Fig. 4

High expression of FOXO1 in neutrophils reduces the incidence of depression after TBI. FOXO1^△Lyz2 mice and their WT littermate were randomly divided into a sham group and a TBI group. a Body weight and behavioral tests, including the sucrose preference and TST in mice, n = 30 in the sham group, n = 100 in WT TBI mice, n = 30 in FOXO1^△Lyz2 sham mice, and n = 30 in FOXO1^△Lyz2 TBI mice. b The behavioral tests of sucrose preference and TST were assayed in WT TBI mice for the identification of depression after TBI. Sham group, n = 15; TBI with depression group, n = 37; TBI without depression group, n = 55. c The behavioral tests of sucrose preference and TST were assayed in FOXO1^△Lyz2 TBI mice for the identification of depression after TBI. Sham group, n = 15; TBI with depression group, n = 6; TBI without depression group, n = 22. d Immunostaining of fibrinogen (green) and CD31 (red) in the brain tissue of TBI mice (scale bar = 20 μm). e Immunostaining of FOXO1 (red), LY6G (green), and nuclei (DAPI, blue) in brain injury tissue of the TBI mouse model (scale bar = 20 μm). In d and e, in each group, n = 5 for data collection. Data are represented as the mean ± SEM. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, ns non-significant. FOXO1 forkhead box protein O1, TBI traumatic brain injury, WT wild-type, TST tail suspension test, DAPI 4,6-diamidino-2-phenylindole dihydrochloride