BDNF and stroke disorder: Transplantation of gene-modified stem cells overexpressing various growth factors or cytokines, such as BDNF, GDNF, NGF, VEGF, hepatocyte growth factor (HGF), placental growth factor (PIGF), angiopoietin-1 (ANG-1), erythropoietin (EPO), IL-10, and Noggin has been demonstrated to significantly promote functional recovery compared to stem cells alone in experimental stroke models.