BDNF and Stroke: In this respect, treatment intended to rescue these expression levels may circumvent the TBI‐induced apoptosis in the peri‐impact area.55, 56 While preclinical studies of stroke have revealed that administering stand‐alone glial cell line–derived neurotrophic factor (GDNF),57 brain‐derived neurotrophic factor (BDNF),58 vascular endothelial growth factor (VEGF),56 stem cell factor (SCF),59 or stromal cell–derived factor (SDF)‐1α60 may produce improvements on neurological outcomes, various complications limit the likelihood of clinical success.