Fig. 6
From: Impact of gulf war toxic exposures after mild traumatic brain injury
Evaluation of the extent of white matter integrity at 6 months after injury in the corpus callosum. a–d Luxol fast blue/cresyl violet (LFB/CV) staining indicated changes in white matter integrity with a thinning of the corpus callosum (CC) by approximately 15% in the GW treated group, 40% in the r-mTBI group and 35% in the r-TBI/GW group (P < 0.0001) when to compared to Sham/V. aa Quantitative analysis of the thickness of the corpus callosum. (*P < 0.05, Two-Way ANOVA-followed by Tukey post hoc comparisons). A three-Way ANOVA analysis revealed a Sex and Injury effect: F(1, 56) = 13.58 P=0.0005; F(1, 56) = 87.58, P < 0.0001; but not Treatment effect F(1, 56) = 0.68, P = 0.41. e, h Granular axonal profiles stained positively with the axonal injury marker (amyloid precursor protein [APP]) were predominantly seen in both r-mTBI groups within the CC when compared to their respective sham control. bb The density of APP-immunoreactive profiles per unit area in the body of the CC of the r-mTBI/GW group was greater than in the r-mTBI/V group (r-mTBI/V, 10.25 ± 1.0 vs r-mTBI/GW, 20.44 ± 2.3 axonal profiles/body of CC, P < 0.0001; Data are presented as mean ± standard error of the mean). Magnification of the boxed inset represents the area indicated by the arrow. A three-Way ANOVA analysis revealed no Sex effect F(1, 56) = 2.6, P = 0.1, an Injury effect: F(1, 56) = 290.3 P < 0.0001 and a Treatment effect; F(1, 56) = 52.16 P < 0.0001. i, l The number of Oligodendrocytes cells was counted using the Oligo2 pan marker, a transcription factor that is expressed in both mature oligodendrocytes as well as oligodendrocyte precursor cells. bb At 6 months post injury an increase of the number of Oligo2+ cells were observed in the GW group with 35.7 cells per 200 µm2, followed by the r-mTBI group with 41.7 cells per 200 µm2 while the r-mTBI/GW group showed the highest number of positive cells 58.1 cells per 200 µm2 (P < 0.0001, Two-Way ANOVA-followed by Tukey post hoc comparisons). A three-Way ANOVA analysis revealed no Sex effect F(1, 67) = 0.13, P = 0.7, an Injury effect: F(1, 67) = 208.0 P < 0.0001 and a Treatment effect; F(1, 56) = 90.88, P < 0.0001. m–p Strong reactive astrogliosis was observed in the body of the CC in both r-mTBI groups when compared to the r-sham group while no difference was observed between the sham/V and the sham/GW. dd Quantitative analysis of glial fibrillary acidic protein (GFAP) staining in the body of the CC (Sham/V, 4.9 ± 0.3% vs Sham/GW, 8.4 ± 2.5%; P > 0.05; r-mTBI/V 13.3 ± 5.0% vs r-mTBI/GW, 24.6 ± 7.0%; P < 0.0001). A three-Way ANOVA analysis revealed a Sex effect F(1, 67) = 0.13 P < 0.0001, an Injury effect: F(1, 67) = 208.0 P < 0.0001 and a Treatment effect; F(1, 56) = 90.88 P < 0.0001. q–t Iba-1 immunostaining showed moderate immunoreactivity in both TBI while no difference was observed between the Sham/V and the Sham/GW. ee Quantitative analysis of Iba-1 staining in the body of the CC (Sham/V, 1.54 ± 1.0% vs Sham/GWI, 1.79 ± 0.8%; P > 0.05; TBI/V 5.3 ± 1.5% vs r-mTBI/GW, 7.6 ± 1.4%; P=0.019). A three-Way ANOVA analysis revealed a Sex effect F(1, 79) = 24.66 P < 0.0001, an Injury effect: F(1, 79) = 98.5 P < 0.0001 and a Treatment effect; F(1, 79) = 7.06 P=0.0095. u–y A second immunostaining with cluster of differentiation receptors 45 (CD45) probed for activated microglia and peripherical macrophage. ff Quantitative analysis of CD45 staining in the body of the CC (Sham/V, 0.97 ± 0.2 vs Sham/GW, 2.9 ± 0.49%; P > 0.05; r-mTBI/V 3.7 ± 0.07% vs r-mTBI/GW, 5.9 ± 0.12%; P = 0.042). A three-Way ANOVA analysis revealed no Sex effect F(1, 64) = 0.32, P > 0.05, an Injury effect: F(1, 64) = 23.97 P < 0.0001 and a Treatment effect; F(1, 79) = 12.44, P = 0.008. Tissue sections were counterstained with hematoxylin. Data are presented as Whiskers: Min to Max. Show all points; symbol represents 1 mouse N = 8/12 per group per Sex)