The R136S mutation in the APOE3 gene confers resilience against tau pathology via inhibition of the cGAS-STING-IFN pathway

Classified as probably not a substantial claim.

Tau pathology can interfere with neuronal circuits, resulting in theta and gamma oscillation deficits long before neurons die.

“Previous studies have shown that tau pathology can interfere with neuronal circuits, resulting in theta and gamma oscillation deficits long before neurons die16,20–23.”

• cites [16] Yoshiyama Y, Higuchi M, Zhang B, Huang SM, Iwata N, Saido TC, Maeda J, Suhara T, Trojanowski JQ, and Lee VM (2007). Synapse loss and microglial activation precede tangles in a P301S tauopathy mouse model. Neuron 53, 337– 351. 17270732 sourceNot checked — no full text of the source
• cites [20] Fu H, Rodriguez GA, Herman M, Emrani S, Nahmani E, Barrett G, Figueroa HY, Goldberg E, Hussaini SA, and Duff KE (2017). Tau Pathology Induces Excitatory Neuron Loss, Grid Cell Dysfunction, and Spatial Memory Deficits Reminiscent of Early Alzheimer’s Disease. Neuron 93, 533– 541 e535. 10.1016/j.neuron.2016.12.023. 28111080 PMC5363269 sourceDisputed

  The Results section (page unavailable) reports increased theta power in 30+-month-old EC-Tau mice, but no significant gamma-power difference in any group. The Discussion (page unavailable) links the theta increase to extensive neuronal loss, rather than showing theta and gamma deficits long before neurons die. (LLM, conf=0.88)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites [21] Busche MA, Wegmann S, Dujardin S, Commins C, Schiantarelli J, Klickstein N, Kamath TV, Carlson GA, Nelken I, and Hyman BT (2019). Tau impairs neural circuits, dominating amyloid-beta effects, in Alzheimer models in vivo. Nat Neurosci 22, 57– 64. 10.1038/s41593-018-0289-8. 30559471 PMC6560629 sourcePartly supported

  The Results section ('Aβ promotes neuronal hyperactivity while tau suppresses activity'; page unavailable) reports markedly reduced cortical neuronal activity in tau-model mice, supporting the claim that tau interferes with neural circuits. The paper measures neuronal calcium activity, not theta or gamma oscillations, and these passages do not establish that the deficits occur long before neuronal death. (LLM, conf=0.87)

  Experimental — accuracy not yet measured
• cites [22] Yuan P, Zhang M, Tong L, Morse TM, McDougal RA, Ding H, Chan D, Cai Y, and Grutzendler J (2022). PLD3 affects axonal spheroids and network defects in Alzheimer’s disease. Nature 612, 328– 337. 10.1038/s41586-022-05491-6. 36450991 PMC9729106 sourcePartly supported

  The Functional impact of axonal spheroids section (page unavailable) says plaque-associated axonal spheroids may affect neuronal circuits for extended periods without loss of the parent axon. The paper attributes this disruption to amyloid-associated spheroids, however, and the passages do not report tau pathology or theta and gamma oscillation deficits. (LLM, conf=0.82)

  Experimental — accuracy not yet measured
• cites [23] Nakamura A, Cuesta P, Fernandez A, Arahata Y, Iwata K, Kuratsubo I, Bundo M, Hattori H, Sakurai T, Fukuda K, (2018). Electromagnetic signatures of the preclinical and prodromal stages of Alzheimer’s disease. Brain 141, 1470– 1485. 10.1093/brain/awy044. 29522156 PMC5920328 sourcePartly supported

  The Results (General profile of the regional power spectra; page unavailable) report altered theta-band power in mild cognitive impairment, supporting only the broad point that oscillations change. The paper does not link those changes to tau pathology, report gamma deficits, or establish that they occur before neuronal death; its Results instead relate theta power to hippocampal grey-matter volume. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

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

Amyloid pathology induces abnormal theta and gamma oscillations, likely due to deficient inhibitory interneuron activity.

“Previous studies show that amyloid pathology induces abnormal theta and gamma oscillations, likely due to deficient inhibitory interneuron activity, not examined here20,49,50.”

• cites [20] Fu H, Rodriguez GA, Herman M, Emrani S, Nahmani E, Barrett G, Figueroa HY, Goldberg E, Hussaini SA, and Duff KE (2017). Tau Pathology Induces Excitatory Neuron Loss, Grid Cell Dysfunction, and Spatial Memory Deficits Reminiscent of Early Alzheimer’s Disease. Neuron 93, 533– 541 e535. 10.1016/j.neuron.2016.12.023. 28111080 PMC5363269 sourceDisputed

  The Results section on interneuron firing and oscillations reports increased interneuron firing and theta power in aged EC-Tau mice, but no significant difference in gamma power. The Discussion attributes the theta change to tau pathology and increased inhibitory activity, rather than amyloid pathology and deficient interneuron activity. No page number is available in our copy. (LLM, conf=0.89)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites [49] Busche MA, and Konnerth A (2015). Neuronal hyperactivity--A key defect in Alzheimer’s disease? Bioessays 37, 624– 632. 10.1002/bies.201500004. 25773221 sourceNot checked — no full text of the source
• cites [50] Verret L, Mann EO, Hang GB, Barth AM, Cobos I, Ho K, Devidze N, Masliah E, Kreitzer AC, Mody I, (2012). Inhibitory interneuron deficit links altered network activity and cognitive dysfunction in Alzheimer model. Cell 149, 708– 721. 10.1016/j.cell.2012.02.046. 22541439 PMC3375906 sourcePartly supported

  The Results section reports abnormal, reduced gamma activity in hAPPJ20 mice, and the Discussion links it to impaired inhibitory PV-cell function. The cited passages do not report abnormal theta oscillations; the findings also come from an amyloid-model mouse study rather than a direct demonstration that amyloid pathology induces both abnormalities. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

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

These critical regions for memory retention and retrieval are highly vulnerable to Aβ and tau pathology.

“These critical regions for memory retention and retrieval are highly vulnerable to Aβ and tau pathology25,26,27.”

• cites [25] Deng W, Aimone JB, and Gage FH (2010). New neurons and new memories: how does adult hippocampal neurogenesis affect learning and memory? Nat Rev Neurosci 11, 339– 350. 10.1038/nrn2822. 20354534 PMC2886712 sourcePartly supported

  The review’s section on computational models of adult-born dentate granule cell function discusses hippocampal memory retrieval, and its Conclusions and future directions section says Alzheimer’s disease affects human hippocampal neurogenesis. Neither passage says these regions are highly vulnerable to Aβ or tau pathology; searches for those terms found no supporting passage in our copy. Page numbers were unavailable. (LLM, conf=0.82)

  Experimental — accuracy not yet measured
• cites [26] Vago DR, Bevan A, and Kesner RP (2007). The role of the direct perforant path input to the CA1 subregion of the dorsal hippocampus in memory retention and retrieval. Hippocampus 17, 977– 987. 10.1002/hipo.20329. 17604347 PMC3057091 sourceNot checked — no full text of the source
• cites [27] Goettemoeller AM, Banks E, Kumar P, Olah VJ, McCann KE, South K, Ramelow CC, Eaton A, Duong DM, Seyfried NT, (2024). Entorhinal cortex vulnerability to human APP expression promotes hyperexcitability and tau pathology. Nat Commun 15, 7918. 10.1038/s41467-024-52297-3. 39256379 PMC11387477 sourcePartly supported

  The Introduction (page unavailable) identifies the lateral entorhinal cortex as an early site of Alzheimer’s pathology and reports amyloid pathology in its layer II neurons. The Results (page unavailable) also describe it as the first cortical region to develop tau pathology. The paper supports vulnerability of the entorhinal cortex, but these passages do not establish the claim for multiple memory-related regions or address their roles in memory retention and retrieval. (LLM, conf=0.83)

  Experimental — accuracy not yet measured

May combine two claims.

In mouse models on the risk-enhancing E4 background, the R136S mutation protected against tau pathology, neurodegeneration, and neuroinflammation.

“In mouse models on the risk-enhancing E4 background, the R136S mutation protected against tau pathology, neurodegeneration, and neuroinflammation14.”

• cites [14] Nelson MR, Liu P, Agrawal A, Yip O, Blumenfeld J, Traglia M, Kim MJ, Koutsodendris N, Rao A, Grone B, (2023). The APOE-R136S mutation protects against APOE4-driven Tau pathology, neurodegeneration and neuroinflammation. Nat Neurosci 26, 2104– 2121. 10.1038/s41593-023-01480-8. 37957317 PMC10689245 sourceSupported

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

E3 is the most common APOE variant and does not alter AD risk, while E4 elevates AD risk and E2 reduces AD risk.

“E3 is the most common APOE variant and does not alter AD risk, while E4 elevates AD risk and E2 reduces AD risk12,13.”

• cites [12] Arboleda-Velasquez JF, Lopera F, O’Hare M, Delgado-Tirado S, Marino C, Chmielewska N, Saez-Torres KL, Amarnani D, Schultz AP, Sperling RA, (2019). Resistance to autosomal dominant Alzheimer’s disease in an APOE3 Christchurch homozygote: a case report. Nat Med 25, 1680– 1683. 10.1038/s41591-019-0611-3. 31686034 PMC6898984 sourceSupported
• cites [13] Sepulveda-Falla D, Sanchez JS, Almeida MC, Boassa D, Acosta-Uribe J, Vila-Castelar C, Ramirez-Gomez L, Baena A, Aguillon D, Villalba-Moreno ND, (2022). Distinct tau neuropathology and cellular profiles of an APOE3 Christchurch homozygote protected against autosomal dominant Alzheimer’s dementia. Acta Neuropathol. 10.1007/s00401-022-02467-8. PMC9381462 35838824 sourcePartly supported

  The Introduction states that APOE4 is associated with increased risk of sporadic Alzheimer’s disease. It does not state that ordinary APOE3 is the most common variant or neutral for risk, or that APOE2 reduces risk. Its findings about protection concern the rare APOE3 Christchurch variant, not ordinary APOE3. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

May combine two claims.

E3S/S did not affect disease-associated microglial signatures (DAMs) or microglial neurodegenerative phenotype (MGnD).

“We performed snRNA-seq to identify cell type-specific transcriptomic changes, and discovered that E3S/S reduced cGAS-STING-IFN signaling in microglia without affecting disease-associated microglial signatures (DAMs)17 or microglial neurodegenerative phenotype (MGnD)18.”

• cites [17] Keren-Shaul H, Spinrad A, Weiner A, Matcovitch-Natan O, Dvir-Szternfeld R, Ulland TK, David E, Baruch K, Lara-Astaiso D, Toth B, (2017). A Unique Microglia Type Associated with Restricting Development of Alzheimer’s Disease. Cell 169, 1276– 1290 e1217. 10.1016/j.cell.2017.05.018. 28602351 sourceSupported
• cites [18] Krasemann S, Madore C, Cialic R, Baufeld C, Calcagno N, El Fatimy R, Beckers L, O’Loughlin E, Xu Y, Fanek Z, (2017). The TREM2-APOE Pathway Drives the Transcriptional Phenotype of Dysfunctional Microglia in Neurodegenerative Diseases. Immunity 47, 566– 581 e569. 10.1016/j.immuni.2017.08.008. 28930663 PMC5719893 sourceSupported

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

APOE is a lipid transporter expressed in astrocytes and microglia and affects microglial functions including neuroinflammation and phagocytosis.

“APOE is a lipid transporter expressed in astrocytes and microglia and has been shown to affect microglial functions including neuroinflammation and phagocytosis7–9.”

• cites [7] Lee S, Devanney NA, Golden LR, Smith CT, Schwartz JL, Walsh AE, Clarke HA, Goulding DS, Allenger EJ, Morillo-Segovia G, (2023). APOE modulates microglial immunometabolism in response to age, amyloid pathology, and inflammatory challenge. Cell Rep 42, 112196. 10.1016/j.celrep.2023.112196. 36871219 PMC10117631 sourcePartly supported

  The Results section on APOE expression reports that APOE is predominantly expressed by astrocytes and is also expressed by microglia. The Introduction and Discussion link APOE4 to heightened neuroinflammation and a pro-inflammatory microglial phenotype. The passages found do not show that APOE affects microglial phagocytosis, and they discuss lipid metabolism without explicitly identifying APOE as a lipid transporter. (LLM, conf=0.84)

  Experimental — accuracy not yet measured
• cites [8] Wang N, Wang M, Jeevaratnam S, Rosenberg C, Ikezu TC, Shue F, Doss SV, Alnobani A, Martens YA, Wren M, (2022). Opposing effects of apoE2 and apoE4 on microglial activation and lipid metabolism in response to demyelination. Mol Neurodegener 17, 75. 10.1186/s13024-022-00577-1. 36419137 PMC9682675 sourceSupported
• cites [9] Shi Y, Yamada K, Liddelow SA, Smith ST, Zhao L, Luo W, Tsai RM, Spina S, Grinberg LT, Rojas JC, (2017). ApoE4 markedly exacerbates tau-mediated neurodegeneration in a mouse model of tauopathy. Nature 549, 523– 527. 10.1038/nature24016. 28959956 PMC5641217Not checked yet

  Not checked in the free run.

May combine two claims.

The carrier exhibited low tau pathology in AD-vulnerable regions despite high amyloid burden, suggesting protective ability of the R136S mutation against tau-induced neurodegeneration.

“Despite high amyloid burden, the carrier exhibited low tau pathology in AD-vulnerable regions, frontal and occipital cortices13, suggesting protective ability of the R136S mutation against tau-induced neurodegeneration.”

• cites [13] Sepulveda-Falla D, Sanchez JS, Almeida MC, Boassa D, Acosta-Uribe J, Vila-Castelar C, Ramirez-Gomez L, Baena A, Aguillon D, Villalba-Moreno ND, (2022). Distinct tau neuropathology and cellular profiles of an APOE3 Christchurch homozygote protected against autosomal dominant Alzheimer’s dementia. Acta Neuropathol. 10.1007/s00401-022-02467-8. PMC9381462 35838824 sourcePartly supported

  The Results (Neuroimaging findings; page unavailable) report very high amyloid burden, and the Abstract reports frontal-cortex sparing and severe occipital-cortex tau pathology. The Discussion suggests the APOE3 Christchurch variant likely provided general protection against tau pathology, but specifically says it did not protect the occipital cortex. Thus, the claim’s description of low tau pathology in both cortices is not supported. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

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

Amyloid pathology typically develops first followed by tau pathology, which correlates with AD progression and cognitive impairment.

“Amyloid pathology typically develops first followed by tau pathology, which correlates with AD progression and cognitive impairment2–4.”

• cites [2] Malpetti M, Joie R, and Rabinovici GD (2022). Tau Beats Amyloid in Predicting Brain Atrophy in Alzheimer Disease: Implications for Prognosis and Clinical Trials. J Nucl Med 63, 830– 832. 10.2967/jnumed.121.263694. 35649659 PMC9157718 sourcePartly supported

  The paper’s discussion of amyloid and tau PET (page not provided) describes early amyloid accumulation and tau spreading in the presence of amyloid, but does not establish that amyloid pathology typically begins before tau pathology. It does state that increasing tau spread is associated with clinical impairment and that tau tangles are strongly associated with cognitive deficits. (LLM, conf=0.83)

  Experimental — accuracy not yet measured
• cites [3] Lee JC, Kim SJ, Hong S, and Kim Y (2019). Diagnosis of Alzheimer’s disease utilizing amyloid and tau as fluid biomarkers. Exp Mol Med 51, 1– 10. 10.1038/s12276-019-0250-2. PMC6509326 31073121 sourcePartly supported

  The Introduction (page unavailable) says amyloid plaques and tau tangles often parallel cognitive impairment, and the Cerebrospinal fluid section treats both as markers of AD progression. The paper does not establish the claimed typical sequence in which amyloid pathology develops before tau pathology. (LLM, conf=0.85)

  Experimental — accuracy not yet measured
• cites [4] Bloom GS (2014). Amyloid-beta and tau: the trigger and bullet in Alzheimer disease pathogenesis. JAMA Neurol 71, 505– 508. 10.1001/jamaneurol.2013.5847. 24493463 PMC12908160 sourcePartly supported

  The Abstract says Aβ is upstream of tau in AD pathogenesis and that behavioral symptoms correlate with the accumulation of plaques and tangles. The In Vivo Evidence section describes Aβ accelerating tangle deposition in mouse models. These passages support a mechanistic sequence and a link to cognitive symptoms, but they do not establish that amyloid pathology typically develops before tau pathology in people with AD or specifically correlate tau pathology with disease progression. (LLM, conf=0.83)

  Experimental — accuracy not yet measured

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

Tau-induced hyperexcitability exacerbates synaptic and cognitive decline in a model of amyloid toxicity.

“This aligns with evidence that tau-induced hyperexcitability exacerbates synaptic and cognitive decline in a model of amyloid toxicity56.”

• cites [56] Roberson ED, Halabisky B, Yoo JW, Yao J, Chin J, Yan F, Wu T, Hamto P, Devidze N, Yu GQ, (2011). Amyloid-beta/Fyn-induced synaptic, network, and cognitive impairments depend on tau levels in multiple mouse models of Alzheimer’s disease. J Neurosci 31, 700– 711. 31/2/700 [pii] 10.1523/JNEUROSCI.4152-10.2011 [doi]. 21228179 PMC3325794 sourcePartly supported

  The Abstract and Discussion report that tau reduction prevented synaptic deficits, epileptiform activity, and cognitive impairment in amyloid-β mouse models. The Discussion suggests aberrant network activity contributes to cognitive impairment, but it does not establish that tau-induced hyperexcitability itself exacerbates both synaptic and cognitive decline; tau is described as enabling effects of amyloid-β and Fyn. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

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

Other upregulated genes in astrocytes include Slc1a2, a glial high-affinity glutamate transporter.

“Other upregulated genes, including a glial high-affinity glutamate transporter (Slc1a2), play a role in synaptic clearance of glutamate, thereby preventing excitotoxicity34 (Fig. S4C, Table S1).”

• cites [34] Yang Y, Gozen O, Watkins A, Lorenzini I, Lepore A, Gao Y, Vidensky S, Brennan J, Poulsen D, Won Park J, (2009). Presynaptic regulation of astroglial excitatory neurotransmitter transporter GLT1. Neuron 61, 880– 894. 10.1016/j.neuron.2009.02.010. 19323997 PMC2743171 sourceSupported

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

Evidence that FTD tau pathology leads to similar network dysfunction suggests converging network dysfunction in AD and primary tauopathies.

“Evidence that FTD tau pathology leads to similar network dysfunction suggests converging network dysfunction in AD and primary tauopathies51–53.”

• cites [51] Hijazi S, Heistek TS, Scheltens P, Neumann U, Shimshek DR, Mansvelder HD, Smit AB, and van Kesteren RE (2020). Early restoration of parvalbumin interneuron activity prevents memory loss and network hyperexcitability in a mouse model of Alzheimer’s disease. Mol Psychiatry 25, 3380– 3398. 10.1038/s41380-019-0483-4. 31431685 PMC7714697 sourcePartly supported

  The Introduction describes neuronal network dysfunction in AD, and the Discussion reports early network alterations in APP/PS1 mice. The paper does not report that FTD tau pathology causes similar dysfunction or establish convergence between AD and primary tauopathies. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites [52] Algamal M, Russ AN, Miller MR, Hou SS, Maci M, Munting LP, Zhao Q, Gerashchenko D, Bacskai BJ, and Kastanenka KV (2022). Reduced excitatory neuron activity and interneuron-type-specific deficits in a mouse model of Alzheimer’s disease. Commun Biol 5, 1323. 10.1038/s42003-022-04268-x. 36460716 PMC9718858 sourcePartly supported

  The Discussion reports network dysfunction in an APP/PS1 mouse model of Alzheimer’s disease, including altered interneuron and excitatory-neuron activity. Our copy does not report evidence that FTD tau pathology causes similar dysfunction or establish convergence between AD and primary tauopathies; searches for FTD and tau-related circuit dysfunction did not find that comparison. (LLM, conf=0.85)

  Experimental — accuracy not yet measured
• cites [53] Xu Y, Zhao M, Han Y, and Zhang H (2020). GABAergic Inhibitory Interneuron Deficits in Alzheimer’s Disease: Implications for Treatment. Front Neurosci 14, 660. 10.3389/fnins.2020.00660. 32714136 PMC7344222 sourcePartly supported

  The ‘Targets to Improve GABA Inhibitory Interneuron Activity’ section reports abnormal neural network activity in TauP301L mice and describes excitation–inhibition imbalance during AD development (page not provided). This supports a similarity in network dysfunction, but the cited paper does not establish that FTD tau pathology causes it or directly compare AD with primary tauopathies. (LLM, conf=0.83)

  Experimental — accuracy not yet measured

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

RBM25 is downregulated in tangle-bearing AT8+ neurons in AD brains.

“These findings are consistent with previous studies showing that RBM25 is downregulated in tangle-bearing AT8+ neurons in AD brains35.”

• cites [35] Otero-Garcia M, Mahajani SU, Wakhloo D, Tang W, Xue YQ, Morabito S, Pan J, Oberhauser J, Madira AE, Shakouri T, (2022). Molecular signatures underlying neurofibrillary tangle susceptibility in Alzheimer’s disease. Neuron 110, 2929– 2948.e2928. 10.1016/j.neuron.2022.06.021. 35882228 PMC9509477 sourceCould not verify

  The Results sections compare AT8+ and AT8− neurons and report expression changes for several named genes, but the passages found do not mention RBM25. Searches for “RBM25” and “RNA-binding motif protein 25” found no passage establishing its downregulation in tangle-bearing neurons. (LLM, conf=0.73)

  Experimental — accuracy not yet measured

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

Gamma frequency modulation was beneficial in models with amyloid and/or tau pathology.

“Indeed, gamma frequency modulation was beneficial in models with amyloid and/or tau pathology54.”

• cites [54] Iaccarino HF, Singer AC, Martorell AJ, Rudenko A, Gao F, Gillingham TZ, Mathys H, Seo J, Kritskiy O, Abdurrob F, (2016). Gamma frequency entrainment attenuates amyloid load and modifies microglia. Nature 540, 230– 235. 10.1038/nature20587. 27929004 PMC5656389 sourceSupported

May combine two claims.

AD patients exhibit myelin loss, and higher myelin expression is associated with tau pathology protection in AD.

“AD patients exhibit myelin loss, and higher myelin expression is associated with tau pathology protection in AD43,44.”

• cites [43] McQuade A, Coburn M, Tu CH, Hasselmann J, Davtyan H, and Blurton-Jones M (2018). Development and validation of a simplified method to generate human microglia from pluripotent stem cells. Mol Neurodegener 13, 67. 10.1186/s13024-018-0297-x. 30577865 PMC6303871 sourceCould not verify

  The Background and Discussion discuss microglia in Alzheimer’s disease, while the Results examine stem-cell-derived microglia. Searches for myelin loss, myelin expression, and tau pathology found no passage addressing either part of the claim; no page numbers are available in our copy. (LLM, conf=0.76)

  Experimental — accuracy not yet measured
• cites [44] Lama L, Adura C, Xie W, Tomita D, Kamei T, Kuryavyi V, Gogakos T, Steinberg JI, Miller M, Ramos-Espiritu L, (2019). Development of human cGAS-specific small-molecule inhibitors for repression of dsDNA-triggered interferon expression. Nat Commun 10, 2261. 10.1038/s41467-019-08620-4. 31113940 PMC6529454 sourceCould not verify

  The Introduction discusses cGAS-mediated inflammatory responses, and the Methods examine interferon-related expression in macrophages; neither addresses myelin loss or tau pathology in Alzheimer’s disease. Searches of our full-text copy for myelin, tau, and AD patients found no passage supporting either part of the claim. (LLM, conf=0.78)

  Experimental — accuracy not yet measured

Classified as probably not a substantial claim.

EAAT2 agonism is neuroprotective.

“Because EAAT2 agonism is neuroprotective62, dissecting how R136S enhances EAAT2 expression may be therapeutic.”

• cites [62] Kong Q, Chang LC, Takahashi K, Liu Q, Schulte DA, Lai L, Ibabao B, Lin Y, Stouffer N, Das Mukhopadhyay C, (2014). Small-molecule activator of glutamate transporter EAAT2 translation provides neuroprotection. J Clin Invest 124, 1255– 1267. 10.1172/JCI66163. 24569372 PMC3938250 sourceSupported

Classified as probably not a substantial claim.

Maladaptive microglia are central in pathological tau spread and toxicity.

“Maladaptive microglia are central in pathological tau spread and toxicity40,47.”

• cites [40] Wang C, Fan L, Khawaja RR, Liu B, Zhan L, Kodama L, Chin M, Li Y, Le D, Zhou Y, (2022). Microglial NF-κB drives tau spreading and toxicity in a mouse model of tauopathy. Nat Commun 13, 1969. 10.1038/s41467-022-29552-6. 35413950 PMC9005658 sourceSupported
• cites [47] Asai H, Ikezu S, Tsunoda S, Medalla M, Luebke J, Haydar T, Wolozin B, Butovsky O, Kugler S, and Ikezu T (2015). Depletion of microglia and inhibition of exosome synthesis halt tau propagation. Nat Neurosci 18, 1584– 1593. 10.1038/nn.4132. 26436904 PMC4694577 sourceSupported

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

APOE4 has been linked to demyelination, even without tau pathology.

“Notably, APOE4 has also been linked to demyelination, even without tau pathology45.”

• cites [45] Lopez-Lee C, Kodama L, Fan L, Zhu D, Zhu J, Wong MY, Ye P, Norman K, Foxe NR, Ijaz L, (2024). Tlr7 drives sex differences in age- and Alzheimer’s disease-related demyelination. Science 386, eadk7844. 10.1126/science.adk7844. 39607927 PMC12396121 sourceSupported

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

These gangliosides are known to form toxic aggregates commonly associated with neurodegenerative diseases including FTD and Gaucher's disease.

“These gangliosides are known to form toxic aggregates commonly associated with neurodegenerative diseases including FTD38 and Gaucher’s disease63.”

• cites [38] Boland S, Swarup S, Ambaw YA, Malia PC, Richards RC, Fischer AW, Singh S, Aggarwal G, Spina S, Nana AL, (2022). Deficiency of the frontotemporal dementia gene GRN results in gangliosidosis. Nat Commun 13, 5924. 10.1038/s41467-022-33500-9. 36207292 PMC9546883 sourcePartly supported

  The Results section reports increased ganglioside levels in the frontal lobes of patients with GRN-associated FTD. It does not say gangliosides form toxic aggregates; the Discussion refers instead to possible downstream aggregation of proteins. Gaucher’s disease is attached to a different citation in the citing sentence, so it is not assessed here. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites [63] Blumenreich S, Nehushtan T, Barav OB, Saville JT, Dingjan T, Hardy J, Fuller M, and Futerman AH (2022). Elevation of gangliosides in four brain regions from Parkinson’s disease patients with a GBA mutation. NPJ Parkinsons Dis 8, 99. 10.1038/s41531-022-00363-2. 35933559 PMC9357011 sourcePartly supported

  The Discussion (page not provided) says exosomes containing gangliosides may accelerate α-synuclein aggregation and reports elevated gangliosides in Parkinson’s patients with a GBA mutation. It does not say that gangliosides themselves form toxic aggregates, or establish that such aggregates are associated with Gaucher’s disease. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

May combine two claims.

APOE4 exacerbates tau-induced neurodegeneration, partially attributed to a critical immune hub that involves IFN-driven microglial activation and interaction with cytotoxic T cells.

“Moreover, APOE4 exacerbates tau-induced neurodegeneration, partially attributed to a critical immune hub that involves IFN-driven microglial activation and interaction with cytotoxic T cells64,65.”

• cites [64] Shi Y, Yamada K, Liddelow SA, Smith ST, Zhao L, Luo W, Tsai RM, Spina S, Grinberg LT, Rojas JC, (2017). ApoE4 markedly exacerbates tau-mediated neurodegeneration in a mouse model of tauopathy. Nature 549, 523– 527. 10.1038/nature24016. 28959956 PMC5641217Not checked yet

  Not checked in the free run.

• cites [65] Chen X, Firulyova M, Manis M, Herz J, Smirnov I, Aladyeva E, Wang C, Bao X, Finn MB, Hu H, (2023). Microglia-mediated T cell infiltration drives neurodegeneration in tauopathy. Nature 615, 668– 677. 10.1038/s41586-023-05788-0. 36890231 PMC10258627 sourcePartly supported

  The paper reports somewhat greater brain atrophy in tauopathy mice expressing APOE4 than in those expressing APOE3, and its ‘Interaction of microglia and T cells’ section links tauopathy to interferon-activated microglia and T-cell infiltration. But the ‘Increased T cells with tau pathology’ section says T-cell increases also occur with APOE3 and mouse ApoE; the paper does not establish that this immune hub specifically explains APOE4’s additional effect. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

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

Marino et al. developed an APOE3 Christchurch-inspired antibody to disrupt APOE4-HSPG interactions, resulting in reduced tau pathology in P301S mouse retinas and brains.

“Marino et al. developed an APOE3 Christchurch-inspired antibody to disrupt APOE4-HSPG interactions, resulting in reduced tau pathology in P301S mouse retinas and brains66.”

• cites [66] Marino C, Perez-Corredor P, O’Hare M, Heuer A, Chmielewska N, Gordon H, Chandrahas AS, Gonzalez-Buendia L, Delgado-Tirado S, Doan TH, (2024). APOE Christchurch-mimetic therapeutic antibody reduces APOE-mediated toxicity and tau phosphorylation. Alzheimers Dement 20, 819– 836. 10.1002/alz.13436. 37791598 PMC10916992 sourcePartly supported

  The Results report that the Christchurch-mimetic 7C11 antibody reduced ApoE3-induced tau pathology in P301S mouse retinas. They also report reduced brain tau phosphorylation, but that experiment used APOE4 knock-in mice, not P301S mice (Results, Figures 4–5; page numbers unavailable). (LLM, conf=0.92)

  Experimental — accuracy not yet measured

May combine two claims.

Cgas deletion mitigated tau-induced microglial IFN-I and protected against synapse loss, decreased synaptic plasticity, and cognitive deficits.

“Cgas deletion mitigated tau-induced microglial IFN-I and protected against synapse loss, decreased synaptic plasticity, and cognitive deficits41.”

• cites [41] Udeochu JC, Amin S, Huang Y, Fan L, Torres ERS, Carling GK, Liu B, McGurran H, Coronas-Samano G, Kauwe G, (2023). Tau activation of microglial cGAS-IFN reduces MEF2C-mediated cognitive resilience. Nat Neurosci 26, 737– 750. 10.1038/s41593-023-01315-6. 37095396 PMC10166855 sourceSupported

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

Neurogenesis is known to be elevated following hyperexcitability.

“Among the downregulated pathways in E3S/S/P301S hippocampus, neurogenesis is known to be elevated following hyperexcitability58,59, observed in E3/P301S mice using cFOS activity mapping.”

• cites [58] Li G, Bien-Ly N, Andrews-Zwilling Y, Xu Q, Bernardo A, Ring K, Halabisky B, Deng C, Mahley RW, and Huang Y (2009). GABAergic interneuron dysfunction impairs hippocampal neurogenesis in adult apolipoprotein E4 knockin mice. Cell Stem Cell 5, 634– 645. 10.1016/j.stem.2009.10.015. 19951691 PMC2992822 sourcePartly supported

  The Results section on GABAA receptor manipulation reports increased newborn-cell proliferation when GABA signaling was inhibited. But the Results section on GABAergic interneurons describes impaired neuronal maturation in that setting, and the paper does not establish that hyperexcitability elevates overall neurogenesis. Page numbers are unavailable in our copy. (LLM, conf=0.82)

  Experimental — accuracy not yet measured
• cites [59] Pineda JR, and Encinas JM (2016). The Contradictory Effects of Neuronal Hyperexcitation on Adult Hippocampal Neurogenesis. Front Neurosci 10, 74. 10.3389/fnins.2016.00074. 26973452 PMC4776215 sourcePartly supported

  The Introduction (page not provided) reports an early increase in cell proliferation after seizures and increased stem-cell activation after electroconvulsive shock. But “Activation and exhaustion of NSCs” says that, in the following weeks after seizures, neurogenesis diminishes to a minimum. The unqualified claim that neurogenesis is elevated following hyperexcitability omits this time-dependent reversal. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

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

Previous findings showed that R136S mutation enhances microglial response around amyloid plaques on E3 background, but downregulates disease-associated gene profiles on E4 background.

“Previous findings showed that R136S mutation enhances microglial response around amyloid plaques on E3 background15, but downregulates disease-associated gene profiles on E4 background14.”

• cites [15] Chen Y, Song S, Parhizkar S, Lord J, Zhu Y, Strickland MR, Wang C, Park J, Tabor GT, Jiang H, (2023). APOE3ch alters microglial response and suppresses Abeta-induced tau seeding and spread. Cell. 10.1016/j.cell.2023.11.029. PMC10842861 38086389 sourceNot checked — no full text of the source
• cites [14] Nelson MR, Liu P, Agrawal A, Yip O, Blumenfeld J, Traglia M, Kim MJ, Koutsodendris N, Rao A, Grone B, (2023). The APOE-R136S mutation protects against APOE4-driven Tau pathology, neurodegeneration and neuroinflammation. Nat Neurosci 26, 2104– 2121. 10.1038/s41593-023-01480-8. 37957317 PMC10689245 sourceSupported

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

In macrophages, HSPGs modulate inflammation through interferon-beta (IFN-β) via IFN-β sequestration, enabling proteoglycan sulfation to influence inflammatory responses.

“In macrophages, HSPGs modulate inflammation through interferon-beta (IFN-β) via IFN-β sequestration, enabling proteoglycan sulfation to influence inflammatory responses67.”

• cites [67] Gordts P, Foley EM, Lawrence R, Sinha R, Lameda-Diaz C, Deng L, Nock R, Glass CK, Erbilgin A, Lusis AJ, (2014). Reducing macrophage proteoglycan sulfation increases atherosclerosis and obesity through enhanced type I interferon signaling. Cell Metab 20, 813– 826. 10.1016/j.cmet.2014.09.016. 25440058 PMC4254584 sourceSupported

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

E3S/S led to a modest increase in frontal cortex APOE expression in females.

“However, E3S/Sled to a modest increase in frontal cortex APOE expression in females (Fig. S1E–F).”

May combine two claims.

Tauopathy increased c-Fos-based brain activity on the E3 background, but this was reversed on the E3S/S background.

“Tauopathy increased c-Fos-based brain activity on the E3 background, but this was reversed on the E3S/S background (Fig. S2B–C).”

May combine two claims.

Subcluster 2 (OL2) was reduced by tau in E3 but preserved in E3S/S oligodendrocytes.

“Subcluster 2 (OL2) was reduced by tau in E3 but preserved in E3S/Soligodendrocytes (Fig. 3C–D, Table S2).”

May combine two claims.

Top inhibited upstream regulators in E3S/S/P301S microglia included cGAS and IFNA, and top activated upstream regulators included TREX1 and RNASEH2B.

“Indeed, top inhibited upstream regulators in E3S/S/P301S microglia included antiviral activators as cGAS and IFNA, and top activated upstream regulators included antiviral suppressors TREX1 and RNASEH2B (Fig. 4L, Table S3).”

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

MG2 strongly correlated with DAM markers.

“MG2 strongly correlated with DAM markers (Fig. 4H).”

May combine two claims.

Tau treatment substantially increased pSTING and pTBK1 expression in E3 iMGLs, but activation was abolished in E3S/S iMGLs.

“Immunocytochemistry showed that tau treatment substantially increased pSTING and pTBK1 expression in E3 iMGLs, but activation was abolished in E3S/S iMGLs, indicating that R136S suppressed tau-induced activation of the cGAS-STING-IFN pathway (Fig. 6G–J).”

The quote only partly states this claim.

The R136S mutation downregulated Them4 in astrocytes.

“Transcriptomic analyses revealed that the R136S mutation downregulated Thioesterase Superfamily Member 4 (Them4), which modulates mitochondrial fatty acid metabolism and is involved in apoptosis (Fig. S4C, Table S1).”

May combine two claims.

E3/P301S microglia demonstrated a robust type I interferon response to tau, which was markedly blunted in E3S/S/P301S counterparts.

“Indeed, E3/P301S microglia demonstrated a robust type I interferon response to tau, which was markedly blunted in E3S/S/P301S counterparts (Fig 4K, Table S1).”

May combine two claims.

Upregulated genes in ENs were involved in regulation of membrane potential, inorganic ion transmembrane transport, and RNA processing.

“Using gene set enrichment analysis (GSEA), we found that upregulated genes in ENs also were involved in regulation of membrane potential, inorganic ion transmembrane transport, and RNA processing (Pnn, Pnisr) (Fig. S4E).”

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

Another top downregulated gene in astrocytes was Grm5.

“Another top downregulated gene in astrocytes was metabotropic glutamate receptor 5 (Grm5) (Fig. S4C, Table S1).”

May combine two claims.

Comparing top 50 DEGs between E3S/S/P301S and E3/P301S across excitatory and inhibitory neurons showed that splicing-related genes were shared and predominantly upregulated in both cell types.

“Comparing the top 50 DEGs between E3S/S/P301S and E3/P301S across excitatory and inhibitory neurons showed that splicing-related genes were shared and predominantly upregulated in both cell types (Fig. S4H, Table S1).”

May combine two claims.

Aβ-treated E3S/S microglia downregulated interferon genes, with IFN signaling, cytokine signaling, and innate immune response among top downregulated pathways.

“Similarly, Aβ-treated E3S/S microglia downregulated interferon genes (Ifi211, Ifi204, Cxcl13, Ifi47), with IFN signaling, cytokine signaling, and innate immune response among the top downregulated pathways (Fig. 5F–G, Fig. S5E, Table S4).”

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

Aβ-treated E3S/S microglia upregulated Rho-GTPases and collagen synthesis pathways.

“while Aβ-treated E3S/S microglia upregulated Rho-GTPases and collagen synthesis pathways (Fig. S5G, Table S4).”

May combine two claims.

Microglia in E3/P301S and E3S/S/P301S mice exhibited similar loss of MG1 and similar induction of MG2.

“SnRNA-seq revealed that microglia in E3/P301S and E3S/S/P301S mice exhibited similar loss of microglial subcluster 1 (MG1), enriched in homeostatic markers, and similar induction of subcluster 2 (MG2) (Fig. 4F–G, Table S3).”

May combine two claims.

Tau increased soma volume in E3/P301S microglia, while E3S/S prevented this increase.

“Using IMARIS 3D reconstruction of microglial morphology, we found that tau increased soma volume in E3/P301S microglia, while the E3S/S mutation prevented this increase (Fig. 4C–D).”

May combine two claims.

Among RNA-splicing factors, RBM25 is downregulated in E3 tauopathy neurons, but rescued by R136S.

“Among RNA-splicing factors, RBM25 is downregulated in E3 tauopathy neurons, but rescued by R136S.”

May combine two claims.

cGASi administration corrected transcriptomes across cell types and protected synapses.

“Secondly, while cGASi administration corrected transcriptomes across cell types and protected synapses, whether cGAS inhibition rescues circuit dysfunction or alterations in neuronal splicing factors remains unknown.”

May combine two claims.

The resilient E3S/S allele suppresses tau-induced cGAS-STING-IFN signaling in microglia while maintaining DAM responses, protectively balancing immune activation and resilience pathways.

“Our current findings reveal that the resilient E3S/S allele suppresses tau-induced cGAS-STING-IFN signaling in microglia while maintaining DAM responses, protectively balancing immune activation and resilience pathways.”

May combine two claims.

The R136S mutation alters oligodendrocyte transcriptomes and protects against tau-induced myelin loss.

“Our findings suggest that the R136S mutation alters oligodendrocyte transcriptomes and protects against tau-induced myelin loss.”

Classified as probably not a substantial claim.

c-Fos expression is a well-established indicator of mouse brain activity.

“Expression of c-Fos, an immediate early-gene marker, is a well-established indicator of mouse brain activity24.”

• cites [24] Bullitt E (1990). Expression of c-fos-like protein as a marker for neuronal activity following noxious stimulation in the rat. J Comp Neurol 296, 517– 530. 10.1002/cne.902960402. 2113539 sourceNot checked — no full text of the source

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

88,605 nuclei passed stringent quality control (QC).

“88,605 nuclei passed stringent quality control (QC) (Fig. S3).”

Classified as probably not a substantial claim.

Sanger sequencing confirmed the replacement accuracy.

“Sanger sequencing was performed to confirm the replacement accuracy (Fig. S1 B, C).”

May combine two claims.

cGAS inhibition reduced tau spread and treatment after disease onset recapitulated key aspects of R136S-mediated resilience to tau toxicity, including transcriptomic profiles in neurons and microglia and preservation of synaptic integrity.

“In summary, cGAS inhibition reduced tau spread, and treatment after disease onset recapitulated key aspects of R136S -mediated resilience to tau toxicity, including transcriptomic profiles in neurons and microglia and preservation of synaptic integrity.”

May combine two claims.

The R136S mutation enhances tau uptake and processing while dampening downstream cGAS-STING-IFN activation in mouse and human microglia.

“In summary, the R136S mutation enhances tau uptake and processing while dampening downstream cGAS-STING-IFN activation in mouse and human microglia.”

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

Experimenters performing imaging and quantification were blinded.

“Experimenters performing imaging and quantification were blinded.”

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

Multiple testing was controlled using the Benjamini-Hochberg approach to constrain the false discovery rate.

“To control for multiple testing, we used the Benjamini–Hochberg approach to constrain the FDR.”

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

Ganglioside quantification was achieved by normalizing the area under the curve to GM3-d5 standards and further normalizing to the amount of protein used in preparation.

“Quantification was achieved by normalizing the area under the curve to GM3-d5 standards, followed by further normalization to the amount of protein used in the preparation.”

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

Ceramides' role here may be context-dependent, potentially contributing to neuroprotection.

“While ceramides are typically linked to neurodegeneration, their role here may be context-dependent, potentially contributing to neuroprotection.”

May combine two claims.

The R136S mutation may confer cGAS-independent protection or earlier intervention is required.

“cGAS inhibition, however, did not prevent myelin loss, indicating the R136S mutation may confer cGAS-independent protection or that earlier intervention is required.”

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

EAAT2 expression diminishes with age and correlates with signs of neuronal death in postmortem brains of sporadic AD patients.

“EAAT2 expression diminishes with age60 and correlates with signs of neuronal death in postmortem brains of sporadic AD patients61.”

• cites [60] Sharma A, Kazim SF, Larson CS, Ramakrishnan A, Gray JD, McEwen BS, Rosenberg PA, Shen L, and Pereira AC (2019). Divergent roles of astrocytic versus neuronal EAAT2 deficiency on cognition and overlap with aging and Alzheimer’s molecular signatures. Proc Natl Acad Sci U S A 116, 21800– 21811. 10.1073/pnas.1903566116. 31591195 PMC6815169 sourceNot checked — no full text of the source
• cites [61] Masliah E, Alford M, DeTeresa R, Mallory M, and Hansen L (1996). Deficient glutamate transport is associated with neurodegeneration in Alzheimer’s disease. Ann Neurol 40, 759– 766. 10.1002/ana.410400512. 8957017 sourceNot checked — no full text of the source

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

Our results were obtained from full-body knockin models, limiting our ability to attribute the observed effects to microglial-derived APOE3S/S in vivo.

“Our results were obtained from full-body knockin models, limiting our ability to attribute the observed effects to microglial-derived APOE3S/S in vivo.”

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

Internal calibration was achieved using EASY-IC.

“with EASYICTM used for internal calibration”

• Also stated in: § METHOD DETAILS · plain

  “Internal calibration was achieved using EASY-IC™.”

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

The downregulation of cFOS activity by the R136S mutation could explain downregulated neurogenesis in the EN transcriptome.

“The downregulation of cFOS activity by the R136S mutation could explain downregulated neurogenesis in the EN transcriptome.”

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

Total RNA integrity was checked using a 2100 Bioanalyzer.

“total RNA integrity was checked using a 2100 Bioanalyzer (Agilent Technologies)”

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

SPLAH internal standards were added before lipid extraction.

“SPLAH internal standards were added before extraction.”

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

This study elucidates the impact of the R136S mutation on tau-induced network activity and function, reveals extensive transcriptomic effects on neurons and glial cells, and identifies a potential therapeutic pathway.

“Collectively, this study elucidates the impact of the R136S mutation on tau-induced network activity and function, reveals extensive transcriptomic effects on neurons and glial cells, and identifies a potential therapeutic pathway.”

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

All experimental procedures were approved by the Weill Cornell Medical College Animal Care and Use Committee following National Institutes of Health guideline.

“All experimental procedures were approved by the Weill Cornell Medical College Animal Care and Use Committee following National Institutes of Health guideline.”

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

To control for multiple testing, the Benjamini-Hochberg approach was used to constrain the FDR.

“To control for multiple testing, we used the Benjamini–Hochberg approach to constrain the FDR.”

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

Improved lysosomal function could mitigate tau-induced toxicity.

“Conversely, the reduction in gangliosides, such as GD1a and GQ1b, suggests improved lysosomal function38, which could mitigate tau-induced toxicity.”

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

All mouse protocols were approved by the Institutional Animal Care and Use Committee at Weill Cornell Medicine.

“All mouse protocols were approved by the Institutional Animal Care and Use Committee at Weill Cornell Medicine.”

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

Semi-targeted lipid quantification was performed by normalizing the area under the curve to internal standards and further normalizing to total quantified protein.

“Semi-targeted quantification was performed by normalizing the area under the curve (AUC) to the AUC of internal standards and further normalized with the total quantified protein.”