Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10636 (tau protein)
 5,110 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 11 patients with distal myopathy with rimmed vacuole formation (DMRV), a well-known autosomal recessively inherited disorder, the rimmed vacuole formation appears to be the main pathological change accounting for the progressive muscle fiber degeneration. To gain a better understanding of the pathophysiology of the vacuole formation, we applied Congo red and immunohistochemical stains to muscle biopsies from these patients and the results were compared with those of patients with inclusion body myositis (IBM). The vacuoles in DMRV contained Congophilic amyloid material and deposits immunoreactive for beta-amyloid protein, both the NH2 and COOH termini of beta-amyloid protein precursor, ubiquitin, and tau protein. These results were similar to those seen in our present cases of IBM as well as in previously reported cases. Therefore, there may be no pathogenetic differences in the formation of rimmed vacuoles in DMRV and IBM. Nevertheless, the degenerative process involved in rimmed vacuole formation in various diseases may share a common pathogenetic mechanism with that in amyloid-plaque formation in Alzheimer's disease brain as has been proposed previously.
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PMID:Muscle fiber degeneration in distal myopathy with rimmed vacuole formation. 770 28

In various neuromuscular diseases, the most significant muscle degeneration is muscle fiber necrosis as seen in Duchenne muscular dystrophy (DMD). A certain membrane instability is probably responsible for muscle fiber necrosis, because defects in membrane proteins have been proposed to associate with progressive muscular dystrophies including dystrophin in DMD, a 50 KD subunit of dystrophin associated glycoprotein (DAG) in severe childhood autosomal recessive muscular dystrophy (SCARMD), and subunit M of laminin (merosin) in congenital muscular dystrophy and dy mouse. The vulnerable muscle surface membrane may permit extracellular calcium influx into the sarcoplasm resulting in focal myofibrillar hypercontraction (opaque fiber) and activation of proteases such as calpain and cathepsins. The muscle fiber then undergoes necrosis and allows macrophage invasion, followed by muscle fiber regeneration. Focal myofibrillar degeneration involving rimmed vacuole (RV) formation is an another striking muscle fiber degeneration seen in various neuromuscular diseases including inclusion body myositis (IBM) and distal myopathy with rimmed vacuole formation (DMRV). Abnormal accumulation of ubiquitin, beta-amyloid protein precursor and tau protein has been described in IBM by Askanas et al. The similar findings are also recognizable in DMRV and in an experimentally induced myopathy after long-term chloroquin administration to rat. Therefore, if we clarify the pathomechanism of degenerative process involved in the rimmed vacuole formation, the results may provide some insights into the understanding the process involved in amyloid plaque formation in Alzheimer's disease.
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PMID:[Muscle pathologic diagnosis--mechanism in muscle fiber degeneration]. 777 35

We immunostained muscle biopsies of 8 patients with sporadic inclusion body myositis (S-IBM), 7 patients with autosomal recessive hereditary inclusion body myopathy (H-IBM) (both diseases being characterized by similar muscle fiber vacuoles containing inclusions), and 11 normal and disease controls. We used the following well-characterized antibodies against tau protein: Tau-1, Alz-50, and anti-paired helical filament (PHF) antiserum. By light microscopy, in all S-IBM muscle biopsies virtually all vacuoles immunoreactive for ubiquitin and beta-amyloid protein also contained inclusions immunoreactive with Alz-50 and anti-PHF antiserum. With tau-1 antibody, strong immunoreactivity in the vacuoles was obtained only after dephosphorylation of muscle sections. By electronmicroscopy, all three antibodies immunodecorated exclusively cytoplasmic twisted tubulofilaments (TTFs). In H-IBM, virtually all ubiquitin and beta-amyloid-positive muscle fiber vacuoles contained inclusions immunoreactive with anti-PHF antiserum, but in only 40% of those fibers were the inclusions immunoreactive with Alz-50. In six H-IBM patients there were no tau-1 immunoreactive inclusions in any of their vacuolated muscle fibers; in one patient, 24% of the vacuolated fibers had tau-1 immunoreactivity. By demonstrating that hyperphosphorylated tau, which is characteristic of Alzheimer brain PHFs, is a component of S-IBM-muscle TTFs (which are also ultrastructurally similar to PHFs), our study: 1) provides the first demonstration of abnormally accumulated tau in nonneural tissue and 2) suggests that the cytopathogenesis in Alzheimer brain and S-IBM muscle may share some similar mechanisms. Whether the difference in tau immunoreactivity between S-IBM and most of the H-IBM patients reflects a difference in genetically determined transcriptional or posttranslational modifications of tau protein or other factors remains to be determined.
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PMID:Twisted tubulofilaments of inclusion body myositis muscle resemble paired helical filaments of Alzheimer brain and contain hyperphosphorylated tau. 829 7

To determine whether tau protein found in muscle fibers with rimmed vacuoles and in regenerating fibers was phosphorylated, we examined eight muscle biopsy samples containing rimmed vacuoles (from five patients with distal myopathy with rimmed vacuole formation and three patients with inclusion body myositis) and three muscle biopsy samples from patients with Duchenne muscular dystrophy containing numerous regenerating fibers. Although both rimmed vacuolated and regenerating fibers had increased immunoreactivity against tubulin and tau protein, tau protein in the former was more highly phosphorylated than that in the latter. While very few microtubules in muscle fibers with rimmed vacuoles were recognizable by electron microscopy, regenerating fibers, especially immature ones, contained numerous microtubules. Since tau protein found in vacuolated fibers is hyperphosphorylated, it can be considered to have reduced ability to bind tubulin molecules. Thus, the tau protein cannot stabilize microtubules, resulting in their depolymerization even in the presence of tubulin molecules.
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PMID:Tau protein immunoreactivity in muscle fibers with rimmed vacuoles differs from that in regenerating muscle fibers. 856 Sep 79

We review the newest advances related to seeking the pathogenic mechanism(s) of sporadic inclusion-body myositis (s-IBM) and present the pathologic diagnostic criteria of s-IBM. We discuss the possible pathogenic role of several themes, such as 1) increased amyloid-beta precursor protein (AbetaPP) and of its fragment Abeta; 2) phosphorylation of tau protein; 3) oxidative stress; 4) abnormal a) signal-transduction, b) transcription, and c) RNA accumulation; 5) "junctionalization" and myogenous" denervation; and 6) lymphocytic inflammation. Evidence is provided supporting our hypothesis that overexpression of AbetaPP within the aging muscle fibers is an early upstream event causing the subsequent pathogenic cascade. The remarkable pathologic similarities between s-IBM muscle and Alzheimer disease (AD) brain are discussed, and the possible cause and significance are addressed.
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PMID:Inclusion-body myositis: newest concepts of pathogenesis and relation to aging and Alzheimer disease. 1120 70

Sporadic inclusion body myositis (s-IBM) is the most frequent progressive acquired inflammatory myopathy in people older than 50 years. Abnormal aggregates of 'Alzheimer's proteins', including tau proteins, have been previously demonstrated in s-IBM. In the present study, we have investigated by immunohistochemistry and immunoblotting analysis the presence of tau proteins in muscle biopsy samples from patients with s-IBM and other myopathies with rimmed vacuoles, using newly developed antibodies raised against tau protein epitopes found in Alzheimer's disease brain. Tau immunoreactivity was shown in rimmed vacuoles or inclusions, preferentially with antibodies directed against phosphorylated carboxy-terminal epitopes of tau proteins. Cytoplasmic reactivity was also demonstrated in atrophic, nonvacuolated fibres, as well as in non-necrotic fibres invaded by inflammatory cells. Abnormally phosphorylated tau aggregates were also found in other compartments of the muscle fibre in s-IBM and other myopathies. Tau immunoblotting showed an electrophorectic profile of a doublet within the range of 60-62 kDa isovariants, which was different from tauopathies of the central nervous system. Finally, the unique pattern of immunoreactivity of s-IBM samples towards anti-tau antibodies is a new clue to a possible distinct subclass of peripheral tauopathy, different from the tauopathies of the central nervous system.
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PMID:Tau aggregates are abnormally phosphorylated in inclusion body myositis and have an immunoelectrophoretic profile distinct from other tauopathies. 1554 Oct 3

We investigated whether beta-amyloid and tau protein are involved in the formation of inclusion body myositis (IBM)-like inclusions found in children with rimmed vacuoles and congenitally affected muscles. We immunostained muscle biopsy specimens from four children and one 18-year-old boy with congenital myopathy containing rimmed vacuoles and IBM-like inclusions with antibodies against beta-amyloid, tau protein and ubiquitin. Focal accumulations of both beta-amyloid and phosphorylated tau coexisted with tubulofilamentous structures in all cases. Our studies demonstrate for the first time that the full morphological phenotype of IBM including beta-amyloid and tau protein deposits may also develop in children, and that congenital, probably genetic, muscle defects may lead to abnormal protein aggregation in IBM-like inclusions.
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PMID:Rimmed vacuoles with beta-amyloid and tau protein deposits in the muscle of children with hereditary myopathy. 1678 22

Inclusion body myositis and Alzheimer's disease are age-related disorders characterized in part by the appearance of intracellular lesions composed of filamentous aggregates of the microtubule-associated protein tau. Abnormal tau phosphorylation accompanies tau aggregation and may be an upstream pathological event in both diseases. Enzymes implicated in tau hyperphosphorylation in Alzheimer's disease include members of the casein kinase 1 family of phosphotransferases, a group of structurally related protein kinases that frequently function in tandem with the ubiquitin modification system. To determine whether casein kinase 1 isoforms associate with degenerating muscle fibers of inclusion body myositis, muscle biopsy sections isolated from sporadic disease cases were subjected to double-label fluorescence immunohistochemistry using selective anti-casein kinase 1 and anti-phospho-tau antibodies. Results showed that the alpha isoform of casein kinase 1, but not the delta or epsilon isoforms, stained degenerating muscle fibers in all eight inclusion body myositis cases examined. Staining was almost exclusively localized to phospho-tau-bearing inclusions. These findings, which extend the molecular similarities between inclusion body myositis muscle and Alzheimer's disease brain, implicate casein kinase 1 alpha as one of the phosphotransferases potentially involved in tau hyperphosphorylation.
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PMID:Casein kinase 1 alpha associates with the tau-bearing lesions of inclusion body myositis. 1819 Oct 26

TDP43 protein mislocalization is a hallmark of the neurodegenerative diseases amyotrophic lateral sclerosis and frontotemporal dementia, and mutations in the gene encoding TDP43 cause both disorders, further highlighting its role in disease pathogenesis. TDP43 is a heterogenous ribonucleoprotein, therefore suggesting that alterations in RNA metabolism play a role in these disorders, although direct evidence in patients is lacking. Sporadic inclusion body myositis (sIBM) is the most common acquired myopathy occurring in adults aged older than 50 years and abnormal cytoplasmic accumulations of TDP43 have been consistently described in sIBM myofibers. Here, we exploit high quality RNA from frozen sIBM muscle biopsies for transcriptomic studies on TDP43-proteinopathy patient tissue. Surprisingly, we found widespread sIBM-specific changes in the RNA metabolism pathways themselves. Consistent with this finding, we describe novel RNA binding proteins to mislocalize in the cytoplasm of sIBM myofibers and splicing changes in MAPT, a gene previously shown to play a role in sIBM. Our data indicate widespread alterations of RNA metabolism are a novel aspect of disease pathogenesis in sIBM. These findings also document an association, in TDP43-proteinopathy patients, between heterogenous ribonucleoprotein pathology and RNA metabolism alterations and carry importance for neurodegenerative diseases, such as amyotrophic lateral sclerosis and frontotemporal dementia.
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PMID:Widespread RNA metabolism impairment in sporadic inclusion body myositis TDP43-proteinopathy. 2446 17

The number of known pathologies involving deregulated Tau expression/metabolism is increasing. Indeed, in addition to tauopathies, which comprise approximately 30 diseases characterized by neuronal aggregation of hyperphosphorylated Tau in brain neurons, this protein has also been associated with various other pathologies such as cancer, inclusion body myositis, and microdeletion/microduplication syndromes, suggesting its possible function in peripheral tissues. In addition to Tau aggregation, Tau deregulation can occur at the expression and/or splicing levels, as has been clearly demonstrated in some of these pathologies. Here, we aim to review current knowledge regarding the regulation of human MAPT gene expression at the DNA and RNA levels to provide a better understanding of its possible deregulation. Several aspects, including repeated motifs, CpG island/methylation, and haplotypes at the DNA level, as well as the key regions involved in mRNA expression and stability and the splicing patterns of different mRNA isoforms at the RNA level, will be discussed.
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PMID:Regulation of human MAPT gene expression. 2617 22


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