BDNF and brain ischemia: After cerebral ischemia, the increased expression of brain-derived neurotrophic factor (BDNF), platelet-derived growth factor-B (PDGF-B), transforming growth factor-beta (TGF-β), fibroblast growth factor 2 (FGF2), and VEGF, may promote both angiogenesis and axonal outgrowth (Hatakeyama et al., 2020).