Astrocytes in functional recovery following central nervous system injuries

Astrocytes are increasingly recognised as partaking in complex homeostatic mechanisms critical for regulating neuronal plasticity following central nervous system (CNS) insults. Ischaemic stroke and traumatic brain injury are associated with high rates of disability and mortality. Depending on the context and type of injury, reactive astrocytes respond with diverse morphological, proliferative and functional changes collectively known as astrogliosis, which results in both pathogenic and protective effects. There is a large body of research on the negative consequences of astrogliosis following brain injuries. There is also growing interest in how astrogliosis might in some contexts be protective and help to limit the spread of the injury. However, little is known about how astrocytes contribute to the chronic functional recovery phase following traumatic and ischaemic brain insults. In this review, we explore the protective functions of astrocytes in various aspects of secondary brain injury such as oedema, inflammation and blood-brain barrier dysfunction. We also discuss the current knowledge on astrocyte contribution to tissue regeneration, including angiogenesis, neurogenesis, synaptogenesis, dendrogenesis and axogenesis. Finally, we discuss diverse astrocyte-related factors that, if selectively targeted, could form the basis of astrocyte-targeted therapeutic strategies to better address currently untreatable CNS disorders.image Abstract figure legend The roles of astrocytes in CNS injuries.image

Automated summary

Astrocytes play a crucial role in regulating neuronal plasticity after central nervous system (CNS) injuries, with both pathogenic and protective effects. While there is extensive research on the negative consequences of astrocyte proliferation following brain injuries, there is a growing interest in exploring the potential protective functions of astrocytes and their contribution to chronic functional recovery. This review discusses the protective functions of astrocytes in aspects such as edema, inflammation, and blood-brain barrier dysfunction, as well as their role in tissue regeneration.