ABCA7 haplodeficiency disrupts microglial inflammatory responses and membrane trafficking
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE139592 | GEO | 2019/10/31
REPOSITORIES: GEO
Similar Datasets
Project description:ABCA7 haplodeficiency disrupts microglial inflammatory responses and membrane trafficking
| PRJNA580442 | ENA
Project description:ABCA7 loss-of-function variants are associated with increased risk of Alzheimer’s disease (AD). Using ABCA7 knockout human iPSC models generated with CRISPR/Cas9, we investigated the impacts of ABCA7 deficiency on neuronal metabolism and function. Lipidomics revealed that mitochondria-related phospholipids, such as phosphatidylglycerol and cardiolipin were reduced in the ABCA7-deficient iPSC-derived cortical organoids. Consistently, ABCA7 deficiency induced alterations of mitochondrial morphology accompanied by reduced ATP synthase activity and exacerbated oxidative damage in the organoids.
2024-01-17 | GSE247360 | GEO
Project description:Aortic dissection (AD) is a major cause of acute aortic syndrome with high mortality due to the destruction of aortic walls. Although recent studies indicate the critical role of inflammation in the disease mechanism of AD, it is unclear how inflammatory response is initiated. Here, we demonstrate that myocardin-related transcription factor A (MRTF-A), a signal transducer of humoral and mechanical stress, plays an important role in pathogenesis of AD in a mouse model. A mouse model of AD was created by continuous infusion of angiotensin II (AngII) that caused dilation of thoracic aorta in 1 day and AD in 4 days. Systemic deletion of Mrtfa gene resulted in a marked suppression of AD development. Transcriptome and gene annotation enrichment analyses revealed that AngII infusion for 1 day caused pro-inflammatory and pro-apoptotic responses before AD development, which were suppressed by Mrtfa deletion. AngII infusion for 1 day induced pro-inflammatory response, as demonstrated by expressions of Il6, Tnf , and Ccl2, and apoptosis of aortic wall cells, as detected by TUNEL staining, in an MRTF-A-dependent manner. Furthermore, pharmacological inhibition of MRTF-A by CCG-203971 during AngII infusion prevented AD development, indicating that acute suppression of MRTF-A is effective in preventing the aortic wall destruction. These results indicate that MRTF-A transduces the stress of AngII challenge to the pro-inflammatory and pro-apoptotic responses, ultimately leading to AD development. Intervening this pathway may represent a potential therapeutic strategy.
2020-04-01 | GSE138484 | GEO
Project description:Microglia are innate immune cells of the brain that perform phagocytic and inflammatory functions in disease conditions. Transcriptomic studies of acutely-isolated microglia have provided novel insights into their molecular and functional diversity in homeostatic and neurodegenerative disease states. State-of-the-art mass spectrometric methods can comprehensively characterize proteomic alterations in microglia in neurodegenerative disorders, potentially providing novel functionally-relevant molecular insights that are not provided by transcriptomics. However, proteomic profiling of adult primary microglia in neurodegenerative disease conditions has not been performed. We performed quantitative proteomic analyses of purified CD11b+ acutely-isolated microglia adult mice in normal, acute neuroinflammatory (LPS-treatment) and chronic neurodegenerative states (5xFAD model of Alzheimer’s disease [AD]) using tandem mass tag mass spectrometry. Differential expression analyses were performed to characterize specific microglial proteomic changes in 5xFAD mice and identify overlap with LPS-induced pro-inflammatory changes. Our results were also contrasted with existing proteomic data from wild-type mouse microglia and from existing microglial transcriptomic data from wild-type and 5xFAD mice. Neuropathological validation studies of select proteins were performed in human AD and 5xFAD brains. Of 4,133 proteins identified, 187 microglial proteins were differentially expressed in the 5xFAD mouse model of AD pathology, including proteins with previously known (Apoe, Clu and Htra1) as well as previously unreported relevance to AD biology (Cotl1 and Hexb). Proteins upregulated in 5xFAD microglia shared significant overlap with pro-inflammatory changes observed in LPS-treated mice. Several proteins increased in human AD brain were also upregulated by 5xFAD microglia (Aβ peptide, Apoe, Htra1, Cotl1 and Clu). Cotl1 was identified as a novel microglia-specific marker with increased expression and strong association with AD neuropathology. Apoe protein was also detected within plaque-associated microglia in which Apoe and Aβ were highly co-localized suggesting a role for Apoe in phagocytic clearance of Aβ. We report the first comprehensive comparative proteomic study of adult mouse microglia derived from acute neuroinflammatory and AD models, representing a valuable resource to the neuroscience research community. We highlight shared and unique microglial proteomic changes in acute neuroinflammatory, aging and AD mouse models in addition to identifying novel roles for microglial proteins in human neurodegeneration.
2018-09-18 | PXD009137 | Pride
Project description:To identify the m6A methylome in the aorta of patients with acute aortic dissection. MeRIP-seq and RNA-seq experiments of aortic media tissue samples obtained from AD patients and controls were conducted. Compared with control group, the upmethylated coding genes of AD were primarily enriched in the processes associated with extracellular fibril organization, while the genes with downmethylation were enriched in the processes associated with cell death regulation. Furthermore, many differentially methylated m6A sites (DMMSs) coding proteins were mainly annotated during the extracellular matrix and inflammatory responses.
2020-03-17 | GSE147027 | GEO
Project description:To identify the m6A methylome in the aorta of patients with acute aortic dissection. MeRIP-seq and RNA-seq experiments of aortic media tissue samples obtained from AD patients and controls were conducted. Compared with control group, the upmethylated coding genes of AD were primarily enriched in the processes associated with extracellular fibril organization, while the genes with downmethylation were enriched in the processes associated with cell death regulation. Furthermore, many differentially methylated m6A sites (DMMSs) coding proteins were mainly annotated during the extracellular matrix and inflammatory responses.
2020-03-17 | GSE147026 | GEO
Project description:More than forty loci contribute to genetic risk for Alzheimer’s disease (AD). These risk alleles are enriched in myeloid cell enhancers suggesting that microglia, the brain-resident macrophages, contribute to AD risk. We have previously identified SPI1/PU.1, a master regulator of myeloid cell development in the brain and periphery, as a genetic risk factor for AD. Higher expression of SPI1 is associated with increased risk for AD, while lower expression is protective. To investigate the molecular and cellular phenotypes associated with higher and lower expression of PU.1 in microglia, we used stable overexpression and knock-down of PU.1 in BV2, an immortalized mouse microglial cell line. Transcriptome analysis suggests that reduced PU.1 expression suppresses expression of homeostatic genes similar to the disease-associated microglia response to amyloid plaques in mouse models of AD. Moreover, PU.1 knock-down resulted in activation of protein translation, antioxidant action and cholesterol/lipid metabolism pathways with a concomitant decrease of pro-inflammatory gene expression. PU.1 overexpression upregulated and knock-down downregulated phagocytic uptake in BV2 cells independent of the nature of the engulfed material. However, cells with reduced PU.1 expression retained their ability to internalize myelin similar to control albeit with a delay, which aligns with their anti-inflammatory profile. Here we identified several microglial responses that are modulated by PU.1 expression levels and propose that risk association of PU.1 to AD is driven by increased pro-inflammatory response due to increased viability of cells under cytotoxic conditions. In contrast, low expression of PU.1 leads to increased cell death under cytotoxic conditions accompanied by reduced pro-inflammatory signaling that decreased A1 reactive astrocytes signature supporting the protective effect of SPI1 genotype in AD. These findings inform future in vivo validation studies and design of small molecule screens for therapeutic discovery in AD.
2020-12-07 | GSE162526 | GEO
Project description:Background: Iron trafficking and accumulation has been associated with Alzheimer’s disease (AD) pathogenesis. However, the role of iron dyshomeostasis in early disease stages is uncertain. Currently, gene expression changes indicative of iron dyshomeostasis are not well characterised, making it difficult to explore these in existing datasets. Results: We identified sets of genes predicted to contain Iron Responsive Elements (IREs), and used these to explore iron dyshomeostasis responses in transcript datasets involving (1) cultured cells under iron overload and deficiency treatments, (2) post-mortem brain tissues from AD and other neuropathologies, (3) 5XFAD transgenic mice modelling AD pathologies, and (4) a zebrafish knock-in model of early-onset, familial AD (fAD). IRE gene sets were sufficiently sensitive to distinguish not only between iron overload and deficiency in cultured cells, but also between AD and other pathological brain conditions. Notably, we see changes in 3’ IRE transcript abundance as amongst the earliest observable in zebrafish fAD-like brains and preceding other AD-typical pathologies such as inflammatory changes. Unexpectedly, while some 3’ IRE transcripts show significantly increased stability under iron deficiency in line with current assumptions, many such transcripts instead show decreased stability, indicating that this is not a generalizable paradigm. Conclusions: Our results reveal iron dyshomeostasis as a likely early driver of fAD and as able to distinguish AD from other brain pathologies. Our work demonstrates how differences in the stability of IRE-containing transcripts can be used to explore and compare iron dyshomeostasis responses in different species, tissues, and conditions.
2020-05-06 | GSE149149 | GEO
Project description:Replication-deficient adenovirus (Ad) type 5 capsids induce potent host innate immune responses. One system pivotal in host innate immune defense is the complement system. Intriguingly, excessive or inappropriate complement activation can result in extreme tissue damage and systemic inflammatory responses similar to those noted immediately after high dose systemic Ad vector injections. To determine if the complement system has a significant role in intensifying Ad-associated acute toxicities, we compared complement deficient (C3-knockout (KO)) mice responses to those of wild type (WT) mice following systemic challenge with Ad vectors. We noted not only thrombocytopenia and rapid increases in plasma IL-6, IFN-γ, TNF-α, and IL-12 levels previously reported after high dose Ad injections into WT mice, but also induction of cytokines IL-2, IL-4, IL-5 and IL-10, G-CSF and GM-CSF, and chemokines KC (CXCL1) and MIP-1. This expanded innate response “profile” was significantly blunted in Ad injected C3-KO mice, with a near complete avoidance of thrombocytopenia. Further validation for complement’s critical role in perturbing these innate responses against Ad were noted after comparison of gene specific RNA transcription levels in C3-KO to WT mice livers. Finally, these disparities were not attributed to a diminished ability of the Ad vectors to transduce C3-KO mice hepatocytes. These results suggest that Ad capsid interaction with the mammalian complement system may exacerbate the toxicity of systemic Ad injections, and thus represents a future target for manipulation in efforts to improve the efficacy and safety profile of Ad mediated gene delivery. Keywords: adenovirus, complement system, time course, innate immune response, toxicity
2006-02-15 | GSE4128 | GEO
Project description:Immune cell infiltration to the brain is a prominent feature in aging and in various neurodegenerative diseases such as Alzheimer´s disease (AD). For example, a specific subpopulation of CD8+ T-cells clonally expands in the CSF of AD patients. Also, with AD progression that typically includes amyloid-beta plaque formation, neuronal damage and microglia-associated neuroinflammation, CD8+ T-cells infiltrate into the AD brain parenchyma and tightly associate with neuronal and microglia structures. The functional properties of CD8+ T-cells in the brain are largely unknown, besides the fact that experimental ablation in a transgenic AD animal model (APP-PS1) leads to changes in the expression of neuronal- and synapse-related genes. To gain further insights into the putative functional role of CD8+ T-cells in the brain, we explored and compared the transcriptomic profile of these cells in blood and brain of aged and transgenic AD mice. Surprisingly, CD8+ T-cells isolated from brains of aged APP-PS1 and WT animals had a similar transcriptomic profile, but they substantially differed from blood circulating CD8+ T-cells. The gene expression signature of brain CD8+ T-cells from APP-PS1 mice identified these cells as tissue-resident memory T-cells (Trm) indicated by specific regulation of genes such as Klf2/3, Ccr7, Sell, and Cxcr6. Immunohistochemical analysis confirmed the Trm identity of CD8+ T-cells at sites of amyloid-plaques. Gene ontology enrichment analysis on the significantly up-regulated genes showed an overrepresentation of biological processes as “response to virus”, “T-cell mediated immunity” and “response to interferon-beta” suggesting similarities to virus-responding T-cells. This is also supported by KEGG analysis, which highlighted upregulation of several pathways for “virus infections”, “cellular senescence” and “antigen processing and presentation”. In addition, the transcriptome of APP-PS1 brain CD8+ T-cells overlapped with gene microarray data of brain Trm CD8+ T-cells derived from an acute virus infection mouse model, suggesting similar functions of CD8+ T-cells in the brain either after viral infections or in AD. In conclusion, our herein presented data give new insights on the transcriptome of brain CD8+ T-cells and demonstrate adaptive immune responses in transgenic AD mice. This might open the door for immunotherapy as potential treatment option for AD.
2022-08-02 | GSE180746 | GEO