Glialceller

Glialceller are the non-neuronal cells of the nervous system that provide support, protection, and homeostasis for neurons. The term Glialceller is used in some languages for glial cells; in English, they are simply called glial cells or gliocytes.

In the central nervous system, major glial types include astrocytes, oligodendrocytes, and ependymal cells, along with microglia as the resident immune glia. In the peripheral nervous system, Schwann cells and satellite (ganglionic) cells fulfill similar roles. During development, radial glia serve as scaffolds and progenitors for certain CNS glia.

Key functions include structural support, regulation of the extracellular environment, maintenance of ion and neurotransmitter balance, formation of the blood-brain barrier (astrocytic endfeet), myelination of axons (oligodendrocytes in the CNS; Schwann cells in the PNS), and immune defense (microglia).

Glial cells originate from neural progenitors in the CNS; microglia derive from yolk sac macrophages and migrate into the brain. Schwann cells and other peripheral glia arise from neural crest cells.

Dysfunction or transformation of glial cells is linked to disorders such as demyelinating diseases, neuroinflammation, and glial tumors. Ongoing research investigates glia–neuron signaling, astrocyte biology, and glial contributions to synaptic plasticity and neurodegeneration.