Rapamycin rescues vascular, metabolic and learning deficits in apolipoprotein E4 transgenic mice with pre-symptomatic Alzheimer’s disease

Apolipoprotein E ɛ4 allele is a common susceptibility gene for late-onset Alzheimer's disease. Brain vascular and metabolic deficits can occur in cognitively normal apolipoprotein E ɛ4 carriers decades before the onset of Alzheimer's disease. The goal of this study was to determine whether early intervention using rapamycin could restore neurovascular and neurometabolic functions, and thus impede pathological progression of Alzheimer's disease-like symptoms in pre-symptomatic Apolipoprotein E ɛ4 transgenic mice. Using in vivo, multimodal neuroimaging, we found that apolipoprotein E ɛ4 mice treated with rapamycin had restored cerebral blood flow, blood–brain barrier integrity and glucose metabolism, compared to age- and gender-matched wild-type controls. The preserved vasculature and metabolism were associated with amelioration of incipient learning deficits. We also found that rapamycin restored the levels of the proinflammatory cyclophilin A in vasculature, which may contribute to the preservation of cerebrovascular function in the apolipoprotein E ɛ4 transgenics. Our results show that rapamycin improves functional outcomes in this mouse model and may have potential as an effective intervention to block progression of vascular, metabolic and early cognitive deficits in human Apolipoprotein E ɛ4 carriers. As rapamycin is FDA-approved and neuroimaging is readily used in humans, the results of the present study may provide the basis for future Alzheimer's disease intervention studies in human subjects.

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Association between methylation of BIN1 promoter in peripheral blood and preclinical Alzheimer’s disease

Translational Psychiatry ◽

10.1038/s41398-021-01218-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hao Hu ◽

Lan Tan ◽

Yan-Lin Bi ◽

Wei Xu ◽

Lin Tan ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Peripheral Blood ◽

Late Onset ◽

Early Stage ◽

Susceptibility Gene ◽

Subjective Cognitive Decline ◽

Preclinical Ad ◽

T Tau ◽

New Evidence

AbstractThe bridging integrator 1 (BIN1) gene is the second most important susceptibility gene for late-onset Alzheimer’s disease (LOAD) after apolipoprotein E (APOE) gene. To explore whether the BIN1 methylation in peripheral blood changed in the early stage of LOAD, we included 814 participants (484 cognitively normal participants [CN] and 330 participants with subjective cognitive decline [SCD]) from the Chinese Alzheimer’s Biomarker and LifestylE (CABLE) database. Then we tested associations of methylation of BIN1 promoter in peripheral blood with the susceptibility for preclinical AD or early changes of cerebrospinal fluid (CSF) AD-related biomarkers. Results showed that SCD participants with significant AD biological characteristics had lower methylation levels of BIN1 promoter, even after correcting for covariates. Hypomethylation of BIN1 promoter were associated with decreased CSF Aβ42 (p = 0.0008), as well as increased p-tau/Aβ42 (p = 0.0001) and t-tau/Aβ42 (p < 0.0001) in total participants. Subgroup analysis showed that the above associations only remained in the SCD subgroup. In addition, hypomethylation of BIN1 promoter was also accompanied by increased CSF p-tau (p = 0.0028) and t-tau (p = 0.0130) in the SCD subgroup, which was independent of CSF Aβ42. Finally, above associations were still significant after correcting single nucleotide polymorphic sites (SNPs) and interaction of APOE ɛ4 status. Our study is the first to find a robust association between hypomethylation of BIN1 promoter in peripheral blood and preclinical AD. This provides new evidence for the involvement of BIN1 in AD, and may contribute to the discovery of new therapeutic targets for AD.

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Apolipoprotein E alleles but neither apolipoprotein B nor apolipoprotein AI/CIII alleles are associated with late onset, familial Alzheimer's disease

Neuroscience Letters ◽

10.1016/0304-3940(95)11422-s ◽

1995 ◽

Vol 188 (3) ◽

pp. 202-204 ◽

Cited By ~ 9

Author(s):

Henry Houlden ◽

Richard Crook ◽

Karen Duff ◽

Mike Hutton ◽

John Collinge ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Apolipoprotein E ◽

Apolipoprotein B ◽

Late Onset ◽

Apolipoprotein Ai ◽

Familial Alzheimer’S Disease ◽

Familial Alzheimer's Disease

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The clinical utility of gene testing for Alzheimer’s disease

Neurology International ◽

10.4081/ni.2011.e1 ◽

2011 ◽

Vol 3 (1) ◽

pp. 1 ◽

Cited By ~ 8

Author(s):

Emily R. Atkins ◽

Peter K. Panegyres

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Early Onset ◽

Late Onset ◽

Association Studies ◽

Susceptibility Gene ◽

Genome Wide Association Studies ◽

Apoe Ε4 ◽

Gene Testing ◽

A Genome

Alzheimer’s disease (AD) is the largest cause of dementia, affecting 35.6 million people in 2010. Amyloid precursor protein, presenilin 1 and presenilin 2 mutations are known to cause familial early-onset AD, whereas apolipoprotein E (APOE) ε4 is a susceptibility gene for late-onset AD. The genes for phosphatidylinositol- binding clathrin assembly protein, clusterin and complement receptor 1 have recently been described by genome-wide association studies as potential risk factors for lateonset AD. Also, a genome association study using single neucleotide polymorphisms has identified an association of neuronal sortilin related receptor and late-onset AD. Gene testing, and also predictive gene testing, may be of benefit in suspected familial early-onset AD however it adds little to the diagnosis of lateonset AD and does not alter the treatment. We do not recommend APOE ε4 genotyping.

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Gga3 deletion and a GGA3 rare variant associated with late onset Alzheimer’s disease trigger BACE1 accumulation in axonal swellings

Science Translational Medicine ◽

10.1126/scitranslmed.aba1871 ◽

2020 ◽

Vol 12 (570) ◽

pp. eaba1871

Author(s):

Selene Lomoio ◽

Rachel Willen ◽

WonHee Kim ◽

Kevin Z. Ho ◽

Edward K. Robinson ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Rare Variant ◽

Late Onset ◽

Early Stage ◽

Loss Of Function ◽

Axonal Trafficking ◽

Axonal Swellings

Axonal dystrophy, indicative of perturbed axonal transport, occurs early during Alzheimer’s disease (AD) pathogenesis. Little is known about the mechanisms underlying this initial sign of the pathology. This study proves that Golgi-localized γ-ear-containing ARF binding protein 3 (GGA3) loss of function, due to Gga3 genetic deletion or a GGA3 rare variant that cosegregates with late-onset AD, disrupts the axonal trafficking of the β-site APP-cleaving enzyme 1 (BACE1) resulting in its accumulation in axonal swellings in cultured neurons and in vivo. We show that BACE pharmacological inhibition ameliorates BACE1 axonal trafficking and diminishes axonal dystrophies in Gga3 null neurons in vitro and in vivo. These data indicate that axonal accumulation of BACE1 engendered by GGA3 loss of function results in local toxicity leading to axonopathy. Gga3 deletion exacerbates axonal dystrophies in a mouse model of AD before β-amyloid (Aβ) deposition. Our study strongly supports a role for GGA3 in AD pathogenesis, where GGA3 loss of function triggers BACE1 axonal accumulation independently of extracellular Aβ, and initiates a cascade of events leading to the axonal damage distinctive of the early stage of AD.

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Elevated Aβ and Apolipoprotein E in AβPP Transgenic Mice and Its Relationship to Amyloid Accumulation in Alzheimer’s Disease

Molecular Medicine ◽

10.1007/bf03401785 ◽

2000 ◽

Vol 6 (5) ◽

pp. 430-439 ◽

Cited By ~ 47

Author(s):

Yu-Min Kuo ◽

Fiona Crawford ◽

Michael Mullan ◽

Tyler A. Kokjohn ◽

Mark R. Emmerling ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Transgenic Mice ◽

Apolipoprotein E ◽

Amyloid Accumulation

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N,N′-Diacetyl-p-phenylenediamine restores microglial phagocytosis and improves cognitive defects in Alzheimer’s disease transgenic mice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1916318116 ◽

2019 ◽

Vol 116 (47) ◽

pp. 23426-23436 ◽

Cited By ~ 6

Author(s):

Min Hee Park ◽

Misun Lee ◽

Geewoo Nam ◽

Mingeun Kim ◽

Juhye Kang ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Transgenic Mice ◽

Amyloid Β ◽

Causative Factor ◽

Central Feature ◽

Microglial Phagocytosis ◽

Cognitive Defects

As a central feature of neuroinflammation, microglial dysfunction has been increasingly considered a causative factor of neurodegeneration implicating an intertwined pathology with amyloidogenic proteins. Herein, we report the smallest synthetic molecule (N,N′-diacetyl-p-phenylenediamine [DAPPD]), simply composed of a benzene ring with 2 acetamide groups at the para position, known to date as a chemical reagent that is able to promote the phagocytic aptitude of microglia and subsequently ameliorate cognitive defects. Based on our mechanistic investigations in vitro and in vivo, 1) the capability of DAPPD to restore microglial phagocytosis is responsible for diminishing the accumulation of amyloid-β (Aβ) species and significantly improving cognitive function in the brains of 2 types of Alzheimer’s disease (AD) transgenic mice, and 2) the rectification of microglial function by DAPPD is a result of its ability to suppress the expression of NLRP3 inflammasome-associated proteins through its impact on the NF-κB pathway. Overall, our in vitro and in vivo investigations on efficacies and molecular-level mechanisms demonstrate the ability of DAPPD to regulate microglial function, suppress neuroinflammation, foster cerebral Aβ clearance, and attenuate cognitive deficits in AD transgenic mouse models. Discovery of such antineuroinflammatory compounds signifies the potential in discovering effective therapeutic molecules against AD-associated neurodegeneration.

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