Microglia-mediated neuroinflammation in traumatic brain injury: a review

Traumatic brain injury (TBI) is a leading cause of disability worldwide, characterized by a complex interplay of primary and secondary injury mechanisms. Microglia, the resident immune cells of the central nervous system, play a crucial role in the inflammatory response following TBI. To review the current understanding of microglia-mediated neuroinflammation in TBI, exploring its dual nature as a protective and detrimental process. A comprehensive literature review was conducted using databases such as PubMed, Scopus, and Google Scholar. Relevant studies investigating the role of microglia in TBI were included. In the early stages of TBI, microglia exhibit a protective response, releasing cytokines and chemokines to promote neuronal survival and tissue repair. However, prolonged or excessive microglial activation can lead to neurotoxicity and exacerbate secondary injury. Microglia-mediated neuroinflammation involves complex signaling pathways, including Toll-like receptors, purinergic receptors, and the complement system. Microglia-mediated neuroinflammation in TBI is a double-edged sword. While acute microglial activation can promote repair, chronic or excessive inflammation contributes to neuronal damage and functional deficits. Understanding the temporal and molecular dynamics of microglial responses is crucial for developing therapeutic strategies to modulate neuroinflammation and improve outcomes after TBI.