Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Conserved epigenomic signatures between mouse and human elucidate immune basis of Alzheimer's disease

ABSTRACT: Alzheimer’s disease (AD) is a severe1 age-related neurodegenerative disorder characterized by accumulation of beta-amyloid (Aβ) plaques and neurofibrillary tangles, synaptic and neuronal loss, and cognitive decline. Several genes have been implicated in AD, but chromatin state alterations during neurodegeneration remain uncharacterized. Here, we profile transcriptional and chromatin state dynamics across early and late pathology in the hippocampus of an inducible mouse model of AD-like neurodegeneration. We find a coordinated downregulation of synaptic plasticity genes and regulatory regions, and upregulation of immune response genes and regulatory regions, which are targeted by factors that belong to the ETS family of transcriptional regulators, including PU.1. Human regions orthologous to increasing-level enhancers show immune cell-specific enhancer signatures as well as immune cell expression quantitative trait loci (eQTL), while decreasing-level enhancer orthologs show fetal brain specific enhancer activity. Surprisingly, AD-associated genetic variants are specifically enriched in increasing-level enhancer orthologs implicating immune processes in AD predisposition. Indeed, increasing enhancers overlap known AD loci lacking protein-altering variants and implicate additional loci that do not reach genome-wide significance. Our results reveal new insights into the mechanisms of neurodegeneration and establish the mouse as a useful model for functional studies of AD regulatory regions.

ORGANISM(S): Mus musculus

PROVIDER: GSE65159 | GEO | 2015/02/18

SECONDARY ACCESSION(S): PRJNA273302

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Conserved epigenomic signatures between mouse and human elucidate immune basis of Alzheimer's disease

Project description:Alzheimer’s disease (AD) is a severe1 age-related neurodegenerative disorder characterized by accumulation of beta-amyloid (Aβ) plaques and neurofibrillary tangles, synaptic and neuronal loss, and cognitive decline. Several genes have been implicated in AD, but chromatin state alterations during neurodegeneration remain uncharacterized. Here, we profile transcriptional and chromatin state dynamics across early and late pathology in the hippocampus of an inducible mouse model of AD-like neurodegeneration. We find a coordinated downregulation of synaptic plasticity genes and regulatory regions, and upregulation of immune response genes and regulatory regions, which are targeted by factors that belong to the ETS family of transcriptional regulators, including PU.1. Human regions orthologous to increasing-level enhancers show immune cell-specific enhancer signatures as well as immune cell expression quantitative trait loci (eQTL), while decreasing-level enhancer orthologs show fetal brain specific enhancer activity. Surprisingly, AD-associated genetic variants are specifically enriched in increasing-level enhancer orthologs implicating immune processes in AD predisposition. Indeed, increasing enhancers overlap known AD loci lacking protein-altering variants and implicate additional loci that do not reach genome-wide significance. Our results reveal new insights into the mechanisms of neurodegeneration and establish the mouse as a useful model for functional studies of AD regulatory regions. We profiled gene expression levels through RNA-Seq and histone mark levels through ChIP-Seq to compare control mice to the CK-p25 Alzheimer's disease model at 2 weeks and 6 weeks after induction of neurodegeneration.

2015-02-18 | E-GEOD-65159 | biostudies-arrayexpress

Microglia-specific loss of PU.1 function rescues neurodegenerative phenotypes in a mouse model of Alzheimer’s disease

Project description:Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by progressive decline of cognitive ability. An important component of AD, and other chronic neurodegenerative diseases, is generation of an innate inflammatory response within the CNS, characterized by activation of microglia, the resident immune cells of the brain. Transcription factor PU.1 has been known to play an important role in myeloid and lymphoid cell development, however its function in microglia and how it contributes to disease pathology is not well understood. Using transcriptional and chromatin state profiles during AD-like pathology in the CK-p25 mouse model of neurodegeneration, we showed that PU.1 specifically targets noncoding regions which regulate expression changes of immune response genes during AD, suggesting it may act as master regulator of microglia activation. Here, we examine the role of PU.1 in neurodegeneration by using a conditional knockout (cKO) cassette (Cx3cr1CreER+/-) to inducibly deplete PU.1 from microglia in the CK-p25 mouse model of neurodegeneration. We found that knocking out PU.1 rescues multiple neurodegenerative phenotypes. Specifically, PU.1 inhibition reduces neurodegeneration-specific increase in microglia cell number, improves neuronal survival and reverses functional synaptic plasticity deficits in the hippocampus of the CK-p25 mouse.

2021-01-01 | GSE117868 | GEO

The transcription factor Sp3 cooperates with HDAC2 to regulate synaptic function and plasticity in neurons

Project description:The histone deacetylase HDAC2, which negatively regulates neuronal plasticity and synaptic gene expression, is upregulated both in Alzheimer’s disease (AD) patients and mouse models (Graff et al., 2012). Therapeutics targeting HDAC2 are speculated to be a promising avenue for ameliorating AD related cognitive impairment. However, attempts to generate HDAC2-specific inhibitors have not been successful. Here, we take a novel approach utilizing integrative genomics to identify proteins that mediate HDAC2 recruitment to synaptic plasticity genes. Functional screening revealed that knockdown of the transcription factor Sp3 phenocopied HDAC2 knockdown, and that Sp3 facilitated the recruitment of HDAC2 to synaptic genes. Importantly, like HDAC2, Sp3 expression was elevated in AD patients and mouse models, where Sp3 knockdown ameliorated synaptic dysfunction. Furthermore, exogenous expression of an HDAC2 fragment containing the Sp3 binding domain fully restored synaptic plasticity and memory in a mouse model with severe neurodegeneration. Our findings indicate that targeting the HDAC2-Sp3 complex could enhance synaptic and cognitive function, without affecting HDAC2 function in other processes.

2017-08-08 | GSE87441 | GEO

Molecular signatures underlying neurofibrillary tangle susceptibility in Alzheimer’s disease

Project description:Tau aggregation in neurofibrillary tangles (NFTs) is closely associated with neurodegeneration and cognitive decline in Alzheimer’s disease (AD). However, the molecular signatures that distinguish between aggregation-prone and aggregation-resistant cell states are unknown. We developed methods for the high-throughput isolation and transcriptome profiling of single somas with NFTs fro¬m human AD brain, quantified the susceptibility of 20 neocortical subtypes for NFT formation and death, and identified both shared and cell-type-specific signatures. NFT-bearing neurons shared a marked upregulation of synaptic transmission-related genes, including a core set of 63 genes enriched for synaptic vesicle cycling. Oxidative phosphorylation and mitochondrial dysfunction were highly cell-type dependent. Apoptosis was only modestly enriched, and the susceptibilities of NFT-bearing and NFT-free neurons for death were highly similar. Our analysis suggests that NFTs represent cell-type-specific responses to stress and synaptic dysfunction. We provide a resource for biomarker discovery and the investigation of tau-dependent and tau-independent mechanisms of neurodegeneration.

2020-08-05 | GSE129308 | GEO

Neuronal ApoE Upregulates MHC-I Expression to Drive Selective Neurodegeneration in Alzheimer’s Disease

Project description:Selective neurodegeneration is a critical causal factor in Alzheimer’s disease (AD); however, the mechanisms that lead some neurons to perish while others remain resilient are unknown. We sought potential drivers of this selective vulnerability using single-nucleus RNA sequencing and discovered that apoE expression level is a substantial driver of neuronal variability. Strikingly, neuronal expression of apoE—which has a robust genetic linkage to AD—correlated strongly, on a cell-by-cell basis, with immune response pathways in neurons in the brains of wildtype mice, human apoE knock-in mice, and humans with or without AD. Elimination or over-expression of neuronal apoE revealed a causal relationship between apoE expression, neuronal MHC-I expression, Tau pathology, and neurodegeneration. Functional reduction of MHC-I ameliorated Tau pathology in apoE4-expressing primary neurons and in mouse hippocampi expressing pathological Tau. These findings suggest a mechanism linking neuronal apoE expression to MHC-I expression and, subsequently, to Tau pathology and selective neurodegeneration.

2021-04-19 | GSE167497 | GEO

Alzheimer's Disease Dataset

Project description:This dataset contains microarray data from normal controls (aged 20-99 yrs) and Alzheimer's disease cases, from 4 brain regions: hippocampus, entorhinal cortex, superior frontal cortex, post-central gyrus. Changes in expression of synaptic and immune related genes were analyzed, investigating age-related changes and AD-related changes, and region-specific patterns of change. These AD cases were processed simultaneously with the control cases (young and aged) included in GSE11882 (GSE11882 dataset contains data exclusively from normal control brains).

2014-04-21 | GSE48350 | GEO

Microglia-mediated T cell Infiltration Drives Neurodegeneration in Tauopathy

Project description:Extracellular amyloid-β (Aβ) deposition as neuritic plaques and intracellular accumulation of hyperphosphorylated, aggregated tau as neurofibrillary tangles (NFT) are two of the characteristic hallmarks in Alzheimer’s disease (AD). The regional progression of brain atrophy in AD highly correlates with tau accumulation but not amyloid deposition and the mechanisms of tau-mediated neurodegeneration remain elusive. Innate immune responses represent a common pathway for the initiation and progression of some neurodegenerative diseases. To date, little is known about the extent or role of the adaptive immune response in the presence of Aβ or tau pathology. We systematically compared the immunological milieus in the brain of mice with amyloid deposition or tau aggregation and neurodegeneration. We found that mice with tauopathy but not amyloid, developed a unique innate and adaptive immune response and that depletion of microglia or T-cells blocked tau-mediated neurodegeneration. T cells, especially cytotoxic T cells, were markedly increased in areas with tau pathology in mice with tauopathy and in the AD brain. T cell numbers correlated with the extent of neuronal loss, and dynamically transformed their cellular characteristics from activated to exhausted states along with unique TCR clonal expansion. Inhibition of IFN-γ and PD-1signaling both significantly ameliorated brain atrophy. Our results thus reveal a tauopathy and neurodegeneration-related immune hub involving activated microglia and T cell responses, which could serve as therapeutic targets for preventing neurodegeneration in AD and primary tauopathies.

2023-03-01 | GSE221856 | GEO

Modeling sporadic Alzheimer’s disease in human brain organoids under serum exposure

Project description:Although sporadic AD (sAD) accounts for the majority of AD cases, the underlying mechanisms remain largely unknown. Here we modeled sAD using human induced pluripotent stem cell (iPSC)-derived three-dimensional brain organoids. We exposed brain organoids to serum to mimic the serum exposure consequence of BBB breakdown in AD patient brains. The serum-exposed brain organoids were able to recapitulate AD-like pathologies, including increased Aβ aggregates and p-Tau level, synaptic loss, and impaired calcium signaling and neural network. Serum exposure increased Aβ and p-Tau levels through inducing BACE and GSK3α/β levels, respectively. In addition, single-cell transcriptomic analysis of brain organoids revealed that serum exposure reduced synaptic function in both neurons and astrocytes, and induced immune response in astrocytes. The human brain organoid-based sAD model established in this study could provide a powerful platform for both mechanistic study and therapeutic development.

2021-09-29 | GSE164089 | GEO

Molecular Signatures Underlying Selective Regional Vulnerability to Alzheimer's Disease

Project description:Alzheimer's disease (AD) is the most common form of dementia, characterized by progressive cognitive impairment and neurodegeneration as a result of abnormal neuronal loss. To elucidate the molecular systems associated with AD, we characterized the gene expression changes associated with multiple clinical and neuropathological traits in 1,053 postmortem brain samples across 19 brain regions from 125 persons dying with varying severities of dementia and variable AD-neuropathology severities. 125 human brains were accessed from the Mount Sinai/JJ Peters VA Medical Center Brain Bank (MSBB). This brain resource was assembled after applying stringent inclusion/exclusion criteria and represents the full spectrum of clinical and neuropathological disease severity in the absence of discernable non-AD neuropathology. RNA samples from 19 brain regions isolated from the 125 MSBB specimens were collected and profiled using Affymetrix Genechip microarrays. There were 50 to 60 subjects per brain region with varying degrees of AD pathological abnormalities.

2016-08-19 | E-GEOD-84422 | biostudies-arrayexpress

Molecular Signatures Underlying Selective Regional Vulnerability to Alzheimer's Disease

2016-08-19 | GSE84422 | GEO