Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Neurofibrillary Tangles”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

Evidence for early vulnerability of the medial and inferior aspects of the temporal lobe in an 82-year-old patient with preclinical signs of dementia. Regional and laminar distribution of neurofibrillary tangles and senile plaques.

Detailed neuropathologic studies of neurofibrillary tangle and senile plaque distribution have shown that key elements of certain neocortical and hippocampal circuits are either compromised or lost in Alzheimer's disease. It has been suggested that a global corticocortical disconnection underlies dementia and leads to the dramatic disruption of integrated functions exhibited by patients with Alzheimer's disease. To investigate the distribution of lesions associated with the earliest indications of incipient dementia, we performed a quantitative neuropathologic evaluation of a non-demented 82-year-old patient demonstrating globally intact intellectual function but initial signs of impairment of specific cognitive functions before death. We observed densities of senile plaques comparable to those found in Alzheimer's disease throughout the cerebral cortex, whereas extensive neurofibrillary tangle formation was restricted to selective areas of the temporal lobe. The results of this systematic quantitative and comparative analysis of medial and inferior temporal lobe structures suggest a functional relationship between the degree of cognitive decline evidenced in the earliest stages of Alzheimer's disease and the anatomic progression of Alzheimer's disease-related pathologic changes along specific elements of the cortical circuitry.

Aged↗

Ubiquitin is a component of neurofibrillary tangles in a variety of neurodegenerative diseases.

Ubiquitin has been shown to be a component of neurofibrillary tangles in Alzheimer's disease. We now show immunocytochemically that it is also a component of neurofibrillary tangles in several other neurodegenerative diseases of diverse aetiology, including Down's syndrome, dementia pugilistica and postencephalitic parkinsonism, and in normal ageing. Ubiquitin immunoreactivity is not, however, generally found in the neurofibrillary tangles of progressive supranuclear palsy. These findings show that while associated ubiquitin is not a feature unique to the tangles of Alzheimer's disease, it is not simply a non-specific response to the presence of an inclusion body within the cell. The observations suggest that ubiquitin may have an important role in the formation of neurofibrillary tangles in a variety of neurodegenerative diseases.

Alzheimer Disease↗

Neurofibrillary tangles mediate the association of amyloid load with clinical Alzheimer disease and level of cognitive function.

OBJECTIVE: To test the hypothesis that the association of amyloid load with clinical Alzheimer disease (AD) and cognitive impairment is mediated through neurofibrillary tangles. DESIGN: Longitudinal clinicopathologic cohort study. PARTICIPANTS AND SETTING: Forty-four individuals with clinically diagnosed AD and 53 without dementia who participated in the Religious Orders Study underwent a uniform structured clinical evaluation for AD and cognitive testing about 8 months prior to death, and brain autopsy at death. METHODS: The percent area occupied by amyloid-beta and the density of neurofibrillary tangles were quantified from 6 brain regions and averaged to yield summary measures of amyloid load and neurofibrillary tangles. Multivariate regression analyses were used to simultaneously examine the effects of amyloid load and neurofibrillary tangles on clinically diagnosed AD and level of cognition. MAIN OUTCOME MEASURES: Clinically diagnosed AD and level of global cognitive function proximate to death. RESULTS: In separate logistic regression analyses, each 1% increase in amyloid load was associated with about a 50% increase in the odds of clinical AD (P =.002), and each neurofibrillary tangle was associated with a greater than 20% increase in the odds of clinical AD (P<.001). When a term for tangles was added to the regression model with amyloid, the association of amyloid load with clinical disease was reduced by more than 60% and was no longer significant, whereas the association of tangles with clinical disease was essentially unchanged. Similar results were found in analyses of global cognitive function. CONCLUSION: These findings are consistent with a sequence of pathologic events whereby the effect of amyloid deposition on clinical disease is mediated by neurofibrillary tangles.

Aged↗

Neurofibrillary tangles in Alzheimer's disease and progressive supranuclear palsy: antigenic similarities and differences. Microtubule-associated protein tau antigenicity is prominent in all types of tangles.

The antigenic profile of neurofibrillary tangles (NFT) in Alzheimer's disease (AD), senile dementia of Alzheimer type (SDAT), progressive supranuclear palsy (PSP) and in non-demented aged humans was investigated by light and electron microscopic immunocytochemistry using antisera and monoclonal antibodies to tubulin, microtubule-associated proteins (MAP1, MAP2 and tau), neurofilament proteins and determinants unique to Alzheimer paired helical filaments (PHF). Antibodies to tau proteins labeled NFT in all cases investigated (AD, SDAT, PSP and non-demented aged humans). However, one monoclonal antibody to PHF recognized numerous tangles in AD/SDAT, but only a small minority of the PSP tangles. Antibodies to tubulin, MAP1, MAP2 and neurofilament proteins did not selectively stain NFT. Whereas pretreatment of sections with phosphatase was required for the detection of tangles with Tau-1 monoclonal antibody, digestion of sections with either phosphatase or pronase had no significant effect on the staining pattern obtained with the other antibodies. Our studies show that, as previously described for AD/SDAT, phosphorylated tau polypeptides are also a major antigenic determinant of tangles in PSP, indicating that tangle formation may follow a common pathogenetic pathway in neurofibrillary degenerations. There is, however, at least one epitope in AD/SDAT tangles which seems to be absent on, or at least inaccessible in, the 15-nm straight fibrils of PSP.

Adult↗

Rapid neurofibrillary tangle formation after localized gene transfer of mutated tau.

Neurofibrillary pathology was produced in the brains of adult rats after localized gene transfer of human tau carrying the P301L mutation, which is associated with frontotemporal dementia with parkinsonism. Within 1 month of in situ transfection of the basal forebrain region of normal rats, tau-immunoreactive and argyrophilic neuronal lesions formed. The fibrillar lesions had features of neurofibrillary tangles and tau immunoreactivity at light and electron microscopic levels. In addition to neurofibrillary tangles, other tau pathology, including pretangles and neuropil threads, was abundant and widespread. Tau gene transfer to the hippocampal region of amyloid-depositing transgenic mice produced pretangles and threads, as well as intensely tau-immunoreactive neurites in amyloid plaques. The ability to produce neurofibrillary pathology in adult rodents makes this a useful method to study tau-related neurodegeneration.

Animals↗

Variabilities in the distribution of neurofibrillary tangles in the anterior parahippocampal gyrus at initial stages of Alzheimer's disease.

The entorhinal region is located in the ventromedial surface of the temporal lobe on the parahippocampal gyrus. Occurrence of early argyrophilic neurofibrillary tangles was investigated in brain sections of the left and right entorhinal region of 9 individuals of both sexes between the age of 26 to 54 years. Parasagittal serial sections at 100 microns were performed to include the very anterior part of the entorhinal region. An advanced silver method was used for staining neurofibrillary changes. The neurofibrillary tangles were counted via light microscopy, marked on the sections and staged as proposed by Braak and Braak. In 1 case we found a left-right difference by 1 stage (right: stage I, left: stage II). The tangle distribution in another case exhibited several neurofibrillary tangles only in the very anterior part of the entorhinal cortex on both sides (stage 0). In 3 cases some neurofibrillary tangles occurred in the very anterior part of the right entorhinal region, while a few are present in more posterior parts (stage I). The corresponding left hemisphere showed the same anterior-posterior distribution pattern as on the right in only 1 of these cases. In the remaining 4 cases, no neurofibrillary changes were visible. In conclusion, the very anterior part of the entorhinal region is among the earliest sites for development of neurofibrillary tangles. Distribution of early Alzheimer-related neurofibrillary changes in the entorhinal region displays variabilities in the anterior-posterior direction as well as in a left-right comparison.

Adult↗

Aluminum neurotoxicity--potential role in the pathogenesis of neurofibrillary tangle formation.

Alzheimer's disease is a progressive neurodegenerative disease characterized neuropathologically by the development of large numbers of neurofibrillary tangles in certain neuronal populations of affected brains. This paper presents a review of the available evidence which suggests that aluminum is associated with Alzheimer's disease and specifically with the development of the neurofibrillary tangle. Aluminum salts inoculated into experimental animals produce neurofilamentous lesions which are similar, though not identical, to the neurofibrillary tangle of man. Although a few reports have suggested evidence of increased amounts of aluminum in the brains of Alzheimer's disease victims, such bulk analysis studies have been difficult to replicate. Using scanning electron microscopy with x-ray spectrometry, we have identified accumulations of aluminum in neurofibrillary tangle-bearing neurons of Alzheimer's disease. Similar accumulations have been identified in the neurofibrillary tangle-bearing neurons found in the brains of indigenous natives of Guam who suffer from parkinsonism with dementia and amyotrophic lateral sclerosis. This ongoing research still cannot ascribe a causal role of aluminum in the pathogenesis of neurofibrillary tangle formation; however, it does suggest that environmental factors may play an important part in the formation of this abnormality.

Aluminum↗

Ultrastructure of neurofibrillary tangles in progressive supranuclear palsy.

Ultrastructure of neurofibrillary tangles was investigated on the subcortical neurons of an autopsy case of progressive supranuclear palsy. The patient was a 64-year-old female and suffered from her illness for 9 years. Two kinds of ultrastructure were observed in the subcortical neurofibrillary tangles, i.e. that 150 A straight tubules and the 220 A twisted tubules. They appeared separately in each neuron and a transition between these two structures could not be remarked. Besides, a few particles with a paracrystalline hexagonal structure were observed in some subcortical neurons.

Brain↗

Activation mechanism of brain microglia in patients with diffuse neurofibrillary tangles with calcification: a comparison with Alzheimer disease.

Diffuse neurofibrillary tangles with calcification (DNTC) is an atypical dementia and is characterized pathologically by diffuse neurofibrillary tangles (NFTs) without senile plaques (SPs). In this study, we investigated the distribution of human leukocyte antigen (HLA)-DR-positive activated microglia in postmortem brain tissue of six patients with DNTC and six patients with Alzheimer disease (AD). HLA-DR-positive activated microglia were observed to associate with SPs in AD. In the DNTC brain, which lacks SPs, HLA-DR-positive microglia were mainly accumulated around weakly tau-positive NFTs, which were also positive for anti-amyloid-P and anti-C3d antibodies. The results of this study suggest that the complement pathway is also activated in the DNTC brain and that immune and inflammatory responses, including microglia activation, may occur around extracellular NFTs in DNTC patients.

Aged↗

Neuronal loss correlates with but exceeds neurofibrillary tangles in Alzheimer's disease.

To assess the relationship between dementia, neuronal loss, and neuropathological findings in Alzheimer's disease (AD), we counted the number of neurons, senile plaques, and neurofibrillary tangles in a high-order association cortex. We studied the superior temporal sulcus of 34 individuals with AD and 17 nondemented control subjects, using statistically unbiased, stereological counting techniques. The number of superior temporal sulcus neurons in nondemented control subjects was stable across the sixth to ninth decades. In AD, more than 50% of the neurons were lost. Both neuronal loss and neurofibrillary tangles increased in parallel with the duration and severity of illness, but the amount of neuronal loss exceeded by manyfold the amount of neurofibrillary tangles accumulated. In contrast to the correlation between neurofibrillary tangles and neuronal loss, the number of senile plaques and the percentage of the superior temporal sulcus that was covered by Abeta (amyloid burden) were not related to neuronal loss, number of neurofibrillary tangles, or duration of disease. Neither the amount nor the rate of neuronal loss in the superior temporal sulcus in AD correlated with apolipoprotein E genotype. These data suggest that neuronal loss in association areas such as the superior temporal sulcus contributes directly to cognitive impairment in AD.

Aged↗

Quantitative analysis of neurofibrillary pathology in a general population to reappraise neuropathological criteria for senile dementia of the neurofibrillary tangle type (tangle-only dementia): the Hisayama Study.

Senile dementia of the neurofibrillary tangle type (SD-NFT) is characterized by numerous neurofibrillary tangles (NFT) in the hippocampal region and the absence or minimal presence of senile plaques throughout the brain. We analyzed 207 demented subjects and 68 non-demented subjects autopsied in the Hisayama study to investigate the clinicopathological aspects of SD-NFF in the general Japanese population. The prevalence of SD-NFT in the consecutive autopsy cases was 8/207 (3.9%), comprising three men and five women. The average age at onset and death was 83.8 +/- 6.8 (mean +/- SD; standard deviation) and 88.1 +/- 7.6 years, respectively. A mild memory disturbance preceded a decrease in the ability to undertake the activities of daily living and the diagnosis of dementia. Focal cerebral symptoms, such as aphasia and paralysis, did not appear during the disease course of any subject. Gross examination of the brains showed moderate to severe diffuse cerebral atrophy with brain weight loss (mean +/- SD; standard deviation: 1118.1 +/- 124.0 g). Histologically, there were abundant NFT and neuropil threads predominantly in or limited to the limbic cortex. The density of NFT in the CA1/subiculum in SD-NFT was much higher than the densities in the other hippocampal regions. The average density of NFT in CA1 in SD-NFT subjects was 115.4 per 100 x field (range 23-247), that in Alzheimer disease (AD) subjects was 80.1 (range 1-227), and that in non-demented elderly subjects was 37.2 (range 0-203). Although many previous papers have reported that the densities of NFT in the limbic system in SD-NFT were significantly higher than those in AD, there was considerable overlap of NFT densities in CA1 among the non-demented elderly, AD subjects and SD-NFT subjects.

Aged↗

[An autopsy case of "diffuse neurofibrillary tangles with calcification", multiple infarctions and hyaline arteriosclerosis].

"Diffuse neurofibrillary tangles with calcification (DNTC)" is a slowly progressive form of presenile dementia characterized by localized temporal atrophy, pronounced calcareous deposits and numerous neurofibrillary tangles (NFTs) without senile plaques. We report a 70-year-old woman with DNTC, multiple infarctions and hyaline arteriosclerosis. This case was clinically characterized by persistent delusional ideas and personality changes. Intellectual deterioration was mild, and no focal manifestations were noted. Neuropathologically, numerous NFTs were seen distributed primarily in the hippocampal region, and massive calcareous deposits were observed in the cerebrum, basal ganglia and cerebellum. There were no senile plaques. Although the findings in this case were compatible with a diagnosis of DNTC, certain additional findings were also noted. The first was the presence of multiple infarctions in the basal ganglia and hyaline arteriosclerosis. Although these lesions may have been induced by hypertension, our review of previous reports of DNTC revealed a high incidence of arteriosclerosis. The second was the absence of lobar atrophy, which may have been due to the cerebral edema caused by the subdural hemorrhage or related to the relatively short duration of the illness. The dilatation of the temporal horn of the lateral ventricle and prominent NFTs in the hippocampal region indicate the initial occurrence of the disease in this region.

Aged↗

Tau pathology in diffuse neurofibrillary tangles with calcification (DNTC): biochemical and immunohistochemical investigation.

Diffuse neurofibrillary tangles with calcification (DNTC) represents a primary and sporadic presenile dementia that is characterized by temporal or fronto-temporal atrophy with diffuse neurofibrillary tangles (NFTs), neuropil threads and Fahr-type calcification without senile plaques. We examined the tau pathology in five autopsy cases of DNTC by immunoblotting and immunohistochemistry using phosphorylation-dependent and -independent anti-tau antibodies. The pattern of staining for different epitopes of beta-amyloid (A beta) was also investigated. NFTs were immunopositive with all the anti-tau antibodies used in this study. On the immunoblots, sarkosyl-insoluble tau appeared as three major bands of 60, 64 and 68 kDa, and as a minor band at 72 kDa. The majority of extracellular NFTs were weakly immunopositive only with the antibody recognizing the 40 carboxyl-terminal of A beta in DNTC. These results suggest that Alzheimer's disease-like tau pathology could exist independently of A beta deposits in DNTC.

Aged↗

Progressive neuronal DNA damage associated with neurofibrillary tangle formation in Alzheimer disease.

DNA damage, as demonstrated by in situ Tdt-mediated dUTP-X-nick end labeling (TUNEL), is widespread in the cerebral cortex in end-stage Alzheimer disease, but has not been previously correlated with stages of neurofibrillary tangle formation. To assess possible relationships between neurofibrillary tangle formation and DNA damage, we used tau immunohistochemistry and TUNEL in tangle-rich fields of tissue sections of subiculum and parahippocampal cortex tissue from 12 Alzheimer and 6 control patients. Structures were classified and quantified as tau-/TUNEL-, tau-/TUNEL+, tau+/TUNEL-, or tau+/TUNEL+. Tau+ structures were subclassified into 4 stages (0-3) based on neurofibrillary tangle morphology. The total number of TUNEL+ neurons was significantly less in control than in Alzheimer patients (35 +/- 7.2 vs 90 +/- 9.3/mm2; mean +/- SEM; p < 0.05). The number of tau+/TUNEL+ neurons (40 +/- 1/mm2) was less than that of tau-/TUNEL- neurons (68 +/- 7/mm2) or tau-/TUNEL+ neurons in the same fields (50 +/- 4/mm2, p < 0.0001). Tau+/TUNEL- structures were fewer in number (21 +/- 1/mm2), with a third of these representing acellular "ghost tangles" (stage 3). Tau+ neurons were more likely than tau- neurons to be TUNEL+ (64 +/- 6% vs 44 +/- 2%; mean +/- SEM; p < 0.01), although most TUNEL+ neurons were tau-, even in these selected, tangle-rich fields. TUNEL positivity was not uniformly distributed among tangle stages. TUNEL positivity was less common among early (stage 0) tangles than in tau neurons (21 +/- 6% vs 44 +/- 2%; p < 0.001), but this rose to 53% among intermediate (stage 1) tangles, and to 87% among late (stage 2) tangles. We suggest that early stages of neurofibrillary tangle formation occur in a subpopulation of relatively healthy (TUNEL-) neurons, and that tangle progression is accompanied by increasing neuronal morbidity.

Aged↗

Association of cholinesterases with amyloid in extracellular neurofibrillary tangles.

Double-labeling techniques conclusively demonstrated that extracellular neurofibrillary tangles immunoreactive for beta protein were also positive for cholinesterases. Ultrastructurally, cholinesterases decorated bundles of amyloid-like filaments, which appeared intermingled with straight filaments and cellular processes. A lighter labeling of esterases was also seen over most straight filaments. These observations extend the consistent association of cholinesterases with fibrillary beta-amyloid protein to a new location in neurofibrillary tangles.

Aged↗

Neurofibrillary tangles of Alzheimer disease share antigenic determinants with the axonal microtubule-associated protein tau (tau)

The relationship of the neurofibrillary tangle, found in Alzheimer disease and aged brains, to normal or abnormal cytoskeletal proteins remains elusive. Although immunohistochemical studies have yielded disparate results, most antigenic determinants localized to neurofibrillary tangles are cytoskeletal constituents normally present in neuronal perikarya or dendrites. We report light and electron microscopic immunolabeling of neurofibrillary tangles by a monoclonal antibody to the microtubule-associated protein tau (tau). Dephosphorylation of tissue slices not only increased the number of tau-positive tangles but also produced marked positive immunoreactivity of neuritic plaques. The localization of tau, an axonal protein, to neurofibrillary tangles in the perikaryon in particular suggests that abnormal synthesis, modification, or aggregation of tau may induce aberrant cytoskeletal--cell organelle interactions, subsequent interference with axonal flow, and resultant tangle formation.

Alzheimer Disease↗

Increased tau phosphorylation but absence of formation of neurofibrillary tangles in mice double transgenic for human tau and Alzheimer mutant (M146L) presenilin-1.

Neurofibrillary tangles, composed of tau proteins, are a key lesion observed in sporadic forms of Alzheimer's disease and in familial forms associated with mutations of presenilin-1 (PS1). We have generated a double transgenic mouse line expressing a human tau isoform and a mutated form of PS1 (M146L) in neurons. Increased expression of the PS1 holoprotein was observed in the tau/PS1 transgenic mice and the proteolytic fragments of PS1 did not appear to be modified. A somatodendritic accumulation of the transgenic tau and an increase in tau phosphorylation were observed in both tau- and tau/PS1 transgenic mice. Neurofibrillary tangles were not observed in animals analyzed up to 17 months. Immunoprecipitation of tau from brain homogenates demonstrated its binding with active glycogen synthase kinase-3beta in control, tau- and tau/PS1 transgenic lines. These results suggest that overexpression of this Alzheimer mutant PS1 in vivo is not by itself sufficient to induce the formation of neurofibrillary tangles, even in neurons co-expressing and accumulating a human tau isoform.

Alzheimer Disease↗

Alzheimer neurofibrillary tangles contain phosphorylated and hidden neurofilament epitopes.

Three monoclonal antibodies to neurofilaments (RT97, BF10 and 147), two of which also recognised neurofibrillary tangles (RT97 and BF10), have all been shown to be specific for phosphorylated epitopes. Treatment of histological sections with alkaline phosphatase prior to immunostaining resulted in reduction of axonal neurofilament staining with all three whilst the neurofibrillary tangles staining with BF10 was unaffected. Antibody 147 was found to recognise weakly some neurofibrillary tangles following alkaline phosphatase treatment. The results presented confirm the presence of structurally abnormal but phosphorylated neurofilaments in neurofibrillary tangles.

Alkaline Phosphatase↗