D.  Freedman,N.  Nived,B.  Decker,S.  Narla,S.  Shafik,S.  Manohar,R.  Salvi,Michal K. Stachowiak,E.K.  Stachowiak,
Neurogenesis and Oligodendrogenesis in a Mouse Model of Blast-Induced Traumatic Brain Injury
Neurology and Neurobiology
2020
2613-7828
http://dx.doi.org/10.31487/j.NNB.2020.03.07
https://www.sciencerepository.org/neurogenesis-and-oligodendrogenesis-in-a-mouse-model-of-blast-induced_NNB-2020-3-107 
Abstract: Neurological manifestations of blast-induced Post Traumatic Stress Disorder (PTSD) extend long after the
initial injury indicating lasting changes in brain function. In this study, we characterized brain injury,
changes in neurogenesis and oligodendrogenesis in an adult murine blast model following a short (5 days)
and long (21 days) post-blast recovery. Acoustic blasts led to an initial, activation of microglia and
astrogliosis and a widespread cortical and subcortical apoptosis. The loss of myelinated cortical axons at 5
days was followed by the reappearance of abnormal misdirected fibers at 21 days. At 21 days post-blast, we
observed increases in doublecortin-positive (DCX+
) neuroblasts in the subventricular zone (SVZ) and
hippocampal subgranular zone (SGZ) indicating increased neurogenesis. No changes in DCX+
cells were
found in the brain cortex. In the cortex, the early disappearance of myelinated neuronal fibers was
accompanied by a loss of O4+ oligodendrocytes and their Ki67-expreasing (Ki67+
) oligodendrocyte
precursor cells (OPC). However, at 5 days we observed a robust appearance of cells expressing Olig2 (O2+
),
an early determinant of oligodendrocyte lineage. At 21 days post-blast, the population of OPC increased
and the mature O4+ oligodendrocytes were restored to control levels. In contrast, in the SVZ and SGZ, O4+
cells were not affected by the blast suggesting a local cortical origin for cortical oligodendrogenesis. These
results suggest that blast-induced activation of SVZ and SGZ neurogenesis and cortical oligodendrogenesis
could have long-lasting impact on brain function including memory disorders observed in both animal
models and human’s PTSD.Keywords: Blast induced traumatic brain injury, traumatic brain injury, neurogenesis, oligodendrogenesis