Journal
BIOLOGICAL PSYCHIATRY
Volume 78, Issue 11, Pages 763-774Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.biopsych.2015.02.026
Keywords
Adenosine; Astrocytes; A(2A)R; GLT-I; NMDA-R; Schizophrenia
Categories
Funding
- National Institutes of Health/National Institute of Neurological Disorders and Stroke
- National Institute of Mental Health [NS041083-11, NS073947, MH083973]
- National Alliance for Research on Schizophrenia and Depression, Defense Advanced Research Projects Agency grants [09-68-ESR-FP-010, W911NF-10-1-0059]
- Portuguese Foundation for Science and Technology (FCT) [PTDC/SAU-NSC/122254/2010]
- Quadro de Referencia Estrategico Nacional [CENTRO-07-ST24-FEDER-002006]
- FCT/Fundo Social Europeu fellowship [SFRH/BD/36289/2007, SFRH/BD/47824/2008]
- Boston University Clinical and Translational Science Institute
Ask authors/readers for more resources
BACKGROUND: Adenosine A(2A) receptors (A(2A)R) modulate dopamine and glutamate signaling and thereby may influence some of the psychomotor and cognitive processes associated with schizophrenia. Because astroglial A(2A)R regulate the availability of glutamate, we hypothesized that they might play an unprecedented role in some of the processes leading to the development of schizophrenia, which we investigated using a mouse line with a selective deletion of A(2A)R in astrocytes (Gfa2-A(2A)R knockout [KO] mice]. METHODS: We examined Gfa2-A(2A)R KO mice for behaviors thought to recapitulate some features of schizophrenia, namely enhanced MK-801 psychomotor response (positive symptoms) and decreased working memory (cognitive symptoms). In addition, we probed for neurochemical alterations in the glutamatergic circuitry, evaluating glutamate uptake and release and the levels of key proteins defining glutamatergic signaling (glutamate transporter-I [GLT-I], N-methyl-D-aspartate receptors [NMDA-R] and alpha-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors [AMPA-R]) to provide a mechanistic understanding of the phenotype encountered. RESULTS: We show that Gfa2-A(2A)R KO mice exhibited enhanced MK-801 psychomotor response and decreased working memory; this was accompanied by a disruption of glutamate homeostasis characterized by aberrant GLT-I activity, increased presynaptic glutamate release, NMDA-R 2B subunit upregulation, and increased internalization of AMPA-R. Accordingly, selective GLT-I inhibition or blockade of GluR1/2 endocytosis prevented the psychomotor and cognitive phenotypes in Gfa2-A(2A)R KO mice, namely in the nucleus accumbens. CONCLUSIONS: These results show that the dysfunction of astrocytic A(2A)R, by controlling GLT-I activity, triggers an astrocyte-to-neuron wave of communication resulting in disrupted glutamate homeostasis, thought to underlie several endophenotypes relevant to schizophrenia.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available