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 TBI-induced neuronal apoptosis. (A) Representative confocal images (scale bar, 50 μm) show neuronal apoptosis in hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h after TBI or sham surgery based on TUNEL (green) and DAPI (blue) staining. (B) Bar graph shows the relative percentage of apoptotic neuronal cells in the hippocampus tissues based on TUNEL staining from the four groups of rats at 48 h after TBI or sham surgery. (C) Western blot analysis shows expression levels of CC-3 Bax, and Bcl-2 proteins in the hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h following TBI or Sham surgery. (D–E) Bar graphs illustrate densitometry analyses of (D) CC-3 and (E) Bax/Bcl-2 ratio. The protein bands were normalized to β-actin. (F–G) Bar graphs illustrate qRT-PCR results for the expression levels of (F) CC-3 and (G) Bax/Bcl-2 mRNAs relative to β-actin in hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h after TBI or sham surgery. All data are represented as means ± SEM (n = 5 per group). Statistical significance was determined using one-way ANOVA followed by post-hoc Bonferroni correction. #P ##P *P **P

Figure 6. AS-Exos reduce TBI-induced neuronal apoptosis. (A) Representative confocal images (scale bar, 50 μm) show neuronal apoptosis in hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h after TBI or sham surgery based on TUNEL (green) and DAPI (blue) staining. (B) Bar graph shows the relative percentage of apoptotic neuronal cells in the hippocampus tissues based on TUNEL staining from the four groups of rats at 48 h after TBI or sham surgery. (C) Western blot analysis shows expression levels of CC-3 Bax, and Bcl-2 proteins in the hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h following TBI or Sham surgery. (DE) Bar graphs illustrate densitometry analyses of (D) CC-3 and (E) Bax/Bcl-2 ratio. The protein bands were normalized to β-actin. (FG) Bar graphs illustrate qRT-PCR results for the expression levels of (F) CC-3 and (G) Bax/Bcl-2 mRNAs relative to β-actin in hippocampus tissues from TBI+AS-Exo, Sham, and Sham+AS-Exo groups of rats at 48 h after TBI or sham surgery. All data are represented as means ± SEM (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. Sham group; *P < 0.05 or **P < 0.01 vs. TBI group.