BDNF and brain infarction: In the early stage of cerebral infarction, MSC have a stimulating effect on the expression of various growth factors in the ischemic zone, namely, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), basic fibroblast growth factor (bFGF), IGF, HGF, VEGF, angiogenic factor, and stem cell factor.