TY - JOUR
T1 - Enhanced integrated stress response promotes myelinating oligodendrocyte survival in response to interferon-γ
AU - Lin, Wensheng
AU - Kunkler, Phillip E.
AU - Harding, Heather P.
AU - Ron, David
AU - Kraig, Richard P.
AU - Popko, Brian
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2008/11
Y1 - 2008/11
N2 - The T-cell-derived, pleiotropic cytokine interferon (IFN)-γ is believed to play a key regulatory role in immune-mediated demyelinating disorders of the central nervous system, including multiple sclerosis and experimental autoimmune encephalomyelitis. Our previous work has demonstrated that the endoplasmic reticulum (ER) stress response modulates the response of oligodendrocytes to this cytokine. The ER stress response activates the pancreatic ER kinase, which coordinates an adaptive program known as the integrated stress response by phosphorylating translation initiation factor 2α (eIF2α). In this study, we found that growth arrest and DNA damage 34 (GADD34), a stress-inducible regulatory subunit of a phosphatase complex that dephosphorylates eIF2α, was selectively up-regulated in myelinating oligodendrocytes in mice that ectopically expressed IFN-γ in the central nervous system. We also found that a GADD34 mutant strain of mice displayed increased levels of phosphorylated eIF2α (p-eIF2α) in myelinating oligodendrocytes when exposure to IFN-γ, as well as diminished oligodendrocyte loss and hypomyelination. Furthermore, treatment with salubrinal, a small chemical compound that specifically inhibits protein phosphatase 1(PP1)-GADD34 phosphatase activity, increased the levels of p-eIF2α and ameliorated hypomyelination and oligodendrocyte loss in cultured hippocampal slices exposed to IFN-γ. Thus, our data provide evidence that an enhanced integrated stress response could promote oligodendrocyte survival in immune-mediated demyelination diseases.
AB - The T-cell-derived, pleiotropic cytokine interferon (IFN)-γ is believed to play a key regulatory role in immune-mediated demyelinating disorders of the central nervous system, including multiple sclerosis and experimental autoimmune encephalomyelitis. Our previous work has demonstrated that the endoplasmic reticulum (ER) stress response modulates the response of oligodendrocytes to this cytokine. The ER stress response activates the pancreatic ER kinase, which coordinates an adaptive program known as the integrated stress response by phosphorylating translation initiation factor 2α (eIF2α). In this study, we found that growth arrest and DNA damage 34 (GADD34), a stress-inducible regulatory subunit of a phosphatase complex that dephosphorylates eIF2α, was selectively up-regulated in myelinating oligodendrocytes in mice that ectopically expressed IFN-γ in the central nervous system. We also found that a GADD34 mutant strain of mice displayed increased levels of phosphorylated eIF2α (p-eIF2α) in myelinating oligodendrocytes when exposure to IFN-γ, as well as diminished oligodendrocyte loss and hypomyelination. Furthermore, treatment with salubrinal, a small chemical compound that specifically inhibits protein phosphatase 1(PP1)-GADD34 phosphatase activity, increased the levels of p-eIF2α and ameliorated hypomyelination and oligodendrocyte loss in cultured hippocampal slices exposed to IFN-γ. Thus, our data provide evidence that an enhanced integrated stress response could promote oligodendrocyte survival in immune-mediated demyelination diseases.
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U2 - 10.2353/ajpath.2008.080449
DO - 10.2353/ajpath.2008.080449
M3 - Article
C2 - 18818381
AN - SCOPUS:55349142516
VL - 173
SP - 1508
EP - 1517
JO - American Journal of Pathology
JF - American Journal of Pathology
SN - 0002-9440
IS - 5
ER -