1 month. Late-gadolinium-enhanced MRI identified increased levels of myocardial fibrosis in 6, 9 and 12-month-old mdx mice, the extent of fibrosis correlating with the degree of cardiac remodeling and hypertrophy. Conclusions MRI could identify cardiac abnormalities in the RV of mdx mice as young as 1 month, and detected myocardial fibrosis at 6 months. We believe these to be the earliest MRI measurements of cardiac function reported for any mice, and the first use of late-gadolinium-enhancement in a mouse model of congenital cardiomyopathy. These techniques offer a sensitive and clinically relevant in vivo method for assessment of cardiomyopathy caused by muscular dystrophy and other diseases.
Stuckey, Daniel J.; Carr, Carolyn A.; Camelliti, Patrizia; Tyler, Damian J.; Davies, Kay E.; Clarke, Kieran
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder in which the loss of dystrophin causes progressive degeneration of skeletal and cardiac muscle. Potential therapies that carry substantial risk, such as gene and cell-based approaches, must first be tested in animal models, notably the mdx mouse and several dystrophin-deficient breeds of dogs, including golden retriever muscular dystrophy (GRMD). Affected dogs have a more severe phenotype, in keeping with that of DMD, so may better predict disease pathogenesis and treatment efficacy. We and others have developed various phenotypic tests to characterize disease progression in the GRMD model. These biomarkers range from measures of strength and joint contractures to magnetic resonance imaging. Some of these tests are routinely used in clinical veterinary practice, while others require specialized equipment and expertise. By comparing serial measurements from treated and untreated groups, one can document improvement or delayed progression of disease. Potential treatments for DMD may be broadly categorized as molecular, cellular, or pharmacologic. The GRMD model has increasingly been used to assess efficacy of a range of these therapies. While some of these studies have largely provided general proof-of-concept for the treatment under study, others have demonstrated efficacy using the biomarkers discussed. Importantly, just as symptoms in DMD vary among patients, GRMD dogs display remarkable phenotypic variation. While confounding statistical analysis in preclinical trials, this variation offers insight regarding the role that modifier genes play in disease pathogenesis. By correlating functional and mRNA profiling results, gene targets for therapy development can be identified.
Kornegay, Joe N.; Bogan, Janet R.; Bogan, Daniel J.; Childers, Martin K.; Li, Juan; Nghiem, Peter; Detwiler, David A.; Larsen, C. Aaron; Grange, Robert W.; Bhavaraju-Sanka, Ratna K.; Tou, Sandra; Keene, Bruce P.; Howard, James F.; Wang, Jiahui; Fan, Zheng; Schatzberg, Scott J.; Styner, Martin A.; Flanigan, Kevin M.; Xiao, Xiao; Hoffman, Eric P.
Mutations in several known or putative glycosyltransferases cause glycosylation defects in ?-dystroglycan (?-DG), an integral component of the dystrophin glycoprotein complex. The hypoglycosylation reduces the ability of ?-DG to bind laminin and other extracellular matrix ligands and is responsible for the pathogenesis of an inherited subset of muscular dystrophies known as the dystroglycanopathies. By exome and Sanger sequencing we identified two individuals affected by a dystroglycanopathy with mutations in ?-1,3-N-acetylgalactosaminyltransferase 2 (B3GALNT2). B3GALNT2 transfers N-acetyl galactosamine (GalNAc) in a ?-1,3 linkage to N-acetyl glucosamine (GlcNAc). A subsequent study of a separate cohort of individuals identified recessive mutations in four additional cases that were all affected by dystroglycanopathy with structural brain involvement. We show that functional dystroglycan glycosylation was reduced in the fibroblasts and muscle (when available) of these individuals via flow cytometry, immunoblotting, and immunocytochemistry. B3GALNT2 localized to the endoplasmic reticulum, and this localization was perturbed by some of the missense mutations identified. Moreover, knockdown of b3galnt2 in zebrafish recapitulated the human congenital muscular dystrophy phenotype with reduced motility, brain abnormalities, and disordered muscle fibers with evidence of damage to both the myosepta and the sarcolemma. Functional dystroglycan glycosylation was also reduced in the b3galnt2 knockdown zebrafish embryos. Together these results demonstrate a role for B3GALNT2 in the glycosylation of ?-DG and show that B3GALNT2 mutations can cause dystroglycanopathy with muscle and brain involvement.
Stevens, Elizabeth; Carss, Keren J.; Cirak, Sebahattin; Foley, A. Reghan; Torelli, Silvia; Willer, Tobias; Tambunan, Dimira E.; Yau, Shu; Brodd, Lina; Sewry, Caroline A.; Feng, Lucy; Haliloglu, Goknur; Orhan, Diclehan; Dobyns, William B.; Enns, Gregory M.; Manning, Melanie; Krause, Amanda; Salih, Mustafa A.; Walsh, Christopher A.; Hurles, Matthew; Campbell, Kevin P.; Manzini, M. Chiara; Stemple, Derek; Lin, Yung-Yao; Muntoni, Francesco
Muscular dystrophies (MDs) such as Duchenne muscular dystrophy (DMD), sarcoglycanopathy (Sgpy) and dysferlinopathy (Dysfy) are recessive genetic neuromuscular diseases that display muscle degeneration. Although these MDs have comparable endpoints of muscle pathology, the onset, severity and the course of these diseases are diverse. Different mechanisms downstream of genetic mutations might underlie the disparity in these pathologies. We surmised that oxidative damage and altered antioxidant function might contribute to these differences. The oxidant and antioxidant markers in the muscle biopsies from patients with DMD (n = 15), Sgpy (n = 15) and Dysfy (n = 15) were compared to controls (n = 10). Protein oxidation and lipid peroxidation was evident in all MDs and correlated with the severity of pathology, with DMD, the most severe dystrophic condition showing maximum damage, followed by Sgpy and Dysfy. Oxidative damage in DMD and Sgpy was attributed to the depletion of glutathione (GSH) and lowered antioxidant activities while loss of GSH peroxidase and GSH-S-transferase activities was observed in Dysfy. Lower GSH level in DMD was due to lowered activity of gamma-glutamyl cysteine ligase, the rate limiting enzyme in GSH synthesis. Similar analysis in cardiotoxin (CTX) mouse model of MD showed that the dystrophic muscle pathology correlated with GSH depletion and lipid peroxidation. Depletion of GSH prior to CTX exposure in C2C12 myoblasts exacerbated oxidative damage and myotoxicity. We deduce that the pro and anti-oxidant mechanisms could be correlated to the severity of MD and might influence the dystrophic pathology to a different extent in various MDs. On a therapeutic note, this could help in evolving novel therapies that offer myoprotection in MD. PMID:22219131
Renjini, R; Gayathri, N; Nalini, A; Srinivas Bharath, M M
Facioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy characterized by an asymmetric progressive weakness and wasting of the facial, shoulder and upper arm muscles, frequently accompanied by hearing loss and retinal vasculopathy. FSHD is an autosomal dominant disease linked to chromosome 4q35, but the causative gene remains controversial. DUX4 is a leading candidate gene as causative of FSHD. However, DUX4 expression is extremely low in FSHD muscle, and there is no DUX4 animal model that mirrors the pathology in human FSHD. Here, we show that the misexpression of very low levels of human DUX4 in zebrafish development recapitulates the phenotypes seen in human FSHD patients. Microinjection of small amounts of human full-length DUX4 (DUX4-fl) mRNA into fertilized zebrafish eggs caused asymmetric abnormalities such as less pigmentation of the eyes, altered morphology of ears, developmental abnormality of fin muscle, disorganization of facial musculature and/or degeneration of trunk muscle later in development. Moreover, DUX4-fl expression caused aberrant localization of myogenic cells marked with ?-actin promoter-driven enhanced green fluorescent protein outside somite boundary, especially in head region. These abnormalities were rescued by coinjection of the short form of DUX4 (DUX4-s). Our results suggest that the misexpression of DUX4-fl, even at extremely low level, can recapitulate the phenotype observed in FSHD patients in a vertebrate model. These results strongly support the current hypothesis for a role of DUX4 in FSHD pathogenesis. We also propose that DUX4 expression during development is important for the pathogenesis of FSHD. PMID:23108159
Mitsuhashi, Hiroaki; Mitsuhashi, Satomi; Lynn-Jones, Taylor; Kawahara, Genri; Kunkel, Louis M
Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder caused by mutations in the dystrophin gene that result in the absence of the membrane-stabilizing protein dystrophin. Dystrophin-deficient muscle fibres are fragile and susceptible to an influx of Ca(2+), which activates inflammatory and muscle degenerative pathways. At present there is no cure for DMD, and existing therapies are ineffective. Here we show that increasing the expression of intramuscular heat shock protein 72 (Hsp72) preserves muscle strength and ameliorates the dystrophic pathology in two mouse models of muscular dystrophy. Treatment with BGP-15 (a pharmacological inducer of Hsp72 currently in clinical trials for diabetes) improved muscle architecture, strength and contractile function in severely affected diaphragm muscles in mdx dystrophic mice. In dko mice, a phenocopy of DMD that results in severe spinal curvature (kyphosis), muscle weakness and premature death, BGP-15 decreased kyphosis, improved the dystrophic pathophysiology in limb and diaphragm muscles and extended lifespan. We found that the sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA, the main protein responsible for the removal of intracellular Ca(2+)) is dysfunctional in severely affected muscles of mdx and dko mice, and that Hsp72 interacts with SERCA to preserve its function under conditions of stress, ultimately contributing to the decreased muscle degeneration seen with Hsp72 upregulation. Treatment with BGP-15 similarly increased SERCA activity in dystrophic skeletal muscles. Our results provide evidence that increasing the expression of Hsp72 in muscle (through the administration of BGP-15) has significant therapeutic potential for DMD and related conditions, either as a self-contained therapy or as an adjuvant with other potential treatments, including gene, cell and pharmacological therapies. PMID:22495301
Gehrig, Stefan M; van der Poel, Chris; Sayer, Timothy A; Schertzer, Jonathan D; Henstridge, Darren C; Church, Jarrod E; Lamon, Severine; Russell, Aaron P; Davies, Kay E; Febbraio, Mark A; Lynch, Gordon S
Human induced pluripotent stem cells (iPSCs) represent a scalable source of potentially any cell type for disease modeling and therapeutic screening. We have a particular interest in modeling skeletal muscle from various genetic backgrounds; however, efficient and reproducible methods for the myogenic differentiation of iPSCs have not previously been demonstrated. Ectopic myogenic differentiation 1 (MyoD) expression has been shown to induce myogenesis in primary cell types, but the same effect has been unexpectedly challenging to reproduce in human iPSCs. In this study, we report that optimization of culture conditions enabled direct MyoD-mediated differentiation of iPSCs into myoblasts without the need for an intermediate step or cell sorting. MyoD induction mediated efficient cell fusion of mature myocytes yielding multinucleated myosin heavy chain-positive myotubes. We applied the same approach to dystrophic iPSCs, generating 16 iPSC lines from fibroblasts of four patients with Duchenne and Becker muscular dystrophies. As seen with iPSCs from healthy donors, within 36 hours from MyoD induction there was a clear commitment toward the myogenic identity by the majority of iPSCs in culture (50%-70%). The patient iPSC-derived myotubes successfully adopted the skeletal muscle program, as determined by global gene expression profiling, and were functionally responsive to treatment with hypertrophic proteins insulin-like growth factor 1 (IGF-1) and wingless-type MMTV integration site family, member 7A (Wnt7a), which are being investigated as potential treatments for muscular dystrophy in clinical and preclinical studies, respectively. Our results demonstrate that iPSCs have no intrinsic barriers preventing MyoD from inducing efficient and rapid myogenesis and thus providing a scalable source of normal and dystrophic myoblasts for use in disease modeling and drug discovery. PMID:24396035
Abujarour, Ramzey; Bennett, Monica; Valamehr, Bahram; Lee, Tom Tong; Robinson, Megan; Robbins, David; Le, Thuy; Lai, Kevin; Flynn, Peter
The progressive loss of muscle mass characteristic of many muscular dystrophies impairs the efficacy of most of the gene and molecular therapies currently being pursued for the treatment of those disorders. It is becoming increasingly evident that a therapeutic application, to be effective, needs to target not only mature myofibers, but also muscle progenitors cells or muscle stem cells able to form new muscle tissue and to restore myofibers lost as the result of the diseases or during normal homeostasis so as to guarantee effective and lost lasting effects. Correction of the genetic defect using oligodeoxynucleotides (ODNs) or engineered nucleases holds great potential for the treatment of many of the musculoskeletal disorders. The encouraging results obtained by studying in vitro systems and model organisms have set the groundwork for what is likely to become an emerging field in the area of molecular and regenerative medicine. Furthermore, the ability to isolate and expand from patients various types of muscle progenitor cells capable of committing to the myogenic lineage provides the opportunity to establish cell lines that can be used for transplantation following ex vivo manipulation and expansion. The purpose of this article is to provide a perspective on approaches aimed at correcting the genetic defect using gene editing strategies and currently under development for the treatment of Duchenne muscular dystrophy (DMD), the most sever of the neuromuscular disorders. Emphasis will be placed on describing the potential of using the patient own stem cell as source of transplantation and the challenges that gene editing technologies face in the field of regenerative biology.
Objective Facioscapulohumeral muscular dystrophy (FSHD) is associated with D4Z4 repeat contraction on human chromosome 4q35. This genetic lesion does not result in complete loss or mutation of any gene. Consequently, the pathogenic mechanisms underlying FSHD have been difficult to discern. In leading FSHD pathogenesis models, D4Z4 contractions are proposed to cause epigenetic changes, which ultimately increase expression of genes with myopathic potential. Although no gene has been conclusively linked to FSHD development, recent evidence supports a role for the D4Z4-encoded DUX4 gene in FSHD. In this study, our objective was to test the in vivo myopathic potential of DUX4. Methods We delivered DUX4 to zebrafish and mouse muscle by transposon-mediated transgenesis and adeno-associated viral vectors, respectively. Results Overexpression of DUX4, which encodes a transcription factor, caused abnormalities associated with muscular dystrophy in zebrafish and mice. This toxicity required DNA binding, because a DUX4 DNA binding domain mutant produced no abnormalities. Importantly, we found the myopathic effects of DUX4 were p53 dependent, as p53 inhibition mitigated DUX4 toxicity in vitro, and muscles from p53 null mice were resistant to DUX4-induced damage. Interpretation Our work demonstrates the myopathic potential of DUX4 in animal muscle. Considering previous studies showed DUX4 was elevated in FSHD patient muscles, our data support the hypothesis that DUX4 overexpression contributes to FSHD development. Moreover, we provide a p53-dependent mechanism for DUX4 toxicity that is consistent with previous studies showing p53 pathway activation in FSHD muscles. Our work justifies further investigation of DUX4 and the p53 pathway in FSHD pathogenesis.
Wallace, Lindsay M.; Garwick, Sara E.; Mei, Wenyan; Belayew, Alexandra; Coppee, Frederique; Ladner, Katherine J.; Guttridge, Denis; Yang, Jing; Harper, Scott Q.
Duchenne muscular dystrophy (DMD) patients exhibit skeletal muscle weakness with continuous cycles of muscle fiber degeneration/regeneration, chronic inflammation, low bone mineral density, and increased risks of fracture. Fragility fractures and associated complications are considered as a consequence of the osteoporotic condition in these patients. Here, we aimed to establish the relationship between muscular dystrophy and fracture healing by assessing bone regeneration in mdx mice, a model of DMD with absence of osteoporosis. Our results illustrate that muscle defects in mdx mice impact the process of bone regeneration at various levels. In mdx fracture calluses, both cartilage and bone deposition were delayed followed by a delay in cartilage and bone remodeling. Vascularization of mdx fracture calluses was also decreased during the early stages of repair. Dystrophic muscles are known to contain elevated numbers of macrophages contributing to muscle degeneration. Accordingly, we observed increased macrophage recruitment in the mdx fracture calluses and abnormal macrophage accumulation throughout the process of bone regeneration. These changes in the inflammatory environment subsequently had an impact on the recruitment of osteoclasts and the remodeling phase of repair. Further damage to the mdx muscles, using a novel model of muscle trauma, amplified both the chronic inflammatory response and the delay in bone regeneration. In addition, PLX3397 treatment of mdx mice, a cFMS (colony stimulating factor receptor 1) inhibitor in monocytes, partially rescued the bone repair defect through increasing cartilage deposition and decreasing the number of macrophages. In conclusion, chronic inflammation in mdx mice contributes to the fracture healing delay and is associated with a decrease in angiogenesis and a transient delay in osteoclast recruitment. By revealing the role of dystrophic muscle in regulating the inflammatory response during bone repair, our results emphasize the implication of muscle in the normal bone repair process and may lead to improved treatment of fragility fractures in DMD patients. PMID:23857747
Abou-Khalil, Rana; Yang, Frank; Mortreux, Marie; Lieu, Shirley; Yu, Yan-Yiu; Wurmser, Maud; Pereira, Catia; Relaix, Frédéric; Miclau, Theodore; Marcucio, Ralph S; Colnot, Céline
The activity of glutathione peroxidase, a selenium containing enzyme, was measured in the blood of horses to determine its usefulness as an indicator of selenium status. In 15 horses the enzyme activity was positively related to the blood selenium concentration (P less than .001, r-0.98) over the range of enzyme activities of 8.2 to 140 units (mumoles NADP-oxidised/min/gHb) and selenium concentrations of 0.24 to 2.74 mumol/l. In a group of 8 horses which 2 foals had died with lesions of muscular dystrophy the enzyme activity increased from a mean of 11.8 units before treatment with selenium to 34.5 units after 2 intravenous injections of sodium selenite given one month apart. Another group of 8 horses grazing paddocks adjacent to this affected group did not receive any selenium treatment and had a mean enzyme activity of 11.9 units. Blood glutathione peroxidase activity was measured in 50 pasture-fed horses and 180 stall-fed horses. The range of activities found (7 to 158 units) indicated that selenium intake in horses varied widely between localities. All pasture-fed horses grazing areas where muscular dystrophy had occurred in foals had low activities (less than 20 units). In stall-fed horses the enzyme activity was influenced by selenium treatment, and horses which had been treated usually had higher activities than horses in the same stable with no history of selenium treatment. It was concluded that blood glutathione peroxidase is a suitable indicator of selenium status in horses. PMID:655982
Caple, I W; Edwards, S J; Forsyth, W M; Whiteley, P; Selth, R H; Fulton, L J
Objective: Duchenne muscular dystrophy (DMD) is the most common single-gene lethal disorder. Substantial patient–patient variability in disease onset and progression and response to glucocorticoids is seen, suggesting genetic or environmental modifiers. Methods: Two DMD cohorts were used as test and validation groups to define genetic modifiers: a Padova longitudinal cohort (n = 106) and the Cooperative International Neuromuscular Research Group (CINRG) cross-sectional natural history cohort (n = 156). Single nucleotide polymorphisms to be genotyped were selected from mRNA profiling in patients with severe vs mild DMD, and genome-wide association studies in metabolism and polymorphisms influencing muscle phenotypes in normal volunteers were studied. Results: Effects on both disease progression and response to glucocorticoids were observed with polymorphism rs28357094 in the gene promoter of SPP1 (osteopontin). The G allele (dominant model; 35% of subjects) was associated with more rapid progression (Padova cohort log rank p = 0.003), and 12%–19% less grip strength (CINRG cohort p = 0.0003). Conclusions: Osteopontin genotype is a genetic modifier of disease severity in Duchenne dystrophy. Inclusion of genotype data as a covariate or in inclusion criteria in DMD clinical trials would reduce intersubject variance, and increase sensitivity of the trials, particularly in older subjects.
Pegoraro, E.; Hoffman, E.P.; Piva, L.; Gavassini, B.F.; Cagnin, S.; Ermani, M.; Bello, L.; Soraru, G.; Pacchioni, B.; Bonifati, M.D.; Lanfranchi, G.; Angelini, C.; Kesari, A.; Lee, I.; Gordish-Dressman, H.; Devaney, J.M.; McDonald, C.M.
Background Although muscular dystrophy causes muscle weakness and muscle loss, the role of exercise in the management of this disease remains controversial. Objective The purpose of this systematic review is to evaluate the role of exercise interventions on muscle strength in patients with muscular dystrophy. Methods We performed systematic electronic searches in Medline, Embase, Web of Science, Scopus and Pedro as well as a list of reference literature. We included trials assessing muscle exercise in patients with muscular dystrophy. Two reviewers independently abstracted data and appraised risk of bias. Results We identified five small (two controlled and three randomized clinical) trials comprising 242 patients and two ongoing randomized controlled trials. We were able to perform two meta-analyses. We found an absence of evidence for a difference in muscle strength (MD 4.18, 95% CIs - 2.03 to 10.39; p?=?0.91) and in endurance (MD ?0.53, 95% CIs –1.11 to 0.05; p?=?0.26). In both, the direction of effects favored muscle exercise. Conclusions The first included trial about the efficacy of muscular exercise was published in 1978. Even though some benefits of muscle exercise were consistently reported across studies, the benefits might be due to the small size of studies and other biases. Detrimental effects are still possible. After several decades of research, doctors cannot give advice and patients are, thus, denied basic information. A multi-center randomized trial investigating the strength of muscles, fatigue, and functional limitations is needed.
Gianola, Silvia; Pecoraro, Valentina; Lambiase, Simone; Gatti, Roberto; Banfi, Giuseppe; Moja, Lorenzo
Background MDC1A is a congenital neuromuscular disorder with developmentally complex and progressive pathologies that results from a deficiency in the protein laminin ?2. MDC1A is associated with a multitude of pathologies, including increased apoptosis, inflammation and fibrosis. In order to assess and treat a complicated disease such as MDC1A, we must understand the natural history of the disease so that we can identify early disease drivers and pinpoint critical time periods for implementing potential therapies. Results We found that DyW mice show significantly impaired myogenesis and high levels of apoptosis as early as postnatal week 1. We also saw a surge of inflammatory response at the first week, marked by high levels of infiltrating macrophages, nuclear factor ?B activation, osteopontin expression and overexpression of inflammatory cytokines. Fibrosis markers and related pathways were also observed to be elevated throughout early postnatal development in these mice, including periostin, collagen and fibronectin gene expression, as well as transforming growth factor ? signaling. Interestingly, fibronectin was found to be the predominant fibrous protein of the extracellular matrix in early postnatal development. Lastly, we observed upregulation in various genes related to angiotensin signaling. Methods We sought out to examine the dysregulation of various pathways throughout early development (postnatal weeks 1-4) in the DyW mouse, the most commonly used mouse model of laminin-deficient muscular dystrophy. Muscle function tests (stand-ups and retractions) as well as gene (qRT-PCR) and protein levels (western blot, ELISA), histology (H&E, picrosirius red staining) and immunohistochemistry (fibronectin, TUNEL assay) were used to assess dysregulation of matricelluar protieins. Conclusions Our results implicate the involvement of multiple signaling pathways in driving the earliest stages of pathology in DyW mice. As opposed to classical dystrophies, such as Duchenne muscular dystrophy, the dysregulation of various matricellular proteins appears to be a distinct feature of the early progression of DyW pathology. On the basis of our results, we believe that therapies that may reduce apoptosis and stabilize the homeostasis of extracellular matrix proteins may have increased efficacy if started at a very early age.
We recently described a modified version of the 6-minute walk test (6MWT) for Duchenne muscular dystrophy (DMD) based partly on the American Thoracic Society (ATS) guidelines. This measure has shown reliability, validity and utility as a primary outcome measure in DMD clinical trials. Because loss of muscle function in DMD occurs against the background of normal childhood growth and development, younger children with DMD can show increase in distance walked during 6MWT over ~1 year despite progressive muscular impairment. In this study, we compare 6-minute walk distance (6MWD) data from DMD boys (n=17) and typically developing control subjects (n=22) to existing normative data from age- and sex-matched children and adolescents. An age- and height-based equation fitted to normative data by Geiger and colleagues was used to convert 6MWD to a percent-predicted (%-predicted) value in boys with DMD. Analysis of %-predicted 6MWD data represents a method to account for normal growth and development, and shows that gains in function at early ages represents stable rather than improving abilities in boys with DMD. Boys with DMD from 4-7 years of age maintain a stable 6MWD approximately 80% of that of typically developing peers, with the deficit progressing at a variable rate thereafter.
Henricson, Erik; Abresch, Richard; Han, Jay J.; Nicorici, Alina; Goude Keller, Erica; Elfring, Gary; Reha, Allen; Barth, Jay; McDonald, Craig M.
The goal of the current investigation was to examine adaptive behavior and cognitive skills in young children with Duchenne muscular dystrophy (DMD), a genetic disorder that causes progressive muscular weakness and concomitant cognitive deficits. Previous studies have documented specific language deficits in older children with DMD, but there are limited data on younger children. Twenty children with DMD who were between 3 and 6 years old and 20 unaffected family control children were recruited. Parents completed questionnaires relating to development and adaptive functioning, while children completed neuropsychological testing. Results of paired t tests indicate that children with DMD are rated as delayed relative to familial controls on measures of adaptive functioning, as assessed by the Vineland Adaptive Behavior Scales. Furthermore, children with DMD exhibit impairments on multiple measures of cognition, including measures of receptive language, expressive language, visuo-spatial skills, fine-motor skills, attention, and memory skills. Across all domains examined, the young children with DMD performed more poorly than their familial controls. These deficits appear to be more generalized than those reported in older children with this disorder. Dystrophin, a missing protein product, is hypothesized to be responsible for these cognitive and behavioral impairments. PMID:18764980
Cyrulnik, Shana E; Fee, Robert J; Batchelder, Abigail; Kiefel, Jacqueline; Goldstein, Edward; Hinton, Veronica J
Critical to the evaluation of potential therapeutics for muscular disease are sensitive and reproducible physiological assessments of muscle function. Because many pre-clinical trials rely on mouse models for these diseases, isolated muscle function has become one of the standards for Go/NoGo decisions in moving drug candidates forward into patients. We will demonstrate the preparation of the extensor digitorum longus (EDL) and diaphragm muscles for functional testing, which are the predominant muscles utilized for these studies. The EDL muscle geometry is ideal for isolated muscle preparations, with two easily accessible tendons, and a small size that can be supported by superfusion in a bath. The diaphragm exhibits profound progressive pathology in dystrophic animals, and can serve as a platform for evaluating many potential therapies countering fibrosis, and promoting myofiber stability. Protocols for routine testing, including isometric and eccentric contractions, will be shown. Isometric force provides assessment of strength, and eccentric contractions help to evaluate sarcolemma stability, which is disrupted in many types of muscular dystrophies. Comparisons of the expected results between muscles from wildtype and dystrophic muscles will also be provided. These measures can complement morphological and biochemical measurements of tissue homeostasis, as well as whole animal assessments of muscle function. PMID:23407283
Moorwood, Catherine; Liu, Min; Tian, Zuozhen; Barton, Elisabeth R
Duchenne muscular dystrophy (DMD) is an X-linked recessive disease caused by mutations in the dystrophin gene and is characterized by muscle degeneration and death. DMD affects males; females being asymptomatic carriers of mutations. However, some of them manifest symptoms due to a translocation between X chromosome and an autosome or to a heterozygous mutation leading to inactivation of most of their normal X chromosome. Six symptomatic female carriers and two asymptomatic were analyzed by: I) Segregation of STRs-(CA)n and MLPA assays to detect a hemizygous alteration, and II) X chromosome inactivation pattern to uncover the reason for symptoms in these females. The symptomatic females shared mild but progressive muscular weakness and increased serum creatin kinase (CK) levels. Levels of dystrophin protein were below normal or absent in many fibers. Segregation of STRs-(CA)n revealed hemizygous patterns in three patients, which were confirmed by MLPA. In addition, this analysis showed a duplication in another patient. X chromosome inactivation assay revealed a skewed X inactivation pattern in the symptomatic females and a random inactivation pattern in the asymptomatic ones. Our results support the hypothesis that the DMD phenotype in female carriers of a dystrophin mutation has a direct correlation with a skewed X-chromosome inactivation pattern. PMID:24135430
Giliberto, Florencia; Radic, Claudia Pamela; Luce, Leonela; Ferreiro, Verónica; de Brasi, Carlos; Szijan, Irene
To identify serum biomarkers that allow monitoring of disease progression and treatment effects in Duchenne muscular dystrophy (DMD) patients, levels of matrix metalloproteinase-9 (MMP-9), tissue inhibitors of metalloproteinase-1 (TIMP-1) and osteopontin (OPN) were determined in 63 DMD patients on corticosteroid therapy. These proteins were selected for their role in the pathogenesis of muscular dystrophy. Levels of MMP-9 and TIMP-1 were significantly higher in sera of DMD patients compared to healthy controls, whereas the OPN levels showed no significant difference. MMP-9 levels were also observed to be significantly higher in older, nonambulant patients, compared to ambulant patients. Longitudinal data from a smaller cohort of DMD patients followed up for over 4years showed that MMP-9, but not TIMP-1 increased significantly with age. Hence, MMP-9 is a potential DMD biomarker for disease progression. Future studies have to confirm whether serum MMP-9 levels can be used to monitor therapeutic response. PMID:21724396
Nadarajah, V D; van Putten, M; Chaouch, A; Garrood, P; Straub, V; Lochmüller, H; Ginjaar, H B; Aartsma-Rus, A M; van Ommen, G J B; den Dunnen, J T; 't Hoen, P A C
Fukutin-related protein (FKRP) is a putative glycosyltransferase that mediate O-linked glycosylation of the ?-dystroglycan. Mutations in the FKRP gene cause a spectrum of diseases ranging from a limb girdle muscular dystrophy 2I (LGMD2I), to severe Walker-Warburg or muscle-eye-brain forms and a congenital muscular dystrophy (with or without mental retardation) termed MDC1C. This article reports on a Moroccan infant who presented at birth with moderate floppiness, high serum creatine kinase (CK) levels, and brain ultrasonograph suggestive of widening of the posterior fossa. Muscle biopsy displayed moderate dystrophic pattern with complete absence of ?-distroglycan and genetic studies identified a homozygous missense variant in FKRP. Mutations in FKRP should be looked for in forms of neonatal-onset hyperCKaemia with floppiness and small cerebellum. PMID:23420653
Trovato, Rosanna; Astrea, Guja; Bartalena, Laura; Ghirri, Paolo; Baldacci, Jacopo; Giampietri, Matteo; Battini, Roberta; Santorelli, Filippo M; Fiorillo, Chiara
Ullrich congenital muscular dystrophy (UCMD) is characterized by congenital weakness, proximal joint contractures, and hyperlaxity of distal joints. UCMD is basically due to a defect in extra cellular matrix protein, collagen type VI. A 37-year-old woman who cannot walk independently visited our outpatient clinic. She had orthopedic deformities (scoliosis, joint contractures, and distal joint hyperlaxity), difficulty of respiration, and many skin keloids. Her hip computed tomography showed diffuse fatty infiltration and the 'central shadow' sign in thigh muscles. From the clinical information suggesting collagen type VI related muscle disorder, UCMD was highly considered. COL6A1 gene sequencing confirmed this patient as UCMD with novel c.904G>A (p.Gly302Arg) variant. If musculoskeletal and dermatologic manifestations and radiologic findings imply abnormalities in collagen type VI network, COL6A related congenital muscular dystrophy was to be suspected. PMID:24855628
Park, Yoonhong; Park, Myung Seok; Sung, Duk Hyun; Sohn, Ji Yeon; Ki, Chang-Seok; Kim, Du-Hwan
Ullrich congenital muscular dystrophy (UCMD) is characterized by congenital weakness, proximal joint contractures, and hyperlaxity of distal joints. UCMD is basically due to a defect in extra cellular matrix protein, collagen type VI. A 37-year-old woman who cannot walk independently visited our outpatient clinic. She had orthopedic deformities (scoliosis, joint contractures, and distal joint hyperlaxity), difficulty of respiration, and many skin keloids. Her hip computed tomography showed diffuse fatty infiltration and the 'central shadow' sign in thigh muscles. From the clinical information suggesting collagen type VI related muscle disorder, UCMD was highly considered. COL6A1 gene sequencing confirmed this patient as UCMD with novel c.904G>A (p.Gly302Arg) variant. If musculoskeletal and dermatologic manifestations and radiologic findings imply abnormalities in collagen type VI network, COL6A related congenital muscular dystrophy was to be suspected.
Park, Yoonhong; Park, Myung Seok; Sohn, Ji Yeon; Ki, Chang-Seok; Kim, Du-Hwan
A heterogeneous group of patients with congenital muscular dystrophy associated with clinical or radiologic central nervous system involvement other than the severe classic form with merosin deficiency, muscle-eye-brain disease, and Walker-Warburg syndrome is described. A probable hereditary or familial occurrence could be suggested in all patients. One merosin-positive patient presented severe motor incapacity and cerebral atrophy without any clinical manifestation
Umbertina C. Reed; Suely K. Nagahashi Marie; Mariz Vainzof; Lucio F. Gobbo; Juliana E. P. Gurgel; Mary S. Carvalho; Maria Bernadete D. Resende; Adriana A. Espíndola; Mayana Zatz; Aron Diament
Epidermolysis bullosa simplex with muscular dystrophy (OMIM 226670) is an autosomal recessive disorder caused by mutations of the human plectin gene on chromosome 8q24. Here, we report a 3-year-old girl, offspring of a consanguineous Lebanese family, who presented with skin blistering and recurrent episodes of severe respiratory distress necessitating tracheotomy at the age of 2 years. Repeated examination did not
Ulrike Schara; Jens Tücke; Wilhelm Mortier; Thomas Nüßlein; Fatima Rouan; Ellen Pfendner; Detlef Zillikens; Leena Bruckner-Tuderman; Jouni Uitto; Gerhard Wiche; Rolf Schröder
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal-dominant disorder which has been mapped to the 4q35 region. In order to saturate this distal 4q region with DNA markers, a laser-based chromosomal microdissection and microcloning procedure was used to construct a genomic library from the distal 20% of chromosome 4, derived from a single human metaphase spread. Of the 100 microclones analyzed
M. Upadhyaya; M. Osborn; J. Maynard; M. Altherr; J. Ikeda; P. S. Harper
We evaluated safety and feasibility of the transvenous limb perfusion gene delivery method in muscular dystrophy. A dose escalation study of single limb perfusion with 0.9% saline starting with 5% of limb volume was carried out in adults with muscular dystrophies under intravenous analgesia/anesthesia. Cardiac, vascular, renal, muscle, and nerve functions were monitored. A tourniquet was placed above the knee with inflated pressure of 310 mm Hg. Infusion was carried out with a clinically approved infuser via an intravenous catheter inserted in the saphenous vein with a goal infusion rate of 80 ml/minute. Infusion volume was escalated stepwise to 20% limb volume in seven subjects. No subject complained of any post procedure pain other than due to needle punctures. Safety warning boundaries were exceeded only for transient depression of limb tissue oximetry and transient elevation of muscle compartment pressures; these were not associated with nerve, muscle, or vascular damage. Muscle magnetic resonant imaging (MRI) demonstrated fluid accumulation in muscles of the perfused lower extremity. High-pressure retrograde transvenous limb perfusion with saline up to 20% of limb volume at above infusion parameters is safe and feasible in adult human muscular dystrophy. This study will serve as a basis for future gene transfer clinical trials.
Fan, Zheng; Kocis, Keith; Valley, Robert; Howard, James F; Chopra, Manisha; An, Hongyu; Lin, Weili; Muenzer, Joseph; Powers, William
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant myopathy with a strong epigenetic component. It is associated with deletion of a macrosatellite repeat leading to over-expression of the nearby genes. Among them, we focused on FSHD region gene 1 (FRG1) since its over-expression in mice, Xenopus laevis and Caenorhabditis elegans, leads to muscular dystrophy-like defects, suggesting that FRG1 plays a relevant role in muscle biology. Here we show that, when over-expressed, FRG1 binds and interferes with the activity of the histone methyltransferase Suv4-20h1 both in mammals and Drosophila. Accordingly, FRG1 over-expression or Suv4-20h1 knockdown inhibits myogenesis. Moreover, Suv4-20h KO mice develop muscular dystrophy signs. Finally, we identify the FRG1/Suv4-20h1 target Eid3 as a novel myogenic inhibitor that contributes to the muscle differentiation defects. Our study suggests a novel role of FRG1 as epigenetic regulator of muscle differentiation and indicates that Suv4-20h1 has a gene-specific function in myogenesis. PMID:23720823
Neguembor, Maria Victoria; Xynos, Alexandros; Onorati, Maria Cristina; Caccia, Roberta; Bortolanza, Sergia; Godio, Cristina; Pistoni, Mariaelena; Corona, Davide F; Schotta, Gunnar; Gabellini, Davide
In 2005, the American Academy of Neurology and the Child Neurology Society published a practice parameter, based primarily on studies that involved 6 to 18 months of treatment, indicating that prednisone has a beneficial effect on muscle strength and function in patients with Duchenne muscular dystrophy and recommended that corticosteroids be offered (prednisone 0.75 mg/kg/d and deflazacort 0.9 mg/kg/d) as treatment. Recent reports emphasize that longer term treatment with corticosteroids (greater than 3 years) produces important sustained benefits in neuromuscular function without causing major side effects. This review highlights these reports and indicates that long-term corticosteroid therapy (1) prolongs ambulation by 2 to 5 years, (2) reduces the need for spinal stabilization surgery, (3) improves cardiopulmonary function, (4) delays the need for noninvasive nasal ventilation, and (5) increases survival and the quality of life of patients with Duchenne muscular dystrophy. Educational, vocational, and other social counseling is now a vital part of management for Duchenne muscular dystrophy. PMID:20581335
Moxley, Richard T; Pandya, Shree; Ciafaloni, Emma; Fox, Deborah J; Campbell, Kim
Limb-girdle muscular dystrophy 2B, Miyoshi myopathy, and distal myopathy of anterior tibialis are severely debilitating muscular dystrophies caused by genetically determined dysferlin deficiency. In these muscular dystrophies, it is the repair, not the structure, of the plasma membrane that is impaired. Though much is known about the effects of dysferlin deficiency in skeletal muscle, little is known about the role of dysferlin in maintenance of cardiomyocytes. Recent evidence suggests that dysferlin deficiency affects cardiac muscle, leading to cardiomyopathy when stressed. However, neither the morphological location of dysferlin in the cardiomyocyte nor the progression of the disease with age are known. In this study, we examined a mouse model of dysferlinopathy using light and electron microscopy as well as echocardiography and conscious electrocardiography. We determined that dysferlin is normally localized to the intercalated disk and sarcoplasm of the cardiomyocytes. In the absence of dysferlin, cardiomyocyte membrane damage occurs and is localized to the intercalated disk and sarcoplasm. This damage results in transient functional deficits at 10 months of age, but, unlike in skeletal muscle, the cell injury is sublethal and causes only mild cardiomyopathy even at advanced ages.
Chase, Thomas H.; Cox, Gregory A.; Burzenski, Lisa; Foreman, Oded; Shultz, Leonard D.
The role of angiotensin-converting enzyme inhibitors in the management of cardiomyopathy related to Duchenne muscular dystrophy has not been completely defined. The purposes of this study were to describe the response to enalapril and its relation to dystrophin mutation type, ventricular size, or age at the onset of left ventricular (LV) systolic dysfunction. Serial clinical and echocardiographic data from 50 patients with Duchenne muscular dystrophy (aged 10 to 20 years) were retrospectively reviewed. Twenty-seven patients (46%) developed LV systolic dysfunction (mean age 13.2 +/- 2.4 years). Ten (43%) responded to enalapril with the normalization of function. Responders and nonresponders developed LV systolic dysfunction at similar ages (p = 0.91). At the onset of LV systolic dysfunction, only 2 patients (1 responder, 1 nonresponder) had dilated left ventricles. The positive response to enalapril was sustained in 7 patients (median follow-up 23 months, range 5 to 58). No specific mutation was associated with the response to enalapril (p = 0.66) or predictive of the development of LV systolic dysfunction (p = 0.8). In conclusion, 10 of 26 patients (43%) with Duchenne muscular dystrophy responded to the use of enalapril with normalization of the shortening fraction. Age at the onset of LV systolic dysfunction and the type of mutation were not predictors of response to enalapril. PMID:16950195
Ramaciotti, Claudio; Heistein, Lisa C; Coursey, Melanie; Lemler, Matthew S; Eapen, Reenu S; Iannaccone, Susan T; Scott, William A
Background Recent methodological advances have improved the detection rate for dystrophin mutations, but there are no published studies that have measured the clinical utility of these protocols for carrier detection compared with conventional carrier testing protocols that use pedigree, serum creatine kinase levels and linkage analysis. Methods and subjects The clinical utility of a combined mutation detection protocol was measured. It involved quantitative PCR procedures followed by DNA sequence analysis for the identification of dystrophin mutation carriers in 2101 women at risk of being carriers from 348 mutation?known Duchenne or Becker muscular dystrophy pedigrees. Results The combined mutation detection protocol identified a mutation in 96% and 82% of index cases of Duchenne muscular dystrophy and Becker muscular dystrophy, respectively. An additional 692 (33%) potential carriers were correctly classified by the combined mutation detection protocol compared with pedigree, serum creatine kinase levels and linkage analysis. Significantly lower mutation carrier rates were identified in the mothers of isolated cases with deletion mutations than predicted from theoretical considerations, but these findings were not confirmed for duplication and DNA sequence mutations. Conclusions There are significant clinical benefits to be gained from a combined mutation detection protocol for carrier detection. It is recommended that mutation?specific carrier frequencies for the different classes of dystrophin mutations should be taken into account in genetic counselling practice.
Taylor, Peter J; Maroulis, Sarah; Mullan, Glenda L; Pedersen, Robyn L; Baumli, Aurora; Elakis, George; Piras, Sara; Walsh, Corrina; Prosper-Gutierrez, Benito; De La Puente-Alonso, Fernando; Bell, Christopher G; Mowat, David R; Johnston, Heather M; Buckley, Michael F
There have been reports of abnormal retinal neurotransmission determined by electroretinography in boys with Duchenne and Becker muscular dystrophy. Dystrophin may play a role in transmitting signals between photoreceptors and the excitatory synapse of the ON-bipolar cell. These electroretinographic changes appeared to be limited to the rod ON-pathway but we felt there was also similar abnormality in the cone ON-pathway. We used long-duration stimuli to separate ON-(depolarizing bipolar cell) and OFF (hyperpolarizing bipolar cell) contributions to the cone-dominated ERG to better understand how the retina functions in boys with Duchenne muscular dystrophy. We recorded the electroretinograms of 11 boys with Duchenne muscular dystrophy and found abnormal signal transmission at the level of the photoreceptor and ON-bipolar cell in both the rod and cone generated responses. The OFF-bipolar cell that responds to the offset of the stimulus continues to function normally. The results support our hypothesis that retinal dystrophin plays a role in receptor function or controlling ion channels at the level of the photoreceptor and depolarizing bipolar cell.
Fitzgerald, K M; Cibis, G W; Giambrone, S A; Harris, D J
Facioscapulohumeral muscular dystrophy (FSHD), the most frequent muscular dystrophy, is an autosomal dominant disease. In most individuals with FSHD, symptoms are restricted to muscles of the face, arms, legs, and trunk. FSHD is genetically linked to contractions of the D4Z4 repeat array causing activation of several genes. One of these maps in the repeat itself and expresses the DUX4 (the double homeobox 4) transcription factor causing a gene deregulation cascade. In addition, analyses of the RNA or protein expression profiles in muscle have indicated deregulations in the oxidative stress response. Since oxidative stress affects peripheral muscle function, we investigated mitochondrial function and oxidative stress in skeletal muscle biopsies and blood samples from patients with FSHD and age-matched healthy controls, and evaluated their association with physical performances. We show that specifically, oxidative stress (lipid peroxidation and protein carbonylation), oxidative damage (lipofuscin accumulation), and antioxidant enzymes (catalase, copper-zinc-dependent superoxide dismutase, and glutathione reductase) were higher in FSHD than in control muscles. FSHD muscles also presented abnormal mitochondrial function (decreased cytochrome c oxidase activity and reduced ATP synthesis). In addition, the ratio between reduced (GSH) and oxidized glutathione (GSSG) was strongly decreased in all FSHD blood samples as a consequence of GSSG accumulation. Patients with FSHD also had reduced systemic antioxidative response molecules, such as low levels of zinc (a SOD cofactor), selenium (a GPx cofactor involved in the elimination of lipid peroxides), and vitamin C. Half of them had a low ratio of gamma/alpha tocopherol and higher ferritin concentrations. Both systemic oxidative stress and mitochondrial dysfunction were correlated with functional muscle impairment. Mitochondrial ATP production was significantly correlated with both quadriceps endurance (T(LimQ)) and maximal voluntary contraction (MVC(Q)) values (rho=0.79, P=0.003; rho=0.62, P=0.05, respectively). The plasma concentration of oxidized glutathione was negatively correlated with the T(LimQ), MVC(Q) values, and the 2-min walk distance (MWT) values (rho=-0.60, P=0.03; rho=-0.56, P=0.04; rho=-0.93, P<0.0001, respectively). Our data characterized oxidative stress in patients with FSHD and demonstrated a correlation with their peripheral skeletal muscle dysfunction. They suggest that antioxidants that might modulate or delay oxidative insult may be useful in maintaining FSHD muscle functions. PMID:22796148
Turki, Ahmed; Hayot, Maurice; Carnac, Gilles; Pillard, Fabien; Passerieux, Emilie; Bommart, Sébastien; Raynaud de Mauverger, Eric; Hugon, Gérald; Pincemail, Joel; Pietri, Sylvia; Lambert, Karen; Belayew, Alexandra; Vassetzky, Yegor; Juntas Morales, Raul; Mercier, Jacques; Laoudj-Chenivesse, Dalila
Purification of the proteins associated with dystrophin, the gene product responsible for Duchenne muscular dystrophy, led to the discovery of the dystrophin-glycoprotein complex. Sarcospan, a 25-kDa transmembrane protein, was the last component to be identified and its function in skeletal muscle has been elusive. This review will focus on progress over the last decade revealing that sarcospan is an important regulator of muscle cell adhesion, strength, and regeneration. Investigations using several transgenic mouse models demonstrate that overexpression of sarcospan in the mouse model for Duchenne muscular dystrophy ameliorates pathology and restores muscle cell binding to laminin. Sarcospan improves cell surface expression of the dystrophin- and utrophin-glycoprotein complexes as well as ?7?1 integrin, which are the three major laminin-binding complexes in muscle. Utrophin and ?7?1 integrin compensate for the loss of dystrophin and the finding that sarcospan increases their abundance at the extra-synaptic sarcolemma supports the use of sarcospan as a therapeutic target. Newly discovered phenotypes in sarcospan-deficient mice, including a reduction in specific force output and increased drop in force in the diaphragm muscle, result from decreased utrophin and dystrophin expression and further reveal sarcospan's role in determining abundance of these complexes. Dystrophin protein levels and the specific force output of the diaphragm muscle are further reduced upon genetic removal of ?7 integrin (Itga7) in SSPN-deficient mice, demonstrating that interactions between integrin and sarcospan are critical for maintenance of the dystrophin-glycoprotein complex and force production of the diaphragm muscle. Sarcospan is a major regulator of Akt signaling pathways and sarcospan-deficiency significantly impairs muscle regeneration, a process that is dependent on Akt activation. Intriguingly, sarcospan regulates glycosylation of a specific subpopulation of ?-dystroglycan, the laminin-binding receptor associated with dystrophin and utrophin, localized to the neuromuscular junction. Understanding the basic mechanisms responsible for assembly and trafficking of the dystrophin- and utrophin-glycoprotein complexes to the cell surface is lacking and recent studies suggest that sarcospan plays a role in these essential processes. PMID:23282144
Marshall, Jamie L; Crosbie-Watson, Rachelle H
Duchenne muscular dystrophy (DMD) typically occurs as a result of truncating mutations in the DMD gene that result in a lack of expression of the dystrophin protein in muscle fibers. Various therapies under development are directed toward restoring dystrophin expression at the subsarcolemmal membrane, including gene transfer. In a trial of intramuscular adeno-associated virus (AAV)-mediated delivery of a therapeutic minidystrophin construct, we identified in two of six subjects the presence of a population of T cells that had been primed to recognize dystrophin epitopes before transgene delivery. As the presence of preexisting T cell immunity may have a significant effect on the success of therapeutic approaches for restoring dystrophin, we sought to determine the prevalence of such immunity within a DMD cohort from our Muscular Dystrophy Association clinic. Dystrophin-specific T cell immunity was evaluated in subjects with DMD who were either receiving the glucocorticoid steroid prednisone (n=24) or deflazacort (n=29), or who were not receiving steroids (n=17), as well as from normal age-matched control subjects (n=21). We demonstrate that increasing age correlates with an increased risk for the presence of anti-dystrophin T cell immunity, and that treatment with either corticosteroid decreases risk compared with no treatment, suggesting that steroid therapy in part may derive some of its benefit through modulation of T cell responses. The frequency of dystrophin-specific T cells detected by enzyme-linked immunospot assay was lower in subjects treated with deflazacort versus prednisone, despite similar overall corticosteroid exposure, suggesting that the effects of the two corticosteroids may not be identical in patients with DMD. T cells targeted epitopes upstream and downstream of the dystrophin gene mutation and involved the CD4? helper and/or CD8? cytotoxic subsets. Our data confirm the presence of preexisting circulating T cell immunity to dystrophin in a sizable proportion of patients with DMD, and emphasize the need to consider this in the design and interpretation of clinical gene therapy trials. PMID:24010700
Flanigan, Kevin M; Campbell, Katie; Viollet, Laurence; Wang, Wei; Gomez, Ana Maria; Walker, Christopher M; Mendell, Jerry R
Facioscapulohumeral muscular dystrophy has been genetically linked to reduced numbers (?8) of D4Z4 repeats at 4q35 combined with 4A(159/161/168) DUX4 polyadenylation signal haplotype. However, we have recently reported that 1.3% of healthy individuals carry this molecular signature and 19% of subjects affected by facioscapulohumeral muscular dystrophy do not carry alleles with eight or fewer D4Z4 repeats. Therefore, prognosis for subjects carrying or at risk of carrying D4Z4 reduced alleles has become more complicated. To test for additional prognostic factors, we measured the degree of motor impairment in a large group of patients affected by facioscapulohumeral muscular dystrophy and their relatives who are carrying D4Z4 reduced alleles. The clinical expression of motor impairment was assessed in 530 subjects, 163 probands and 367 relatives, from 176 unrelated families according to a standardized clinical score. The associations between clinical severity and size of D4Z4 allele, degree of kinship, gender, age and 4q haplotype were evaluated. Overall, 32.2% of relatives did not display any muscle functional impairment. This phenotype was influenced by the degree of relation with proband, because 47.1% of second- through fifth-degree relatives were unaffected, whereas only 27.5% of first-degree family members did not show motor impairment. The estimated risk of developing motor impairment by age 50 for relatives carrying a D4Z4 reduced allele with 1–3 repeats or 4–8 repeats was 88.7% and 55%, respectively. Male relatives had a mean score significantly higher than females (5.4 versus 4.0, P = 0.003). No 4q haplotype was exclusively associated with the presence of disease. In 13% of families in which D4Z4 alleles with 4–8 repeats segregate, the diagnosis of facioscapulohumeral muscular dystrophy was reported only in one generation. In conclusion, this large-scale analysis provides further information that should be taken into account when counselling families in which a reduced allele with 4–8 D4Z4 repeats segregates. In addition, the reduced expression of disease observed in distant relatives suggests that a family’s genetic background plays a role in the occurrence of facioscapulohumeral muscular dystrophy. These results indicate that the identification of new susceptibility factors for this disease will require an accurate classification of families.
Scionti, Isabella; Sera, Francesco; Govi, Monica; D'Amico, Roberto; Frambolli, Ilaria; Mele, Fabiano; Filosto, Massimiliano; Vercelli, Liliana; Ruggiero, Lucia; Berardinelli, Angela; Angelini, Corrado; Antonini, Giovanni; Bucci, Elisabetta; Cao, Michelangelo; Daolio, Jessica; Di Muzio, Antonio; Di Leo, Rita; Galluzzi, Giuliana; Iannaccone, Elisabetta; Maggi, Lorenzo; Maruotti, Valerio; Moggio, Maurizio; Mongini, Tiziana; Morandi, Lucia; Nikolic, Ana; Pastorello, Ebe; Ricci, Enzo; Rodolico, Carmelo; Santoro, Lucio; Servida, Maura; Siciliano, Gabriele; Tomelleri, Giuliano
Ullrich congenital muscular dystrophy (UCMD) is an autosomal recessive disorder characterized by generalized muscular weakness, contractures of multiple joints, and distal hyperextensibility. Homozygous and compound heterozygous mutations of COL6A2 on chromosome 21q22 have recently been shown to cause UCMD. We performed a genomewide screening with microsatellite markers in a consanguineous family with three sibs affected with UCMD. Linkage of the disease to chromosome 2q37 was found in this family and in two others. We analyzed COL6A3, which encodes the ?3 chain of collagen VI, and identified one homozygous mutation per family. In family I, the three sibs carried an A?G transition in the splice-donor site of intron 29 (6930+5A?G), leading to the skipping of exon 29, a partial reduction of collagen VI in muscle biopsy, and an intermediate phenotype. In family II, the patient had an unusual mild phenotype, despite a nonsense mutation, R465X, in exon 5. Analysis of the patient’s COL6A3 transcripts showed the presence of various mRNA species—one of which lacked several exons, including the exon containing the nonsense mutation. The deleted splice variant encodes collagen molecules that have a shorter N-terminal domain but that may assemble with other chains and retain a functional role. This could explain the mild phenotype of the patient who was still ambulant at age 18 years and who showed an unusual combination of hyperlaxity and finger contractures. In family III, the patient had a nonsense mutation, R2342X, causing absence of collagen VI in muscle and fibroblasts, and a severe phenotype, as has been described in patients with UCMD. Mutations in COL6A3 are described in UCMD for the first time and illustrate the wide spectrum of phenotypes which can be caused by collagen VI deficiency.
Demir, Ercan; Sabatelli, Patrizia; Allamand, Valerie; Ferreiro, Ana; Moghadaszadeh, Behzad; Makrelouf, Mohamed; Topaloglu, Haluk; Echenne, Bernard; Merlini, Luciano; Guicheney, Pascale
The dystrophin-deficient dog is excellent large animal model for testing novel therapeutic modalities for Duchenne muscular dystrophy (DMD). Despite well-documented descriptions of dystrophic symptoms in these dogs, very few quantitative studies have been performed. Here, we developed a comprehensive set of non-invasive assays to quantify dog gait (stride length and speed), joint angle and limb mobility (for both forelimb and hind limb), and spontaneous activity at night. To validate these assays, we examined three 8-m-old mix-breed dystrophic dogs. We also included three age-matched siblings as the normal control. High-resolution video recorders were used to digitize dog walking and spontaneous movement at night. Stride speed and length were significantly decreased in affected dogs. The mobility of the limb segments (forearm, front foot, lower thigh, rear foot) and the carpus and hock joints was significantly reduced in dystrophic dogs. There was also a significant reduction of the movement in affected dogs during overnight monitoring. In summary, we have established a comprehensive set of outcome measures for clinical phenotyping of DMD dogs. These non-invasive end points would be valuable in monitoring disease progression and therapeutic efficacy in translational studies in the DMD dog model. PMID:23544107
Shin, Jin-Hong; Greer, Brian; Hakim, Chady H; Zhou, Zhongna; Chung, Yu-chia; Duan, Ye; He, Zhihai; Duan, Dongsheng
To construct biologically interpretable gene sets for muscular dystrophy (MD) sub-type classification, we propose a novel computational scheme to integrate protein-protein interaction (PPI) network, functional gene set information, and mRNA profiling data. The workflow of the proposed scheme includes the following three major steps: firstly, we apply an affinity propagation clustering (APC) approach to identify gene sub-networks associated with each MD sub-type, in which a new distance metric is proposed for APC to combine PPI network information and gene-gene co-expression relationship; secondly, we further incorporate functional gene set knowledge, which complements the physical PPI information, into our scheme for biomarker identification; finally, based on the constructed sub-networks and gene set features, we apply multi-class support vector machines (MSVMs) for MD sub-type classification, with which to highlight the biomarkers contributing to sub-type prediction. The experimental results show that our scheme can help identify sub-networks and gene sets that are more relevant to MD than those constructed by other conventional approaches. Moreover, our integrative strategy improves the prediction accuracy substantially, especially for those 'hard-to-classify' sub-types. PMID:22773895
Wang, Chen; Ha, Sook; Xuan, Jianhua; Wang, Yue; Hoffman, Eric
To construct biologically interpretable gene sets for muscular dystrophy (MD) sub-type classification, we propose a novel computational scheme to integrate protein-protein interaction (PPI) network, functional gene set information, and mRNA profiling data. The workflow of the proposed scheme includes the following three major steps: firstly, we apply an affinity propagation clustering (APC) approach to identify gene sub-networks associated with each MD sub-type, in which a new distance metric is proposed for APC to combine PPI network information and gene-gene co-expression relationship; secondly, we further incorporate functional gene set knowledge, which complements the physical PPI information, into our scheme for biomarker identification; finally, based on the constructed sub-networks and gene set features, we apply multi-class support vector machines (MSVMs) for MD sub-type classification, with which to highlight the biomarkers contributing to sub-type prediction. The experimental results show that our scheme can help identify sub-networks and gene sets that are more relevant to MD than those constructed by other conventional approaches. Moreover, our integrative strategy improves the prediction accuracy substantially, especially for those ’hard-to-classify’ sub-types.
Wang, Chen; Ha, Sook; Wang, Yue; Hoffman, Eric
The purpose of this study was to investigate how age at and value of the plateau of vital capacity (VC plateau) correlate with the severity of the progression of spinal deformity in patients with Duchenne muscular dystrophy (DMD). Changes in spinal deformity and pulmonary function in 36 DMD patients were examined in a retrospective longitudinal study. Patterns of progression of spinal deformity were classified into three types according to Oda's classification. Of the 32 patients who showed spinal deformity, six were classified as type 1, 19 as type 2, and seven as type 3. The correlation between the patterns of progression of spinal deformity and the VC plateau was examined using a discriminant analysis. Rapid and severe progression of spinal deformity could be expected in patients whose VC plateau was less than 1,900 mL and in those in which it occurred before age 14 years. Thus VC plateau may be an indicator of the severity of the progression of spinal deformity in DMD patients. PMID:11176364
Yamashita, T; Kanaya, K; Yokogushi, K; Ishikawa, Y; Minami, R
Facioscapulohumeral muscular dystrophy (FSHD) is an inherited disease, and although strongly suggested, a contribution of inflammation to its pathogenesis has never been demonstrated. In FSHD patients, we found by immunohistochemistry inflammatory infiltrates mainly composed by CD8(+) T cells in muscles showing hyperintensity features on T2-weighted short tau inversion recovery magnetic resonance imaging (T2-STIR-MRI) sequences. Therefore, we evaluated the presence of circulating activated immune cells and the production of cytokines in patients with or without muscles showing hyperintensity features on T2-STIR-MRI sequences and from controls. FSHD patients displaying hyperintensity features in one or more muscles showed higher CD8(+)pSTAT1(+), CD8(+)T-bet(+) T cells and CD14(+)pSTAT1(+), CD14(+)T-bet(+) cells percentages and IL12p40, IFN? and TNF? levels than patients without muscles displaying hyperintense features and controls. Moreover, the percentages of CD8(+)pSTAT1(+), CD8(+)T-bet(+) and CD14(+)pSTAT1(+) cells correlated with the proportion of muscles displaying hyperintensity features at T2-STIR sequences. These data indicate that circulating activated immune cells, mainly CD8(+) T cells, may favour FSHD progression by promoting active phases of muscle inflammation. PMID:21063901
Frisullo, Giovanni; Frusciante, Roberto; Nociti, Viviana; Tasca, Giorgio; Renna, Rosaria; Iorio, Raffaele; Patanella, Agata Katia; Iannaccone, Elisabetta; Marti, Alessandro; Rossi, Monica; Bianco, Assunta; Monforte, Mauro; Tonali, Pietro Attilio; Mirabella, Massimiliano; Batocchi, Anna Paola; Ricci, Enzo
Various characteristics of adeno-associated virus (AAV)-based vectors with long-term safe expression have made it an exciting transduction tool for clinical gene therapy of Duchenne muscular dystrophy (DMD). Although host immune reactions against the vector as well as transgene products were detected in some instances of the clinical studies, there have been promising observations. Methods of producing AAV vectors for considerable in vivo experimentation and clinical investigations have been developed and a number of studies with AAV vector-mediated muscle transduction were attempted. Notably, an intravenous limb perfusion transduction technique enables extensive transgene expression in the skeletal muscles without noticeable adverse events. Furthermore, cardiac transduction by the rAAV9-microdystrophin would be promising to prevent development of cardiac dysfunction. Recent achievements in transduction technology suggest that long-term transgene expression with therapeutic benefits in DMD treatment would be achieved by the rAAV-mediated transduction strategy with an adequate regimen to regulate host immune response.
Okada, Takashi; Takeda, Shin'ichi
Facioscapulohumeral muscular dystrophy (FSHD) is associated with the deletion of a variable number of 3.3-kb subunits of a tandemly arranged repeat (D4Z4) on chromosome 4q35. EcoRI/BlnI fragments in the range of 10-35 kb are currently defined as disease-associated. Diagnosis of FSHD is frequently complicated by interchromosomal exchange with a homologous locus on 10q26. We present clinical and laboratory data of six subjects from two unrelated families with a marked FSHD phenotype and EcoRI/BlnI fragments of 39 and 33 kb, respectively. Origin on chromosome 4q35 was confirmed by haplotype analysis in the first family and was supported by pulsed field gel electrophoresis data in the second family. Our data further confirm the existence of a region of overlap of normal and pathological fragments. Fragments from this region can obviously be associated with marked FSHD phenotypes. Furthermore, application of linked markers and resolution of all EcoRI/BlnI fragments by pulsed field gel electrophoresis in addition to routine laboratory tests considerably augments the information obtained from molecular tests, upon which genetic counselling can then be based. PMID:11932972
Vielhaber, Stefan; Jakubiczka, Sibylle; Schröder, J Michael; Sailer, Michael; Feistner, Helmut; Heinze, Hans-Jochen; Wieacker, Peter; Bettecken, Thomas
Objective: To perform a double-blind, randomized study comparing efficacy and safety of daily and weekend prednisone in boys with Duchenne muscular dystrophy (DMD). Methods: A total of 64 boys with DMD who were between 4 and 10 years of age were randomized at 1 of 12 centers of the Cooperative International Neuromuscular Research Group. Efficacy and safety of 2 prednisone schedules (daily 0.75 mg/kg/day and weekend 10 mg/kg/wk) were evaluated over 12 months. Results: Equivalence was met for weekend and daily dosing of prednisone for the primary outcomes of quantitative muscle testing (QMT) arm score and QMT leg score. Secondary strength scores for QMT elbow flexors also showed equivalence between the 2 treatment groups. Overall side effect profiles of height and weight, bone density, cataract formation, blood pressure, and behavior, analyzed at 12 months, did not differ between weekend and daily dosing of prednisone. Conclusions: Weekend dosing of prednisone is equally beneficial to the standard daily dosing of prednisone. Analysis of side effect profiles demonstrated overall tolerability of both dosing regimens. Classification of evidence: This study provides Class I evidence that weekend prednisone dosing is as safe and effective as daily prednisone in preserving muscle strength and preventing body mass index increases in boys with DMD over a 12-month period.
Hache, L.P.; Clemens, P.R.; Cnaan, A.; McDonald, C.M.; Viswanathan, V.; Kornberg, A.J.; Bertorini, T.E.; Nevo, Y.; Lotze, T.; Pestronk, A.; Ryan, M.M.; Monasterio, E.; Day, J.W.; Zimmerman, A.; Arrieta, A.; Henricson, E.; Mayhew, J.; Florence, J.; Hu, F.; Connolly, A.M.
The purpose of this ethics approved trial was to correlate quantitative MRI with functional abilities in both ambulant and non-ambulant Duchenne muscular dystrophy (DMD). Twenty patients with genetically confirmed DMD were recruited. Physical assessment was performed using the motor function measurement (MFM) scale. Axial 3T MRI scans of the thighs were acquired using T1-weighted in- and opposed-phase images (TR = 20 ms, TE1 = 2.45 ms, TE2 = 3.68 ms, flip angle = 15°) to calculate the relative fat fraction according to the two-point Dixon method in the knee extensors, flexors, and adductor muscles. The average MFM was 65.3 % and correlated negatively to age (r (2) = 0.60). Overall mean fat fraction correlated positively to age (r (2) = 0.51-0.64). An average of 5 % increase in mean fat fraction per year was calculated. Mean fat fraction of the quadriceps showed a high negative correlation (r (2) = 0.93) to the D1 (standing position and transfers) component of the MFM. A cutoff for mean fat fraction of 50 % predicted loss of ambulation with a sensitivity of 100 % and a specificity of 91 %. Therefore, quantitative muscle MRI seems to be a promising endpoint for short clinical trials evaluating the effect of newer treatments on the time of loss of ambulation in DMD. PMID:23138982
Fischmann, Arne; Hafner, Patricia; Gloor, Monika; Schmid, Maurice; Klein, Andrea; Pohlman, Urs; Waltz, Tanja; Gonzalez, Rocio; Haas, Tanja; Bieri, Oliver; Fischer, Dirk
We previously conducted a proof of principle; dose escalation study in Duchenne muscular dystrophy (DMD) patients using the morpholino splice-switching oligonucleotide AVI-4658 (eteplirsen) that induces skipping of dystrophin exon 51 in patients with relevant deletions, restores the open reading frame and induces dystrophin protein expression after intramuscular (i.m.) injection. We now show that this dystrophin expression was accompanied by an elevated expression of ?-sarcoglycan, ?-dystroglycan (BDG) and—in relevant cases—neuronal nitric oxide synthase (nNOS) at the sarcolemma, each of which is a component of a different subcomplex of the dystrophin-associated glycoprotein complex (DAPC). As expected, nNOS expression was relocalized to the sarcolemma in Duchenne patients in whom the dystrophin deletion left the nNOS-binding domain (exons 42–45) intact, whereas this did not occur in patients with deletions that involved this domain. Our results indicate that the novel internally deleted and shorter dystrophin induced by skipping exon 51 in patients with amenable deletions, can also restore the dystrophin-associated complex, further suggesting preserved functionality of the newly translated dystrophin.
Cirak, Sebahattin; Feng, Lucy; Anthony, Karen; Arechavala-Gomeza, Virginia; Torelli, Silvia; Sewry, Caroline; Morgan, Jennifer E; Muntoni, Francesco
Duchenne and Becker muscular dystrophy (DMD and BMD) are caused, in the majority of cases, by deletions in the dystrophin gene (DMD). The disease is an X-linked neuromuscular diseases typically caused by disrupting (DMD) or non-disrupting (BMD) the reading frame in the dystrophin (DMD) gene. In the present study, amplifications of the genomic DNAs of unrelated 15 Saudi DMD males were carried out using multiplex polymerase chain reaction (PCR) for nine-hotspot regions of exons 4, 8, 12, 17, 19, 44, 45, 48 and 51. We detected six Saudi patients having deletions in a frequency of 40%. The frequency of deletions in exon 51 (20%) was the most common deletion frequently associated with our Saudi sample males. Exons 19, 45, and 48 were present in a frequency of 6.7% each. All deletions were recognized as an individual exonic deletions, while no gross deletion where detected. Finally, the molecular deletions in the Saudi males was expected to be characterized by a moderate frequency among different populations due to the geographical KSA region, which it is in the crossroad of intense migrations and admixture of people coming from continental Asia, Africa, and even Europe. In conclusion, attempts to include an extra DNA samples might reflect a valid vision of the deletions within the high frequency deletion regions (HFDR’s) in the DMD gene mutations in KSA.
Tayeb, Mohammed T.
Corticosteroids are effective in improving motor function in Duchenne muscular dystrophy (DMD) patients within 6 months-2 years of treatment initiation, but there is as yet no consensus on which treatment scheme is the best. We retrospectively analyzed data of 35 DMD patients who were treated with prednisone 0.75 mg/kg per day intermittently 10 days on/10 days off. Prednisone was started during the ambulant phase at age 3.5-9.7 years (median 6.5 years). The median period of treatment was 27 months (range 3-123 months). The median age at which ambulation was lost was 10.8 years (mean 10.9 years; 95% confidence interval 10.0-11.8 years). Nine patients (26%) had excessive weight gain. Eight boys (21%) had a bone fracture, which was when four of these eight children lost the ability to walk. Treatment was stopped in two obese patients, two hyperactive boys and one patient following a fracture. Our data suggest that prednisone 10 on/10 off has relatively few side effects and extends the ambulant phase by 1 year compared to historical controls. PMID:19306039
Straathof, Chiara S M; Overweg-Plandsoen, W C G Truus; van den Burg, Gert Jan; van der Kooi, Anneke J; Verschuuren, Jan J G M; de Groot, Imelda J M
In June 2010, 25 representatives from Europe and the US met in Washington, DC, USA, to discuss clinical outcome measures in Duchenne muscular dystrophy (DMD) in the context of clinical trial design and analysis. The workshop was organized in response to a September 2009 European Medicines Agency meeting where a clear directive was given that an international consensus needs to be developed that provides a foundation for age-appropriate clinical outcome measures for use in clinical trials of emerging therapeutics for DMD. Data were presented from eight multicenter longitudinal datasets, representing nearly 1900 patients over a 20-year time period. This experience confirmed the feasibility of repeated evaluations performed at multiple sites and addressed several core issues in drug development for DMD, such as the ‘new’ natural history in the steroidera, reliability and sensitivity of specific outcome measures, as well as disease staging and patient selection. These data form a valuable asset for academic investigators, pharmaceutical sponsors and regulatory agencies involved in DMD therapeutics. The group remains committed working together on a number of collaborative goals to support the therapeutics development effort in this orphan disease and to make these data available to stakeholders working in the field.
Bushby, Kate; Connor, Edward
Background Various prognostic serum and cellular markers have been identified for many diseases, such as cardiovascular diseases and tumor pathologies. Here we assessed whether the levels of certain stem cells may predict the progression of Duchenne muscular dystrophy (DMD). Methods and Findings The levels of several subpopulations of circulating stem cells expressing the CD133 antigen were determined by flow cytometry in 70 DMD patients. The correlation between the levels and clinical status was assessed by statistical analysis. The median (±SD) age of the population was 10.66±3.81 (range 3 to 20 years). The levels of CD133+CXCR4+CD34- stem cells were significantly higher in DMD patients compared to healthy controls (mean±standard deviation: 17.38±1.38 vs. 11.0±1.70; P?=?0.03) with a tendency towards decreased levels in older patients. Moreover, the levels of this subpopulation of cells correlated with the clinical condition. In a subgroup of 19 DMD patients after 24 months of follow-up, increased levels of CD133+CXCR4+CD34- cells was shown to be associated with a phenotype characterised by slower disease progression. The circulating CD133+CXCR4+CD34- cells in patients from different ages did not exhibit significant differences in their myogenic and endothelial in vitro differentiation capacity. Conclusions Our results suggest that levels of CD133+CXCR4+CD34- could function as a new prognostic clinical marker for the progression of DMD.
Marchesi, Chiara; Belicchi, Marzia; Meregalli, Mirella; Farini, Andrea; Cattaneo, Alessandra; Parolini, Daniele; Gavina, Manuela; Porretti, Laura; D'Angelo, Maria Grazia; Bresolin, Nereo; Cossu, Giulio; Torrente, Yvan
Scoliosis affects 75 to 90% of patients with non-ambulant Duchenne muscular dystrophy (DMD). Spinal surgery is the treatment of choice but the indication varies among centres. Some offer surgery to all non-ambulant patients, irrespective of scoliosis severity. Early surgery has the advantage of targeting DMD when cardiorespiratory function is preserved, but not all patients develop scoliosis. We report our 10-year experience of scoliosis management in 123 patients with DMD who were at least 17 years old at the time of the study. Scoliosis was absent in 10%, and mild, non-progressive (at least 30 degrees ) in 13% of patients. Another 13% had moderate scoliosis (31-50 degrees ) and were managed conservatively. Surgery was considered in 57% (70/123) of patients with scoliosis greater than 50 degrees and eventually performed in 35%. The remaining patients either refused surgery (9%) or were unfit because of cardiorespiratory compromise (13%). In a further 7%, scoliosis (greater than 50 degrees ), first noted after 14 years of age, was progressing slowly and surgery was not performed. At 17 years there was no difference in survival, respiratory impairment, or sitting comfort among patients managed conservatively or with surgery. One-third (44/123) of our patients were managed satisfactorily without receiving spinal surgery. We provide insight into the natural history of scoliosis in DMD that should help families and clinicians with decision-making when surgery is considered. PMID:16700946
Kinali, M; Messina, S; Mercuri, E; Lehovsky, J; Edge, G; Manzur, A Y; Muntoni, F
Introduction Corticosteroid treatment slows disease progression and is the standard of care for Duchenne muscular dystrophy (DMD). Coenzyme Q10 (CoQ10) is a potent antioxidant that may improve function in dystrophin deficient muscle. Methods We performed an open label, “add-on” pilot study of CoQ10 in thirteen 5–10 year old DMD patients on steroids. The primary outcome measure was the total Quantitative Muscle Testing (QMT) score. Results Twelve of 16 children (mean age 8.03±1.64 years) completed the trial. Target serum levels of CoQ10 (?2.5 ?g/ml) were shown to be subject- and administration-dependent. Nine of 12 subjects showed an increase in total QMT score. Overall, CoQ10 treatment resulted in 8.5 % increase in muscle strength (p=0.03). Discussion This pilot study found the addition of CoQ10 to prednisone therapy in DMD patients resulted in an increase in muscle strength. These results warrant a larger, controlled trial of CoQ10 in DMD.
Spurney, Christopher F.; Rocha, Carolina Tesi; Henricson, Erik; Florence, Julaine; Mayhew, Jill; Gorni, Ksenija; Pasquali, Livia; Pestronk, Alan; Martin, Gerard R.; Hu, Fengming; Nie, Lei; Connolly, Anne M.; Escolar, Diana M.
Neuromuscular disorders are characterised by progressive muscle weakness, which in time causes functional impairment. To quantify the extent of disease progression, muscle force and functional ability can be measured. Which of these parameters changes most depends on the disease stage. In a previous study, we reported normal values for muscle force obtained by hand-held dynamometry in healthy children aged 4-16 years. In the present study, we report normal values for timed functional tests in healthy children aged 4-11 years. These normal values were compared with values obtained in 16 ambulant patients with Duchenne muscular dystrophy (DMD) aged 5-8 years to study the extent of functional impairment. In ambulant patients with DMD, we found that muscle function assessed by timed functional tests (running 9 m and rising up from the floor) and muscle force assessed by hand-held dynamometry were severely impaired. However, a small reduction of muscle force was accompanied by a large reduction in functional ability. Therefore, in our group of ambulant patients with DMD, timed functional testing was the most sensitive parameter to determine the extent of disease progression. Timed functional testing may therefore be considered as an additional outcome measure in drug trials to evaluate the effects of therapy in ambulant patients with DMD and possibly in other neuromuscular disorders. PMID:16102988
Beenakker, Ernesto A C; Maurits, Natalia M; Fock, Johanna M; Brouwer, Oebele F; van der Hoeven, Johannes H
Background Duchenne muscular dystrophy (DMD) is a sex-linked inherited muscle disease characterized by a progressive loss in muscle strength and respiratory muscle involvement. After 12 years of age, lung function declines at a rate of 6 % to 10.7 % per year in patients with DMD. Steroid therapy has been proposed to delay the loss of motor function and also the respiratory involvement. Method In 21 patients with DMD aged between seven and 16 years, the forced vital capacity (FVC) and the forced expiratory volume in one second (FEV1) were evaluated at three different times during a period of two years. Results We observed in this period of evaluation the maintenance of the FVC and the FEV1 in this group of patients independently of chronological age, age at onset of steroid therapy, and walking capacity. Conclusion The steroid therapy has the potential to stabilize or delay the loss of lung function in DMD patients even if they are non-ambulant or older than 10 years, and in those in whom the medication was started after 7 years of age.
Duchenne muscular dystrophy (DMD) causes profound and progressive muscle weakness and loss, resulting in early death. DMD is usually caused by frameshifting deletions in the gene DMD, which leads to absence of dystrophin protein. Dystrophin binds to F-actin and components of the dystrophin-associated glycoprotein complex and protects the sarcolemma from contraction-induced injury. Antisense oligonucleotide-mediated exon skipping is a promising therapeutic approach aimed at restoring the DMD reading frame and allowing expression of an intact dystrophin glycoprotein complex. To date, low levels of dystrophin protein have been produced in humans by this method. We performed a small-molecule screen to identify existing drugs that enhance antisense-directed exon skipping. We found that dantrolene, currently used to treat malignant hyperthermia, potentiates antisense oligomer-guided exon skipping to increase exon skipping to restore the mRNA reading frame, the sarcolemmal dystrophin protein, and the dystrophin glycoprotein complex in skeletal muscles of mdx mice when delivered intramuscularly or intravenously. Further, dantrolene synergized with multiple weekly injections of antisense to increase muscle strength and reduce serum creatine kinase in mdx mice. Dantrolene similarly promoted antisense-mediated exon skipping in reprogrammed myotubes from DMD patients. Ryanodine and Rycal S107, which, like dantrolene, targets the ryanodine receptor, also promoted antisense-driven exon skipping, implicating the ryanodine receptor as the critical molecular target. PMID:23241744
Kendall, Genevieve C; Mokhonova, Ekaterina I; Moran, Miriana; Sejbuk, Natalia E; Wang, Derek W; Silva, Oscar; Wang, Richard T; Martinez, Leonel; Lu, Qi L; Damoiseaux, Robert; Spencer, Melissa J; Nelson, Stanley F; Miceli, M Carrie
The present study provides evidence that abnormal patterns of global histone modification are present in the skeletal muscle nuclei of mdx mice and Duchenne muscular dystrophy (DMD) patients. A combination of specific histone H3 modifications, including Ser-10 phosphorylation, acetylation of Lys 9 and 14, and Lys 79 methylation, were found enriched in muscle biopsies from human patients affected by DMD and in late-term fetuses, early postnatal pups, or adult mdx mice. In this context, chromatin immunoprecipitation experiments showed an enrichment of these modifications at the loci of genes involved in proliferation or inflammation, suggesting a regulatory effect on gene expression. Remarkably, the reexpression of dystrophin induced by gentamicin treatment or the administration of nitric oxide (NO) donors reversed the abnormal pattern of H3 histone modifications. These findings suggest an unanticipated link between the dystrophin-activated NO signaling and the remodeling of chromatin. In this context, the regulation of class IIa histone deacetylases (HDACs) 4 and 5 was found altered as a consequence of the reduced NO-dependent protein phosphatase 2A activity, indicating that both NO and class IIa HDACs are important for satellite cell differentiation and gene expression in mdx mice. In conclusion, this work provides the first evidence of a role for NO as an epigenetic regulator in DMD. PMID:19264835
Colussi, Claudia; Gurtner, Aymone; Rosati, Jessica; Illi, Barbara; Ragone, Gianluca; Piaggio, Giulia; Moggio, Maurizio; Lamperti, Costanza; D'Angelo, Grazia; Clementi, Emilio; Minetti, Giulia; Mozzetta, Chiara; Antonini, Annalisa; Capogrossi, Maurizio C; Puri, Pier Lorenzo; Gaetano, Carlo
Duchenne muscular dystrophy (DMD) is a severe, progressive, X-linked muscle-wasting disorder with an incidence of approximately 1/3,500 male births. Females are also affected, in rare instances. The manifestation of mild to severe symptoms in female carriers of dystrophin mutations is often the result of the preferential inactivation of the X chromosome carrying the normal dystrophin gene. The severity of the symptoms is dependent on the proportion of cells that have inactivated the normal X chromosome. A skewed pattern of X inactivation is also responsible for the clinical manifestation of DMD in females carrying X;autosome translocations, which disrupt the dystrophin gene. DMD may also be observed in females with Turner syndrome (45,X), if the remaining X chromosome carries a DMD mutation. We report here the case of a karyotypically normal female affected with DMD as a result of homozygosity for a deletion of exon 50 of the dystrophin gene. PCR analysis of microsatellite markers spanning the length of the X chromosome demonstrated that homozygosity for the dystrophin gene mutation was caused by maternal isodisomy for the entire X chromosome. This finding demonstrates that uniparental isodisomy of the X chromosome is an additional mechanism for the expression of X-linked recessive disorders. The proband's clinical presentation is consistent with the absence of imprinted genes (i.e., genes that are selectively expressed based on the parent of origin) on the X chromosome. Images Figure 1 Figure 2
Quan, F; Janas, J; Toth-Fejel, S; Johnson, D B; Wolford, J K; Popovich, B W
The typical form of congenital muscular dystrophy (CMD) described in Western countries is generally considered different from its Japanese variant because of the absence of CNS involvement. Evaluations from both a clinical and a neuroradiological point of view were made of the CNS functions of 12 unselected Western children affected by CMD. In five patients, clinical observation and intelligence tests showed a mild to severe mental retardation. One of these patients suffered also from a severe form of epilepsy. In the same five patients, various degrees of white matter hypodensity, ventricular enlargement and cerebral atrophy were also detected. Similar neuroradiological abnormalities were also found in five of the seven children who did not have clinical symptoms or signs of CNS involvement. In one of these cases, necropsy neuropathological examination showed the gyral anomalies characteristic of the Japanese type of CMD. This study clearly indicates the high frequency of subclinical CNS alterations in typical Western CMD, suggesting that it should be considered a type of myoencephalopathy like its Japanese counterpart. Images
Trevisan, C P; Carollo, C; Segalla, P; Angelini, C; Drigo, P; Giordano, R
Monozygotic twin girls, both carriers of Duchenne muscular dystrophy, only one a severe symptomatic carrier and the other asymptomatic due to opposite lyonization, were studied. Myoblast clones were obtained from a muscle biopsy of the asymptomatic carrier. PCR amplification showed that most (94%) of these clones produced normal dystrophin mRNA. Roughly 704 million myoblasts were produced from 119 clones. These myoblasts were transplanted into the extensor carpi radialis (ECR) and in the biceps of one arm of the manifesting carrier while the other arm acted as the control. The strength of the patient was evaluated in a series of pre- and post-tests and a biopsy was obtained about 1 yr after the transplantation. The myoblast injections produced a significant force gain (12%-31%) in wrist extension but no force gain for elbow flexion. Muscle biopsies on the injected and control muscles obtained 1 yr after the injections showed only a small increase in the number of dystrophin positive fibers and the presence of numerous small type II fibers. The small beneficial effect of this transplantation cannot be attributed to immune problems, the donor and the recipient being identical twins, but may be due to a low level of spontaneous muscle regeneration. PMID:8186717
Tremblay, J P; Bouchard, J P; Malouin, F; Théau, D; Cottrell, F; Collin, H; Rouche, A; Gilgenkrantz, S; Abbadi, N; Tremblay, M
The generation of disease-specific induced pluripotent stem cell (iPS cell) lines from patients with incurable diseases is a promising approach for studying disease mechanisms and for drug screening. Such innovation enables us to obtain autologous cell sources for regenerative medicine. Herein, we report the generation and characterization of iPS cells from the fibroblasts of patients with a family history of Duchenne muscular dystrophy (DMD); these fibroblasts were obtained from patients at 22 gestational weeks of age and exhibit exon duplication from exons 16 to 42. The DMD-iPS cells were generated by the ectopic expression of four transcription factors: OCT4, SOX2, KLF4, and c-MYC; the DMD-iPS cells expressed several pluripotency markers and could be differentiated into various somatic cell types both in vitro and in vivo. Furthermore, DMD-iPSCs showed the differentiation potential to neuronal lineage. Thus, DMD-iPS cells are expected to serve as an in vitro disease model system, which will lay a foundation for the production of autologous cell therapies that avoid immune rejection and enable the correction of gene defects prior to tissue reconstitution. PMID:23528047
Luo, Yumei; Fan, Yong; Chen, Xinjie; Yue, Lei; Yu, Bolan; Li, Qing; Chen, Yaoyong; Sun, Xiaofang
The basis for cognitive impairment in Duchenne muscular dystrophy (DMD) is not well understood but may be related to abnormal expression of dystrophin in brain. The aim of this study was to determine whether regional brain glucose metabolism is altered in children with DMD and whether such metabolic disturbances are localized to regions shown to be normally rich in dystrophin expression. Ten boys (mean age, 11.8 years) with DMD and 17 normal adults as a control group (mean age, 27.6 years) underwent 2-deoxy-2[(18)F]fluoro-D-glucose positron emission tomography (PET) and neuropsychological evaluation. The PET data were analyzed by statistical parametric mapping (SPM). The SPM analysis showed five clusters of decreased glucose metabolism in children with DMD, including the medial temporal structures and cerebellum bilaterally and the sensorimotor and lateral temporal cortex on the right side. At the voxel level, significant glucose hypometabolism was found in the right postcentral and middle temporal gyri, uncus, and VIIIB cerebellar lobule, as well as in the left hippocampal gyrus and cerebellar lobule. The neuropsychological profile of the DMD group revealed borderline nonverbal intellectual functioning, impaired manual dexterity bilaterally, borderline cognitive functioning, and internalizing behavioral difficulties. Our findings demonstrate region-specific hypometabolism, as well as cognitive and behavioral deficits in DMD children. As the regions showing hypometabolism on PET include those normally rich in dystrophin expression, it will be important to determine whether the hypometabolic regions also show cytoarchitectural abnormalities related to the lack of dystrophin. PMID:12362416
Lee, Joon Soo; Pfund, Zoltán; Juhász, Csaba; Behen, Michael E; Muzik, Otto; Chugani, Diane C; Nigro, Michael A; Chugani, Harry T
The human X chromosome carries regions prone to genomic instability: deletions in the Xp22.31 region, involving the steroid sulfatase gene (STS) cause X-linked ichthyosis; rearrangements in the Xp21.2 region are associated with Duchenne or Becker muscular dystrophies (DMD or BMD); and the Xq27.3 unstable region, containing the (CGG)n repeat expansion in the FMR1 gene is associated with fragile X syndrome. We report on a family with two affected boys, the elder diagnosed with fragile X syndrome, the younger with DMD, and both suffering from severe ichthyosis. The family was analyzed by polymerase chain reaction, multiplex ligation-dependent probe amplification and haplotype analysis. The mother proved to be an asymptomatic carrier of all three non-contiguous mutation events, involving the STS gene, the DMD gene and a FMR1 expansion. To the best of our knowledge, this is the first description of an asymptomatic carrier of three different X-linked disorders, involving severe genetic rearrangements on both long and short arms of the X chromosomes. The boy with fragile X syndrome has inherited a triple recombinant maternal X chromosome, this way inheriting the FMR1 expansion and ichthyosis, originating most probably from different maternal Xes and excluding the DMD gene deletion. The transmission of these extremely defective maternal chromosomes to the next generation involved several recombinations. PMID:23574351
Todorova, A; Litvinenko, I; Todorov, T; Tincheva, R; Avdjieva, D; Tincheva, S; Mitev, V
Background Myostatin is a potent muscle growth inhibitor that belongs to the Transforming Growth Factor-? (TGF-?) family. Mutations leading to non functional myostatin have been associated with hypermuscularity in several organisms. By contrast, Duchenne muscular dystrophy (DMD) is characterized by a loss of muscle fibers and impaired regeneration. In this study, we aim to knockdown myostatin by means of exon skipping, a technique which has been successfully applied to reframe the genetic defect of dystrophin gene in DMD patients. Methods We targeted myostatin exon 2 using antisense oligonucleotides (AON) in healthy and DMD-derived myotubes cultures. We assessed the exon skipping level, transcriptional expression of myostatin and its target genes, and combined myostatin and several dystrophin AONs. These AONs were also applied in the mdx mice models via intramuscular injections. Results Myostatin AON induced exon 2 skipping in cell cultures and to a lower extent in the mdx mice. It was accompanied by decrease in myostatin mRNA and enhanced MYOG and MYF5 expression. Furthermore, combination of myostatin and dystrophin AONs induced simultaneous skipping of both genes. Conclusions We conclude that two AONs can be used to target two different genes, MSTN and DMD, in a straightforward manner. Targeting multiple ligands of TGF-beta family will be more promising as adjuvant therapies for DMD.
Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset syndrome characterized by progressive degeneration of specific muscles. OPMD is caused by extension of a polyalanine tract in poly(A) binding protein nuclear 1 (PABPN1). Insoluble nuclear inclusions form in diseased muscles. We have generated a Drosophila model of OPMD that recapitulates the features of the disorder. Here, we show that the antiprion drugs 6-aminophenanthridine (6AP) and guanabenz acetate (GA), which prevent formation of amyloid fibers by prion proteins in cell models, alleviate OPMD phenotypes in Drosophila, including muscle degeneration and nuclear inclusion formation. The large ribosomal RNA and its activity in protein folding were recently identified as a specific cellular target of 6AP and GA. We show that deletions of the ribosomal DNA locus reduce OPMD phenotypes and act synergistically with sub-effective doses of 6AP. In a complementary approach, we demonstrate that ribosomal RNA accelerates in vitro fibril formation of PABPN1 N-terminal domain. These results reveal the conserved role of ribosomal RNA in different protein aggregation disorders and identify 6AP and GA as general anti-aggregation molecules.
Barbezier, Nicolas; Chartier, Aymeric; Bidet, Yannick; Buttstedt, Anja; Voisset, Cecile; Galons, Herve; Blondel, Marc; Schwarz, Elisabeth; Simonelig, Martine
Efficient and widespread gene transfer is required for successful treatment of Duchenne muscular dystrophy (DMD). Here, we performed the first clinical trial using a chimeric adeno-associated virus (AAV) capsid variant (designated AAV2.5) derived from a rational design strategy. AAV2.5 was generated from the AAV2 capsid with five mutations from AAV1. The novel chimeric vector combines the improved muscle transduction capacity of AAV1 with reduced antigenic crossreactivity against both parental serotypes, while keeping the AAV2 receptor binding. In a randomized double-blind placebo-controlled phase I clinical study in DMD boys, AAV2.5 vector was injected into the bicep muscle in one arm, with saline control in the contralateral arm. A subset of patients received AAV empty capsid instead of saline in an effort to distinguish an immune response to vector versus minidystrophin transgene. Recombinant AAV genomes were detected in all patients with up to 2.56 vector copies per diploid genome. There was no cellular immune response to AAV2.5 capsid. This trial established that rationally designed AAV2.5 vector was safe and well tolerated, lays the foundation of customizing AAV vectors that best suit the clinical objective (e.g., limb infusion gene delivery) and should usher in the next generation of viral delivery systems for human gene transfer.
Bowles, Dawn E; McPhee, Scott WJ; Li, Chengwen; Gray, Steven J; Samulski, Jade J; Camp, Angelique S; Li, Juan; Wang, Bing; Monahan, Paul E; Rabinowitz, Joseph E; Grieger, Joshua C; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Xiao, Xiao; Samulski, R Jude
Traditional measures of respiratory function in children with Duchenne muscular dystrophy (DMD) are based on maximal inspiratory pressure (PImax) and vital capacity (VC). Sniff nasal inspiratory pressure (SNIP) measurements are easily performed by young children with neuromuscular disorders. The clinical value of SNIP in the longitudinal assessment of respiratory weakness remains to be assessed. The objective of the present study was to assess longitudinally the changes in SNIP, PImax and VC with age in DMD children. We hypothesised that their longitudinal assessment would show an earlier decline in SNIP than VC. A 3-year, prospective follow-up, at 6-month intervals of, 33 steroid-naïve, 5-20-year-old DMD patients was analysed using a linear mixed model. SNIP measurements were reliable (within-session coefficient of variation 8%). SNIP and VC increased until 10.5 and 12.5 years of age, respectively, and declined thereafter, while PImax did not change with age. SNIP was an earlier marker of decline in respiratory muscle strength (at 10.5 years) than VC (at 12.5 years) in young DMD patients. SNIP longitudinal assessment is useful in the detection of inspiratory strength decline in young DMD patients when VC values remain within normal values and as an outcome measure in clinical trials for emerging therapeutics in young DMD patients from the age of 5 years. PMID:23258781