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Astrocytes react to central nervous system injury and participate in gliotic responses,imparting both negative and positive effects on axonal regeneration.Despite the considerable biochemical and morphological changes,insult to astrocytes,and known influence of steroids on glial activation,details concerning glucocorticoid receptor expression and activity remain unknown.Such mechanistic information is essential for advancing and improving therapies for the treatment of central nervous system injuries.Using an in vilro wound-healing assay,we found that glucocorticoid receptor p (GRP),but not GRa,was upregulated and acted as a regulator of gliosis after injury.In addition,our results suggest that GRp interacts with P-catenin and is a necessary component for proliferation and migration of astrocytes in both injury and glioma.Further analysis indicates that GRβ/β-catenin interactions are a key modulator of astrocyte reactivity via sustained Wnt/β-catenin/ TCF signaling as part of their dominant-negative effect on GSK-3β-independent GRα-mediated trans-repression.These findings expand our knowledge of the mechanism of GRβ promotion of astrocyte proliferation and migration following injury and in glioma.This information also furthers our understanding of the function of glucocorticoid receptors in central nervous system injury and disease,as well as in the basic biochemical responses that astrocytes undergo in response to injury and glioma pathogenesis.