FGF-2 controls neurogenesis in the adult hippocampus after brain injury
October 1, 2003
Unlike other organs, the brain had been assumed to have a limited ability to repair itself, but recent evidence suggests that brain is a more dynamic, plastic organ than originally appreciated and is endowed with the potential for repair and regeneration. Despite this observation, the molecular signals that control neurogenesis—the generation of new neurons—in the adult brain have been unclear. In the October 15 Journal of Clinical Investigation, Shinichi Yoshimura and colleagues from Harvard Medical School show that fibroblast growth factor-2 (FGF-2) regulates neurogenesis and degeneration in the dentate gyrus following traumatic brain injury (Journal of Clinical Investigation, 112:1202-1210, October 15, 2003).
Yoshimura et al. used FGF-2–/– mice and observed that in these animals, following a controlled cortical impact, BrdU marked positive cells and BrdU-positive neurons numbered fewer in the dentate gyrus compared with FGF-2+/+ mice. In FGF-2–/– mice, there was also a greater decrease in the volume of the granule cell layer (GCL) and the number of GCL neurons following traumatic brain injury. In addition, the authors showed that overexpression of FGF-2 significantly increased the numbers of dividing cells and BrdU-positive neurons and decreased the volume of GCL.
“FGF-2 is, at least in part, responsible for regulating neuronal replacement, as well as attenuating neuronal loss after traumatic brain injury. FGF-2 supplementation may provide a rational strategy to treat brain injury by simultaneously enhancing neurogenesis and reducing neurodegeneration,” conclude the authors.
“[This] demonstrates that neurogenesis is not simply a cell-autonomous property of resident stem cells but is determined by the environmental milieu,” suggest Anna F. Hallbergson and colleagues from the Chicago Medical School in an accompanying spotlight editorial.
Links for this article
P. Bach-y-Rita, “Theoretical basis for brain plasticity after a TBI,”
Brain Injury, 17:643-651, August 2003.
S. Yoshimura et al., “FGF-2 regulates neurogenesis and degeneration
in the dentate gyrus after traumatic brain injury in mice,” Journal of
Clinical Investigation, 112:1202-1210, October 15, 2003.
Harvard Medical School
Chicago Medical School
A.F. Hallbergson et al., “Neurogenesis and brain injury: Managing a
renewable resource for repair,” Journal of Clinical Investigation, 112:1128-1133,
October 15, 2003.
Copyright © 2003, The Scientist Inc.