Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Jedi-1/MEGF12-mediated phagocytosis controls the pro-neurogenic properties of microglia in the ventricular-subventricular zone

ABSTRACT: Microglia are the primary phagocytes in the central nervous system and are responsible for clearing dead cells generated during development or disease. The phagocytic process shapes the phenotype of the microglia, which affects the local environment. A unique population of microglia reside in the ventricular-subventricular zone (V-SVZ) of neonatal mice, but how they influence this neurogenic niche is not well-understood. Here, we demonstrate that phagocytosis creates a pro-neurogenic microglial phenotype in the V-SVZ and that these microglia phagocytose apoptotic cells via the engulfment receptor Jedi-1. Deletion of Jedi-1 decreases apoptotic cell clearance, triggering the development of a neuroinflammatory phenotype, reminiscent of neurodegenerative and-age-associated microglia, that reduces neural precursor proliferation via elevated interleukin (IL)-1β signaling; inhibiton of IL-1 receptor rescues precursor proliferation in vivo. Together, these results reveal a critical role for Jedi-1 in connecting microglial phagocytic activity to a phenotype that promotes neurogenesis in the developing V-SVZ. We performed RNAseq on MACS-sorted microglia from V-SVZ and Cortex of WT and Jedi-1 knockout P7 mice.

ORGANISM(S): Mus musculus

PROVIDER: GSE232441 | GEO | 2024/02/15

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Defining the microglial transcriptome in the rat subventricular zone (SVZ) after neonatal hypoxia-ischemia (HI).

Project description:Purpose: Recent findings indicate a regulatory role of microglia on neurogenesis in the SVZ in health and disease. Microglia in the early postnatal SVZ are not fully maturated and may react differently than adult microglia to injury. We sought to investigate the impact of cortico-striatal neonatal HI injury on the microglial phenotype in the early postnatal SVZ. Results: In comparison to sham SVZ microglia, HI SVZ microglia upregulate both pro- and anti-inflammatory genes as well as neurotrophic genes. HI SVZ microglia do not adopt a M1 or M2 polarization state, but instead share commonly expressed genes with microglia in rodent models of neurodegenerative diseases.

2020-01-13 | GSE97299 | GEO

IL-33-PU.1 transcriptome reprogramming drives functional state transition and clearance activity of microglia in Alzheimer’s disease

Project description:Impairment of microglial clearance activity contributes to beta-amyloid (Aβ) pathology in Alzheimer disease (AD). While the transcriptome profile of microglia directs microglial functions, how the microglial transcriptome can be regulated to alleviate AD pathology is largely unknown. Here, we show that injection of interleukin (IL)-33 in an AD transgenic mouse model ameliorates Aβ pathology by reprogramming microglial epigenetic and transcriptomic profiles to induce a microglial subpopulation with enhanced phagocytic activity. These IL-33–responsive microglia (IL-33RM) express distinct transcriptome signature, highlighted by major histocompatibility complex class II genes, and restored homeostatic signature genes. IL-33–induced remodeling of chromatin accessibility and PU.1 transcription factor binding at the signature genes of IL-33RM control their transcriptome reprogramming. Specifically, disrupting PU.1–DNA interaction abolishes the microglial state transition and Aβ clearance induced by IL-33. Thus, we define a PU.1-dependent transcriptional pathway that drives the IL-33–induced functional state transition of microglia, resulting in enhanced Aβ clearance.

2020-05-01 | GSE147495 | GEO

Proteome integral solubility alteration high-throughput proteomics assay identifies Collectin-12 as a non-apoptotic microglial caspase-3 substrate.

Project description:Caspases are a family of proteins mostly known for their role in the activation of the apoptotic pathway leading to cell death. In the last decade, caspases have been found to fulfil other tasks regulating the cell phenotype independently to cell death. Microglia are the immune cells of the brain responsible for the maintenance of physiological brain functions but can also be involved in disease progression when overactivated. We have previously described non30 apoptotic roles of caspase-3 (CASP3) in the regulation of the inflammatory phenotype of microglial cells or pro-tumoral activation in the context of brain tumors. CASP3 can regulate protein functions by cleavage of their target and therefore could have multiple substrates. So far, identification of CASP3 substrates has been performed mostly in apoptotic conditions where CASP3 activity is highly upregulated and these approaches do not have the capacity to uncover CASP3 substrates at the physiological level. In our study, we aim at discovering highaffinity substrates of CASP3 involved in the normal regulation of the cell. We used an unconventional approach by chemically reducing the basal level activity of CASP3 (by DEVD38 fmk treatment) coupled to a Mass Spectrometry screen (PISA) to identify stabilized, and consequently, non-cleaved proteins in microglia cells. PISA identified several significantly stabilized proteins after DEVD-fmk treatment, including a few already known CASP3substrates which validated our approach. Among them, we focused on the Collectin12 (COLEC12 or CL-P1) transmembrane receptor and uncovered a potential role for CASP3 cleavage of COLEC12 in the regulation of the phagocytic capacity of microglial cells. Taken together, these findings suggest a new way to uncover non-apoptotic high-affinity substrates of CASP3 important for the modulation of microglia cell physiology.

2023-05-10 | PXD032835 | Pride

SIRT1 deficiency in microglia contributes to cognitive decline in aging and neurodegeneration via epigenetic regulation of IL-1beta

Project description:Aging is the predominant risk factor for neurodegenerative diseases. One key phenotype as brain ages is the aberrant innate immune response characterized by proinflammation. However, the molecular mechanisms underlying aging-associated proinflammation are poorly defined. Whether chronic inflammation plays a causal role in cognitive decline in aging and neurodegeneration has not been established. Here we established a mechanistic link between chronic inflammation and aging microglia, and demonstrated a causal role of aging microglia in neurodegenerative cognitive deficits. Expression of microglial SIRT1 reduces with the aging of microglia. Genetic reduction of microglial SIRT1 elevates IL-1Î² selectively, and exacerbates cognitive deficits in aging and in transgenic mouse models of frontotemporal dementia (FTD). Interestingly, the selective activation of IL-1Î² transcription by SIRT1 deficiency is likely mediated through hypomethylating the proximal promoter of IL-1Î². Consistent with our findings in mice, selective hypomethylation of IL-1Î² at two CpG sites are found in normal aging humans and demented patients with tauopathy. Our findings reveal a novel epigenetic mechanism in aging microglia that contributes to cognitive deficits in neurodegenerative diseases. Study of changes related to alterations of SIRT1 levels in microglia of young and aged animals and in models of neurodegenerative dementia

2014-10-01 | E-GEOD-56452 | biostudies-arrayexpress

Microglia actively remodels adult hippocampal neurogenesis through the phagocytosis secretome

Project description:During adult hippocampal neurogenesis, the majority of newborn cells undergo apoptosis and are rapidly phagocytosed by resident microglia in order to avoid disturbing the surrounding neurons. Here, we propose that phagocytosis is not merely a passive process of corpse removal but has an active role in maintaining adult hippocampal neurogenesis. First, we found that neurogenesis was disrupted in three defective microglial phagocytosis KO models in vivo (P2Y12, MerTK/Axl , GPR34). We then followed an in vitro approach to perform a transcriptomic analysis of microglial phagocytosis and identified genes involved in metabolism, chromatin remodeling, and neurogenesis-related functions. Finally, we determined that the phagocytic microglia secretome limits the production of new neurons both in vivo and in vitro. Our data suggest that reprogrammed phagocytic microglia acts as a sensor of local cell death, modulating the balance between cell proliferation and cell survival in the neurogenic niche, supporting the long-term maintenance of adult hippocampal neurogenesis.

2020-04-09 | GSE129569 | GEO

The VCAM1–ApoE pathway directs microglial chemotaxis and alleviates Alzheimer’s disease pathology

Project description:In Alzheimer’s disease (AD), sensome receptor dysfunction impairs microglial danger-associated molecular pattern (DAMP) clearance and exacerbates disease pathology. While extrinsic signals including interleukin-33 (IL-33) can restore microglial DAMP clearance, it remains largely unclear how the sensome receptor(s) is regulated and interacts with DAMP during phagocytic clearance. Here, we show that IL-33 induces VCAM1 in microglia, which promotes microglial chemotaxis toward amyloid-beta (Aβ) plaque-associated ApoE, and leads to Aβ clearance. We show that IL-33 stimulates a chemotactic state in microglia, characterized by Aβ-directed migration. Functional screening identified that VCAM1 directs microglial Aβ chemotaxis by sensing Aβ plaque-associated ApoE. Moreover, we found that disrupting VCAM1–ApoE interaction abolishes microglial Aβ chemotaxis, resulting in decreased microglial clearance of Aβ. In patients with AD, higher cerebrospinal fluid levels of soluble VCAM1 were correlated with impaired microglial Aβ chemotaxis. Together, our findings demonstrate that promoting VCAM1–ApoE-dependent microglial functions ameliorates AD pathology.

2023-07-18 | GSE208006 | GEO

Naturally-aged microglia exhibit phagocytic dysfunction accompanied by gene expression changes reflective of underlying neurologic disease

Project description:Age-associated microglial dysfunction contributes to the accumulation of amyloid-b (Ab) plaques in Alzheimer’s disease. Although several studies have shown age-related declines in the phagocytic capacity of myeloid cells, relatively few have examined phagocytosis of normally aged microglia. Furthermore, much of the existing data on aging microglial function have been generated in accelerated genetic models of Alzheimer’s disease. Here we found that naturally aged microglia phagocytosed less Ab over time. To gain a better understanding of such dysfunction, we assessed differences in gene expression between young and old microglia that either did or did not phagocytose Ab. Young microglia had both phagocytic and neuronal maintenance signatures indicative of normal microglial responses, whereas, old microglia, regardless of phagocytic status, exhibit signs of broad dysfunction reflective of underlying neurologic disease states. We also found downregulation of many phagocytic receptors on old microglia, including TREM2, an Ab phagocytic receptor. TREM2 protein expression was diminished in old microglia and loss of TREM2+ microglia was correlated with impaired Ab uptake, suggesting a mechanism for phagocytic dysfunction in old microglia. Combined, our work reveals that normally aged microglia have broad changes in gene expression, including defects in Ab phagocytosis that likely underlies the progression to neurologic disease.

2022-06-10 | GSE205803 | GEO

The role of CD11C positive and negative microglia populations in Neuromyelitis optica

Project description:Background: Tissue macrophages contribute to development and protection, both requiring appropriately timed and located source(s) of factors controlling growth, cell differentiation and migration. Goal: To understand the role of microglia (tissue macrophages of the central nervous system), in promoting neurodevelopment and controlling neuroinflammation. Summary of findings: We show that microglia fulfill both these roles. In contrast to adult cells, neonatal microglia show a unique neurogenic phenotype with stem cell-like potential. Neonatal microglia are protective against neuroinflammation, and their transplantation ameliorates experimental autoimmune encephalomyelitis. A CD11c+ microglial subset predominates in primary myelinating areas of the developing brain and expresses genes for neuronal and glial survival, migration and differentiation. CD11c+ microglia are also found in clusters of repopulating microglia after experimental ablation and in neuroinflammation in adult mice, but despite some similarities, they do not recapitulate neurogenic neonatal microglia characteristics. Conclusions: We therefore identify a unique phenotype of neonatal microglia that deliver signals necessary for neurogenesis and myelination and suppress neuroinflammation.

2020-12-01 | GSE98784 | GEO

Novel neuroprotective and neurogenic phenotype of microglia

2017-09-25 | GSE78809 | GEO

TREM2 interacts with TDP-43 and mediates microglial neuroprotection against TDP-43-related neurodegeneration

Project description:Triggering receptor expressed on myeloid cell 2 (TREM2) is linked to neurodegenerative disease risk. However, the function of TREM in neurodegeneration is still unclear. Here we investigated the role of microglial TREM2 in TAR-DNA binding protein 43 kDa (TDP-43)-related neurodegeneration using viral-mediated and transgenic mouse models. We found that TREM2 deficiency impaired phagocytic clearance of pathological TDP-43 by microglia, and enhanced neuronal damage and motor impairments. Mass cytometry analysis revealed that hTDP-43 induced a TREM2-dependent subpopulation of microglia with high CD11c expression and phagocytic ability. Using mass spectrometry and surface plasmon resonance analysis, we further demonstrated an interaction between TDP-43 and TREM2 in vitro and in vivo as well as in ALS patient tissues. We computationally identified the region within hTDP-43 that interacts with TREM2. Our data highlights that TDP-43 is a possible ligand for microglial TREM2 and that this interaction mediates neuroprotection effects of microglia in TDP-43-related neurodegeneration.

2022-08-12 | PXD029429 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data