[Abstract Title]. - Society for Neuroscience

Poster
252. Demyelinating Disorders: Mechanisms and Therapeutics II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 252.1/W25
Topic: C.08.a. Molecular and cellular mechanisms
Support: American Academy of Neurology Foundation
NIH IDDRC P30HD40677
Title: Alterations in Olig1 and MBP after ER stress in oligodendrocyte progenitor cells
Authors: *A. TAKANOHASHI, A. VANDERVER;
Ctr. for Genet. Med., Children's Natl. Med. Cntr, Washington, DC, DC
Abstract: Introduction: Recent studies have suggested that endoplasmic reticulum (ER) stress
may be involved in variety of disorders of the white matter of the brain. We hypothesize that an
altered stress response in oligodendrocytes leads to altered myelin related protein transcription
and expression. Clarification of the impact of ER stress on oligodendrocytes and myelin proteins
will lead to improved understanding of white matter disorders in which ER stress has been
implicated, such as multiple sclerosis, ischemia and leukodystrophies.
Methods: OliNeu, a mouse oligodendrocyte progenitor cell line, was cultured in basal medium
and differentiated to mature oligodendrocytes with 2mM dibutyryl cyclic adenosine 3‟, 5‟monophosphate
(dcAMP) or de-differentiated with 10ng/mL of PDGF and 10ng/mL of bFGF.
Cells were subjected to ER stress inducing compounds, such as thapsigargin (TG) and
tunicamycin (TUN), in dose and time series experiments. Cell activity/viability was assessed by
MTT assay, and the effects of stress on myelin related proteins were analyzed by
immunocytochemistry and western blot.
Results:
At early time points, 3 hr to 6 hr, TG (0.5 µM-2.5µM) stimulated MTT reduction in OliNeu
cells, while longer treatment, such as 15 hr and 24 hr, decreased MTT to 80% and 60%,
respectively. Various concentrations of TUN (0.1-5µg/mL) showed a 20% and 60% reduction of
MTT compared to controls in OliNeu at 6 hr and 24 hr, respectively. Neither differentiation
treatments dcAMP or PDGF/bFGF altered the expression of myelin basic protein (MBP) or
Olig1, but TG decreased both MBP and Olig1 protein expression in a dose dependent fashion
(p