path(MESH:"Plaque, Amyloid")
The histopathological changes in the brain include the presence of extracellular amyloid plaques consisted of various peptide variants of amyloid β (Aβ) and accumulation of intracellular neurofibrillary tangles (NFTs) composed mainly of phosphorylated Tau proteins (pTau), localized predominantly in neurons (reviewed by Serrano-Pozo et al. 2011). PubMed:29196815
Extracellular neuritic plaques are deposits of differently sized small peptides called beta-amyloid (Abeta) that are derived via sequential proteolytic cleavages of the b-amyloid precursor protein (APP) [6] PubMed:21214928
In Down Syndrome (DS) patients, the accumulation of intracellular Abeta precedes extracellular plaque formation [148] and the level of intraneuronal Ab decreases as the extracellular Abeta plaques accumulate [149] PubMed:21214928
However, a recent study blocking the conversion of testosterone to estrogen found an estrogen-independent improvement in cognitive function and lowering of plaque formation along with a decrease in BACE1 mRNA, protein level, and activity [211]. In addition, testosterone may also reduce the protein level of PS1 [196] PubMed:21214928
There are reports showing that the protein and mRNA levels of KPI-containing APP isoforms are elevated in AD brain and associated with increased Ab deposition [9]; and prolonged activation of extrasynaptic NMDA receptor in neurons can shift APP expression from APP695 to KPI-containing APP isoforms, accompanied with increased production of Ab [10] PubMed:21214928
There are reports showing that the protein and mRNA levels of KPI-containing APP isoforms are elevated in AD brain and associated with increased Ab deposition [9]; and prolonged activation of extrasynaptic NMDA receptor in neurons can shift APP expression from APP695 to KPI-containing APP isoforms, accompanied with increased production of Ab [10] PubMed:21214928
Studies done on familial AD (FAD) mutations consistently show increases in the ratio of Abeta42/40 [105,144], suggesting that elevated levels of Abeta42 relative to Abeta40 is critical for AD pathogenesis, probably by providing the core for Abeta assembly into oligomers, fibrils and amyloidogenic plaques [145,146] PubMed:21214928
gamma-Secretase further cleaves C99 to release AICD and the amyloidogenic Abeta peptide which aggregates and fibrillates to form amyloid plaques in the brain PubMed:22122372
gamma-Secretase further cleaves C99 to release AICD and the amyloidogenic Abeta peptide which aggregates and fibrillates to form amyloid plaques in the brain PubMed:22122372
Moderate neuronal over-expression of human ADAM10 increases sAPP-alpha production while reducing Abeta generation/ plaque formation in mice carrying the human APP V717I mutation, while expression of a catalytically-inactive form of the ADAM10 mutation increases the size and number of amyloid plaques in mouse brains (Postina et al. 2004) PubMed:22122372
Among the various Ab peptides generated by the multiplesite cleavages of secretases, Abeta 42 has proved to be more hydrophobic and amyloidogenic than others (Burdick et al. 1992) PubMed:22122372
Studies also suggest that increased Abeta 42 levels probably provide the core for oligomerization, fibrillation and amyloid plaque generation (Jarrett et al. 1993; Iwatsubo et al. 1994) PubMed:22122372
AD is the most common form of dementia in the elderly population. The histopathology of this disease is well known to have at least four components: 1) loss of cholinergic neurotransmission, 2) deposition of extracellular Abeta peptides into plaques, 3) hyperphosphorylation of the tau protein that leads to excessive formation of neurofibrillar tangles, and 4) increased local inflammation. PubMed:19126755
The loss of nAChR subunits, as determined by [3H]- epibatidine binding, seems to take place after the transition from mild cognitive impairment (MCI) to AD (Sabbagh et al., 2006), although the loss of epibatidine binding did not correlate with decline in memory, cognitive performance, or with the development of neurofibrillary tangles or plaques (Sabbagh et al., 2001). PubMed:19293145
In addition, not only have alpha7 nAChRs been found colocalized with plaques (Wang et al., 2000b) but alpha7 and alpha4 subunits are also positively correlated with neurons that accumulate Abeta (Wevers et al., 1999). PubMed:19293145
AD is characterized pathologically by the occurrence of intracellular neurofibrillary tangles rich in tau protein and extracellular plaques containing amyloid peptides (Price et al., 1991). PubMed:19293145
APP and APP/presenilin-1 (PS-1) mice do not show neurodegeneration (Irizarry et al., 1997) and yet show several features of AD, including accumulation of plaques and defects in learning (Hsiao et al., 1996), suggesting that many features of AD are not the result of neuronal loss. These animals nonetheless have swollen cholinergic nerve terminals at 12 months, suggesting defective nerve sprouting (Hernandez et al., 2001). PubMed:19293145
The hallmarks of AD pathology are the accumulation of amyloid-beta (Abeta) peptide aggregates (neuritic plaques) and hyperphosphorylated tau protein (neurofibrillary tangles). PubMed:24511233
Senile plaques consist of deposits of small peptides called beta-amyloid (Abeta). Multiple lines of evidence suggest that the overproduction/ aggregation of neurotoxic Abeta in vulnerable brain regions is the primary cause of AD PubMed:24590577
Chronic treatment with AF267B reduces Abeta plaques and tau hyperphosphorylation and rescues learning and memory impairments in 3×Tg AD mice PubMed:24590577
Recent evidence indicates that cholinergic hypofunction is closely linked to Abeta and tau pathologies[20]. As a major receptor group for ACh, mAChRs have also been implicated in the pathophysiology of AD. PubMed:24590577
though there are contradictory findings showing that the alpha-secretase-mediated APP processing via M1 mAChR stimulation is not modulated by the ERK1/MEK cascade[71]. On the other hand, loss of M1 mAChR increases amyloidogenic APP processing in neurons and promotes brain Abeta plaque pathology in a mouse model of AD PubMed:24590577
Alzheimer’s disease (AD) is a debilitating neurodegenerative disorder afflicting millions of people. It is diagnosed by the progressive loss of cognitive function and behavioral defi cits and is characterized by the presence of neurofibrillary tangles (NFTs), senile plaques, cholinergic neuron loss, and neuronal atrophy at autopsy PubMed:24590577
In a mouse model of AD, cotinine treatment decreased the plaque load and was able to activate the Akt pathway, that was shown to be neuroprotective (Echeverria et al., 2011) PubMed:25514383
Even though nicotine showed a positive effect reducing plaque load (Hellstrom-Lindahl et al., 2004; Inestrosa et al., 2013; Nordberg et al., 2002), its use in AD treatment should be limited due to its toxic effect on tau pathology PubMed:25514383
As a consequence of the lower Abeta concentration, the plaque load was clearly reduced in APP-alpha7KO mice PubMed:25514383
They showed that alpha7 subunits co-localize with Abeta1-42 in senile plaques of brain slices obtained from patients that suffered from sporadic AD PubMed:25514383
Dementia is a debilitating condition frequent in ageing populations, and Alzheimer's Disease (AD) accounts for 70% of all dementia cases. AD is characterized by neuropathological hallmarks consisting of an accumulation of Amyloid beta peptide (Ab) in extracellular plaques, intracellular deposits of tau protein, neuronal loss and, more recently, a prominent synaptic loss was identified (Braak and Braak,1991; Masliah et al., 2001; Selkoe,1991; Spires-Jones and Hyman, 2014) PubMed:25514383
Several studies showed that in AD animal models, the appearance of the cognitive deficits precedes plaque deposition (Casas et al., 2004; Gouras et al., 2000; Kumar et al., 2013; Wirths et al., 2004) PubMed:27522251
This mutation at codon 670/671 on the APP gene on chromosome 21 was discovered in a Swedish family, and the mutation is unique in the sense that it is the only AD mutation that has been shown to alter the APP metabolism, resulting in an overexpression of the amyloid leading to plaque formation (Mullan et al 1992) PubMed:11230871
Amyloid plaques form in the entorhinal cortex of patients with Alzheimer’s disease and this region, which connects the neocortex and the hippocampus, plays a crucial part in memory. it has been suggested that plaques in this region represent the lytic remnants of degenerated, Abeta1–42-burdened pyramidal neurons, and that amyloid internalization depends on alpha7 nAChR mediated Ca2+ entry162. Of interest, chronic nicotine treatment has been shown to reduce the plaque burden in animal models of Alzheimer’s disease123. PubMed:19721446
Amyloid plaques form in the entorhinal cortex of patients with Alzheimer’s disease and this region, which connects the neocortex and the hippocampus, plays a crucial part in memory. it has been suggested that plaques in this region represent the lytic remnants of degenerated, Abeta1–42-burdened pyramidal neurons, and that amyloid internalization depends on alpha7 nAChR mediated Ca2+ entry162. Of interest, chronic nicotine treatment has been shown to reduce the plaque burden in animal models of Alzheimer’s disease123. PubMed:19721446
The plaques in AD are rich in amyloid beta peptides (Abeta) that are produced by proteolytic cleavage of the amyloid precursor peptide (APP), a glycolipid located in the outer cell membrane PubMed:14556719
Patients with AD display two types of protein deposits: extracellular amyloid plaques and intracellular neurofibrillary tangles (Hardy and Selkoe, 2002). PubMed:14556719
In these transgenic mice LC3-positive bodies were particularly apparent in neurites surrounding amyloid plaques, and immunoblotting of hippocampi from 6 month old transgenic PS1/APP mice revealed increased levels of LC3-II compared to wild-type mice (81) PubMed:24027553
AD brain samples contain exosomal proteins within amyloid plaques hinting that exosomes play part in disease pathology (Rajendran et al., 2006) PubMed:28420982
AD (Alzheimer’s disease) is a progressive neurodegenerative disorder characterized by the extracellular accumulation of senile plaques composed of Aβ (amyloid β-peptide) and the intracellular accumulation of the MAP (microtubuleassociated protein) tau into both non-filamentous and filamentous inclusions, such as NFTs (neurofibrillary tangles), NTs (neuropil threads) and NPs (neuritic plaques) [1,2] PubMed:22817713
Xiao et al. have also obtained the consistent conclusion that transcriptional factor EB, a master regulator of lysosome biogenesis, improves lysosomal function in astrocytes, which may promote Aβ clearance and attenuate plaque pathogenesis (Xiao et al. 2014) PubMed:29626319
ATRA prevents the accumulation of amyloid plaques and APP processing into Ab through downregulation of Cdk5 in APP/PS1 mice. These results suggested that the administration of ATRA inhibited activity of Cdk5 and GSK3b and attenuated the formation of p-tau aggregation, including p-CRMP2 and p-WAVE1 in the 33Tg mouse brain. PubMed:26400044
We were prompted to carry out this study because Acr is mainly localized in the neurons [54], is found in association with NFTs and dystrophic neurites surrounding senile plaques [55], is highly toxic to neurons, is found elevated 2–5 fold in affected regions of AD brain. EC can sequester highly reactive and toxic byproducts of oxidation such as acrolein. PubMed:23531502
We found that the immunoreactivities of p-WAVE1 and pCRMP2 colocalized with p-tau and were located near peripheral amyloid plaques in the cerebral cortices of 23- month-old 33Tg (Fig. 3A) and 17-month-old APPswe/ PS1DE9 (Fig. 3B) mice. PubMed:26400044
The pSer422 antibody displayed an almost identical pattern to that of AT8, in that it stained NFTs (Figure 5A–D), neuropil threads and neuritic plaques (Figure 5E–H) PubMed:18239272
We show here that ITPKB protein level was increased 3-fold in the cerebral cortex of most patients with Alzheimer's disease compared with control subjects, and accumulated in dystrophic neurites associated to amyloid plaques. In mouse Neuro-2a neuroblastoma cells, Itpkb overexpression was associated with increased cell apoptosis and increased β-secretase 1 activity leading to overproduction of amyloid-β peptides. In this cellular model, an inhibitor of mitogen-activated kinase kinases 1/2 completely prevented overproduction of amyloid-β peptides. Transgenic overexpression of ITPKB in mouse forebrain neurons was not sufficient to induce amyloid plaque formation or tau hyperphosphorylation. However, in the 5X familial Alzheimer's disease mouse model, neuronal ITPKB overexpression significantly increased extracellular signal-regulated kinases 1/2 activation and β-secretase 1 activity, resulting in exacerbated Alzheimer's disease pathology as shown by increased astrogliosis, amyloid-β40 peptide production and tau hyperphosphorylation. PubMed:24401760
This antibody detects nitrated tau in soluble preparations from both severe AD brains (Braak stage V, VI) and age-matched controls, suggesting that nitration at Tyr 18 may be linked to astrocyte activation, an early event associated with amyloid plaque formation PubMed:18562203
We found an increase in Syk activation in DNs surrounding Aβ deposits as well as in neurons displaying an accumulation of phosphorylated Tau at Y18 and elevated levels of MC1 pathogenic tau conformers in AD brain sections whereas only weak immunoreactivity for pSyk was observed in brain sections from a non-demented control PubMed:28877763
The upregulation of Syk activation observed in the brains of Tg APPsw and Tg PS1/APPsw is mainly attributable to pSyk accumulations in dystrophic neurites that are associated with Aβ plaques and increase with age and Aβ burden. PubMed:28877763
Similarly, inhibiting the NLRP3 inflammasome reduces the neuritic plaque burden in an AD transgenic mouse model (Shi et al., 2013) PubMed:24561250
Compromised macroautophagy, via the genetic suppression of Atg7, leads to the blockade of Aβ secretion and contributes to the subsequent diminution in extracellular Aβ plaque load PubMed:29758300
Overexpression of PICALM in APP/PS1 mice substantially elevates Aβ levels, whereas knockdown reduces the Aβ plaque load, respectively [98] PubMed:29758300
Formation of amyloid β (Aβ) plaques is one of the most notable hallmarks in AD pathology [30] PubMed:29758300
In transgenic mouse models of AD, synaptic deficits have been detected prior to the formation of amyloid plaques (Hsia et al. 1999). PubMed:22908190
It has been reported that downregulation of BACE1‐AS reduces the amount of β‐ameloid and plaques PubMed:30663117
Increased presence of activated glial cells presenting elevated NF-κB and HLA-DR expression are commonly observed around the Aβ plaques in postmortem AD tissue PubMed:25652642
A consequence of intracellular and parenchymal accumulation of NPs and NFTs is activation of NF-κB in the neural and glial cells with subsequent protective or detrimental effects PubMed:25652642
Increased presence of activated glial cells presenting elevated NF-κB and HLA-DR expression are commonly observed around the Aβ plaques in postmortem AD tissue PubMed:25652642
The histopathological changes in the brain include the presence of extracellular amyloid plaques consisted of various peptide variants of amyloid β (Aβ) and accumulation of intracellular neurofibrillary tangles (NFTs) composed mainly of phosphorylated Tau proteins (pTau), localized predominantly in neurons (reviewed by Serrano-Pozo et al. 2011). PubMed:29196815
AD is the most common form of dementia in the elderly population. The histopathology of this disease is well known to have at least four components: 1) loss of cholinergic neurotransmission, 2) deposition of extracellular Abeta peptides into plaques, 3) hyperphosphorylation of the tau protein that leads to excessive formation of neurofibrillar tangles, and 4) increased local inflammation. PubMed:19126755
AD is characterized pathologically by the occurrence of intracellular neurofibrillary tangles rich in tau protein and extracellular plaques containing amyloid peptides (Price et al., 1991). PubMed:19293145
The accumulation of plaques consisting of Abeta is one of the histopathological hallmarks of AD. Abeta is the product of serial cleavage of the amyloid precursor protein (APP) first by beta and then by gamma secretases to yield Abeta peptides of varying lengths, predominantly the 37-, 40-, and 42- residue forms. PubMed:19293145
APP and APP/presenilin-1 (PS-1) mice do not show neurodegeneration (Irizarry et al., 1997) and yet show several features of AD, including accumulation of plaques and defects in learning (Hsiao et al., 1996), suggesting that many features of AD are not the result of neuronal loss. These animals nonetheless have swollen cholinergic nerve terminals at 12 months, suggesting defective nerve sprouting (Hernandez et al., 2001). PubMed:19293145
In addition, not only have alpha7 nAChRs been found colocalized with plaques (Wang et al., 2000b) but alpha7 and alpha4 subunits are also positively correlated with neurons that accumulate Abeta (Wevers et al., 1999). PubMed:19293145
Intracerebral injection of Abeta into rats resulted in a loss of alpha4 and alpha7 subunits as measured by Western blotting but an increase in alpha7 mRNA (Liu et al., 2008), again suggesting that Abeta directly reduces expression of alpha7 nAChRs through mechanisms other than reduced mRNAproduction, although caution should be exercised in interpreting quantitative data from Western blot studies. It is noteworthy that a combined patch-clamp and in situ hybridization study of dissociated human brain tissue (obtained as route-of-access tissue removed during surgery) indicated that neurons near Abeta plaques retained alpha4 and alpha7 mRNA transcripts, whereas these transcripts were absent in neurons burdened with hyperphosphorylated tau protein (Wevers et al., 1999). PubMed:19293145
Intracerebral injection of Abeta into rats resulted in a loss of alpha4 and alpha7 subunits as measured by Western blotting but an increase in alpha7 mRNA (Liu et al., 2008), again suggesting that Abeta directly reduces expression of alpha7 nAChRs through mechanisms other than reduced mRNAproduction, although caution should be exercised in interpreting quantitative data from Western blot studies. It is noteworthy that a combined patch-clamp and in situ hybridization study of dissociated human brain tissue (obtained as route-of-access tissue removed during surgery) indicated that neurons near Abeta plaques retained alpha4 and alpha7 mRNA transcripts, whereas these transcripts were absent in neurons burdened with hyperphosphorylated tau protein (Wevers et al., 1999). PubMed:19293145
The hallmarks of AD pathology are the accumulation of amyloid-beta (Abeta) peptide aggregates (neuritic plaques) and hyperphosphorylated tau protein (neurofibrillary tangles). PubMed:24511233
The hallmarks of AD pathology are the accumulation of amyloid-beta (Abeta) peptide aggregates (neuritic plaques) and hyperphosphorylated tau protein (neurofibrillary tangles). PubMed:24511233
The popular amyloid cascade hypothesis posits that the gradual build-up of Abeta plaques leads to neuronal inflammation, dysfunction, and, eventually, cell death. The two brain regions most critically affected by this degeneration are the cortex and hippocampus, both of which are involved in cognition, learning, and memory. PubMed:24511233
The popular amyloid cascade hypothesis posits that the gradual build-up of Abeta plaques leads to neuronal inflammation, dysfunction, and, eventually, cell death. The two brain regions most critically affected by this degeneration are the cortex and hippocampus, both of which are involved in cognition, learning, and memory. PubMed:24511233
Alzheimer’s disease (AD) is a debilitating neurodegenerative disorder afflicting millions of people. It is diagnosed by the progressive loss of cognitive function and behavioral defi cits and is characterized by the presence of neurofibrillary tangles (NFTs), senile plaques, cholinergic neuron loss, and neuronal atrophy at autopsy PubMed:24590577
Recent evidence indicates that cholinergic hypofunction is closely linked to Abeta and tau pathologies[20]. As a major receptor group for ACh, mAChRs have also been implicated in the pathophysiology of AD. PubMed:24590577
Dementia is a debilitating condition frequent in ageing populations, and Alzheimer's Disease (AD) accounts for 70% of all dementia cases. AD is characterized by neuropathological hallmarks consisting of an accumulation of Amyloid beta peptide (Ab) in extracellular plaques, intracellular deposits of tau protein, neuronal loss and, more recently, a prominent synaptic loss was identified (Braak and Braak,1991; Masliah et al., 2001; Selkoe,1991; Spires-Jones and Hyman, 2014) PubMed:25514383
They showed that alpha7 subunits co-localize with Abeta1-42 in senile plaques of brain slices obtained from patients that suffered from sporadic AD PubMed:25514383
The plaques in AD are rich in amyloid beta peptides (Abeta) that are produced by proteolytic cleavage of the amyloid precursor peptide (APP), a glycolipid located in the outer cell membrane PubMed:14556719
In these transgenic mice LC3-positive bodies were particularly apparent in neurites surrounding amyloid plaques, and immunoblotting of hippocampi from 6 month old transgenic PS1/APP mice revealed increased levels of LC3-II compared to wild-type mice (81) PubMed:24027553
AD brain samples contain exosomal proteins within amyloid plaques hinting that exosomes play part in disease pathology (Rajendran et al., 2006) PubMed:28420982
AD (Alzheimer’s disease) is a progressive neurodegenerative disorder characterized by the extracellular accumulation of senile plaques composed of Aβ (amyloid β-peptide) and the intracellular accumulation of the MAP (microtubuleassociated protein) tau into both non-filamentous and filamentous inclusions, such as NFTs (neurofibrillary tangles), NTs (neuropil threads) and NPs (neuritic plaques) [1,2] PubMed:22817713
We were prompted to carry out this study because Acr is mainly localized in the neurons [54], is found in association with NFTs and dystrophic neurites surrounding senile plaques [55], is highly toxic to neurons, is found elevated 2–5 fold in affected regions of AD brain. EC can sequester highly reactive and toxic byproducts of oxidation such as acrolein. PubMed:23531502
This antibody detects nitrated tau in soluble preparations from both severe AD brains (Braak stage V, VI) and age-matched controls, suggesting that nitration at Tyr 18 may be linked to astrocyte activation, an early event associated with amyloid plaque formation PubMed:18562203
We found that the immunoreactivities of p-WAVE1 and pCRMP2 colocalized with p-tau and were located near peripheral amyloid plaques in the cerebral cortices of 23- month-old 33Tg (Fig. 3A) and 17-month-old APPswe/ PS1DE9 (Fig. 3B) mice. PubMed:26400044
The pSer422 antibody displayed an almost identical pattern to that of AT8, in that it stained NFTs (Figure 5A–D), neuropil threads and neuritic plaques (Figure 5E–H) PubMed:18239272
The upregulation of Syk activation observed in the brains of Tg APPsw and Tg PS1/APPsw is mainly attributable to pSyk accumulations in dystrophic neurites that are associated with Aβ plaques and increase with age and Aβ burden. PubMed:28877763
We found an increase in Syk activation in DNs surrounding Aβ deposits as well as in neurons displaying an accumulation of phosphorylated Tau at Y18 and elevated levels of MC1 pathogenic tau conformers in AD brain sections whereas only weak immunoreactivity for pSyk was observed in brain sections from a non-demented control PubMed:28877763
We show here that ITPKB protein level was increased 3-fold in the cerebral cortex of most patients with Alzheimer's disease compared with control subjects, and accumulated in dystrophic neurites associated to amyloid plaques. In mouse Neuro-2a neuroblastoma cells, Itpkb overexpression was associated with increased cell apoptosis and increased β-secretase 1 activity leading to overproduction of amyloid-β peptides. In this cellular model, an inhibitor of mitogen-activated kinase kinases 1/2 completely prevented overproduction of amyloid-β peptides. Transgenic overexpression of ITPKB in mouse forebrain neurons was not sufficient to induce amyloid plaque formation or tau hyperphosphorylation. However, in the 5X familial Alzheimer's disease mouse model, neuronal ITPKB overexpression significantly increased extracellular signal-regulated kinases 1/2 activation and β-secretase 1 activity, resulting in exacerbated Alzheimer's disease pathology as shown by increased astrogliosis, amyloid-β40 peptide production and tau hyperphosphorylation. PubMed:24401760
Formation of amyloid β (Aβ) plaques is one of the most notable hallmarks in AD pathology [30] PubMed:29758300
A consequence of intracellular and parenchymal accumulation of NPs and NFTs is activation of NF-κB in the neural and glial cells with subsequent protective or detrimental effects PubMed:25652642
Increased presence of activated glial cells presenting elevated NF-κB and HLA-DR expression are commonly observed around the Aβ plaques in postmortem AD tissue PubMed:25652642
Increased presence of activated glial cells presenting elevated NF-κB and HLA-DR expression are commonly observed around the Aβ plaques in postmortem AD tissue PubMed:25652642
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