Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1762617 (weakness)
37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have identified seven patients (including two sib pairs) with a predominantly late onset limb-girdle muscular dystrophy in whom an absence of merosin was noted on immunoblotting. Merosin immunocytochemistry was normal, and no abnormalities were detected on immunostaining for the various proteins known to be involved in the limb-girdle muscular dystrophies (alpha, beta, gamma, delta sarcoglycan and calpain 3). Apart from one patient, where muscle problems began in childhood, reported age at onset of muscle weakness involving initially the proximal muscles of the lower limbs ranged from 17 to 40 years. The pattern of muscle involvement was similar from patient to patient, with hypertrophy of at least the calf muscles, absence of scapular winging and predominant involvement of hip flexors and adductors and hamstrings more than quadriceps. Serum creatine kinase in all patients was at least 10 times normal, and muscle biopsies showed non-specific dystrophic features. We believe that the patients described here may represent a genetically distinct subset within the limb-girdle muscular dystrophy group.
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PMID:Abnormal merosin in adults. A new form of late onset muscular dystrophy not linked to chromosome 6q2. 957 86

The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of disorders of progressive weakness of the pelvic and shoulder girdle musculature. The clinical course is characterized by great variability, ranging from severe forms with onset in the first decade and rapid progression resembling clinically Xp21 Duchenne muscular dystrophy (DMD) to milder forms with later onset and slower course. Eight genes are mapped for the AR-LGMDs; they are: LGMD2A (CAPN3) at 15q, LGMD2B (dysferlin) at 2p, LGMD2C (gamma-SG) at 13q, LGMD2D (alpha-SG) at 17q, LGMD2E (beta-SG) at 4q, LGMD2F (6-SG) at 5q, LGMD2G at 17q, and more recently LGMD2H at 9q. The LGMD2F (delta-SG) and LGMD2G genes were mapped in Brazilian AR-LGMD families. Linkage analysis in two unlinked families excluded the eight AR-LGMD genes, indicating that there is at least one more gene responsible for AR-LGMD. We have analyzed 140 patients (from 40 families) affected with one of seven autosomal recessive LGMD loci, that is, from LGMD2A to LGMD2G. The main observations were: 1) all LGMD2E and LGMD2F patients had a severe condition, but considerable inter- and intra-familial clinical variability was observed among patients from all other groups; 2) serum CK activities showed the highest values in LGMD2D (alpha-SG) patients among sarcoglycanopathies and LGMD2B (dysferlin) patients among nonsarcoglycanopathies; 3) comparison between LGMD2A (CAPN3) and LGMD2B (dysferlin) showed that the first have on average a more severe course and have calf hypertrophy more frequently (86% versus 13%); and 4) inability to walk on toes was observed in approximately 70% of LGMD2B patients.
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PMID:Seven autosomal recessive limb-girdle muscular dystrophies in the Brazilian population: from LGMD2A to LGMD2G. 1006 10

Autosomal recessive limb gird muscular dystrophy (LGMD2) is a clinically and genetically heterogeneous group of diseases that are characterized by progressive atrophy and weakness of the proximal limb muscles. At least eight genetic loci leading to LGMD2 are recognized. The proportion of particular gene involved in producing different forms of LGMD2 shows a marked geographical variation. We studied 19 LGMD2 patients from Russia (15 families) and found calpain 3 (CAPN3) gene mutations in most of the patients studied. Sequence analysis of the fourth exons revealed two sibs - heterozygous compound for a 15-bp deletion (nt598-612) and 550 adenine deletion, and two sibs homozygous for a 550delA. We developed assay based on allele specific amplification (ASA) for rapid screening of the 550delA. The ASA assay of the LGMD2 patients under study showed that 7 patients from 6 families were homozygous for 550delA and 7 patients from 4 families were heterozygous for 550delA. A linkage analysis employing four microsatellites flanking the LGMD2A locus was performed. We found complete haplotype identity in most cases what favors the possibility of a common founder. Heterozygous carriers of 550delA were found in general population. The crude estimate of the mutation frequency is 1/150. Hum Mutat 15:295, 2000.
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PMID:High incidence of 550delA mutation of CAPN3 in LGMD2 patients from Russia. 1067 50

Labrador retrievers suffer from an autosomal recessive muscular dystrophy of unknown aetiology. Dogs affected with this disease develop generalized weakness associated with severe, generalized skeletal muscle atrophy and mild elevations in creatine kinase in the first few months of life. The severity of signs tends to progress over the first year of life but can vary from mild exercise intolerance to non-ambulatory tetraparesis. Beyond 1 year of age, the signs usually stabilize and although muscle mass does not increase, affected dogs' strength may improve slightly. The pathological changes present on muscle biopsy include marked variation in muscle fibre size with hypertrophied and round atrophied fibres present. There is an increased number of fibres with central nuclei and split fibres can be seen. It has been suggested that the disorder is a model for limb-girdle muscular dystrophy. In recent years, mutations in genes encoding the proteolytic enzyme, calpain 3, a novel protein named dysferlin, and components of the dystrophin-glycoprotein complex have been identified as causes of autosomal recessive limb-girdle muscular dystrophy. We have evaluated these proteins in normal dogs and in three Labrador retrievers with autosomal recessive muscular dystrophy using immunohistochemistry and Western blot analysis on frozen skeletal muscle. The results demonstrate that dystrophin, the sarcoglycans, alpha-actinin, dysferlin and calpain 3 are present in the normal and affected dogs. We conclude that this autosomal recessive muscular dystrophy is not due to a deficiency of alpha-actinin, or any of the known autosomal recessive limb-girdle muscular dystrophy proteins, although we cannot rule out a malfunction of any of these proteins.
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PMID:Evaluation of the dystrophin-glycoprotein complex, alpha-actinin, dysferlin and calpain 3 in an autosomal recessive muscular dystrophy in Labrador retrievers. 1116 65

A 45-year-old housewife had proximal dominant limb muscle weakness from around 25 years of age. Her parents were cousins. None of family members was affected. Progressive muscle weakness and atrophy were prominent at the posterior compartments of legs and trunk. Serum CK was moderately elevated. Muscle pathology revealed variation in fiber size, moderate increase in numbers of internal nuclei and abundant lobulated fibers. On immunostaining using by monoclonal antibody against human calpain 3 (NCL-CALP-2 C4; Novocastra) to the biopsied muscle, calpain 3 was completely absent in the sarcoplasm, while granular debris and in part positive striation were noted in control muscle. By Western blot analysis, a band corresponding to 94 kDa of calpain 3 was not detected. A genetic analysis of calpain 3 revealed homozygous C-565-G mutation (Leu189Val). From the present study. Western blot analysis and immunostaining by using calpain 3 antibody were suggested to be useful to diagnose LGMD2A in LGMD patients.
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PMID:[A case of LGMD2A identified with both western blot analysis and immunostaining of calpain 3 in biopsied muscle]. 1129 67

Limb girdle muscular dystrophies (LGMDs) are a group of clinically heterogeneous genetic diseases characterized by progressive weakness and atrophy of scapular and pelvic muscles, with either a dominant or recessive autosomic mode of inheritance. The first symptoms of the disorder appear during the first 20 years of life and progresses gradually, and a walking disability develops 10-20 years later. The gene responsible for LGMD2A has been identified and encodes calpain 3, a protease expressed mainly in skeletal muscle. Apoptotic myonuclei were recently detected in muscular biopsy specimens of LGMD2A patients, and apoptosis was found to be correlated with altered subcellular distribution of inhibitory protein kappaBalpha (IkappaBalpha) and nuclear factor kappaB (NF-kappaB), resulting in sarcoplasmic sequestration of NF-kappaB. Calpain 3 dependent IkappaBalpha degradation was reconstituted in vitro, supporting a possible in vivo sequence of events leading from calpain 3 deficiency to IkappaBkappa accumulation, prevention of nuclear translocation of NF-kappaB, and ultimately apoptosis. Therefore calpain 3, present in healthy muscle as sarcoplasmic and nuclear forms, may control IkappaBalpha turnover and indirectly regulate NF-kappaB dependent expression of survival genes. Recent data reported from a new model of LGMD2A in mice and from other muscular disorders strengthen understanding of the molecular links between calpain 3 and the Ikappaalpha/NF-kappaB pathway. Finally, in light of the lack of apoptosis observed in inflammatory myopathies, a unifying model for the control of cell survival in muscle is proposed and discussed
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PMID:Pathophysiology of limb girdle muscular dystrophy type 2A: hypothesis and new insights into the IkappaBalpha/NF-kappaB survival pathway in skeletal muscle. 1148 17

Mutations in the calpain 3 gene have been proven to be responsible for limb-girdle muscular dystrophy (LGMD) type 2A. To determine the incidence and genotypes of the calpain 3 (p94) gene mutations in Japanese LGMD patients, we sequenced the gene in 80 patients with clinical characteristics of autosomal recessive or sporadic LGMD. We identified 13 distinct pathogenic mutations in 21 patients (26%), including seven missense mutations, four splice-site mutations and two insertions in which six were novel mutations. Among the 21 patients, 15 (71%) had three types of the common missense (G233V, R461C, D707G) and one insertion (1795-1796insA) mutation. The patients had slowly progressive muscle weakness with age of onset of the disease varying from 6 to 52 years, averaging 20.9. The most striking pathologic findings were the presence of lobulated fibers in 14 patients, especially in the advanced stages. Differing from Duchenne and Becker muscular dystrophy, opaque (hypercontracted) fibers were very rarely seen. These findings may be helpful in establishing diagnostic screening strategies in Japanese LGMD patients.
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PMID:Calpain 3 gene mutations: genetic and clinico-pathologic findings in limb-girdle muscular dystrophy. 1152 84

The molecular events by which eccentric muscle contractions induce muscle damage and remodelling remain largely unknown. We assessed whether eccentric exercise modulates the expression of proteinases (calpains 1, 2 and 3, proteasome, cathepsin B+L), muscle structural proteins (alpha-sarcoglycan and desmin), and the expression of the heat shock proteins Hsp27 and alphaB-crystallin. Vastus lateralis muscle biopsies from twelve healthy male volunteers were obtained before, immediately after, and 1 and 14 days after a 30 min downhill treadmill running exercise. Eccentric exercise induced muscle damage as evidenced by the analysis of muscle pain and weakness, creatine kinase serum activity, myoglobinaemia and ultrastructural analysis of muscle biopsies. The calpain 3 mRNA level was decreased immediately after exercise whereas calpain 2 mRNA level was increased at day 1. Both mRNA levels returned to control values by day 14. By contrast, cathepsin B+L and proteasome enzyme activities were increased at day 14. The alpha-sarcoglycan protein level was decreased immediately after exercise and at day 1, whereas the desmin level peaked at day 14. alphaB-crystallin and Hsp27 protein levels were increased at days 1 and 14. Our results suggest that the differential expression of calpain 2 and 3 mRNA levels may be important in the process of exercise-induced muscle damage, whereas expression of alpha-sarcoglycan, desmin, alphaB-crystallin and Hsp27 may be essentially involved in the subsequent remodelling of myofibrillar structure. This remodelling response may limit the extent of muscle damage upon a subsequent mechanical stress.
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PMID:Molecular adaptations of neuromuscular disease-associated proteins in response to eccentric exercise in human skeletal muscle. 1218

Limb girdle muscular dystrophies (LGMD) are a heterogeneous group of genetic disorders characterised by progressive weakness of the pelvic and shoulder girdle muscles and a great variability in clinical course. LGMD2A, the most prevalent form of LGMD, is caused by mutations in the calpain-3 gene (CAPN-3). More than 100 pathogenic mutations have been identified to date, however few genotype : phenotype correlation studies, including both DNA and protein analysis, have been reported. In this study we screened 26 unrelated LGMD2A Brazilian families (75 patients) through Single-Stranded Conformation Polymorphism (SSCP), Denaturing high-performance liquid chromatography (DHPLC) and sequencing of abnormal fragments which allowed the identification of 47 mutated alleles (approximately 90%). We identified two recurrent mutations (R110X and 2362-2363AG > TCATCT) and seven novel pathogenic mutations. Interestingly, 41 of the identified mutations (approximately 80%) were concentrated in only 6 exons (1, 2, 4, 5, 11 and 22), which has important implications for diagnostic purposes. Protein analysis, performed in 28 patients from 25 unrelated families showed that with exception of one patient (with normal/slight borderline reduction of calpain) all others had total or partial calpain deficiency. The effects of type of mutation, amount of calpain in the muscle, gender and ethnicity of affected patients on clinical course (age of onset and ascertainment) were analysed. Interestingly, it was observed that, on average, African-Brazilian calpainopathy patients are more severely affected than Caucasians.
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PMID:Clinical variability in calpainopathy: what makes the difference? 1246 90

Five affected siblings were referred with a probable diagnosis of proximal adult-type spinal muscular atrophy (SMA) based on lower motor neuron signs (muscle weakness and atrophy, hypotony, hypoactive or absent reflexes, and fasciculations), normal or borderline serum creatine kinase levels, and a neurogenic pattern on electromyography, compatible with motor neuron disease, in one patient. No exon 7-8 deletion in the survival motor neuron (SMN) gene was found. Linkage analysis excluded the SMN and all known autosomal recessive limb girdle muscular dystrophy loci, with the exception of LGMD-2A. A homozygous R769Q mutation in the calpain-3 gene and absence of muscle calpain-3 protein confirmed a calpainopathy. This family suggests that the clinical spectrum of calpainopathy might be broader and that this diagnosis might be considered in patients with an atypical motor neuron disease.
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PMID:Calpainopathy: how broad is the spectrum of clinical variability? 1464 90


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