Abstract |
D-Amino acid oxidase (DAO) is a peroxisomal flavoenzyme that catalyzes oxidative deamination of a wide range of D- amino acids. Among the possible substrates of DAO in vivo, D- serine is proposed to be a neuromodulator of the N-methyl-D-aspartate ( NMDA) type glutamate receptor. The gene for DAO was reported to be associated with schizophrenia. Since DAO is expected to be one of the key enzymes in the regulation of NMDA neurotransmission, the modulation of the enzyme activity is expected to be therapeutical for neuronal disorders. In search of the pathophysiological role of DAO, we analyzed the distribution of DAO mRNA and protein in the rat and human brain. In rat, the distribution of DAO mRNA was newly detected in choroid plexus (CP) epithelial cells in addition to glial cells of pons, medulla oblongata, and especially Bergmann glia of cerebellum. Moreover, to investigate how DAO expression level is altered in schizophrenia, we performed immunohistochemistry in the human brain. In agreement with the results in the rat brain, the immunoreactivity for DAO was detected in glial cells of rhombencephalon and in CP. Furthermore, higher level of DAO expression was observed in schizophrenic CP epithelial cells than that in non-schizophrenic cases. These results suggest that an increase in DAO expression in parts of the brain is involved in aberrant D- amino acid metabolism. In particular, gene expression of DAO in CP suggests that DAO may regulate D- amino acid concentration by modulating the cerebrospinal fluid and may be regarded as a potential therapeutic target for schizophrenia.
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Authors | Koji Ono, Yuji Shishido, Hwan Ki Park, Tomoya Kawazoe, Sanae Iwana, Seong Pil Chung, Rabab M Abou El-Magd, Kazuko Yorita, Mai Okano, Takeshi Watanabe, Nobuya Sano, Yoshimi Bando, Kunimasa Arima, Takashi Sakai, Kiyoshi Fukui |
Journal | Journal of neural transmission (Vienna, Austria : 1996)
(J Neural Transm (Vienna))
Vol. 116
Issue 10
Pg. 1335-47
(Oct 2009)
ISSN: 1435-1463 [Electronic] Austria |
PMID | 19685198
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- RNA, Messenger
- D-Amino-Acid Oxidase
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Topics |
- Aged
- Animals
- Brain
(enzymology, metabolism)
- Choroid Plexus
(enzymology, metabolism)
- D-Amino-Acid Oxidase
(metabolism)
- Epithelial Cells
(enzymology, metabolism)
- Humans
- Immunohistochemistry
- In Situ Hybridization
- Male
- Middle Aged
- Neuroglia
(enzymology, metabolism)
- RNA, Messenger
(metabolism)
- Rats
- Rats, Sprague-Dawley
- Schizophrenia
(enzymology, metabolism)
- Species Specificity
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