Research Paper Volume 13, Issue 17 pp 21642—21658

Astrocyte-derived exosomes protect hippocampal neurons after traumatic brain injury by suppressing mitochondrial oxidative stress and apoptosis

AS-Exos reduce oxidative stress in hippocampal neurons of TBI-induced murine brains by activating Nrf2 signaling pathway. (A) Western blot analysis and (B) PCR analysis confirms Nrf2 knockdown in Nrf−/− mice. **P +/+ mice. (C) Representative confocal images show DCF fluorescence in the hippocampus tissues from Nrf-KO+Sham, Nrf−-KO+TBI, Nrf+/++Sham, and Nrf+/++TBI mice injected with or without AS-Exos. (D) Bar graphs illustrate relative DCF fluorescence in the hippocampus tissues from the mice groups. (E) Amplex red hydrogen peroxide/peroxidase assay results show the release of mitochondrial H2O2. Mitochondria were isolated from the hippocampus tissues of the mice groups. (F) SOD activity, (G) CAT activity and (H) Reduced GSH levels in the hippocampus tissues from the mice groups. Data are represented as means ± SD (n = 5 per group). Statistical significance was determined using one-way ANOVA followed by post-hoc Bonferroni correction. #P ##P *P **P +/++TBI group; &P &&P

Figure 7. AS-Exos reduce oxidative stress in hippocampal neurons of TBI-induced murine brains by activating Nrf2 signaling pathway. (A) Western blot analysis and (B) PCR analysis confirms Nrf2 knockdown in Nrf−/− mice. **P < 0.01 vs. Nrf2+/+ mice. (C) Representative confocal images show DCF fluorescence in the hippocampus tissues from Nrf-KO+Sham, Nrf-KO+TBI, Nrf+/++Sham, and Nrf+/++TBI mice injected with or without AS-Exos. (D) Bar graphs illustrate relative DCF fluorescence in the hippocampus tissues from the mice groups. (E) Amplex red hydrogen peroxide/peroxidase assay results show the release of mitochondrial H2O2. Mitochondria were isolated from the hippocampus tissues of the mice groups. (F) SOD activity, (G) CAT activity and (H) Reduced GSH levels in the hippocampus tissues from the mice groups. Data are represented as means ± SD (n = 5 per group). Statistical significance was determined using one-way ANOVA followed by post-hoc Bonferroni correction. #P < 0.05 or ##P < 0.01 vs. C57BL/6+Sham; *P < 0.05 or **P < 0.01 vs. and Nrf+/++TBI group; &P < 0.05 or &&P < 0.01 vs. Nrf2-KO+Sham group.