reactive gliosis

Definition

Target type: biologicalprocess

A neuroinflammatory response, occurring over several days, during which glial cells undergo nonspecific reactive changes in response to damage to the central nervous system (CNS); typically involves the proliferation or hypertrophy of different types of glial cells. [GOC:aruk, GOC:bc, PMID:24462092]

Reactive gliosis is a complex biological process that occurs in the central nervous system (CNS) in response to injury, infection, or inflammation. It involves the activation and proliferation of glial cells, primarily astrocytes and microglia, leading to the formation of a glial scar. The process can be broadly divided into three stages:

1. **Initial Response:** Following injury or insult, microglia, the resident immune cells of the CNS, are the first responders. They become activated, migrating to the site of injury and releasing various inflammatory mediators, such as cytokines and chemokines. These mediators initiate the recruitment of other immune cells, including macrophages, neutrophils, and lymphocytes, to the site of injury.

2. **Astrocyte Activation and Proliferation:** Astrocytes, the most abundant glial cell type in the CNS, are also activated in response to injury. They undergo a process known as astrogliosis, characterized by hypertrophy, hyperplasia, and the upregulation of various genes, including those involved in glial fibrillary acidic protein (GFAP) expression. These activated astrocytes, known as reactive astrocytes, form a dense network around the site of injury, creating a glial scar.

3. **Glial Scar Formation:** The glial scar, composed primarily of reactive astrocytes, serves multiple functions. It helps to contain the damaged area, limiting the spread of inflammation and damage to surrounding tissues. It also contributes to the restoration of tissue homeostasis by removing debris and promoting tissue repair. However, the glial scar can also impede axonal regeneration and hinder functional recovery.

Reactive gliosis is a double-edged sword. While it is essential for protecting the CNS from further damage, it can also contribute to the progression of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. Understanding the complex mechanisms underlying reactive gliosis is crucial for developing therapeutic strategies to promote neuroprotection and enhance functional recovery after CNS injury.'
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Proteins (2)

Compounds (23)