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Prostaglandin D2-mediated microglia/astrocyte interaction enhances astrogliosis and demyelination in twitcher.

ABSTRACT: Prostaglandin (PG) D2 is well known as a mediator of inflammation. Hematopoietic PGD synthase (HPGDS) is responsible for the production of PGD2 involved in inflammatory responses. Microglial activation and astrogliosis are commonly observed during neuroinflammation, including that which occurs during demyelination. Using the genetic demyelination mouse twitcher, a model of human Krabbe's disease, we discovered that activated microglia expressed HPGDS and activated astrocytes expressed the DP1 receptor for PGD2 in the brain of these mice. Cultured microglia actively produced PGD2 by the action of HPGDS. Cultured astrocytes expressed two types of PGD2 receptor, DP1 and DP2, and showed enhanced GFAP production after stimulation of either receptor with its respective agonist. These results suggest that PGD2 plays an important role in microglia/astrocyte interaction. We demonstrated that the blockade of the HPGDS/PGD2/DP signaling pathway using HPGDS- or DP1-null twitcher mice, and twitcher mice treated with an HPGDS inhibitor, HQL-79 (4-benzhydryloxy-1-[3-(1H-tetrazol-5-yl)-propyl]piperidine), resulted in remarkable suppression of astrogliosis and demyelination, as well as a reduction in twitching and spasticity. Furthermore, we found that the degree of oligodendroglial apoptosis was also reduced in HPGDS-null and HQL-79-treated twitcher mice. These results suggest that PGD2 is the key neuroinflammatory molecule that heightens the pathological response to demyelination in twitcher mice.

SUBMITTER: Mohri I

PROVIDER: S-EPMC6673986 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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Prostaglandin D2-mediated microglia/astrocyte interaction enhances astrogliosis and demyelination in twitcher.

Mohri Ikuko I Taniike Masako M Taniguchi Hidetoshi H Kanekiyo Takahisa T Aritake Kosuke K Inui Takashi T Fukumoto Noriko N Eguchi Naomi N Kushi Atsuko A Sasai Hitoshi H Kanaoka Yoshihide Y Ozono Keiichi K Narumiya Shuh S Suzuki Kinuko K Urade Yoshihiro Y

The Journal of neuroscience : the official journal of the Society for Neuroscience 20060401 16

Prostaglandin (PG) D2 is well known as a mediator of inflammation. Hematopoietic PGD synthase (HPGDS) is responsible for the production of PGD2 involved in inflammatory responses. Microglial activation and astrogliosis are commonly observed during neuroinflammation, including that which occurs during demyelination. Using the genetic demyelination mouse twitcher, a model of human Krabbe's disease, we discovered that activated microglia expressed HPGDS and activated astrocytes expressed the DP1 re ...[more]

PMID: 16624958

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Dataset Information

Prostaglandin D2-mediated microglia/astrocyte interaction enhances astrogliosis and demyelination in twitcher.

Publications

Prostaglandin D2-mediated microglia/astrocyte interaction enhances astrogliosis and demyelination in twitcher.

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