Degradation of perineuronal nets in hippocampal CA2 explains the loss of social cognition memory in Alzheimer's disease
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE317499 | GEO | 2026/01/28
REPOSITORIES: GEO
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| Other | ||||
| GSE317499_counts.csv.gz | Csv |
Items per page: 5 1 - 2 of 2 |
Similar Datasets
Project description:Oligodendrocytes are cells from the central nervous system that can be grouped into precursors, myelin-forming, and non-myelinating perineuronal. The function of perineuronal oligodendrocytes is unknown; it was suggested that they can ensheath denuded axons. We tested this hypothesis. Using cell-specific tags, microarray technology and bioinformatics tools to identify gene expression differences between these subpopulations allowed us to capture the genetic signature of perineuronal oligodendrocytes. Here we report that perineuronal oligodendrocytes are configured for a dual role. As perineuronal, they integrate a repertoire of transcripts designed to create a cell with its own physiological agenda. But they maintain a reservoir of untranslated transcripts encoding the major myelin proteins for â we speculate â a pathological eventuality. We posit that the signature molecules PDGFR-αβ, cytokine PDGF-CC, and the transcription factor Pea3 used â among others - to define the non-myelinating phenotype, may be critical for mounting a myelinating programme during demyelination. Harnessing this capability is of therapeutic value for diseases such as multiple sclerosis. This is the first molecular characterization of perineuronal oligodendrocytes. Experiment Overall Design: Flow Cytometry was used to isolate A2B5/OTMP+ oligodendrocytes from postnatal day 7 rat brain. 4 bioloical replicates were obtained. This data can be compared to the previously submitted oligodendrocyte expression data (GSE5940).
2008-06-18 | E-GEOD-11277 | biostudies-arrayexpress
Project description:Oligodendrocytes are cells from the central nervous system that can be grouped into precursors, myelin-forming, and non-myelinating perineuronal. The function of perineuronal oligodendrocytes is unknown; it was suggested that they can ensheath denuded axons. We tested this hypothesis. Using cell-specific tags, microarray technology and bioinformatics tools to identify gene expression differences between these subpopulations allowed us to capture the genetic signature of perineuronal oligodendrocytes. Here we report that perineuronal oligodendrocytes are configured for a dual role. As perineuronal, they integrate a repertoire of transcripts designed to create a cell with its own physiological agenda. But they maintain a reservoir of untranslated transcripts encoding the major myelin proteins for – we speculate – a pathological eventuality. We posit that the signature molecules PDGFR-αβ, cytokine PDGF-CC, and the transcription factor Pea3 used – among others - to define the non-myelinating phenotype, may be critical for mounting a myelinating programme during demyelination. Harnessing this capability is of therapeutic value for diseases such as multiple sclerosis. This is the first molecular characterization of perineuronal oligodendrocytes. Keywords: developmental
2008-06-01 | GSE11277 | GEO
Project description:Primary cilia are required for the persistence of memory and stabilization of perineuronal nets
| PRJNA728103 | ENA
Project description:Social memory dysfunction is an especially devastating symptom of many neuropsychiatric disorders, which makes understanding the cellular and molecular processes that contribute to such abnormalities important. Evidence suggests that the hippocampus, particularly the CA2 region, plays an important role in social memory. We sought to identify potential mechanisms of social memory dysfunction in the hippocampus by investigating features of neurons, glia, and the extracellular matrix (ECM) of BTBR mice, an inbred mouse strain with deficient social memory. The CA2 is known to receive inputs from dentate gyrus adult-born granule cells (abGCs), neurons known to participate in social memory, so we examined this cell population and found fewer abGCs, as well as fewer axons from abGCs in the CA2 of BTBR mice compared to controls. We also found that BTBR mice had fewer pyramidal cell dendritic spines, in addition to fewer microglia and astrocytes, in the CA2 compared to controls. Along with diminished neuronal and glial elements, we found atypical perineuronal nets (PNNs), specialized ECM structures that regulate plasticity, in the CA2 of BTBR mice. By diminishing PNNs in the CA2 of BTBR mice to control levels, we observed a partial restoration of social memory. Our findings suggest that the CA2 region of BTBR mice exhibits multiple cellular and extracellular abnormalities and identify atypical PNNs as one mechanism producing social memory dysfunction, although the contribution of reduced abGC afferents, pyramidal cell dendritic spine, and glial cell numbers remains unexplored.
| S-EPMC8712624 | biostudies-literature
Project description:The perineuronal net (PNN) region of the brain's extracellular matrix (ECM) surrounds the neural networks within the brain tissue. The PNN is a protective net-like structure regulating neuronal activity such as neurotransmission, charge balance, and action potential generation. Shock-induced damage of this essential component may lead to neuronal cell death and neurodegenerations. The shock generated during a vehicle accident, fall, or improvised device explosion may produce sufficient energy to damage the structure of the PNN. The goal is to investigate the mechanics of the PNN in reaction to shock loading and to understand the mechanical properties of different PNN components such as glycan, GAG, and protein. In this study, we evaluated the mechanical strength of PNN molecules and the interfacial strength between the PNN components. Afterward, we assessed the PNN molecules' damage efficiency under various conditions such as shock speed, preexisting bubble, and boundary conditions. The secondary structure altercation of the protein molecules of the PNN was analyzed to evaluate damage intensity under varying shock speeds. At a higher shock speed, damage intensity is more elevated, and hyaluronan (glycan molecule) is most likely to break at the rigid junction. The primary structure of the protein molecules is least likely to fail. Instead, the molecules' secondary bonds will be altered. Our study suggests that the number of hydrogen bonds during the shock wave propagation is reduced, which leads to the change in protein conformations and damage within the PNN structure. As such, we found a direct connection between shock wave intensity and PNN damage.
| S-EPMC8774183 | biostudies-literature
Project description:Grid cells are part of a widespread network which supports navigation and spatial memory. Stable grid patterns appear late in development, in concert with extracellular matrix aggregates termed perineuronal nets (PNNs) that condense around inhibitory neurons. It has been suggested that PNNs stabilize synaptic connections and long-term memories, but their role in the grid cell network remains elusive. We show that removal of PNNs leads to lower inhibitory spiking activity, and reduces grid cells' ability to create stable representations of a novel environment. Furthermore, in animals with disrupted PNNs, exposure to a novel arena corrupted the spatiotemporal relationships within grid cell modules, and the stored representations of a familiar arena. Finally, we show that PNN removal in entorhinal cortex distorted spatial representations in downstream hippocampal neurons. Together this work suggests that PNNs provide a key stabilizing element for the grid cell network.
| S-EPMC7801665 | biostudies-literature
Project description:We investigate the gene expression changes occurring during the transition of aversive episodic memories from recent to remote. Early mechanisms of memory formation (synaptic consolidation) have been extensively characterized. However, delayed mechanisms (systems consolidation), which maintain hippocampal activity as memories stabilize in cortical circuits, are not well understood. Transcriptomic analysis reveals that, contrary to the transient expression of early- and delayed-response genes, the expression of cytoskeleton- and extracellular matrix- associated genes remains dynamic even at remote time points. The most profound expression changes clustered around primary cilium-associated and collagen genes.
2021-06-05 | GSE174076 | GEO
Project description:A hallmark of schizophrenia pathophysiology is the dysfunction of cortical inhibitory GABA neurons expressing parvalbumin, which are essential for coordinating neuronal synchrony during various sensory and cognitive tasks. The high metabolic requirements of these fast-spiking cells may render them susceptible to redox dysregulation and oxidative stress. Using mice carrying a genetic redox imbalance, we demonstrate that extracellular perineuronal nets, which constitute a specialized polyanionic matrix enwrapping most of these interneurons as they mature, play a critical role in the protection against oxidative stress. These nets limit the effect of genetically impaired antioxidant systems and/or excessive reactive oxygen species produced by severe environmental insults. We observe an inverse relationship between the robustness of the perineuronal nets around parvalbumin cells and the degree of intracellular oxidative stress they display. Enzymatic degradation of the perineuronal nets renders mature parvalbumin cells and fast rhythmic neuronal synchrony more susceptible to oxidative stress. In parallel, parvalbumin cells enwrapped with mature perineuronal nets are better protected than immature parvalbumin cells surrounded by less-condensed perineuronal nets. Although the perineuronal nets act as a protective shield, they are also themselves sensitive to excess oxidative stress. The protection might therefore reflect a balance between the oxidative burden on perineuronal net degradation and the capacity of the system to maintain the nets. Abnormal perineuronal nets, as observed in the postmortem patient brain, may thus underlie the vulnerability and functional impairment of pivotal inhibitory circuits in schizophrenia.
| S-EPMC3670388 | biostudies-other
Project description:Perineuronal nets (PNNs) are specialized complexes of extracellular matrix molecules that surround the somata of fast-spiking neurons throughout the vertebrate brain. PNNs are particularly prevalent throughout the auditory brainstem, which transmits signals with high speed and precision. It is unknown whether PNNs contribute to the fast-spiking ability of the neurons they surround. Whole-cell recordings were made from medial nucleus of the trapezoid body (MNTB) principal neurons in acute brain slices from postnatal day 21 (P21) to P27 mice. PNNs were degraded by incubating slices in chondroitinase ABC (ChABC) and were compared to slices that were treated with a control enzyme (penicillinase). ChABC treatment did not affect the ability of MNTB neurons to fire at up to 1000 Hz when driven by current pulses. However, f-I (frequency-intensity) curves constructed by injecting Gaussian white noise currents superimposed on DC current steps showed that ChABC treatment reduced the gain of spike output. An increase in spike threshold may have contributed to this effect, which is consistent with the observation that spikes in ChABC-treated cells were delayed relative to control-treated cells. In addition, parvalbumin-expressing fast-spiking cortical neurons in >P70 slices that were treated with ChABC also had reduced excitability and gain. The development of PNNs around somata of fast-spiking neurons may be essential for fast and precise sensory transmission and synaptic inhibition in the brain.
| S-EPMC4987413 | biostudies-literature
Project description:Perineuronal nets (PNNs) enwrap mature neurons, playing a role in the control of plasticity and synapse dynamics. PNNs have been shown to have effects on memory formation, retention and extinction in a variety of animal models. It has been proposed that the cavities in PNNs, which contain synapses, can act as a memory store and that they remain stable after events that cause synaptic withdrawal such as anoxia or hibernation. We examine this idea by monitoring place memory before and after synaptic withdrawal caused by acute hibernation-like state (HLS). Animals lacking hippocampal PNNs due to enzymatic digestion by chondroitinase ABC or knockout of the PNN component aggrecan were compared with wild type controls. HLS-induced synapse withdrawal caused a memory deficit, but not to the level of untreated naïve animals and not worsened by PNN attenuation. After HLS, only animals lacking PNNs showed memory restoration or relearning. Absence of PNNs affected the restoration of excitatory synapses on PNN-bearing neurons. The results support a role for hippocampal PNNs in learning, but not in long-term memory storage for correction of deficits.
| S-EPMC9666654 | biostudies-literature