[Abstract Title]. - Society for Neuroscience

National Multiple Sclerosis Society, Grant RG3712A1 (V.G.)
Title: Hyperoxia causes astrogliosis in the developing brain
Authors: *T. SCHMITZ, L.-J. CHEW, V. GALLO;
Ctr. for Neurosci. Res., Children's Natl. Med. Ctr., Washington, DC
Abstract: Periventricular white matter damage is a major cause of impaired neurological
development in premature infants. Contributing factors include perinatal infection, inflammation
and hypoxia/ischemia. High oxygen (80%) concentrations have also been shown to cause
oligodendrocyte progenitor cell death and hypomyelination. In many animal models of perinatal
brain damage, the observation of astrocyte activation (astrogliosis) has often been associated
with CNS inflammation and white matter deficiency. The role of astroglial changes in white
matter loss following oxygen exposure however has not been explored and is the focus of this
study. We investigated the effects of high oxygen concentrations on astrocytes both in vivo and
in vitro. In a transgenic mouse line bearing astrocyte-targeted reporter expression (glial fibrillary
acidic protein promoter, GFAP-EGFP), exposure of postnatal day 6 (P6) pups to 48h hyperoxia
decreased myelin basic protein (MBP) expression in subcortical white matter regions when
analyzed by immunocytochemistry and Western blotting after a 4-day recovery in room air at
P12. These observations at P12 were associated with markedly elevated GFAP-EGFP and GFAP
expression levels (P