Local calcium accumulations promote phagocyte-mediated synapse removal in cortical neuroinflammation
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA679032 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Cortical pathology contributes to chronic cognitive impairment of patients suffering from the neuroinflammatory disease multiple sclerosis (MS). How such gray matter inflammation affects neuronal structure and function is not well understood. Here we use functional and structural in vivo imaging in a mouse model of cortical MS to demonstrate that bouts of cortical inflammation disrupt cortical circuit activity coincident with a widespread, but transient loss of dendritic spines. Spines destined for removal show local calcium accumulations and are subsequently removed by invading macrophages or activated microglia. Targeting phagocyte activation with a new antagonist of the colony-stimulating factor 1 receptor prevents cortical synapse loss. Overall, our study identifies synapse loss as a key pathological feature of inflammatory gray matter lesions that is amenable to immunomodulatory therapy.
2021-02-22 | GSE161654 | GEO
Project description:Microglia-expressed A20 regulates synapse formation and inhibits inflammasome-dependent neuroinflammation
| PRJNA421210 | ENA
Project description:Neuroinflammation plays a role in the progression of several neurodegenerative disorders. We used a lipolysaccharide (LPS) model of neuroinflammation to characterize the gene expression changes underlying the inflammatory and behavioral effects of neuroinflammation. A single intracerebroventricular injection of LPS (5 ug) was administered into the lateral ventricle of mice and, 24 hours later, we examined gene expression in the cerebral cortex and hippocampus using microarray technology. Gene Ontology (GO) terms for inflammation and the ribosome were significantly enriched by LPS, whereas GO terms associated with learning and memory had decreased expression. We detected 224 changed transcripts in the cerebral cortex and 170 in the hippocampus. Expression of Egr1 (also known as Zif268) and Arc, two genes associated with learning and memory, was significantly lower in the cortex, but not hippocampus, of LPS-treated animals. Overall, altered expression of these genes may underlie some of the inflammatory and behavioral effects of neuroinflammation. Mice were given intracerebroventricular injections of saline vehicle (n = 4) or lipopolysaccharide (n = 4). Twenty-four hours later, we dissected the hippocampus and cerebral cortex and processed the tissue for microarray analysis. Gene expression changes observed in the microaray data were validated with quantitative real-time PCR.
2008-11-01 | E-GEOD-12284 | biostudies-arrayexpress
Project description:Neurons use local protein synthesis to support their morphological complexity, which requires independent control across multiple subcellular compartments up to the level of individual synapses. Here we identify a signaling pathway that regulates the local synthesis of proteins required to form excitatory synapses on parvalbumin-expressing (PV+) interneurons in the mouse cerebral cortex. This process involves regulation of the TSC subunit 2 (Tsc2) by the Erb-B2 receptor tyrosine kinase 4 (ErbB4), which enables local control of mRNA translation in a cell type-specific and synapse type-specific manner. Ribosome-associated mRNA profiling reveals a molecular program of synaptic proteins downstream of ErbB4 signaling required to form excitatory inputs on PV+ interneurons. Thus, specific connections use local protein synthesis to control synapse formation in the nervous system.
2022-11-24 | GSE214258 | GEO
Project description:To systematically explore the dynamics of the synaptic proteome upon neuronal stimulation we employed a simple model system which is based on isolated synaptoeurosomes (SN). Synaptoneurosomes are preparations freshly obtained from the brain and enriched in synapses, containing both pre and postsynaptic compartments. After the isolation they were in vitro stimulated. Protocol was set to induce NMDARs on the synaptoneurosomes which initiate calcium signaling in neurons and lead to long lasting responses such as long term potentiation (LTP). The control experiments in which we incubated SN with RNAse and proteinase K have shown that the translation is taking place inside the SN vesicles. Having established that translation in synaptoeurosomes prepared by us relay on endogenous mRNA we assumed that all proteins which abundance is increased after in vitro stimulation must be locally synthetized on base of mRNA already transported into synapses. In order to identify newly synthetized proteins we in vitro stimulated synaotoneurosomes and combined it with high-resolution quantitative MS techniques (Figure 1A). It is well established that quantitative mass spectrometry heavily depends on physico-chemical properties of peptides and dynamic range (~4 orders of magnitude) of sample which limits a depth of analysis. Some of tryptic peptides would be better detectable unmodified, other when modified for example with stable isobaric labeling techniques iTRAQ or TMT tag. We begin with label-free experiments, but it was mainly limited by dynamic range of protein in SN, we overcome that issue using iTRAQ 8-plex (4 x controls, 4 x stimulation) coupled with sample fractionation prior to LC-MS.. For this reason we used also TMT 10 plex, which allows us to measure 5 control and 5 stimuli samples at once. Using all three techniques we quantified (FDR 0.01) 2187 proteins. Number of identified proteins could be considered as relatively low for shotgun MS experiment. But it should be noticed that synaptical proteome is way different then “normal” cellular proteome since is depleted of nuclear, many of cytoplasmic and other organelles proteins. Finally some of proteins could be heavily modified. . Importantly, we identified 439 of which were significantly (Whitney-Mann p<0.05) upregulated in synaptoneurosomes in response to the stimulation which corresponds to 20% of identified proteins. The average fold change was relatively low which was however expected because it is not possible to quantitatively change a proteome of synapse through short pule of in vitro stimulation. But four replicates are often not enough for reliable statistic calculation of protein level changes. That is because of low level of proteins that could be synthetase at the synapse, due to its low ATP/syntethic potential. Which results in changes on average 3% of protein level.
2020-08-12 | PXD012707 | Pride
Project description:During mononuclear phagocyte system evolution, monocytes differentiate into pro-tumorigenic TAMs. We used single cell RNA sequencing (scRNA-seq) to analyze the characteristics of mononuclear phagocyte in colorectal cancer
2023-07-01 | GSE217774 | GEO
Project description:To systematically explore the dynamics of the synaptic proteome upon neuronal stimulation we employed a simple model system which is based on isolated synaptoeurosomes (SN). Synaptoneurosomes are preparations freshly obtained from the brain and enriched in synapses, containing both pre and postsynaptic compartments. After the isolation they were in vitro stimulated. Protocol was set to induce NMDARs on the synaptoneurosomes which initiate calcium signaling in neurons and lead to long lasting responses such as long term potentiation (LTP). The control experiments in which we incubated SN with RNAse and proteinase K have shown that the translation is taking place inside the SN vesicles. Having established that translation in synaptoeurosomes prepared by us relay on endogenous mRNA we assumed that all proteins which abundance is increased after in vitro stimulation must be locally synthetized on base of mRNA already transported into synapses. In order to identify newly synthetized proteins we in vitro stimulated synaotoneurosomes and combined it with high-resolution quantitative MS techniques (Figure 1A). It is well established that quantitative mass spectrometry heavily depends on physico-chemical properties of peptides and dynamic range (~4 orders of magnitude) of sample which limits a depth of analysis. Some of tryptic peptides would be better detectable unmodified, other when modified for example with stable isobaric labeling techniques iTRAQ or TMT tag. We begin with label-free experiments, but it was mainly limited by dynamic range of protein in SN, we overcome that issue using iTRAQ 8-plex (4 x controls, 4 x stimulation) coupled with sample fractionation prior to LC-MS.. For this reason we used also TMT 10 plex, which allows us to measure 5 control and 5 stimuli samples at once. Using all three techniques we quantified (FDR 0.01) 2187 proteins. Number of identified proteins could be considered as relatively low for shotgun MS experiment. But it should be noticed that synaptical proteome is way different then “normal” cellular proteome since is depleted of nuclear, many of cytoplasmic and other organelles proteins. Finally some of proteins could be heavily modified. . Importantly, we identified 439 of which were significantly (Whitney-Mann p<0.05) upregulated in synaptoneurosomes in response to the stimulation which corresponds to 20% of identified proteins. The average fold change was relatively low which was however expected because it is not possible to quantitatively change a proteome of synapse through short pule of in vitro stimulation. But four replicates are often not enough for reliable statistic calculation of protein level changes. That is because of low level of proteins that could be synthetase at the synapse, due to its low ATP/syntethic potential. Which results in changes on average 3% of protein level.
2020-08-12 | PXD012746 | Pride
Project description:The Moonwalker (Mwk) mouse is a model of dominantly inherited cerebellar ataxia caused by a gain-of-function mutation in the transient receptor potential (TRP) channel TRPC3. We report impairments in dendritic growth and synapse formation early on during Purkinje cell development in the Mwk cerebellum that are accompanied by alterations in calcium signaling.
2015-06-01 | E-MTAB-3517 | biostudies-arrayexpress
Project description:Murine mononuclear phagocyte lineage cells
| PRJNA630056 | ENA
Project description:Mononuclear phagocytes are key regulators of both tissue damage and repair in neuroinflammatory conditions such as multiple sclerosis (MS). To examine divergent phagocyte phenotypes in the inflamed central nervous system (CNS) we introduce an in vivo imaging approach combined with RNAseq and proteomics that allows us to temporally and spatially resolve the evolution of phagocyte polarization in a murine MS model. We show that the initial pro-inflammatory polarization of phagocytes is established after spinal cord entry and critically depends on the compartment they enter. Guided by signals from the CNS environment individual phagocytes then switch their phenotype as lesions move from expansion to resolution. Our study thus provides a first real-time analysis of the temporo-spatial determinants and regulatory principles of phagocyte specification in the inflamed CNS.
2019-07-10 | PXD010245 | Pride