Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Corticobasal syndrome is characterized by cortical dysfunction and L-dopa-unresponsive Parkinsonism, with asymmetrical onset of clinical presentation and evidence of atrophy and/or hypometabolism at neuroimaging. Recently, the heterogeneous pathologic substrate of corticobasal syndrome has been further expanded to include cases with pathologic diagnosis of frontotemporal lobar degeneration with ubiquitin/TDP-43 (TAR DNA binding protein 43)-positive inclusions associated with progranulin (PGRN) mutations. We report a family in which several individuals have been affected with a dementia/movement disorder phenotype. The proband presented at age 45 with spontaneous left arm levitation, ideational apraxia, asymmetric parkinsonism, and dystonia. Subsequently, he developed limb-kinetic apraxia, left-side hemineglect, memory loss, and executive dysfunction. Magnetic resonance imaging and [F]fluorodeoxyglucose-positron emission tomography studies revealed severe cerebral cortical atrophy and hypometabolism, which were significantly more pronounced in the parietal lobes (right > left). Neuropathologic examination displayed the highest degree of degeneration and ubiquitin/TDP-43 pathology in the proband's parietal areas. Genetic analysis revealed the presence of the c.26C>A PGRN mutation in 1 allele. This mutation has been reported in association with hereditary-dysphasic-disinhibition-dementia, Alzheimer-like dementia, progressive supranuclear palsy, and primary progressive aphasia. The peculiar findings observed in this patient indicate that the parietal lobe may represent the most vulnerable anatomical area in some of the PGRN-associated frontotemporal lobar degeneration with ubiquitin/TDP-43-positive inclusion cases.
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PMID:Corticobasal syndrome associated with the A9D Progranulin mutation. 1791 83

Mutations in the progranulin gene (GRN) are a major cause of frontotemporal lobar degeneration with ubiquitin-positive, tau-negative inclusions (FTLD-U) but the distinguishing clinical and anatomical features of this subgroup remain unclear. In a large UK cohort we found five different frameshift and premature termination mutations likely to be causative of FTLD in 25 affected family members. A previously described 4-bp insertion mutation in GRN exon 2 comprised the majority of cases in our cohort (20/25), with four novel mutations being identified in the other five affected members. Additional novel missense changes were discovered, of uncertain pathogenicity, but deletion of the entire gene was not detected. The patient collection was investigated by a single tertiary referral centre and is enriched for familial early onset FTLD with a high proportion of patients undergoing neuropsychological testing, MRI and eventual neuropathological diagnosis. Age at onset was variable, but four mutation carriers presented in their 40s and when analysed as a group, the mean age at onset of disease in GRN mutation carriers was later than tau gene (MAPT) mutation carriers and duration of disease was shorter when compared with both MAPT and FTLD-U without mutation. The most common clinical presentation seen in GRN mutation carriers was behavioural variant FTLD with apathy as the dominant feature. However, many patients had language output impairment that was either a progressive non-fluent aphasia or decreased speech output consistent with a dynamic aphasia. Neurological and neuropsychological examination also suggests that parietal lobe dysfunction is a characteristic feature of GRN mutation and differentiates this group from other patients with FTLD. MR imaging showed evidence of strikingly asymmetrical atrophy with the frontal, temporal and parietal lobes all affected. Both right- and left-sided predominant atrophy was seen even within the same family. As a group, the GRN carriers showed more asymmetry than in other FTLD groups. All pathologically investigated cases showed extensive type 3 TDP-43-positive pathology, including frequent neuronal cytoplasmic inclusions, dystrophic neurites in both grey and white matter and also neuronal intranuclear inclusions. Finally, we confirmed a modifying effect of APOE-E4 genotype on clinical phenotype with a later onset in the GRN carriers suggesting that this gene has distinct phenotypic effects in different neurodegenerative diseases.
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PMID:A distinct clinical, neuropsychological and radiological phenotype is associated with progranulin gene mutations in a large UK series. 1823 97

Frontotemporal degeneration (FTD), formerly known as Pick's disease has become recognized as a distinct and relatively common entity encompassing behavioural (bvFTD language (PPA) and extrapyramidal (CBD/PSP) presentations. Further clinical subdivisions such as semantic dementia(SD), and pathological subtypes such as mesial temporal sclerosis increase the complexity of diagnosis.The relatively younger age of onset, the typical presentations of syndromes and focal asymmetrical frontotemporal atrophy on imaging allows experienced clinicians to make the diagnosis confidently as long as the overlap between the syndromes is recognized. There is also an overlap with ALS pathologically and clinically. The underlying histology in FTD/Pick complex is ubiquitin positive tau and synuclein negative neuronal inclusions (FTLD-U) in more than half of autopsies and tau positive CBD/PSP/ Pick bodies (FTLD-T) in the rest. The clinical syndromes of bvFTD and SD are likely associated with FTLD-U and PPA/CBDS/PSP with FTLD-T, but there is too much overlap to predict the pathology from the clinical syndromes reliably. The ubiquitin-tau pathological dichotomy is best considered under the Pick complex umbrella to allow for the significant overlap. So far trazodone in behavior and galantamine in aphasia had symptomatic benefit in small trials and SSRI-sand antipsychotics in uncontrolled reports were used as symptomatic therapies. Recent discoveries of tau and progranulin (in the ubiquitin-positive cases) mutations on chromosome 17 and other mutations on chromosome 3 and 9 in the high incidence of autosomal dominant families and a common protein abnormality, the TDP-43 in FTLD-U and ALS are likely to be important in finding therapeutic targets.
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PMID:Clinical features and diagnosis of frontotemporal dementia. 1918 72

Neural network breakdown is a key issue in neurodegenerative disease, but the mechanisms are poorly understood. Here we investigated patterns of brain atrophy produced by defined molecular lesions in the two common forms of genetically mediated frontotemporal lobar degeneration (FTLD). Nine patients with progranulin (GRN) mutations and eleven patients with microtubule-associated protein tau (MAPT) mutations had T1 MR brain imaging. Brain volumetry and grey and white matter voxel-based morphometry (VBM) were used to assess patterns of cross-sectional atrophy in the two groups. In a subset of patients with longitudinal MRI rates of whole-brain atrophy were derived using the brain-boundary-shift integral and a VBM-like analysis of voxel-wise longitudinal volume change was performed. The GRN mutation group showed asymmetrical atrophy whereas the MAPT group showed symmetrical atrophy. Brain volumes were smaller in the GRN group with a faster rate of whole-brain atrophy. VBM delineated a common anterior cingulate-prefrontal-insular pattern of atrophy in both disease groups. Additional disease-specific profiles of grey and white matter loss were identified on both cross-sectional and longitudinal imaging: GRN mutations were associated with asymmetrical inferior frontal, temporal and inferior parietal lobe grey matter atrophy and involvement of long intrahemispheric association white matter tracts, whereas MAPT mutations were associated with symmetrical anteromedial temporal lobe and orbitofrontal grey matter atrophy and fornix involvement. The findings suggest that the effects of GRN and MAPT mutations are expressed in partly overlapping but distinct anatomical networks that link specific molecular dysfunction with clinical phenotype.
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PMID:Distinct profiles of brain atrophy in frontotemporal lobar degeneration caused by progranulin and tau mutations. 2004 77

Frontotemporal lobar degeneration (FTLD) refers to a clinically, pathologically, and genetically heterogeneous group of dementias that arises from the degeneration of the frontal and temporal lobes. Mutations in the progranulin gene (GRN) are a major cause of FTLD with TDP-43 inclusions. Herein, we describe the clinical, neuropathological, and genetic findings in a case of autosomal dominant behavioral variant of frontotemporal dementia (bvFTD) with asymmetrical parkinsonism and prominent visuospatial deficits that carries a novel GRN mutation. This case highlights important clinical characteristics that seem to be common in FTLD GRN-associated patients, such as asymmetrical parkinsonism and parietal symptoms, and that are correlated to the pathological involvement of striatum (rather than substantia nigra in our case) and parietal lobe. We also emphasize that plasma progranulin level can be useful to infer about the pathogenicity of new GRN mutations.
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PMID:Clinical, neuropathological, and genetic characteristics of the novel IVS9+1delG GRN mutation in a patient with frontotemporal dementia. 2236 70

Frontotemporal lobar degeneration (FTLD) describes a spectrum of clinically, pathologically and genetically heterogeneous neurodegenerative disorders of unknown aetiology. FTLD spectrum disorders collectively represent a leading cause of early-onset dementia, with most cases presenting between 45 and 64 years of age. FTLD is characterized by progressive changes in behaviour, executive dysfunction and/or language impairment and can be differentiated clinically into three frontotemporal dementia (FTD) syndromes as follows: (i) behavioural variant (bvFTD); (ii) semantic dementia (SD); and (iii) progressive nonfluent aphasia (PNFA). Additionally, there is a significant clinical, pathological and genetic overlap between FTD and motor neuron disease/amyotrophic lateral sclerosis (FTD-ALS) and the atypical parkinsonian syndromes, progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). bvFTD is characterized by progressive behavioural impairment and a decline in executive function with frontal lobe-predominant atrophy, SD by a loss of object knowledge with prominent anomia and asymmetrical atrophy of the anterior temporal lobes and PNFA by expressive or motor speech deficits with predominantly left peri-sylvian atrophy. Recent advances in molecular biology and immunohistochemical staining techniques have further classified the FTLD spectrum disorders based upon the predominant neuropathological protein into three main categories: (i) microtubule-associated protein tau (FTLD-TAU); (ii) TAR DNA-binding protein-43 (FTLD-TDP); and (iii) fused in sarcoma protein (FTLD-FUS). Up to 40% of FTD patients report a family history of neurodegenerative illness, and one-third to one-half of familial cases of FTD follow an autosomal dominant inheritance pattern. Mutations in MAPT, PGRN, TARDBP, VCP and CHMP2B have been described, along with a recently identified C9ORF72 hexanucleotide repeat expansion. To date, there are no US FDA-approved treatments or disease-modifying therapies for FTD. Pharmacological strategies have focused on neurotransmitter replacement and modulation for the treatment of behavioural, motor and cognitive symptoms of FTD, and include selective serotonin reuptake inhibitors (SSRIs), atypical antipsychotics, acetylcholinesterase inhibitors and glutamate NMDA receptor antagonists. At present, adequate management of FTD symptoms involves a combination of pharmacological therapy with behavioural, physical and environmental modification techniques.
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PMID:Frontotemporal lobar degeneration: epidemiology, pathology, diagnosis and management. 2295 Apr 90

White matter hyperintensities (WMH) are often seen on MRI brain scans in frontotemporal dementia (FTD) due to progranulin (GRN) mutations, but their pathological correlates are unknown. We examined the histological changes underlying WMH in a patient with GRN mutation associated behavioral variant FTD. In vivo and cadaveric MRI showed progressive, asymmetric frontotemporal and parietal atrophy, and asymmetrical WMH predominantly affecting frontal mid-zones. We first performed segmentation and localization analyses of WMH present on cadaveric MRI FLAIR images, then selected five different brain regions directly matched to differing severities of WMH for histological analysis. We used immunohistochemistry to assess vascular pathology, degree of spongiosis, neuronal and axonal loss, TDP-43, demyelination and astrogliosis, and microglial burden and morphology. Brain regions with significant WMH displayed severe cortical and white matter pathology, and prominent white matter microglial activation and microglial dystrophy, but only mild axonal loss and minimal vascular pathology. Our study suggests that WMH in GRN mutation carriers are not secondary to vascular pathology. Whilst cortical pathology induced axonal degeneration could contribute to white matter damage, individuals with GRN mutations could develop selective white matter vulnerability and myelin loss due to chronic, regional microglial dysfunction arising from GRN haploinsufficiency.
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PMID:Pathological correlates of white matter hyperintensities in a case of progranulin mutation associated frontotemporal dementia. 3011 57