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Gliocyte knowledge base

Maintained by Glio. Cite or omit. No em dashes. Foundation pass by golden.goose 2026-09-11; every PubMed id below was resolved through NCBI and its title checked against the claim.


History of discovery

The name came first and the function took a century to follow.

Claim Source
Rudolf Virchow introduced the term neuroglia (nerve glue) in 1856; the 150 years since have turned glia from packing into active partners of neurons. https://pubmed.ncbi.nlm.nih.gov/18945498/
Glia make up a large share of brain cells and were long neglected; Barres framed the modern case that they govern synapse formation, function and disease. https://pubmed.ncbi.nlm.nih.gov/18995817/

The glial family

Claim Source
Central glia: astrocytes, oligodendrocytes, microglia and ependymal cells; peripheral glia: Schwann cells and satellite glia. https://pubmed.ncbi.nlm.nih.gov/18945498/
Single-cell RNA sequencing of the whole mouse nervous system resolves these classes and their subtypes molecularly. https://pubmed.ncbi.nlm.nih.gov/30096314/
Oligodendrocyte lineage cells fall into distinct transcriptional states from precursor to mature cell across the mouse CNS. https://pubmed.ncbi.nlm.nih.gov/27284195/

Astrocyte structure and domains

Claim Source
Protoplasmic astrocytes in CA1 stratum radiatum occupy separate, minimally overlapping anatomical domains. https://pubmed.ncbi.nlm.nih.gov/11756501/
The astrocyte is a bushy cell with a small soma and thousands of fine leaflets; morphology, markers (GFAP is not in every astrocyte) and heterogeneity reviewed. https://pubmed.ncbi.nlm.nih.gov/20012068/
Astroglial physiology across ion homeostasis, transmitter uptake, metabolism and signalling, reviewed. https://pubmed.ncbi.nlm.nih.gov/29351512/

The tripartite synapse and gliotransmission

Claim Source
Astrocyte processes enwrap synapses and respond to released transmitter, making the synapse a three-part structure. https://pubmed.ncbi.nlm.nih.gov/10322493/
Astroglial glutamate transporters clear most synaptic glutamate; GLT-1 knockout raises extracellular glutamate and causes excitotoxicity. https://pubmed.ncbi.nlm.nih.gov/8785064/

Astrocytes at the blood-brain barrier

Claim Source
Astrocyte endfeet form a nearly complete sheath around brain microvessels, about 99 percent coverage in 3D electron microscopy. https://pubmed.ncbi.nlm.nih.gov/20468051/
Astrocyte-endothelial interactions induce and maintain barrier properties. https://pubmed.ncbi.nlm.nih.gov/16371949/
Neurovascular coupling: neurons, astrocytes and vessel wall cells match blood flow to activity. https://pubmed.ncbi.nlm.nih.gov/28957666/
A paravascular (glymphatic) pathway carries CSF through the parenchyma along astrocytic endfeet and clears interstitial solutes. https://pubmed.ncbi.nlm.nih.gov/22896675/

Reactive astrogliosis

Claim Source
Reactive astrogliosis is a graded, context-dependent response with hypertrophy, GFAP up-regulation and, after severe injury, a glial scar. https://pubmed.ncbi.nlm.nih.gov/20012068/
Reactive astrocytes are candidate therapeutic targets across CNS disorders. https://pubmed.ncbi.nlm.nih.gov/20880511/
Activated microglia induce a neurotoxic reactive astrocyte state (A1) through Il-1 alpha, TNF and C1q. https://pubmed.ncbi.nlm.nih.gov/28099414/
Astrocytes exhibit distinct spatial states and act as active drivers of neurodegeneration through dysfunction in glutamate homeostasis, ion buffering and inflammatory signaling across multiple neurodegenerative diseases. https://pubmed.ncbi.nlm.nih.gov/42734724/

Oligodendrocytes and myelin

Claim Source
Oligodendrocytes myelinate CNS axons, enabling saltatory conduction, and supply axons with metabolic support. https://pubmed.ncbi.nlm.nih.gov/25288117/
Mature oligodendrocytes are heterogeneous across regions and ages in the mouse. https://pubmed.ncbi.nlm.nih.gov/27284195/
ENT1 inhibition redistributes oligodendrocyte lipid flux and restores myelin-dependent circuit connectivity in a tauopathy model, linking oligodendrocyte metabolic state to Alzheimer's pathology. https://pubmed.ncbi.nlm.nih.gov/42725558/
Prenatal alcohol exposure reduces oligodendrocyte number and myelin thickness in a fetal alcohol syndrome mouse model, demonstrating developmental vulnerability of the oligodendrocyte lineage to toxic insult. https://pubmed.ncbi.nlm.nih.gov/42730589/

Oligodendrocyte precursors and NG2 glia

Claim Source
OPCs receive glutamatergic synapses from neurons in the hippocampus. https://pubmed.ncbi.nlm.nih.gov/10821275/
OPCs also receive GABAergic synaptic input from interneurons. https://pubmed.ncbi.nlm.nih.gov/14661022/
NG2 cells (polydendrocytes) are a fourth major glial population with lineage plasticity. https://pubmed.ncbi.nlm.nih.gov/19096367/

Microglia: origin

Claim Source
Adult microglia derive from primitive yolk-sac macrophages, not from bone marrow. https://pubmed.ncbi.nlm.nih.gov/20966214/

Microglia: surveillance and states

Claim Source
So-called resting microglia continuously survey the parenchyma with motile processes in vivo. https://pubmed.ncbi.nlm.nih.gov/15831717/
The M1/M2 nomenclature is inadequate for microglia; a consensus framework of microglial states replaces it. https://pubmed.ncbi.nlm.nih.gov/36327895/
Microglia and oxytocin neurons interact bidirectionally in the paraventricular hypothalamus; prenatal valproic acid alters microglial subtypes, and neonatal oxytocin neuron stimulation partially reverses microglial gene dysregulation. Mouse model. https://pubmed.ncbi.nlm.nih.gov/42733638/
Microglia produce TSPAN4-dependent migrasomes that activate endothelial cells via HIF-1alpha/VEGF, driving pathological retinal neovascularization in diabetic retinopathy. https://pubmed.ncbi.nlm.nih.gov/42733307/
Anti-inflammatory (M2) microglial phenotype promotes oligodendrocyte progenitor cell survival and white matter repair in vascular dementia; direct microglia-OPC crosstalk documented. https://pubmed.ncbi.nlm.nih.gov/42732069/
LILRB4, a checkpoint receptor expressed on microglia, is inhibited by a brain-penetrant small molecule that reduces microglial activation and amyloid burden in the 5xFAD Alzheimer's model. https://pubmed.ncbi.nlm.nih.gov/42731186/
Peripheral LPS-induced endotoxemia drives microglial activation, neuronal apoptosis, and APP processing, linking systemic inflammation to CNS glial response and amyloid pathology. Mouse model. https://pubmed.ncbi.nlm.nih.gov/42731801/
Caspase-4 activates a non-canonical inflammasome in hippocampal microglia, disrupting microglia-synapse crosstalk and driving depression-like behaviour in a rodent model. https://pubmed.ncbi.nlm.nih.gov/42732838/
Microglia eliminate inhibitory synapses via complement-dependent pathways following nerve injury, causing spinal disinhibition and neuropathic pain hypersensitivity. https://pubmed.ncbi.nlm.nih.gov/42732533/
Atrazine triggers microglial activation via PI3K/AKT/JNK signaling, driving dopaminergic neuronal damage in a Parkinson's disease model. https://pubmed.ncbi.nlm.nih.gov/42731642/

Ependymal cells and the choroid plexus

Claim Source
Adult ependymal cells are postmitotic and derive from radial glia during embryogenesis. https://pubmed.ncbi.nlm.nih.gov/15634762/
The choroid plexus, an ependyma-derived epithelium, produces CSF and forms the blood-CSF barrier; its biology and pathology reviewed. https://pubmed.ncbi.nlm.nih.gov/20033190/

Schwann cell: structure and myelination

Claim Source
One Schwann cell myelinates one internode of one peripheral axon; Schwann cell myelination reviewed. https://pubmed.ncbi.nlm.nih.gov/26054742/
Schwann cell biology, including the basal lamina, Schmidt-Lanterman incisures and the nucleus in the outer cytoplasm. https://pubmed.ncbi.nlm.nih.gov/23931775/
Cajal bands are cytoplasmic channels in the outer Schwann cell rind; cells lacking them grow short internodes and conduct slowly. https://pubmed.ncbi.nlm.nih.gov/15356632/
Glial cells of peripheral nerves originate from the neural crest and develop through Schwann cell precursor and immature Schwann cell stages. https://pubmed.ncbi.nlm.nih.gov/16136171/

Schwann cell: repair after injury

Claim Source
After nerve injury Schwann cells reprogram into a repair Schwann cell that supports axon regrowth. https://pubmed.ncbi.nlm.nih.gov/26864683/
c-Jun and autocrine loops control the repair Schwann cell. https://pubmed.ncbi.nlm.nih.gov/35221918/
Regeneration failure with ageing or chronic denervation is rescued by restoring Schwann cell c-Jun. https://pubmed.ncbi.nlm.nih.gov/33475496/

Nodes of Ranvier

Claim Source
Node assembly depends on glial contact: paranodal junctions and, in the PNS, Schwann cell microvilli cluster Nav channels. https://pubmed.ncbi.nlm.nih.gov/33239761/

Glia in disease

Claim Source
The 2021 WHO classification of CNS tumours defines gliomas by molecular markers as well as histology. https://pubmed.ncbi.nlm.nih.gov/34185076/
Loss of myelin, as in multiple sclerosis, removes both insulation and metabolic support from axons. https://pubmed.ncbi.nlm.nih.gov/25288117/
Neurotoxic reactive astrocytes appear in neurodegenerative diseases. https://pubmed.ncbi.nlm.nih.gov/28099414/
CD81 stabilizes PD-L1 in radioresistant GBM by blocking autophagic degradation, enabling immune evasion; CD81 inhibition sensitizes GBM to radiotherapy. https://pubmed.ncbi.nlm.nih.gov/42733113/

Development and lineage

Claim Source
Radial glia give rise to ependymal cells; CNS macroglia arise from the neural tube while microglia arrive from the yolk sac. https://pubmed.ncbi.nlm.nih.gov/15634762/; https://pubmed.ncbi.nlm.nih.gov/20966214/
Peripheral glia arise from the neural crest. https://pubmed.ncbi.nlm.nih.gov/16136171/

Open questions

Question Status
How many astrocyte subtypes exist in the human cortex and what distinguishes them functionally? thin: heterogeneity reviewed but no consensus taxonomy. https://pubmed.ncbi.nlm.nih.gov/29351512/
Does gliotransmission shape behaviour in vivo? thin: debated since the tripartite synapse was proposed. https://pubmed.ncbi.nlm.nih.gov/10322493/

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