GRN and frontotemporal dementia: Together, our results imply that PGRN deficiency seems to increase astrocyte activity and expression in the NAc, as well as dysfunction in inflammatory cytokine production, under normal circumstances, thus being involved in FTD-like behaviors; however, PGRN deficiency attenuates NAc neuroinflammatory reactions under acute immune challenge, thus resulting in the antidepressant effects in the NAc neuroinflammation-related depressive-like phenotype.