CoChat
Sign Up
Cited by 89Alzheimer's disease research and treatmentsNeuroinflammation and Neurodegeneration MechanismsDementia and Cognitive Impairment Research

Blocking the Interaction between Apolipoprotein E and Aβ Reduces Intraneuronal Accumulation of Aβ and Inhibits Synaptic Degeneration

Open access
Kuszczyk, Magdalena A., Sanchez, Sandrine, Pankiewicz, Joanna, Kim, Jungsu, Duszczyk, Malgorzata, Guridi, Maitea, Asuni, Ayodeji A., Sullivan, Patrick M. +2 more·2013·The American Journal of Pathology
DOI 10.1016/j.ajpath.2013.01.034PMC PMC3644726
Open this paper in CoChat — free accountOpen PDF

Abstract

Accumulation of β-amyloid (Aβ) in the brain is a key event in Alzheimer disease pathogenesis. Apolipoprotein (Apo) E is a lipid carrier protein secreted by astrocytes, which shows inherent affinity for Aβ and has been implicated in the receptor-mediated Aβ uptake by neurons. To characterize ApoE involvement in the intraneuronal Aβ accumulation and to investigate whether blocking the ApoE/Aβ interaction could reduce intraneuronal Aβ buildup, we used a noncontact neuronal-astrocytic co-culture system, where synthetic Aβ peptides were added into the media without or with cotreatment with Aβ12-28P, which is a nontoxic peptide antagonist of ApoE/Aβ binding. Compared with neurons cultured alone, intraneuronal Aβ content was significantly increased in neurons co-cultured with wild-type but not with ApoE knockout (KO) astrocytes. Neurons co-cultured with astrocytes also showed impaired intraneuronal degradation of Aβ, increased level of intraneuronal Aβ oligomers, and marked down-regulation of several synaptic proteins. Aβ12-28P treatment significantly reduced intraneuronal Aβ accumulation, including Aβ oligomer level, and inhibited loss of synaptic proteins. Furthermore, we showed significantly reduced intraneuronal Aβ accumulation in APPSW/PS1dE9/ApoE KO mice compared with APPSW/PS1dE9/ApoE targeted replacement mice that expressed various human ApoE isoforms. Data from our co-culture and in vivo experiments indicate an essential role of ApoE in the mechanism of intraneuronal Aβ accumulation and provide evidence that ApoE/Aβ binding antagonists can effectively prevent this process.

AI snapshot

Written from the paper’s full text.

TL;DR

Blocking the ApoE/Aβ interaction with Aβ12-28P reduces intraneuronal Aβ accumulation, Aβ oligomer levels, and synaptic protein loss in a neuronal–astrocytic co-culture model. In vivo, ApoE knockout markedly reduces intraneuronal Aβ in APP/PS1 mice, while human ApoE4 targeted replacement increases fibrillar Aβ load compared with ApoE2/ApoE3.

Key findings

  • In primary hippocampal neurons co-cultured with wild-type astrocytes, intraneuronal Aβ1-40 rose to 150.8% ± 3.6% and Aβ1-42 to 227.1% ± 26.4% of neurons cultured alone (P < 0.001 and P < 0.01, respectively); co-culture with ApoE KO astrocytes showed no significant increase (Aβ1-42 at 87.8% ± 6.8%).
  • Aβ12-28P reduced intraneuronal Aβ1-40 and Aβ1-42 to 46.6% ± 4.8% and 82.8% ± 9.0% of neuron-alone levels, respectively; it also reduced intraneuronal Aβ1-40 oligomers from 57.5 ± 8.3 to 30.0 ± 6.3 ng/mg and Aβ1-42 oligomers from 57.5 ± 5.9 to 40.0 ± 6.3 ng/mg (P < 0.05).
  • Co-culture with astrocytes increased intraneuronal Aβ1-40 and Aβ1-42 oligomers by 11.8- and 1.7-fold (P < 0.001), impaired Aβ1-40 degradation (43.7% ± 4.9% remaining at 24 h and 32.9% ± 9.2% at 48 h vs. none detectable at 24 h in neurons alone), and enhanced Aβ1-40-induced loss of NR1, PSD-95, and synaptophysin (76.8%, 80.4%, and 75.3% reductions, respectively).
  • In 11-month-old female APP/PS1/ApoE-TR mice, fibrillar Aβ load was 0.86% ± 0.19% for ApoE2, 1.05% ± 0.18% for ApoE3, and 1.92% ± 0.34% for ApoE4 (P < 0.05 vs. E2/E3); APP/PS1/ApoE KO mice had few intraneuronal Aβ-positive CA1 and CA2/3 pyramidal neurons (1.2% ± 0.3% and 4.3% ± 0.6%) versus 39.7%–45.4% in CA1 and 55.9%–63.1% in CA2/3 across ApoE-TR lines.

Methods

  • Noncontact neuronal–astrocytic co-culture: primary hippocampal neurons from C57BL/6 or ApoE KO mice, astrocytes on Transwell inserts, synthetic HFIP-monomerized Aβ1-40 or Aβ1-42 added at 10 μmol/L for 24 or 72 h, with or without 10 μmol/L Aβ12-28P or scrambled Aβ12-28P S; treatments repeated three to six times.
  • Biochemical and imaging analyses: Western/dot immunoblot, aggregated-Aβ ELISA, confocal microscopy with organelle and synaptic markers, and densitometric quantification; synaptic protein expression measured in at least 20 neurons per group from three independent experiments.
  • In vivo: newly generated APP/PS1/ApoE KO and APP/PS1/ApoE-TR (human ApoE2, E3, E4) mice, 11-month-old females; fibrillar Aβ load quantified by X-34/thioflavine-S stereology (n = 8 per group), and intraneuronal Aβ1-X quantified by 6E10/4G8 and MAP2 double immunofluorescence in CA1 and CA2/3 from five to seven serial sections per brain; statistics used ANOVA with Tukey’s or Bonferroni’s post hoc tests and U-test.

Limitations

  • Not stated in the paper: the article does not include a dedicated limitations section.
  • Evident from the text: the in vitro work relies on synthetic Aβ peptides and primary co-cultures rather than endogenous Aβ, and the in vivo experiments used only female mice because of documented sex differences in Aβ deposition in APP/PS1 mice.
  • Evident from the text: human ApoE isoforms did not significantly differ in the number of intraneuronal Aβ-bearing neurons overall, with a significant isoform difference only in CA2/3 between ApoE2 and ApoE4; the authors also note that 6E10/4G8 can cross-detect APP under certain conditions, although they used controls to support specificity.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.ajpath.2013.01.034

Cites

63 of 63 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

34 of 60 cited sources checked · 16 supported · 2 flagged · accuracy not yet measured

  • Premisecitation

    ApoE has inherent affinity for Aβ.

    “Apolipoprotein E (ApoE) is a 34-kDa lipid carrier protein with inherent affinity for Ab, which is involved in multiple aspects of Ab metabolism, including formation of Ab plaques and CAA and impairment of Ab brain clearance.13”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [13] Kim, 2009, The role of apolipoprotein E in Alzheimer’s disease, Neuron source
  • Premisecitation

    Aβ12-28P inhibits ApoE4/Aβ binding with Ki = 12.9 nmol/L.

    “As we have previously shown, Ab12-28P inhibits ApoE4/Ab binding with K I Z 12.9 nmol/L, neutralizes the promoting effect of ApoE on Ab fibrillization in vitro, and reduces the load of Ab plaques and CAA when systemically administered to APP SW Tg mice.22”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [22] Sadowski, 2006, Blocking the apolipoprotein E/amyloid-beta interaction as a potential therapeutic approach for Alzheimer’s disease, Proc Natl Acad Sci U S A source
  • Premisecitation

    Aβ12-28P neutralizes the promoting effect of ApoE on Aβ fibrillization in vitro.

    “As we have previously shown, Ab12-28P inhibits ApoE4/Ab binding with K I Z 12.9 nmol/L, neutralizes the promoting effect of ApoE on Ab fibrillization in vitro, and reduces the load of Ab plaques and CAA when systemically administered to APP SW Tg mice.22”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [22] Sadowski, 2006, Blocking the apolipoprotein E/amyloid-beta interaction as a potential therapeutic approach for Alzheimer’s disease, Proc Natl Acad Sci U S A source
  • Premisecitation

    Aβ12-28P reduces the load of Aβ plaques and CAA when systemically administered to APPSW Tg mice.

    “As we have previously shown, Ab12-28P inhibits ApoE4/Ab binding with K I Z 12.9 nmol/L, neutralizes the promoting effect of ApoE on Ab fibrillization in vitro, and reduces the load of Ab plaques and CAA when systemically administered to APP SW Tg mice.22”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [22] Sadowski, 2006, Blocking the apolipoprotein E/amyloid-beta interaction as a potential therapeutic approach for Alzheimer’s disease, Proc Natl Acad Sci U S A source
  • Premisecitation

    Intraneuronal accumulation of Aβ is a potentially important aspect of AD pathogenesis.

    “Intraneuronal accumulation of Ab is a potentially important aspect of AD pathogenesis.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [34] Takahashi, 2004, Oligomerization of Alzheimer’s beta-amyloid within processes and synapses of cultured neurons and brain, J Neurosci source
  • May combine two claims. 42
  • Classified as probably not a substantial claim. 24
  • The quote only partly states this claim. 3

  • May combine two claims.

    Premisecitation

    Evidence suggests that internalization of Aβ not associated with ApoE occurs through nonendocytotic mechanisms, based on translocation of cell surface bound Aβ directly to the cytosol, and results in accumulation of Aβ primarily outside the endosomal/lysosomal compartment.

    “In contrast, evidence suggests that internalization of Ab not associated with ApoE occurs through nonendocytotic mechanisms, which are based on the translocation of the cell surface bound Ab directly to the cytosol and results in accumulation of Ab primarily outside the endosomal/lysosomal compartment.28,45,46”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [28] Takuma, 2009, RAGE-mediated signaling contributes to intraneuronal transport of amyloid-beta and neuronal dysfunction, Proc Natl Acad Sci U S A source
    • cites [45] Saavedra, 2007, Internalization of beta-amyloid peptide by primary neurons in the absence of apolipoprotein E, J Biol Chem source

      Split into 2 atoms — 0 confirmed, 0 partially supported, 2 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
    • cites [46] Kandimalla, 2009, Mechanism of neuronal versus endothelial cell uptake of Alzheimer’s disease amyloid beta protein, PLoS One source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In this model, Aβ accumulates along the endosomal/lysosomal pathway that leads to dysfunction of multivesicular bodies, causing impairment of the ubiquitin-proteasome system, which also controls the fate of NMDARs undergoing endocytic vesicular trafficking.

    “In this model, Ab accumulates along the endosomal/lysomal pathway that leads to dysfunction of multivesicular bodies, causing impairment of the ubiquitin-proteasome system, 9 which also controls the fate of NMDARs undergoing endocytic vesicular trafficking.50”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [9] Almeida, 2006, Beta-amyloid accumulation impairs multivesicular body sorting by inhibiting the ubiquitin-proteasome system, J Neurosci source

      Split into 2 atoms — 1 confirmed, 0 partially supported, 1 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
    • cites [50] Perez-Otano, 2005, Homeostatic plasticity and NMDA receptor trafficking, Trends Neurosci source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Intraneuronal Aβ buildup has been associated with hyperphosphorylation of tau protein.

    “A number of studies have associated intraneuronal Ab buildup with hyperphosphorylation of tau protein, 8 disturbed protein trafficking and sorting, 9 reduced expression of synaptic proteins, 10 and mitochondrial dysfunction.11,12”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [8] Takahashi, 2010, Co-occurrence of Alzheimer’s disease beta-amyloid and tau pathologies at synapses, Neurobiol Aging source

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductcitation

    Given documented sex differences in Aβ deposition in the APPSW/PS1dE9 strain, the load of Aβ plaques and intraneuronal Aβ accumulation were quantified only in female mice.

    “Given documented sex differences in Ab deposition in the APP SW / PS1 dE9 strain, 21 the load of Ab plaques and intraneuronal Ab accumulation were quantified only in female mice.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [21] Kim, 2009, Overexpression of low-density lipoprotein receptor in the brain markedly inhibits amyloid deposition and increases extracellular A beta clearance, Neuron source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Intraneuronal Aβ buildup has been associated with mitochondrial dysfunction.

    “A number of studies have associated intraneuronal Ab buildup with hyperphosphorylation of tau protein, 8 disturbed protein trafficking and sorting, 9 reduced expression of synaptic proteins, 10 and mitochondrial dysfunction.11,12”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [11] Lustbader, 2004, ABAD directly links Abeta to mitochondrial toxicity in Alzheimer’s disease, Science source
    • cites [12] Zepa, 2011, ApoE4-driven accumulation of intraneuronal oligomerized Abeta42 following activation of the amyloid cascade in vivo is mediated by a gain of function, Int J Alzheimers Dis source

  • May combine two claims.

    Premisecitation

    Aβ12-28P is a nontoxic, synthetic peptide modified for increased BBB permeability and extended serum half-life.

    “The ApoE/Ab binding was blocked with Ab12-28P, which is a nontoxic, synthetic peptide modified for increased blood-brain-barrier (BBB) permeability and extended serum half-life.16”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] Sadowski, 2004, A synthetic peptide blocking the apolipoprotein E/beta-amyloid binding mitigates beta-amyloid toxicity and fibril formation in vitro and reduces beta-amyloid plaques in transgenic mice, Am J Pathol source

      The Synthetic Peptides and Proteins section describes Aβ12-28P as synthetic and modified to extend its half-life; the introductory passage says a sequence substitution made it nontoxic. The Pharmacokinetic and Blood-Brain Barrier Permeability Studies section shows that it crosses the BBB, but does not say the modifications increased BBB permeability; its measured distribution did not differ significantly from the comparator. Page numbers are unavailable in our copy. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    ApoE is involved in multiple aspects of Aβ metabolism, including formation of Aβ plaques and CAA and impairment of Aβ brain clearance.

    “Apolipoprotein E (ApoE) is a 34-kDa lipid carrier protein with inherent affinity for Ab, which is involved in multiple aspects of Ab metabolism, including formation of Ab plaques and CAA and impairment of Ab brain clearance.13”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [13] Kim, 2009, The role of apolipoprotein E in Alzheimer’s disease, Neuron source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The Aβ plaque load in the neocortex was quantified on X-34-stained sections in a blinded manner according to unbiased stereologic principles.

    “The Ab plaque load in the neocortex (percentage of cross-sectional area covered by Ab) was quantified on X-34-stained sections in a blinded manner according to unbiased stereologic principles (Cavalieri-point counting method) as previously published.21”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [21] Kim, 2009, Overexpression of low-density lipoprotein receptor in the brain markedly inhibits amyloid deposition and increases extracellular A beta clearance, Neuron source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Intraneuronal Aβ buildup has been associated with disturbed protein trafficking and sorting.

    “A number of studies have associated intraneuronal Ab buildup with hyperphosphorylation of tau protein, 8 disturbed protein trafficking and sorting, 9 reduced expression of synaptic proteins, 10 and mitochondrial dysfunction.11,12”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [9] Almeida, 2006, Beta-amyloid accumulation impairs multivesicular body sorting by inhibiting the ubiquitin-proteasome system, J Neurosci source

  • May combine two claims.

    Premisecitation

    LRP overexpression in APP V717F mice augmented intraneuronal Aβ accumulation, exacerbated memory deficit, and caused an increase in soluble Aβ level in the brain.

    “LRP overexpression in APP V717F mice, besides augmenting intraneuronal Ab accumulation, exacerbated the memory deficit and caused an increase in soluble Ab level in the brain.41”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [41] Zerbinatti, 2004, Increased soluble amyloid-beta peptide and memory deficits in amyloid model mice overexpressing the low-density lipoprotein receptor-related protein, Proc Natl Acad Sci U S A source

      Materials and Methods identifies the mice as carrying APPV717F and mLRP2 transgenes. The Results report higher soluble brain Aβ and worse water-maze performance in PDAPP/LRP+ mice than in controls, but do not establish increased intraneuronal Aβ accumulation; the reported Aβ measurements are from brain extracts. Page numbers are unavailable in our copy. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    APP/PS1/LDLR mice showed increased clearance of Aβ from the extracellular space and inhibition of Aβ deposition.

    “APP SW /PS1 dE9 /LDLR mice showed increased clearance of Ab from the extracellular space and inhibition of Ab deposition.21”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [21] Kim, 2009, Overexpression of low-density lipoprotein receptor in the brain markedly inhibits amyloid deposition and increases extracellular A beta clearance, Neuron source

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Several recent studies provided evidence to support increased content of Aβ oligomers in the extracellular space in brains of patients with AD expressing human ApoE4 isoform, and intraneuronally in mice expressing human ApoE4 isoform after inhibition of Aβ-degrading enzyme neprilysin.

    “Several recent studies provided evidence to support increased content of Ab oligomers in the extracellular space in brains of patients with AD, expressing the human ApoE4 isoform, 37,38 and intraneuronally in mice expressing human ApoE4 isoform after inhibition of Ab-degrading enzyme neprilysin.39”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [37] Hashimoto, 2012, Apolipoprotein E, especially apolipoprotein E4, increases the oligomerization of amyloid beta peptide, J Neurosci source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [38] Koffie, 2012, Apolipoprotein E4 effects in Alzheimer’s disease are mediated by synaptotoxic oligomeric amyloid-beta, Brain source
    • cites [39] Belinson, 2008, Activation of the amyloid cascade in apolipoprotein E4 transgenic mice induces lysosomal activation and neurodegeneration resulting in marked cognitive deficits, J Neurosci source

      The ‘Intraneuronal accumulation of Aβ and ApoE’ section reports increased Aβ staining in CA1 neurons of apoE4 mice after neprilysin inhibition, supporting the mouse finding attributed to this source (citation 39). It does not identify the intraneuronal Aβ as oligomers. The patient finding is attached to citations 37 and 38, not this paper. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Thus far, the differential effect of targeted ApoE isoform replacement on Aβ pathology has been reproduced in single APP V717F mice, which had to be at least 18 months of age to observe substantial Aβ load.

    “Thus far, the differential effect of targeted ApoE isoform replacement on Ab pathology has been reproduced in single APP V717F mice, which had to be at least 18 months of age to observe substantial Ab load.56,57”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [56] Bales, 2009, Human APOE isoform-dependent effects on brain beta-amyloid levels in PDAPP transgenic mice, J Neurosci source
    • cites [57] Castellano, 2011, Human apoE isoforms differentially regulate brain amyloid-β peptide clearance, Sci Transl Med source

      The Animals section identifies the mice as APP V717F PDAPP mice expressing human ApoE isoforms, and the Results section reports isoform-dependent Aβ deposition at 20–21 months (page numbers unavailable). The paper does not establish that mice had to be at least 18 months old to show substantial Aβ load. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Interpretationcitation

    Published data indicate that the ApoE/Aβ interaction may result in multidirectional effects that may promote Aβ degradation by nonneuronal cells while enhancing Aβ accumulation in neurons.

    “These published data indicate that the ApoE/Ab interaction may result in multidirectional effects that may promote Ab degradation by nonneuronal cells 43,44 while enhancing Ab accumulation in neurons.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [43] Jiang, 2008, ApoE promotes the proteolytic degradation of Abeta, Neuron source
    • cites [44] Cramer, 2012, ApoE-directed therapeutics rapidly clear beta-amyloid and reverse deficits in AD mouse models, Science source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    APOE alleles are a well-recognized genetic risk factor for sporadic AD and correlate with severity of β-amyloidosis.

    “The APOE alleles are a well-recognized genetic risk factor for sporadic AD and correlate with severity of b-amyloidosis.13”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [13] Kim, 2009, The role of apolipoprotein E in Alzheimer’s disease, Neuron source

  • May combine two claims.

    Premisecitation

    Several AD Tg animal models are characterized by early and massive intraneuronal accumulation of Aβ oligomers, loss of synaptic proteins, and behavioral impairment which occur in the absence of extracellular Aβ plaques.

    “Furthermore, several AD Tg animal models are characterized by early and massive intraneuronal accumulation of Ab oligomers, loss of synaptic proteins, and behavioral impairment which occur in the absence of extracellular Ab plaques.7,51”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [7] Oakley, 2006, Intraneuronal beta-amyloid aggregates, neurodegeneration, and neuron loss in transgenic mice with five familial Alzheimer’s disease mutations: potential factors in amyloid plaque formation, J Neurosci source

      The Introduction (page not supplied) reports intraneuronal Aβ accumulation before plaques form in 5XFAD mice, along with reduced synaptic markers and memory impairment. But the Memory impairment section says 5XFAD mice had no Y-maze deficit at two months, when intraneuronal Aβ was already accumulating; their deficit appeared at four to five months, after plaques appeared. The paper therefore does not support the claim that all three features occur together in the absence of extracellular plaques. (LLM, conf=0.90)

      Experimental — accuracy not yet measured
    • cites [51] Knobloch, 2007, Intracellular Abeta and cognitive deficits precede beta-amyloid deposition in transgenic arcAbeta mice, Neurobiol Aging source

  • May combine two claims.

    Premisecitation

    Aβ12-28P is a nontoxic synthetic peptide modified for in vivo application, and its blood-brain barrier permeability was previously evaluated and reported.

    “Ab12-28P is a nontoxic synthetic peptide that was modified for in vivo application, and its BBB permeability was previously evaluated and reported.16”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] Sadowski, 2004, A synthetic peptide blocking the apolipoprotein E/beta-amyloid binding mitigates beta-amyloid toxicity and fibril formation in vitro and reduces beta-amyloid plaques in transgenic mice, Am J Pathol source

  • May combine two claims.

    Premisecitation

    These cultures are characterized by progressive buildup of intraneuronal Aβ, which is derived from endogenous Aβ escaping exocytosis after cleavage of the APP SW mutant.

    “These cultures are characterized by progressive buildup of intraneuronal Ab, which is derived from endogenous Ab escaping exocytosis after cleavage of the APP SW mutant.9,49”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [9] Almeida, 2006, Beta-amyloid accumulation impairs multivesicular body sorting by inhibiting the ubiquitin-proteasome system, J Neurosci source

      The section on Aβ42 localization in cultured APP-mutant neurons reports intracellular Aβ42 staining in neurons carrying the Swedish APP mutation and describes staining for endogenous Aβ42. The Introduction describes APP cleavage as a possible route to Aβ production. Neither passage establishes progressive buildup in these cultures or that the retained Aβ escaped exocytosis. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [49] Snyder, 2005, Regulation of NMDA receptor trafficking by amyloid-beta, Nat Neurosci source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    It has been previously reported that extracellular application of Aβ oligomers to primary neuronal cultures or organotypic hippocampal slices induce rapid changes in structure and density of synaptic spines and reduces expression of NMDARs and related synaptic proteins through several signaling pathways, one of which involves the α-7 nicotinic receptor.

    “It has been previously reported that extracellular application of Ab oligomers to primary neuronal cultures or organotypic hippocampal slices induce rapid changes in the structure and density of synaptic spines 47,48 and reduces expression of NMDARs and related synaptic proteins, 49 through several signaling pathways, one of which involves the a-7 nicotinic receptor.49”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites [47] Lacor, 2007, Abeta oligomer-induced aberrations in synapse composition, shape, and density provide a molecular basis for loss of connectivity in Alzheimer’s disease, J Neurosci source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [48] Shankar, 2007, Natural oligomers of the Alzheimer amyloid-beta protein induce reversible synapse loss by modulating an NMDA-type glutamate receptor-dependent signaling pathway, J Neurosci source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [49] Snyder, 2005, Regulation of NMDA receptor trafficking by amyloid-beta, Nat Neurosci source

  • The quote only partly states this claim.

    Findingown data

    Addition of Aβ12-28P (10 μmol/L) with Aβ1-40 to neuronal-astrocytic co-cultures reduced intraneuronal Aβ1-40 to 46.6% ± 4.8% of that in neurons cultured alone (P < 0.001).

    “intraneuronal levels of Ab1-40 and Ab1-42 peptides were reduced to 46.6% Æ 4.8% (P < 0.001) and 82.8% Æ 9.0%, respectively (P < 0.01), of those in neurons cultured alone.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Astrocytes produce and secrete ApoE.

    “Production of ApoE by astrocytes was confirmed with Western immunoblot analysis with HJ6.1 mAb against murine ApoE in astrocytic lysates and media (Figure 1D).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In co-cultures using ApoE KO astrocytes, intraneuronal Aβ1-42 level was 87.8% ± 6.8% of that in neurons cultured alone, and with Aβ12-28P it was 93.0% ± 10.9%, with no statistically significant differences.

    “Ab1-42 level in neurons cocultured with ApoE KO astrocytes was at 87.8% Æ 6.8% of the Ab1-42 level of neurons cultured alone, whereas, in neurons co-cultured with astrocytes and additionally treated with Ab12-28P, the intraneuronal Ab1-42 level was at 93.0% Æ 10.9% of the Ab1-42 level of neurons cultured alone (differences statistically not significant)”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Astrocytes derived from ApoE KO mice do not produce ApoE.

  • May combine two claims.

    Findingown data

    AβX-42 carboxyterminal immunostaining produced a fine, granular pattern associated with a large fraction of pyramidal neurons in APP/PS1/ApoE-TR mice but with few neurons in APP/PS1/ApoE KO mice, akin to that observed with 6E10/4G8 mAb staining.

    “Ab X-42 carboxyterminal immunostaining produced a fine, granular pattern that was associated with a large fraction of pyramidal neurons in APP SW /PS1 dE9 /ApoE-TR mice but with few neurons in APP SW /PS1 dE9 /ApoE KO mice, akin to that observed with 6E10/4G8 mAb staining.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    APP/PS1/ApoE KO mice had little true amyloid deposits shown by X-34 or thioflavin-S; scant deposits were too rare and too small to be reliably thresholded and quantified.

    “APP SW PS1 dE9 /ApoE KO mice had little true amyloid deposits shown by amyloid-binding dyes X-34 or thioflavin-S.Scant deposits were too rare and too small to be reliably thresholded and quantified”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Primary hippocampal neurons cultured alone degraded 50% of internalized Aβ1-40 within 3.2 hours, and no Aβ1-40 was detectable in their lysates at 24 hours after washout.

    “Primary hippocampal neuron culture alone degraded 50% of the internalized Ab1-40 within 3.2 hours, and no Ab1-40 was detectable in their lysates at 24 hours after the commencement of the washout period.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Neurons co-cultured with astrocytes showed a substantial increase in intraneuronal Aβ1-40 content compared with neurons cultured alone, particularly in late endosomes and lysosomes, and to a lesser extent in early endosomes and mitochondria.

    “In contrast neurons co-cultured with astrocytes showed a substantial increase in the intraneuronal content of Ab1-40 compared with neurons cultured alone.In neurons from the neuronal-astrocytic co-cultures, the Ab1-40 content was particularly increased in late endosomes and in lysosomes (Figure 6C and Supplemental Figure S5C).To less extent, Ab1-40 colocalized with markers for early endosomes and”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Both anti-APP Abs produced robust staining of virtually all CA1 and CA2/3 pyramidal neurons in APP/PS1/ApoE KO mice, comparable with that seen in APP/PS1/ApoE-TR mice.

    “Both anti-APP Abs produced robust staining of virtually all CA1 and CA2/3 pyramidal neurons in APP SW /PS1 dE9 /ApoE KO mice, which was comparable with that seen in APP SW /PS1 dE9 /ApoE-TR mice.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In primary hippocampal neurons cultured alone, most Aβ1-40 was found outside neurons as fine aggregates covering the external surface of dendrites, with a small amount inside neuronal perikarya.

    “In primary hippocampal neurons cultured alone, most of the Ab1-40 was found outside neurons visible in the form of fine aggregates that covered the external surface of their dendrites (Figure 5A).A small amount of Ab1-40 was also found inside neuronal perikarya”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Aβ12-28P treatment of neurons co-cultured with astrocytes inhibited the loss of synaptic proteins; compared with co-cultures without Aβ1-40, expression of NR1, PSD-95, and synaptophysin was reduced only by 29%, 26.1%, and 36.5%, respectively (P < 0.001).

    “Ab12-28P treatment of neurons co-cultured with astrocytes inhibited the loss of synaptic proteins.Compared with the primary hippocampal neurons co-cultured with astrocytes in the absence of Ab1-40, expression of the NR1 subunit of NMDAR, PSD-95, and synaptophysin was reduced only by 29%, 26.1%, and 36.5%,respectively (P < 0.001)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In neurons co-cultured with astrocytes, a significantly smaller number of Aβ1-40 aggregates were seen on the external surface of dendrites, and large Aβ1-40 aggregates were present inside neurons, in perikarya and proximal dendrites.

    “In contrast, in neurons co-cultured with astrocytes, a significantly smaller number of Ab1-40 aggregates were seen on the external surface of dendrites (Figure 5D).Instead, confocal microscopy tomograms taken at the level of perikarya showed large Ab1-40 aggregates present inside the neurons.They were clearly visualized inside the perikarya and in proximal segments of the primary dendrites”
    Quote in the paperSubstantial claim

  • May combine two claims. The quote only partly states this claim.

    Findingown data

    After 6 hours of exposure to 10 μmol/L Aβ1-40, the Aβ1-40 signal was seen only in astrocytic lysate at the conclusion of exposure, and no Aβ1-40 signal was detectable within 2 hours after washout.

    “After 6 hours of exposure to 10 mmol/L Ab1-40, the Ab1-40 signal was seen only in the astrocytic lysate at the conclusion of the Ab exposure, whereas no Ab1-40 signal was detectable within t Z 2 hours after commencement of the washout period”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    Fibrillar Aβ load in the neocortex differs between APP SW/PS1 dE9/ApoE-TR mice homozygous for the E2, E3, and E4 alleles.

    “B: Unbiased quantification of the fibrillar Ab load in the neocortex of 11-month-old female APP SW /PS dE9 / ApoE-TR mice, which are homozygotes for E2, E3, and E4 alleles.Values are given as means Æ SEM (n Z 8 per group).Statistical significance between particular transgenic lines was analyzed with U-test, whose values, if significant, are depicted in the figure.*P < 0.05.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The number of Aβ 1-X-positive neurons in the CA1 and CA2/CA3 sectors of the cornu ammonis differs between APP SW/PS1 dE9/ApoE KO and APP SW/PS1 dE9/ApoE-TR lines and among ApoE isoforms.

    “B: Quantitative analysis of Ab 1-X -positive neurons in the CA1 and CA2/CA3 sectors of the cornu ammonis in APP SW /PS dE9 /ApoE KO and APP SW /PS dE9 / ApoE-TR lines.Analysis of variance P < 0.0001 for both sectors and ApoE isoform effect.Values of the post hoc analysis that used Bonferroni's test are displayed on the graph for pairs of columns with statistically significant differences.**P < 0.0”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Treatment with Aβ12-28P markedly reduces intraneuronal Aβ1-40 content, especially in late endosomes and lysosomes.

    “D: Representative microphotographs of primary hippocampal neurons co-cultured with astrocytes that were treated with Ab12-28P during the exposure to Ab1-40/FITC-Ab1-40.There is markedly reduced intraneuronal Ab1-40 content, especially in the late endosomes and lysosomes.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Blocking the ApoE/Aβ interaction with Aβ12-28P inhibits loss of synaptic proteins.

    “We demonstrated that blocking the ApoE/Ab interaction with the use of Ab12-28P reduces intraneuronal Ab1-40 and Ab1-42 accumulation, including levels of intraneuronal Ab1-40 and Ab1-42 oligomers, and inhibits loss of synaptic proteins.”
    • Also stated in: § ajp.amjpathol.org -The American Journal of Pathology · plain
      “F: Quantitative analysis of synaptic protein expression.Values show means Æ SD density of synaptic proteins along primary and secondary dendrites relative to those in primary hippocampal neurons cultured alone without AbÀ40 in three independent experiments.One-way analysis of variance P < 0.0001 for all three synaptic proteins.Post hoc Tukey' s HSD test values are displayed on the graph for pairs”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In primary hippocampal neurons, intraneuronal Aβ1-40 and Aβ1-42 levels differed significantly across culture and treatment conditions (ANOVA P<0.0001 and P=0.0006, respectively).

    “Values in the graphs show the mean percentage Æ SEM of Ab1-40 and Ab1-42 band optic densities relative to those in neurons cultured alone during exposure to Ab peptides (lane 2) in five and four independent experiments that used Ab1-40 (analysis of variance P < 0.0001) and Ab1-42 (analysis of variance P Z 0.0006), respectively.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Cultures that showed a purity of at least 90% were grown further until 14 DIV.

    “Those cultures that showed a purity of at least 90% were grown further until 14 DIV when neurons reach their mature form and express functional glutamatergic receptors.25”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] Mattson, 1991, Developmental expression. compartmentalization, and possible role in excitotoxicity of a putative NMDA receptor protein in cultured hippocampal-neurons, Brain Res source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Intraneuronal Aβ buildup has been associated with reduced expression of synaptic proteins.

    “A number of studies have associated intraneuronal Ab buildup with hyperphosphorylation of tau protein, 8 disturbed protein trafficking and sorting, 9 reduced expression of synaptic proteins, 10 and mitochondrial dysfunction.11,12”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [10] Almeida, 2005, Beta-amyloid accumulation in APP mutant neurons reduces PSD-95 and GluR1 in synapses, Neurobiol Dis source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    Cultures containing 90% or more GFAP-positive astrocytes were used for co-culture experiments.

    “Cultures containing 90% or more glial fibrillary acidic protein-positive astrocytes were used for co-culture experiments (Figure 1B).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    All mouse care and experimental procedures were approved by Institutional Animal Care and Use Committees.

    “All mouse care and experimental procedures were approved by Institutional Animal Care and Use Committees of the New York University School of Medicine and the Washington University School of Medicine.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Intraneuronal Aβ accumulation may contribute importantly to the Aβ-induced neurodegenerative cascade.

    “There is also evidence of intraneuronal Ab accumulation in addition to the extracellular Ab plaques and CAA, which may also contribute importantly to the Ab-induced neurodegenerative cascade.5e7”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 5e7

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    All mice that were compared were on the same genetic background.

    “All mice that were compared were on the same genetic background.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Each treatment experiment in neuronal-astrocytic co-cultures or neuronal monocultures was repeated three to six times.

    “Each treatment experiment in neuronal-astrocytic co-cultures or neuronal monocultures was repeated three to six times.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationown data

    Some Aβ1-40 was seen outside the nuclear envelope and did not colocalize with any of the organelle markers, suggesting possible cytoplasmic localization.

    “Furthermore, some Ab1-40 was seen outside the nuclear envelope and did not show colocalization with any of the aforementioned organelle markers, which suggested its possible cytoplasmic localization.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    This equilibrium is further affected by Aβ clearance into cerebrospinal fluid and across the BBB.

    “This equilibrium is further affected by Ab clearance into cerebrospinal fluid and across the BBB.35”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [35] Deane, 2004, RAGE (Yin) versus LRP (Yang) balance regulates Alzheimer amyloid beta-peptide clearance through transport across the blood-brain barrier, Stroke source

  • May combine two claims.

    Interpretationown data

    These experiments confirmed robust Aβ clearance and intracellular degradation capacity of astrocytes.

    “These experiments confirmed robust Ab clearance and intracellular degradation capacity of astrocytes.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    Disequilibrium between the rate of intraneuronal Aβ accumulation and intraneuronal Aβ degradation in AD neurons results in its intraneuronal buildup.

    “Disequilibrium between the rate of intraneuronal Ab accumulation and intraneuronal Ab degradation in AD neurons results in its intraneuronal buildup.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    The protective effect of LDLR up-regulation can be related to the receptor subtype and/or its overexpression in nonneuronal cells capable of efficient Aβ degradation.

    “These mice overexpress LDLR in neurons and astrocytes, which indicates that the protective effect of LDLR up-regulation can be related to the receptor subtype and/or its overexpression in nonneuronal cells capable of efficient Ab degradation.42”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [42] Basak, 2012, Low-density lipoprotein receptor represents an apolipoprotein E-independent pathway of Abeta uptake and degradation by astrocytes, J Biol Chem source

  • May combine two claims.

    Interpretationown data

    Aβ12-28P treatment had no effect on intraneuronal Aβ level in neurons cultured alone, indicating that ApoE is required for its pharmacodynamic effect.

    “Furthermore, Ab12-28P treatment had no effect on the intraneuronal Ab level in primary hippocampal neurons cultured alone, which again indicates that ApoE is required for its pharmacodynamic effect.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    ApoE can greatly increase the tempo of Aβ internalization by binding Aβ in the extracellular space and directing it to neurons, which internalize ApoE/Aβ complexes through highly efficient receptor-mediated endocytosis.

    “However, ApoE can greatly increase the tempo of Ab internalization by binding Ab in the extracellular space and directing it to neurons, which internalize ApoE/Ab complexes through highly efficient receptor-mediated endocytosis.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    ApoE facilitates but is not required for Aβ uptake, because neurons grown in the absence of ApoE can internalize Aβ.

    “As shown by us and others, ApoE facilitates but it is not required for Ab uptake, because neurons grown in the absence of ApoE can internalize Ab. 28”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [28] Takuma, 2009, RAGE-mediated signaling contributes to intraneuronal transport of amyloid-beta and neuronal dysfunction, Proc Natl Acad Sci U S A source

  • May combine two claims.

    Interpretationreasoning

    APP/PS1/ApoE-TR mice represent an important advance in modeling the effect of human ApoE isoforms on Aβ pathology, allowing studies on novel AD therapeutics in animals of much younger age.

    “Thus, APP SW /PS1 dE9 /ApoE-TR mice represent an important advance in modeling the effect of human ApoE isoforms on Ab pathology, allowing us to conduct studies, for example, on novel AD therapeutics, in animals of much younger age.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    In 3xTg-AD mice, intraneuronal Aβ accumulation may predate formation of Aβ plaques and neurofibrillary pathology and shows temporal correlation with synaptic dysfunction, emphasizing the role of intraneuronal Aβ in neurodegeneration.

    “In particular, in 3ÂTg-AD mice (APP SW /PS1 M146V /Tau P301L ), intraneuronal Ab accumulation may predate formation of Ab plaques and neurofibrillary pathology and shows temporal correlation with synaptic dysfunction, emphasizing the role of intraneuronal Ab in neurodegeneration.52,53”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [52] Oddo, 2003, Triple-transgenic model of Alzheimer’s disease with plaques and tangles: intracellular Abeta and synaptic dysfunction, Neuron source
    • cites [53] Billings, 2005, Intraneuronal Abeta causes the onset of early Alzheimer’s disease-related cognitive deficits in transgenic mice, Neuron source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Inheritance of APOE4 increases AD risk, whereas APOE2 shows a relative protective effect.

    “Inheritance of APOE4 increases AD risk, whereas APOE2 shows a relative protective effect.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The APP/PS1 line represents a Tg model with enhanced disease phenotype, whereby the first plaques are detected by thioflavin-S at the age of 4 months.

    “The APP SW /PS1 dE9 line represents a Tg model with enhanced disease phenotype, whereby the first plaques are detected by thioflavin-S at the age of 4 months.54”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [54] Garcia-Alloza, 2006, Characterization of amyloid deposition in the APPswe/PS1dE9 mouse model of Alzheimer disease, Neurobiol Dis source

  • May combine two claims.

    Interpretationown data

    Confocal microscopy imaging of neurons from astrocytic co-cultures showed increased Aβ content in the endosomal/lysosomal compartment, which is consistent with internalization of ApoE/Aβ complexes through receptor-mediated endocytosis, directing the complex to the endosomal/lysosomal system.

    “Confocal microscopy imaging of neurons from astrocytic co-cultures showed increased Ab content in the endosomal/ lysosomal compartment, which is consistent with internalization of ApoE/Ab complexes through receptor-mediated endocytosis, directing the complex to the endosomal/ lysosomal system.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    Quantification of fibrillar Aβ load in the neocortex was performed using an unbiased stereologic principle.

    “calculating the average load of fibrillar Ab deposits in the neocortex in 11-month-old female mice with the use of an unbiased stereologic principle.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Aβ12-28P treatment of neurons co-cultured with astrocytes reduced intraneuronal levels of Aβ peptides below that detected in neurons cultured alone, because it blocked ApoE-mediated Aβ internalization, whereas ApoE-independent Aβ uptake was limited because of reduced Aβ concentration in the conditioned media.

    “Ab12-28P treatment of neurons co-cultured with astrocytes reduced the intraneuronal levels of Ab peptides below that detected in neurons cultured alone, because it blocked ApoE-mediated Ab internalization, whereas ApoE-independent Ab uptake was limited because of reduced Ab concentration in the conditioned media.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    ApoE-promoted buildup of Aβ oligomers along the endosomal/lysosomal pathway may therefore affect intracellular trafficking and sorting of synaptic proteins and may indicate a way in which intracellular Aβ contributes to synaptic degeneration.

    “ApoE-promoted buildup of Ab oligomers along the endosomal/lysosomal pathway may therefore affect intracellular trafficking and sorting of synaptic proteins and may indicate a way in which intracellular Ab contributes to synaptic degeneration.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Similar effects of ApoE KO were previously reported in APP V717F and APP SW lines, representing more latent models of Aβ pathology in which thioflavin-S detects the first plaques around the age of 1 year.

    “Similar effects of the ApoE KO were previously reported in APP V717F and APP SW lines, representing more latent models of Ab pathology in which thioflavin-S detects the first plaques around the age of 1 year.14,55”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [14] Bales, 1997, Lack of apolipoprotein E dramatically reduces amyloid β-peptide deposition, Nat Genet source
    • cites [55] Holtzman, 2000, Apolipoprotein E facilitates neuritic and cerebrovascular plaque formation in an Alzheimer’s disease model, Ann Neurol source
60 of 60

  • The paper relies on this without support.

    The noncontact neuronal-astrocytic co-culture system with synthetic Aβ peptides added to the media models intraneuronal Aβ accumulation relevant to Alzheimer disease.

    “we developed a noncontact, co-culture model that combined primary hippocampal neurons and astrocytes as a source of native, lipidated ApoE particles (Figure 1).”

  • The paper relies on this without support.

    ApoE knockout astrocytes do not produce ApoE.

    “Additional astrocytic cultures were established from ApoE KO mice described previously.17 20”

  • The paper relies on this without support.

    The effects of Aβ12-28P on intraneuronal Aβ accumulation and synaptic proteins are due to blocking the ApoE/Aβ interaction.

    “The ApoE/Ab binding was blocked with Ab12-28P, which is a nontoxic, synthetic peptide modified for increased blood-brain-barrier (BBB) permeability and extended serum half-life.16”
    “cotreatment with Ab12-28P, which is a nontoxic peptide antagonist of ApoE/Ab binding.”

  • The paper relies on this without support.

    Astrocytes derived from ApoE KO mice do not produce ApoE.

    “astrocytes derived from ApoE KO mice, which were on the C57BL/6 background”

  • The paper relies on this without support.

    The scrambled peptide Aβ12-28P S is a valid inactive control for Aβ12-28P.

    “Ab12-28P S , a control peptide that represents a scrambled sequence of Ab12-28P”

  • The paper relies on this without support.

    The noncontact neuronal-astrocytic co-culture model ensures that observed effects are due to secreted factors rather than direct cell contact.

    “we set up a noncontact, neuronal-astrocytic coculture model”

  • The paper relies on this without support.

    Lack of ApoE does not affect non-ApoE-mediated pathways of Aβ uptake or accrual of endogenous Aβ remnants from APP cleavage.

    “Because lack of ApoE should not have any effect on the noneApoEmediated pathways of Ab uptake and accrual of endogenous Ab remnants from APP cleavage, this experiment provides evidence to support the pivotal role of ApoE in intraneuronal Ab accumulation, complementing our ex vivo data.”
7 of 7

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • In several AD Tg mouse models, lack of apoE is associated with absence of fibrillar Aβ deposits and prevented neurodegeneration.

    “Our findings remain consistent with the effects of apoE knock-out noted in several AD Tg mouse models, where lack of apoE was associated with absence of fibrillar Aβ deposits and prevented neurodegeneration [13,29,31,32].”

    From Blocking the apoE/Aβ interaction ameliorates Aβ-related pathology in APOE ε2 and ε4 targeted replacement Alzheimer model mice (2014) · cites this paper as [13]

    The paper’s discussion reports a virtual absence of fibrillar Aβ deposits after ApoE knockout in APP SW/PS1 dE9 mice and similar effects in two other AD transgenic lines. Its results also report reduced intraneuronal Aβ, but the passages do not establish that ApoE knockout prevented neurodegeneration; the paper attributes benefits for neurodegeneration to pharmacologic targeting of the ApoE–Aβ interaction. Page numbers are unavailable in our copy. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

  • A small molecule mimetic homologous to the domain of Aβ that interacts with APOE but modified to be more protease-resistant can reduce the oligomerization of Aβ in vitro and ameliorate Aβ and tau pathology in a triple transgenic mouse model of AD.

    “this has been achieved using a small molecule mimetic homologous to the domain of Aβ that interacts with APOE but is modified to be more protease-resistant. This small peptide can reduce the oligomerization of Aβ in vitro and ameliorate Aβ and tau pathology in a triple transgenic mouse model of AD193,194”

    From Multifaceted roles of APOE in Alzheimer disease (2024) · cites this paper as [193]

    Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

    Experimental — accuracy not yet measured

  • An Aβ 12-28 synthetic peptide, which contains the apoE-binding site, reduced cerebral Aβ accumulation in animal models of Aβ amyloidosis.

    “an Aβ 12–28 synthetic peptide, which contains the apoE-binding site, reduced cerebral Aβ accumulation in animal models of Aβ amyloidosis (Kuszczyk et al., 2013; Pankiewicz et al., 2014; Sadowski et al., 2004; 2006).”

    From Apolipoprotein E in Synaptic Plasticity and Alzheimer’s Disease: Potential Cellular and Molecular Mechanisms (2014) · cites this paper as Kuszczyk et al., 2013

  • Human APOE alleles targeted to APPSW/PS1dE9 mice reproduce their differential effect on the magnitude of Aβ plaque load but do not delay onset of Aβ deposition compared to APPSW/PS1dE9 mice expressing native murine apoE.

    “As previously shown, human APOE alleles targeted to APPSW/PS1dE9 mice reproduce their differential effect on the magnitude of Aβ plaque load [13] but do not delay onset of Aβ deposition compared to APPSW/PS1dE9 mice expressing native murine apoE [14].”

    From Blocking the apoE/Aβ interaction ameliorates Aβ-related pathology in APOE ε2 and ε4 targeted replacement Alzheimer model mice (2014) · cites this paper as [13]

    The cited paper reports plaque-load differences among human APOE targeted-replacement mice in its Results section, but citation [14] is attached to the separate claim about the onset of Aβ deposition. The paper mentions first plaques at four months in the APPsw/PS1dE9 model, but the passages found do not compare onset in targeted-replacement mice with onset in mice expressing native murine apoE (page unavailable). (LLM, conf=0.72)

    Experimental — accuracy not yet measured

  • Expression of different isoforms of human ApoE in transgenic mice results in different levels of plaque and CAA burden with apoE4 expression enhancing amyloid deposition compared to apoE3 or apoE2.

    “This is further complicated by the fact that expression of different isoforms of human ApoE in transgenic mice results in different levels of plaque and CAA burden with apoE4 expression enhancing amyloid deposition compared to apoE3 or apoE2 [3, 21, 40, 59, 86, 178].”

    From Alzheimer's disease: experimental models and reality (2017) · cites this paper as [86]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • ApoE isoform comparison is described as both significant and nonsignificant

    Minor

    The results report a statistically significant difference in the fraction of Ab-positive CA2/3 neurons between ApoE2 and ApoE4 mice, but the discussion says no significant effect of human ApoE isoforms on the number of Ab-bearing neurons was observed.

1 of 1

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Related

Authors
Kuszczyk, M. A., Sanchez, S., Pankiewicz, J., Kim, J., Duszczyk, M., Guridi, M., Asuni, A. A., Sullivan, P. M., Holtzman, D. M., & Sadowski, M. J.
Affiliations
  • NYU Langone Health (US)
  • New York University (US)
  • Washington University in St. Louis (US)
  • Duke University (US)
Corresponding author
Sadowski, Martin J.
ORCID
Venue
The American Journal of Pathology
Publisher
Elsevier BV
Published
2013-05
Volume
182
Issue
5
Pages
1750-1768
ISSN
0002-9440 (ISSN-L)
DOI
10.1016/j.ajpath.2013.01.034
PMC
PMC3644726
OpenAlex
W1993523012
Semantic Scholar
ddf96075d9fd2cdf9e322b980f496a6b52066392
Cited by
89
References
59
Citations by year
2026: 3 · 2025: 10 · 2024: 6 · 2023: 4 · 2022: 13 · 2021: 6 · 2020: 9 · 2019: 7 · 2018: 5 · 2017: 2 · 2016: 3 · 2015: 5 · 2014: 10 · 2013: 6
FWCI
4.89
Type
journal article
Language
en
Open access
Licence
Locations
  • American Journal Of Pathology (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (submittedVersion)
  • PubMed Central (submittedVersion)
  • ePrints Soton (University of Southampton) (submittedVersion)
Funders
  • Yale University
  • National Institutes of Health (AG13956, R37 AG13956)
  • National Institute on Aging (R01 AG31221, K02 AG34176, P30AG008051, R37AG13956, R01AG031221, R37AG013956, K02AG034176)
Topics
  • Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
  • Life Sciences › Neuroscience › Neurology › Neuroinflammation and Neurodegeneration Mechanisms
  • Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
Keywords
apolipoprotein E, amyloid-beta, Alzheimer's disease, synaptic degeneration, amyloid oligomers, ApoE-deficient mice, APP/PS1 mice, synaptic proteins
MeSH terms
Animals, Apolipoproteins E, Astrocytes, Cells, Cultured, Endocytosis, Extracellular Space, Female, Hippocampus, Humans, Nerve Degeneration, Neurons, Protein Binding, Subcellular Fractions, Synapses, Amyloid beta-Peptides, Mice, Knockout, Coculture Techniques, Protein Isoforms, Mice, Gene Knockdown Techniques

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-17.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-17.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review