Diversity Supplement for Erica Littlejohn: Preclinical evaluation of IGF1 therapy for traumatic brain injury

The fellow has expressed a strong interest in exploring therapies that enhance the endogenous repair capabilities of the damaged brain. Contusional brain injury results in damage to cortical and hippocampal neurons and is accompanied by both motor and cognitive behavioral dysfunction. It is encouraging that brain injury also stimulates certain aspects of neurogenesis in the hippocampal subgranualar zone (SGZ) and the subventricular zone (SVZ). However, endogenous neurogenesis is minimally effective at mitigating trauma-induced neuron loss and behavioral dysfunction. Therefore, the fellow has selected a project within the parent proposal which is focused on evaluating the effects of IGF-1 administration on posttraumatic neurogenesis. To this end, she will test the hypothesis that IGF-1 increases progenitor cell proliferation and commitment to a neuronal fate by using cell-type specific markers and markers of cell proliferation to quantify the birth of new neurons in the SGZ and SVZ after contusion brain injury in mice receiving either recombinant human IGF-1 (rhIGF-1) or vehicle. Erica will then test the proliferating celles in the first week after TBI and then identifying their phenotype at 1 mont after injury. She will also map the mirgration of immature neurons fromt he SVZ to the contusion site to determine whether IGF-1 promotes increased migration of immature neurons to brain lesions. In addition, mice will be subjected to repeated cognitive testing to evaluate any correlation between increased neurogenesis and improved memory function after TBI. Experimentally, the fellow will receive training in small animal anethesia, surgery, injury and postoperative care, as well as tissue harvesting, tissue cutting, histology and immunohistochemistry. The fellow will also learn light, epifluorescence and confocal microscopy, image analysis, behavioral testing, data analysis, and statistical analysis.