FIG. 3.

Anti-apoptotic and blood–brain barrier (BBB) protective effects of Wnt3a/β-catenin signaling in vitro and after TBI in vivo. (A) Primary neuronal cultures were dissected from E16 mice and then plated until day 12 in vitro (12 DIV). Groups exposed to oxygen-glucose deprivation (OGD), concurrently with either Wnt3a administration or phosphate-buffered saline (PBS) vehicle control administration. Western blot evaluation of salient protein levels were performed. (B) Quantification of normalized intensity of β-catenin. (C) Levels of cell death as measured by LDH release after OGD, and cultures were treated with either just Wnt3a, Wnt3a + Wnt pathway inhibitor, XAV939, non-targeting (NT)-siRNA, β-catenin siRNA, or β-catenin + Wnt3a. *p < 0.05, compared with Control group. p < 0.05, compared with β-catenin siRNA group. Δp < 0.05, compared with Wnt3a-only group. (D-H) Mice were sacrificed at 2 days post-TBI after having been given two intranasal injections of either saline or Wnt. (D) Representative immunoblots for markers related to cell death and BBB disruption. All immunoblots were normalized to the β-actin control, and then to Sham within group. (E) Quantification of the normalized intensity of cleaved caspase-3. (F) Quantification of the normalized intensity of Bcl-2. (G) Quantification of the normalized intensity of matrix metalloproteinases 9 (MMP-9). (H) Quantification of the normalized intensity of MMP-2. *p < 0.05, compared with Sham. #p < 0.05, compared with TBI+Saline. n = 3 for Sham group, n = 7 for both TBI+Saline and TBI+Wnt3a groups.