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OBJECTIVE@#To characterize the paraspinal muscles of adolescent idiopathic scoliosis (AIS) patients, and to further explore its etiology.@*METHODS@#Clinical records and paraspinal muscle biopsies at the apex vertebra region during posterior scoliosis correction surgery of 18 AIS were collected from November 2018 to August 2019. Following standardized processing of fresh muscle tissue biopsy, serial sections with conventional hematoxylin-eosin (HE) and histochemical and immunohistochemical (IHC) with antibody Dystrophin-1 (R-domain), Dystrophin-2 (C-terminal), Dystrophin-3 (N-terminal), Dystrophin-total, Myosin (fast), major histocompatibility complex 1 (MHC-1), CD4, CD8, CD20, and CD68 staining were obtained. Biopsy samples were grouped according to the subjects' median Cobb angle (Cobb angle ≥ 55° as severe AIS group and Cobb angle < 55° as mild AIS group) and Nash-Moe's classification respectively, and the corresponding pathological changes were compared between the groups statistically.@*RESULTS@#Among the 18 AIS patients, 8 were in the severe AIS group (Cobb angle ≥55°) and 10 in the mild AIS group (Cobb angle < 55°). Both severe and mild AIS groups presented various of atrophy and degeneration of paraspinal muscles, varying degrees and staining patterns of immune-expression of Dystrophin-3 loss, especially Dystrophin-2 loss in severe AIS group with significant differences, as well as among the Nash-Moe classification subgroups. Besides, infiltration of CD4+ and CD8+ cells in the paraspinal muscles and tendons was observed in all the patients while CD20+ cells were null. The expression of MHC-1 on myolemma was present in some muscle fibers.@*CONCLUSION@#The histologic of paraspinal muscle biopsy in AIS had similar characteristic changes, the expression of Dystrophin protein was significantly reduced and correlated with the severity of scoliosis, suggesting that Dystrophin protein dysfunctions might contribute to the development of scoliosis. Meanwhile, the inflammatory changes of AIS were mainly manifested by T cell infiltration, and there seemed to be a certain correlation between inflammatory cell infiltration, MHC-1 expression and abnormal expression of Dystrophin. Further research along the lines of this result may open up new ideas for the diagnosis of scoliosis and the treatment of paraspinal myopathy.
Subject(s)
Humans , Adolescent , Scoliosis/surgery , Paraspinal Muscles/pathology , Dystrophin , Non-alcoholic Fatty Liver Disease/pathology , Kyphosis/pathology , BiopsyABSTRACT
Duchenne Muscular Dystrophy (DMD) is a genetic disorder involving progressive muscle deterioration leading to loss of mobility, cardiomyopathy, and respiratory complications leading to an early death by the fourth decade of life. Males are affected more often as DMD results from a mutation in the dystrophin gene residing on the X chromosome. The DMD genetic mutation results in a complete functional lack of dystrophin, which culminates as an inadequate connection between the intracellular actin filaments and the extracellular skeleton of muscle. Boys affected by DMD clinically present with muscle weakness before age five, are often wheelchair-bound by age 12, and rarely survive beyond the third decade of life. Traditional treatment strategies have focused primarily on quality-of-life improvement and have included the use of glucocorticoids and physical therapy. No cure currently exists, however many novel treatments for DMD are currently being explored. Some of these involve gene therapy, exon skipping, stop codon skipping, CRISPR technology interventions, and the use of a retinal dystrophin isoform. In this comprehensive review, we recapitulate the literature findings to summarize the history, epidemiology, genetics, clinical presentation, diagnosis, and current and future strategies for the treatment of Duchenne Muscular Dystrophy.
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Neuromuscular diseases represent a rare cause of dilated myocardiopathy, among them Duchenne muscular dystrophy is the most common. Transthoracic echocardiography and cardiac magnetic resonance imaging can assess cardiac involvement early. The case of a patient diagnosed with Duchenne muscular dystrophy who develops cardiac involvement during cardiology follow-up is presented below.
Subject(s)
Humans , Male , Adult , Muscular Dystrophy, Duchenne/diagnosis , Muscular Dystrophy, Duchenne/genetics , Muscular Dystrophy, Duchenne/therapy , Cardiomyopathy, Dilated , Dystrophin/genetics , Muscular Dystrophy, Duchenne/classification , Muscular Dystrophy, Duchenne/physiopathology , Diagnosis, Differential , Heart FailureABSTRACT
Hypertrophic feline muscular dystrophy (HFMD), rarely reported in the literature, is a disease caused by a hereditary recessive dystrophin deficiency linked to the X chromosome, mainly affecting young male cats. Here, we presented the clinical aspects, food management, and clinical evolution of a seven-year-old mixed-breed cat diagnosed with HFMD, having a primary history of progressive tongue protrusion.
A distrofia muscular hipertrófica felina é uma doença causada por uma deficiência da distrofina com caráter hereditário recessivo ligado ao cromossomo X, com poucos registros de ocorrência na literatura, que acomete principalmente gatos machos jovens. Neste trabalho, são relatados os aspectos clínicos, manejo alimentar e evolução clínica de um gato, sem raça definida, de sete anos com histórico principal de protrusão progressiva da língua e diagnosticado com distrofia muscular hipertrófica felina.
Subject(s)
Animals , Male , Cats , Dystrophin/genetics , Macroglossia/veterinary , Muscular Dystrophy, Animal/therapy , Biopsy/veterinaryABSTRACT
Duchenne muscular dystrophy(DMD) is an X-linked hereditary neuromuscular disorder caused by dystrophin gene mutation.About 1/3 of DMD patients have cognitive impairment.Early detection of cognitive impairment is essential for early diagnosis and the quality of life.This review summarized the recent progress in the clinical features, pathogenesis, brain structure changes, and cognitive impairment intervention of DMD.
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Duchenne muscular dystrophy (DMD) is a serious and progressive hereditary muscle disease. The DMD gene mutation on the X chromosome causes the loss of dystrophin, causing progressive muscle weakness and muscular atrophy. Most patients die for heart and lung failure. Current gene therapy methods are mainly aimed at restoring the expression of dystrophin, including read-through therapy, exon skipping therapy, vector-mediated gene replacement therapy and gene editing therapy. This article reviews the mechanisms of these different treatments and important advances in clinical research, and analyzes the challenges and application prospects of these treatments.
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Background Duchenne muscular dystrophy (DMD) is an X-linked inherited neuromuscular disorder due tomutations in the dystrophin gene. Animal models that accurately reflect pathological conditions and diseasecharacteristics are key factors in the discovery and development of new anti-DMD drugs.Aim Here, we evaluated motor behavior, pathological and biochemical characters of a new DMD mouse modelbuilt up by the Nanjing Biomedical Research Institute of Nanjing University (NBRI).Methods The pole test and open-field test were used to assess the movement disorders in DMD mouse model.The gastrocnemius (GAS), biceps, triceps, soleus, and tibialis anterior muscles of mice were subjected to weight analysis to evaluate the skeletal muscle pseudohypertrophy. Meanwhile, immunofluorescence andWestern blotting were used to detect the expression of dystrophin in the GAS. Serum levels of creatine kinase(CK) and lactate dehydrogenase (LDH) that accurately reflect muscle damage were detected. Masson stainingwas used to evaluate the fibrosis of GAS and diaphragm (DIA).Results The novel DMD mouse showed significant behavioral disorders and exhibited high serum levels of CKand LDH. Western blotting and immunofluorescence staining showed decreased significantly with dystrophinlevel in the GAS. Besides, the mdx mouse of DMD developed fibrosis in both GAS and DIA.Conclusion Taken together, our results indicated that the behavioral, biochemical and pathologicalcharacterization of the mdx mouse model is similar to human DMD. This mdx mouse model may provideinsights into the pathophysiology of DMD and the effects of anti-DMD drugs.
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Resumen Para las distrofias musculares no miotónicas como la Distrofia de Duchenne y la Distrofia de Becker, la cardiopatía forma parte inherente de su espectro clínico. La expresión clínica de éstas se puede manifestar con insuficiencia cardíaca des- compensada, arritmias o muerte súbita; gran parte de ellos cursan asintomáticos en el transcurso del tiempo, pero cuando se manifiestan constituyen una de las principales causas de muerte en estos pacientes, por lo que su detección temprana y tratamiento óptimo influyen en gran medida en el pronóstico clínico de estos pacientes. A continuación, se presenta el caso de un paciente en quien se encontró de forma incidental el compromiso cardíaco de uno de estos desórdenes neuromusculares.
Abstract Cardiac involvement in muscular dystrophies: a clinical case For non-myotonic muscular dystrophies such as Duchenne Dystrophy and Becker Dystrophy, heart disease is an inherent part of its clinical spectrum. The clinical expression of these diseases can be manifested with decompensated heart failure, arrhythmias or sudden death; A large part of them are asymptomatic over time, but when they manifest they constitute one of the main causes of death in these patients, so their early detection and optimal treatment greatly influence the clinical prognosis of these patients. The following is the case of a patient in whom the cardiac involvement of one of these neuromuscular disorders was found incidentally.
Subject(s)
Humans , Male , Adult , Heart Failure/diagnostic imaging , Muscular Dystrophies/complicationsABSTRACT
RESUMEN Las distrofias musculares de Duchenne/Becker son enfermedades raras que reciben poca atención en nuestro medio. El objetivo del presente estudio fue implementar la técnica de amplificación múltiple dependiente de ligación por sondas (MLPA) y demostrar que tiene ventajas sobre la técnica de reacción en cadena de la polimerasa multiplex (PCR-multiplex). Se analizaron muestras de 40 individuos con diagnóstico presuntivo de distrofia muscular de Duchenne/Becker, primero por PCR-multiplex y luego por MLPA. Con la PCR-multiplex se detectaron 15 individuos con deleciones causales y con la técnica MLPA se logró diagnosticar a 21 individuos, cuatro duplicaciones y 17 deleciones. En conclusión, la técnica MLPA logra detectar mutaciones de tipo deleción y duplicación de exones, consiguiendo un mayor número de diagnósticos moleculares por alteraciones en el gen DMD.
ABSTRACT Duchenne and Becker muscular dystrophies are rare diseases that receive limited attention in our field. The objective of this study was to implement the Multiplex Ligation-dependent Probe Amplification technique (MLPA) and to demonstrate that it has advantages over the Multiplex Polymerase Chain Reaction (Multiplex PCR) technique. Samples from 40 individuals with a presumptive diagnosis of Duchenne and Becker muscular dystrophies were analyzed: first by Multiplex PCR and then by MLPA. Fifteen individuals with causal deletions were detected with Multiplex PCR, while the MLPA technique was able to diagnose 21 individuals, four duplications, and 17 deletions. In conclusion, the MLPA technique can detect mutations of the exon deletion and duplication type, yielding a larger number of molecular diagnoses due to alterations in the DMD gene.
Subject(s)
Adolescent , Child , Humans , Male , Muscular Dystrophy, Duchenne/genetics , Multiplex Polymerase Chain Reaction/methods , Mutation , Pedigree , Prospective StudiesABSTRACT
Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are caused by mutations in the DMD gene. The aim of this study is to identify pathogenic DMD variants in probands and reduce the risk of recurrence of the disease in affected families. Variations in 100 unrelated DMD/BMD patients were detected by multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS). Pathogenic variants in DMD were successfully identified in all cases, and 11 of them were novel. The most common mutations were intragenic deletions (69%), with two hotspots located in the 5′ end (exons 2–19) and the central of the DMD gene (exons 45–55), while point mutations were observed in 22% patients. Further, c.1149+1G>A and c.1150-2A>G were confirmed by hybrid minigene splicing assay (HMSA). This two splice site mutations would lead to two aberrant DMD isoforms which give rise to severely truncated protein. Therefore, the clinical use of MLPA, NGS, and HMSA is an effective strategy to identify variants. Importantly, eight embryos were terminated pregnancies according to prenatal diagnosis and a healthy boy was successfully delivered by preimplantation genetic diagnosis (PGD). Early and accurate genetic diagnosis is essential for prenatal diagnosis/PGD to reduce the risk of recurrence of DMD in affected families.
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Objective@#To carry out genetic testing and prenatal diagnosis for a family affected with Duchenne muscular dystrophy (DMD).@*Methods@#Multiplex ligation dependent probe amplification (MLPA) was used to detect potential deletion and duplication of the Dystrophin gene. Haplotype analysis was performed using five short tandem repeat polymorphism loci (3'-STR, 5'-STR, 45-STR, 49-STR, 50-STR of the DMD gene.@*Results@#A same deletional mutation (exons 51-55) of the DMD gene was detected in two brothers but not in their mother. The patients and fetus have inherited different haplotypes of the Dystrophin gene from their mother, suggesting that the fetus was unaffected.@*Conclusion@#The mother was very likely to harbor germline mosaicism for the Dystrophin gene variant. Genetic testing of peripheral blood samples cannot rule out germline mosaicism in the mother. Prenatal diagnosis should be provided for subsequent pregnancies in this family.
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OBJECTIVE:(DMD),summarize the gene mutation hotspots in 97 cases and to explore the correlation between clinical manifestations and genotype. METHODS: Totally 97 patients with DMD diagnosed by genetic examination from January 2014 to 2018 were collected and analyzed. The clinical manifestations,serum analyses and gene mutation results were analyzed. RESULTS: The main clinical manifestations of 97 patients(96 boys)were feeding difficulties,increased muscle enzyme and limb weakness.Creatine kinase(CK),lactate dehydrogenase(LDH)and aspartate aminotransferase(AST)muscle enzymes were significantly increased. By combining deep-sequencing technologies,the large deletions of DMD gene mutation was in 62 cases(63.92%);there were 11 cases(11.34%)of large duplication mutation,and 24 cases(24.74%)of point mutation. All of the mutations could occur in any position in the DMD gene,but there were two hot spots;45 cases were located in the central region gene exon 45～55(72.58%);12 cases of deletion mutation were located in 5'exon end exon 2～19 area(19.35%). CONCLUSION: The main clinical manifestations of the DMD children are feeding difficulty,increased muscle enzyme and limb weakness.The patients with significantly increased muscle enzyme should receive a timely defection of DMD gene.
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Duchenne muscular dystrophy (DMD) is a severe muscular genetic disorder,which is caused by a mutation in the DMD gene encoding the dystrophin protein.The clinical manifestation of DMD is the progressive muscular dystrophy.Myostatin is a negative regulator of skeletal muscle growth and development.In recent years,it has received extensive attention in the treatment of muscle diseases.This review focuses on the structural and activity of myostatin,its regulation of skeletal muscle growth and noval approaches to Myostatin inhibitor in the treatment of DMD.
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Dystrophinopathy is a group of inherited diseases caused by the defect of dystrophin protein with X-linked recessive inheritance.The disease is clinically characterized by progressive severe muscles weakness and atrophy of proximal limb muscles and belt muscle,gastrocnemius pseudohypertrophy.The patient lose the ability of daily exercise,and ultimately succumb to restrictive lung disease or cardiac death.According to the clinical manifestations and the defect degree of dystrophin protein,dystrophinopathy is divided into:Duchenne muscular dystrophy (DMD),Becker muscular dystrophy,X-linked dilated cardiomyopathy,and female carrier of DMD.Patients can present with multi-system involvement at different stages of the disease,which require multidisciplinary management to alleviate symptoms,prolong life and improve quality of life.Glucocorticoids can significantly extend the independent activity of children by 2-5 years.Due to the high incidence,poor quality of life in the early stage and high disability and lethality in the late stage,it is important to strengthen the understanding of neurologists about this disease and conduct early diagnosis,full management and genetic counseling.
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An effective therapeutic method for muscular dystro-phy is unavailable now;however,the research and development of anti-muscular dystrophy drugs need appropriate animal mod-els. Researchers focus on Caenorhabditis elegans because of the andvantages such as the transparent body, short life cycle, and high homology with human genes. The Caenorhabditis elegans mutant strains show musucular dystrophy phenotype similar to human diseases. In this paper,the application of Caenorhabditis elegans models in muscular dystrophy research has been re-viewed.
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<p><b>Background</b>Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are common X-linked recessive neuromuscular disorders caused by mutations in dystrophin gene. Multiplex polymerase chain reaction (multiplex PCR) and multiplex ligation-dependent probe amplification (MLPA) are the most common methods for detecting dystrophin gene mutations. This study aimed to contrast the two methods and discern the genetic characterization of patients with DMD/BMD in Eastern China.</p><p><b>Methods</b>We collected 121 probands, 64 mothers of probands, and 15 fetuses in our study. The dystrophin gene was detected by multiplex PCR primarily in 28 probands, and MLPA was used in multiplex PCR-negative cases subsequently. The dystrophin gene of the remaining 93 probands and 62 female potential carriers was tested by MLPA directly. In fetuses, multiplex PCR and MLPA were performed on 4 fetuses and 10 fetuses, respectively. In addition, sequencing was also performed in 4 probands with negative MLPA.</p><p><b>Results</b>We found that 61.98% of the subjects had genetic mutations including deletions (50.41%) and duplications (11.57%). There were 43.75% of mothers as carriers of the mutation. In 15 fetuses, 2 out of 7 male fetuses were found to be unhealthy and 2 out of 8 female fetuses were found to be carriers. Exons 3-26 and 45-52 have the maximum frequency in mutation regions. In the frequency of exons individually, exon 47 and exon 50 were the most common in deleted regions and exons 5, 6, and 7 were found most frequently in duplicated regions.</p><p><b>Conclusions</b>MLPA has better productivity and sensitivity than multiplex PCR. Prenatal diagnosis should be applied in DMD high-risk fetuses to reduce the disease incidence. Furthermore, it is the responsibility of physicians to inform female carriers the importance of prenatal diagnosis.</p>
Subject(s)
Female , Humans , Male , Pregnancy , China , Dystrophin , Genetics , Exons , Genetics , Gene Deletion , Heterozygote , Multiplex Polymerase Chain Reaction , Muscular Dystrophy, Duchenne , Genetics , Mutation , Genetics , Sequence DeletionABSTRACT
Objective: To deepen the understanding of Duchenne/Becker muscular dystrophy by investigating dystrophin (DMD) gene variants in 2 Chinese Han families with this disease. Methods: Retrospective analysis of the clinical characteristics of the probands in two families with Duchnne/ Becker muscular dystrophy and the results of multiplex ligation-dependent probe amplification (MLPA) for the probands and their relatives was performed. Results: Three probands were identified by significantly-elevated creatine kinase levels. Two probands in family one are fraternal twin brothers with the same deletions of exons 8-9, while their mother has no abnormality at this site. The proband in family two is the little brother in a pair of fraternal twins with duplication of exons 48-51, and his mother has heterozygous duplication of exons 48-51. Conclusion: ① The presence of the same DMD gene mutation in the fraternal twins suggests that the mother may be a gonad chimera with this mutation if her gene detection of peripheral blood is normal. The mother must undergo prenatal gene diagnosis to reduce the risk of Duchenne/Becker muscular dystrophy in her offsprings. ② The exons 48-51 duplication of DMD gene is pathogenic mutation.
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La distrofia muscular de Duchenne es una enfermedad muscular grave ligada al cromosoma X que afecta el gen que codifica la distrofina, proteína fundamental para el mantenimiento de la fibra muscular. Se caracteriza por debilidad muscular de inicio en la infancia que sigue un curso progresivo. Sin intervención alguna, los pacientes pierden la marcha antes de la adolescencia y el fallecimiento ocurre en la segunda década de la vida por complicaciones respiratorias o problemas cardiacos. Actualmente no existe tratamiento curativo, pero la terapia con corticoides y el manejo multidisciplinario y ortopédico modifican la historia natural de esta miopatía. En este artículo se presentan dos casos clínicos de niños que presentaron dificultad para realizar actividades físicas vigorosas. Se les diagnosticó distrofia muscular de Duchenne confirmada por creatina-fosfocinasa y electromiografía, con mejoría del cuadro clínico, gracias al tratamiento instaurado.
The Duchenne muscular dystrophy is a bound serious muscular illness to the X-linked chromosome that affects to the gene that codes the dystrophin, protein important for the maintenance of the muscle fiber. It is characterized by muscle weakness of beginning in the childhood that follows a progressive course. Without intervention some, the patients lose the march before the younger and the death happens in the second decade of life for breathing complications or heart problems. At the moment it doesn't exist healing treatment, but the therapy with corticosteroids and the handling several disciplines and orthopedic they modify the natural history of this muscle disorders. In this article, we present two clinical cases of children who had difficulty prefoming vigorous physical actives. Diagnosis of Duchenne muscular dystrophy confirmed by creatin phosphokinase and electromyography with improvement of the clinical picture thanks to the treatment provided.
Subject(s)
Humans , Dystrophin , Prednisone , Inheritance Patterns , ElectromyographyABSTRACT
Objective To investigate the expression changes of astrocytic syntrophin in hippocampus from human mesial temporal lobe epilepsy (MTLE). Methods From April, 2015 to July, 2016, 17 cases of hippocampus, collected from temporal lobectomy, were divided into MTLE group (n=13) and non-MTLE group (n=4) according to hematoxylin and eosin staining, glial fibrillary acidic protein and neuronal nu-clei immunohistochemical staining. Immunofluorescence double labeling and immunofluorescence histochemistry were used to observe the expression of syntrophin. Results The proliferation of astrocytes increased and neurons reduced in the hippocampus of MTLE group. Syntro-phin was found in the membrane and foot processes of astrocyte, that was enriched along perivascular astrocyte end-feet domain in non-MTLE group, but lost in MTLE group. While the whole expression of syntrophin was more in MTLE group than in non-MTLE group (t=5.421, P<0.001). Conclusion The distribution of syntrophin in hippocampus astrocytes may be related to the development of MTLE.
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Duchenne muscular dystrophy is the most prevalent muscular dystrophy caused by dystrophin gene mutations. In the central nervous systerm, there are at least six dystrophin isoforms, in which Dp140 is closely associated with cognitive impairment. This paper re-viewed the discovery, structure, gene location, detection methods and function of Dp140.