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 145 records · Page 8Linked to original sources

[Apolipoprotein B immunoreactivity in cerebral amyloid deposits and neurofibrillary tangles in senile dementia of Alzheimer type].

Since apolipoprotein E immunoreactivity has been shown in senile plaque and neurofibrillary tangle in Alzheimer's disease brains, we performed immunohistochemistry to examine whether or not apolipoprotein B (apoB) was associated with these abnormal structures. Sections of hippocampus from formalin-fixed, paraffin-embedded tissues were immunostained with a standard ABC method. We found that apoB immunoreactivity was associated with amyloid both in senile plaques and cerebral vessels and with neurofibrillary tangles. Positive staining was abolished with pretreatment of the antibody with the human apoB. It is suggested that the potential blood-brain barrier impairment may allow an increasing amount of serum proteins, such as apoB, to penetrate the brain and bind to these AD-associated abnormal structures.

Aged↗

Neurofibrillary tangles in elderly patients with late onset schizophrenia.

The objective of the present study was to examine whether neurofibrillary tangles densities are increased in elderly patients with late-onset schizophrenia (LOS). A neuropathological examination was performed in 32 consecutive autopsy brain specimens of ten patients with early-onset schizophrenia (EOS; onset of symptoms before the age of 40 years), eight patients with LOS (onset of symptoms after the age of 40 years) and 14 age-matched controls with no known neuropsychiatric disorder. Neurofibrillary tangle densities observed in the CA1 field of the hippocampus, the enthorhinal cortex, and the inferior temporal cortex in patients with LOS, EOS, and controls were not significantly different. All patients with EOS or LOS had Braak stages of III or less, which may correspond to normal aging. Thus, patients with schizophrenia, regardless of the age of onset of their symptoms, are no more prone to the development of Alzheimer's disease than the general population.

Age of Onset↗

Postencephalitic Parkinson's disease, amyotrophic lateral sclerosis on Guam and influenza revisited: focusing on neurofibrillary tangles and the trail of tau.

Circumstantial evidence links neuropathological changes in postencephalitic Parkinson's disease and amyotrophic lateral sclerosis on Guam to the 1918 influenza pandemic. Postencephalitic Parkinson's disease and amyotrophic lateral sclerosis have neuronal neurofibrillary tangles that anatomically correlate with clinical signs and symptoms. Occurrences of the disorders peaked in the early 1950s and are now disappearing. Neurovirulent influenza associated with the lethal 1918 pandemic is suggested as the etiology of both diseases. Permissive tissue antigens are considered an important contributing factor. Neurofibrillary tangles also correlate with signs and symptoms in Alzheimer's disease. Oxidative stress may be the pathological process that induces neurofibrillary tangles. Tangles contain abnormally phosphorylated tau. In Alzheimer's disease, tau is present in cerebrospinal fluid and is deposited in corpora amylacea, demonstrating the direction of cerebrospinal fluid flow.

Amyotrophic Lateral Sclerosis↗

Tryptamine induces tryptophanyl-tRNA synthetase-mediated neurodegeneration with neurofibrillary tangles in human cell and mouse models.

The neuropathological hallmarks of Alzheimer's disease (AD) and other taupathies include neurofibrillary tangles and plaques. Despite the fact that only 2-10% of AD cases are associated with genetic mutations, no nontransgenic or metabolic models have been generated to date. The findings of tryptophanyl-tRNA synthetase (TrpRS) in plaques of the AD brain were reported recently by the authors. Here it is shown that expression of cytoplasmic-TrpRS is inversely correlated with neurofibrillary degeneration, whereas a nonionic detergent-insoluble presumably aggregated TrpRS is simultaneously accumulated in human cells treated by tryptamine, a metabolic tryptophan analog that acts as a competitive inhibitor of TrpRS. TrpRSN- terminal peptide self-assembles in double-helical fibrils in vitro. Herein, tryptamine causes neuropathy characterized by motor and behavioral deficits, hippocampal neuronal loss, neurofibrillary tangles, amyloidosis, and glucose decrease in mice. Tryptamine induced the formation of helical fibrillary tangles in both hippocampal neurons and glia. Taken together with the authors' previous findings of tryptamine-induced nephrotoxicity and filamentous tangle formation in kidney cells, the authors' data indicates a general role of tryptamine in cell degeneration and loss. It is concluded that tryptamine as a component of a normal diet can induce neurodegeneration at the concentrations, which might be consumed along with food. Tryptophan-dependent tRNAtrp aminoacylation catalyzed by TrpRS can be inhibited by its substrate tryptophan at physiological concentrations was demonstrated. These findings indicate that the dietary supplementation with tryptophan as a tryptamine competitor may not counteract the deleterious influence of tryptamine. The pivotal role of TrpRS in protecting against neurodegeneration is suggested, providing an insight into the pathogenesis and a possible treatment of neurodegenerative diseases.

Animals↗

Microtubule-affinity regulating kinase (MARK) is tightly associated with neurofibrillary tangles in Alzheimer brain: a fluorescence resonance energy transfer study.

Paired helical filaments, the main structural components of the neurofibrillary tangles in Alzheimer disease, consist of phosphorylated tau protein. Because the levels and degree of phosphorylation are significantly higher in paired helical filament (PHF)-derived tau than in normal adult tau, and because phosphorylation of tau severely disrupts microtubule stability, it is postulated that tau phosphorylation is an important step in PHF formation. The kinases and/or phosphatases that act in vivo to help induce such a pathological state of tau, however, are not yet known. In this study we implicate the non-proline directed kinase MARK in PHF-tau phosphorylation, by virtue of its close intermolecular association with the phosphorylated Ser262 epitope on PHF-tau as assessed by fluorescence resonance energy transfer. Moreover, because this tight enzyme-substrate association is observed in neurofibrillary tangles in Alzheimer tissue, we suggest that PHF-tau phosphorylation may occur to some extent on assembled PHF filaments.

Alzheimer Disease↗

Presenile dementia with Lewy bodies and neurofibrillary tangles.

A 55-year-old man showed progressive mental deterioration over a five-year period along with a syndrome of "normal pressure hydrocephalus." At autopsy the main finding was the presence of two age-related neurocellular changes, the neurofibrillary tangle and the Lewy body, in limbic structures and in the pigmented nuclei of the brain stem. Cortical changes were mild, and senile plaques were not present. Electron microscopy occasionally showed an intimate relationship between the paired helical filaments of the neurofibrillary tangle and Lewy bodies in nerve cell processes in the hypothalamus. The findings suggest a closer relationship between Lewy bodies and neurofibrillary tangles than usually suspected. We also speculate that the presence of one type of age change in the brain may accelerate or predispose to other age changes.

Age Factors↗

Glial-neuronal interactions in Alzheimer disease: progressive association of IL-1alpha+ microglia and S100beta+ astrocytes with neurofibrillary tangle stages.

Activated microglia, overexpressing interleukin-1 (IL-1), and activated astrocytes, overexpressing S100beta, have been implicated in the formation and evolution of tau2-immunoreactive (tau2+) neuritic plaques in Alzheimer disease. In this study, we assessed the role of IL-1alpha+ microglia and S100beta+ astrocytes in the pathogenesis of another cardinal histopathological feature of Alzheimer disease: tau2+ neurofibrillary tangles. Four distinct stages of neurofibrillary tangle formation were identified: neurons with granular perikaryal tau2 immunoreactivity (stage 0); fibrillar neuronal inclusions (stage 1); dense, neuronal soma-filling inclusions (stage 2); and acellular, fibrillar deposits (stage 3, "ghost tangles"). The numbers of tangles in randomly selected fields of parahippocampal cortex from 11 Alzheimer patients correlated with both the numbers of IL-1alpha+ microglia and the numbers of S100beta+ astrocytes in these fields (r = 0.72, p < 0.02; r = 0.73, p = 0.01, respectively). There were progressive increases in frequency of association between tangle stages and both IL-1alpha+ microglia and S100beta+ astrocytes: 48, 56, 67, and 92% of stage 0-3 tangles, respectively, had associated IL-1alpha+ microglia; and 21, 37, 55, and 91% of stage 0-3 tangles had associated S100beta+ astrocytes. This progressive association of activated IL-1alpha+ microglia and activated S100beta+ astrocytes with tau2+ tangle stages suggests a role for glial-neuronal interactions in the degeneration of tangle-bearing neurons in Alzheimer disease.

Aged↗

A modified NOR-silver impregnation technique for amyloid plaques and neurofibrillary tangles: comparative assessment.

A modified nucleolar organizer region (NOR)-silver impregnation technique was recently introduced allowing the simultaneous staining of neurofibrillary tangles (NFT) and amyloid plaques (AP) in a single section. This impregnation technique proved to be very effective, rapid, of low cost, and to yield consistent results even in brain tissue fixed for long periods of time. In the present study, several silver impregnation and immunohistochemical techniques were applied and their reliability for the demonstration of NFT and AP was analysed. The modified NOR stain allowed the reliable and simultaneous demonstration of both amyloid plaques and neurofibrillary tangles; this method produced better results than the standard silver impregnation techniques. It is only in their early stages of formation that NFT cannot be detected by this method and, instead, immunohistochemistry for tau-2 is required. There was no significant difference in the staining properties for amyloid plaques between the modified NOR silver impregnation technique and the anti-beta-A4 immunostain.

Aged↗

The apolipoprotein E allele epsilon 4 does not correlate with the number of senile plaques or neurofibrillary tangles in patients with Alzheimer's disease.

BACKGROUND AND OBJECTIVES: Apolipoprotein E (apoE) has been implicated in regenerative processes in the brain after trauma, as well as in the pathogenesis of Alzheimer's disease. Inheritance of a specific apo epsilon allele (apo epsilon 4) determines in part the risk and the mean age at onset of Alzheimer's disease. ApoE has been found to bind isoform specifically to beta-amyloid protein, the major component of senile plaques, and to the microtubule associated protein tau, which forms paired helical filaments and neurofibrillary tangles. The aim was to further examine the relation between apo epsilon alleles, especially apo epsilon 4, and the development of neuropathological changes associated with Alzheimer's disease. METHODS: Brains of patients with Alzheimer's disease (n = 44) and vascular dementia (n = 11) and of age matched controls (n = 29) were studied. Senile plaques and neurofibrillary tangles in the hippocampus and frontal cortex were quantified. RESULTS: No correlation was found between the number of apo epsilon 4 alleles and the number of senile plaques and neurofibrillary tangles in the hippocampus or the frontal cortex of patients with Alzheimer's disease, or vascular dementia, or control groups. No significant differences in duration or severity of dementia were found between patients with or. without the apo epsilon 4 allele. No increased frequency of apo epsilon 4 was found in vascular dementia. CONCLUSION AND COMMENT: Although the apo epsilon genotype clearly affects whether Alzheimer's disease will develop or not, the present study suggests that it has no influence on pathology or clinical intellectual status, once the dementia has manifested itself. No increased apo epsilon 4 allele frequency was found in neuropathologically diagnosed patients with vascular dementia in whom concomitant Alzheimer's disease can be excluded.

Aged↗

The neuropathology of Williams syndrome. Report of a 35-year-old man with presenile beta/A4 amyloid plaques and neurofibrillary tangles.

OBJECTIVE: To study neuropathologically Williams syndrome in a 35-year-old patient. METHODS: Sections from multiple regions of the brain were examined with luxol fast blue and hematoxylineosin staining, and selected sections were stained with the silver impregnation technique (Bielschowsky technique) and Congo red. In addition, immunohistochemistry with monoclonal antibodies against glial fibrillary acidic protein, beta/A4 amyloid, paired helical filaments, and phosphorylated tau protein was performed on cortical, hippocampal, amygdaloid, and basal ganglian sections. RESULTS: No specific macroscopic or microscopic abnormalities were recognized that are specific for Williams syndrome. The histopathologic examination did, however, demonstrate the presence of Alzheimer-type changes, including beta/A4 amyloid-containing senile plaques and scattered neurofibrillary tangles in neocortex and medial temporal lobe structures (entorhinal cortex, CA1 area of the hippocampus, and amygdala). Plaques were most numerous in the amygdala (7/mm2) and in the entorhinal cortex (4/mm2). Neurofibrillary tangles were less numerous (< 1/mm2), except in the hippocampus, where approximately 2/mm2 were found. CONCLUSIONS: To our knowledge, ours represents the first neuropathologic description of a patient with Williams syndrome. Although Williams syndrome is usually sporadic, familial cases have been reported along with candidate chromosomal loci. If our findings are confirmed in additional patients with Williams syndrome, they may provide clues to other factors that are important in the pathogenesis of senile plaques (with beta/A4 amyloid deposition) and neurofibrillary tangles.

Adult↗

Rattan bamboo blind (Japanese sudare)-like profiles of neurofibrillary tangles in Alzheimer's disease.

An unusual ultrastructure for neurofibrillary tangles, which has not been described so far, is presented in a case of Alzheimer's disease. This profile consists of parallelly arranged paired helical filaments and criss-cross tubular profiles that are arranged at regular interval of 300-500 nm, resembling rattan bamboo blind or Japanese sudare-like profiles. Coexistence of Hirano bodies in the same neuron is infrequently encountered.

Alzheimer Disease↗

Caspase cleavage of tau: linking amyloid and neurofibrillary tangles in Alzheimer's disease.

The principal pathological features of Alzheimer's disease (AD) are extracellular amyloid plaques and intracellular neurofibrillary tangles, the latter composed of the microtubule-binding protein tau assembled into paired helical and straight filaments. Recent studies suggest that these pathological entities may be functionally linked, although the mechanisms by which amyloid deposition promotes pathological tau filament assembly are poorly understood. Here, we report that tau is proteolyzed by multiple caspases at a highly conserved aspartate residue (Asp421) in its C terminus in vitro and in neurons treated with amyloid-beta (Abeta) (1-42) peptide. Tau is rapidly cleaved at Asp421 in Abeta-treated neurons (within 2 h), and its proteolysis appears to precede the nuclear events of apoptosis. We also demonstrate that caspase cleavage of tau generates a truncated protein that lacks its C-terminal 20 amino acids and assembles more rapidly and more extensively into tau filaments in vitro than wild-type tau. Using a monoclonal antibody that specifically recognizes tau truncated at Asp421, we show that tau is proteolytically cleaved at this site in the fibrillar pathologies of AD brain. Taken together, our results suggest a novel mechanism linking amyloid deposition and neurofibrillary tangles in AD: Abeta peptides promote pathological tau filament assembly in neurons by triggering caspase cleavage of tau and generating a proteolytic product with enhanced polymerization kinetics.

Alzheimer Disease↗

Evidence for the association of protein 4.1 immunoreactive forms with neurofibrillary tangles in Alzheimer's disease brains.

The formation of neurofibrillary tangles (NFTs) and paired-helical filaments (PHFs) in Alzheimer's disease (AD) reflects a major disorganization of the cytoskeleton. The role of the neuronal membrane skeleton in the development of these abnormalities has not previously been investigated. In this study, we used 9 antibodies raised against the erythrocyte membrane skeleton protein 4.1 (P4.1) for immunocytochemical and immunoblot analyses to investigate whether or not the brain homologues of this protein were constituents of NFTs or PHFs. Our results show that 7 of the 9 monospecific antibodies against the human and pig erythrocyte P4.1 stained NFTs in the prefrontal cortex and hippocampus of AD brains. The P4.1 antibodies used here did not cross-react with tau protein isolated from AD brain, and preabsorption of these antibodies with tau protein did not cause loss of NFT staining. In age-matched control brains, these P4.1 antibodies stained neuronal cell bodies or nuclei. Six of the antibodies also stained isolated NFTs but the SDS-insoluble NFTs were immunostained only by two of the P4.1 antibodies. By using inositol hexaphosphate affinity chromatography and immunoblot analysis, we identified a 68-kDa protein as the most likely brain analogue of P4.1. When SDS-extracted proteins from the isolated NFTs were immunoblotted, a 50-kDa band was immunostained. The 68-kDa and 50-kDa proteins were not stained by tau protein and neurofilament subunit NF-H antibodies, that strongly stained NFTs. We conclude that brain protein 4.1 isoform(s) are constituents of NFTs in AD.

Aged↗

Selective accumulation of aluminum and iron in the neurofibrillary tangles of Alzheimer's disease: a laser microprobe (LAMMA) study.

We report the results of an examination of the elemental content of neurofibrillary tangle-bearing and neurofibrillary tangle-free neurons identified within the hippocampus of 10 subjects with Alzheimer's disease and 4 neuropathologically intact age-matched control subjects. The study employed laser microprobe mass analysis (LAMMA), a technique that provides extremely sensitive multielement detection in plastic-embedded, semithin-sectioned tissues. Evidence for the selective accumulation of aluminum within the neurofibrillary tangle-bearing neurons was obtained in all 10 subjects with Alzheimer's disease. The site of aluminum deposition within these cells was the neurofibrillary tangle itself, and not the "nuclear region," as we previously reported. Iron accumulation was also detected within neurofibrillary tangles. Evaluation for the accumulation of other elements within the tangle-bearing neurons failed to reveal any other metallic element as being consistently present. In addition, probe sites directed to neurons identified in snap-frozen cryostat sections from 2 subjects with Alzheimer's disease revealed similar spectra with prominent aluminum-related peaks, confirming that our findings are not related to exogenous contamination through fixation, embedding, or other procedures prior to analysis. This study further confirms the association of aluminum and neurofibrillary tangle formation in Alzheimer's disease.

Aluminum↗

Alzheimer's disease: immunoreactivity of neurofibrillary tangles with anti-neurofilament and anti-paired helical filament antibodies.

The origin of the paired helical filaments (PHF) that accumulate in human neurons during aging and in Alzheimer's disease and their relationship to normal neurofilaments remain unclear. The observation that a rabbit antiserum to highly enriched PHF fractions specifically labeled PHF in Alzheimer neurofibrillary tangles but showed no reaction with neurofilaments or other normal cytoskeletal proteins led us to compare this antiserum to two monoclonal antibodies, RT97 and BF10, previously found to cross-react with tangles and with the 210,000 and 155,000 mol. wt. neurofilament proteins, respectively. Both alpha-PHF serum and the neurofilament monoclonals strongly immunolabel almost all neurofibrillary tangles in Alzheimer cortical sections. Double-immunolabeling studies show that both reagents recognize the same tangles and usually show identical patterns of staining of intraneuronal fibrous material. Following prolonged extraction of cortex in sodium dodecyl sulfate, a step which removes normal neurofilaments but leaves PHF intact, almost all isolated tangles retain strong immunoreactivity with alpha-PHF serum at an intensity which is slightly reduced from that in cortical sections. In contrast, only a small number of isolated tangles are stained strongly by RT97 and BF10; most show much decreased or no reactivity with these monoclonal neurofilament antibodies. This differential immunoreactivity was confirmed by double-labeling studies. Tangles prepared under gentle extraction conditions show strong reactivity with alpha-PHF antibodies but again only a small number are strongly labeled by RT97 and BF10. We conclude that neurofibrillary tangles in Alzheimer's disease are heterogeneous as regards their filamentous content and contain both antigens cross-reacting with neurofilaments and antigens which are apparently unique to PHF and not shared with normal neurofilaments.

Alzheimer Disease↗

Tau and ubiquitin immunoreactivity at different stages of formation of Alzheimer neurofibrillary tangles.

In his original 1911 publication Alois Alzheimer classified neurofibrillary tangles (ANT) into three morphologically defined subgroups according to their stage of maturation. The present study shows that changes in the morphological appearance of ANT during their maturation process are accompanied by changes in their antigenic profile. As shown by several immunocytochemical studies these abnormal phosphorylated microtubule-associated protein tau and of ubiquitin. In this study, immunoreactivity for the altered tau is not only seen in a subset of tangles but also in the cytoplasm of some nerve cells lacking ANT, which we believe to be at a stage of neuronal alteration preceding the formation of compact tangles (Stage 0 tangles). Similar numbers of Stage 0 tangles are present in the brains of age-matched non-demented individuals as in Alzheimer cases, but are absent in young controls lacking ANT. In extracellular "ghost tangles", the ultimate stage of neurofibrillary degeneration, immunoreactivity for tau is accessible to antibodies only when tissue sections are pretreated with formic acid to uncover the binding sites. In contrast to tau, presence/accessibility of an epitope residing on residues 50-65 of ubiquitin recognized by a monoclonal antibody raised to paired helical filaments (3-39) increases during the maturation of ANT and is most pronounced in "ghost tangles". Appearance/uncovering of the 3-39 epitope and masking of tau reactivity during tangle maturation may reflect degradation or conformational changes in the pathological filaments due to their aging and the final loss of their parent nerve cells.

Aged↗

Frequency of Alzheimer's neurofibrillary tangles in the cerebral cortex in progressive supranuclear palsy (subcortical argyrophilic dystrophy).

The frequency of Alzheimer's neurofibrillary tangles was studied, employing large sections of the cerebral hemispheres, in the cerebral cortex in 2 cases of progressive supranuclear palsy. The majority of the neurofibrillary tangles were found in the smaller nerve cells of the third layer. The typical triangular form was rare, and most of them showed argyrophilic neurofibrillary filaments which coiled around the well-preserved nucleus. We concluded that their occurrence in the cerebral cortex is one of the morphological manifestations of the disease process.

Aged↗

Neurofibrillary tangles in Niemann-Pick disease type C.

Post-mortem neuropathological examination of five cases of Niemann-Pick disease type C revealed neurofibrillary tangles in many parts of the brain. Tangles were a consistent finding in the hippocampus, hypothalamus, substantia innominata, midbrain pons and medulla. Other regions of the brain in which tangles were present included neocortex, basal ganglia, thalamus, cerebellar cortex in one case, and dentate nucleus in another. The tangles were argyrophilic, fluoresced under ultraviolet light when stained with thioflavin S, and reacted strongly with antibody to tau protein. Some of the tangles could be immunostained for ubiquitin. Electron microscopy, performed in one of the cases, showed the tangles to consist of paired helical filaments ultrastructurally identical to those of Alzheimer's disease. The distribution of the tangles in the central nervous system as a whole and also within many individual neurons corresponded fairly closely with that of the abnormal storage material. Both the tangles and the storage material extended into, and distended, the proximal parts of many dendrites and axons. No A4/beta protein, either in the form of plaques or in the walls of blood vessels, was detected in any of the cases. Our findings suggest that neurofibrillary tangles are a common feature of Niemann-Pick disease type C and that their formation may be a reaction to the abnormal storage material.

Adolescent↗