title: Prefrontal NAA and Glx Levels in Different Stages of Psychotic Disorders: a 3T 1H-MRS Study.
abstract: H-Magnetic Resonance Spectroscopy ((1)H-MRS) can offer insights in various neuropathologies by measuring metabolite levels in the brain. In the current study we investigated the levels of glutamate + glutamine (Glx, neurotransmitter and precursor) and N-Acetyl Aspartate + glutamic acid (NAA + NAAG; neuronal viability) in the prefrontal cortex of patients with a psychotic disorder and people at Ultra High Risk (UHR) for psychosis. A (1)H-MRS spectrum was acquired in 31 patients with a recent onset psychotic disorder and 60 with a chronic state, 16 UHR patients and 36 healthy controls. Absolute metabolite levels were calculated using LCModel with a reference water peak. Groups were compared while taking into account age and partial volume effects. Moreover, we investigated associations with positive and negative symptoms, duration of illness, and antipsychotic treatment in patients. The most notable finding is that chronicity of schizophrenia was related to decreased levels of Glx and NAA. On the other hand, although on an exploratory note, UHR showed increased levels of prefrontal Glx and NAA levels with increasing age. Our results may indicate an initial Glx and NAA increase and subsequent decrease during illness progression that may be related to the neurotoxic effects of glutamate.
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Rob Giel Research Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Lentis Research, Center for Mental Health, Groningen, the Netherlands.
authors.forename: Edith
authors.initials: E
authors.lastname: Liemburg
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Anita
authors.initials: A
authors.lastname: Sibeijn-Kuiper
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Lentis Research, Center for Mental Health, Groningen, the Netherlands.
authors.forename: Leonie
authors.initials: L
authors.lastname: Bais
authors.affiliation: Department of Psychology, University of Groningen, Groningen, the Netherlands.|Department of Clinical Psychology and Experimental Psychopathology, Faculty of Behavioral and Social Sciences, University of Groningen, Groningen, the Netherlands.
authors.forename: Gerdina
authors.initials: G
authors.lastname: Pijnenborg
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Rob Giel Research Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Lentis Research, Center for Mental Health, Groningen, the Netherlands.
authors.forename: Henderikus
authors.initials: H
authors.lastname: Knegtering
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Jorien
authors.initials: J
authors.lastname: van der Velde
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Esther
authors.initials: E
authors.lastname: Opmeer
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Department of Clinical Psychology and Experimental Psychopathology, Faculty of Behavioral and Social Sciences, University of Groningen, Groningen, the Netherlands.
authors.forename: Annerieke
authors.initials: A
authors.lastname: de Vos
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
authors.forename: Jozarni
authors.initials: J
authors.lastname: Dlabac-De Lange
authors.affiliation: Rob Giel Research Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Department of Education and Research, Friesland Mental Health Care Services, Leeuwarden, the Netherlands.
authors.forename: Lex
authors.initials: L
authors.lastname: Wunderink
authors.affiliation: Department of Neuroscience, and BCN Neuroimaging Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.|Department of Psychology, University of Groningen, Groningen, the Netherlands.
authors.forename: André
authors.initials: A
authors.lastname: Aleman
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018377:Neurotransmitter Agents / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology; D066244:Proton Magnetic Resonance Spectroscopy; D011618:Psychotic Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D012044:Regression Analysis; D012306:Risk; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D014150:Antipsychotic Agents; D018377:Neurotransmitter Agents; D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate