Brain-derived neurotrophic factor-transfected and nontransfected 3T3 fibroblasts enhance migratory neuroblasts and functional restoration in mice with intracerebral hemorrhage

Neurogenesis via the activation of endogenous neural progenitor cells is a potential treatment strategy for brain injury, including intracerebral hemorrhage (ICH). We assessed the efficacy of combined cell and brain-derived neurotrophic factor (BDNF) treatment in a mouse model of ICH induced by intracerebral collagenase injection. Complementary DNAs of mouse BDNF were transfected into cell lines of 3T3 fibroblasts. The expression and bioactivity of BDNF were analyzed by immunocytochemistry, Western blot, ELISA, and functional assays. Hematoma area and brain tissue losswere assessed by magnetic resonance imaging. The BDNF-transfected or nontransfected 3T3 fibroblasts were implanted as a growth factor source in mice with ICH. Neurogenesis and functional recovery were evaluated 15 days after ICH. The BDNF-treated mice had the most doublecortin-positive cells near lesions and the least brain tissue loss in all groups. Both cell treatment groups had abundant newly proliferative glial fibrillary acidic protein-positive cells and better functional improvement than controls. These results indicate that fibroblast transplantation, together with recombinant BDNF treatment, after ICH is beneficial in mice. The early functional recovery may result from the growth factors that are provided or evoked by the implanted grafts. These results suggest a potential approach for combining gene and cell therapy for ICH treatment.