TY - JOUR
T1 - Glutamate in schizophrenia
T2 - A focused review and meta-analysis of 1H-MRS studies
AU - Marsman, Anouk
AU - Van Den Heuvel, Martijn P.
AU - Klomp, Dennis W.J.
AU - Kahn, René S.
AU - Luijten, Peter R.
AU - Hulshoff Pol, Hilleke E.
PY - 2013/1
Y1 - 2013/1
N2 - Schizophrenia is a severe chronic psychiatric illness, characterized by hallucinations and delusions. Decreased brain volumes have been observed in the disease, although the origin of these changes is unknown. Changes in the n-methyl-d-aspartate (NMDA)-receptor mediated glutamatergic neurotransmission are implicated, since it is hypothesized that NMDA-receptor dysfunction in schizophrenia leads to increased glutamate release, which can have excitotoxic effects. However, the magnitude and extent of changes in glutamatergic metabolites in schizophrenia are not clear. With 1H magnetic resonance spectroscopy (1H-MRS), in vivo information about glutamate and glutamine concentrations can be obtained in the brain. A systematic search through the MEDLINE database was conducted to identify relevant 1H-MRS studies that examined differences in glutamate and glutamine concentrations between patients with schizophrenia and healthy control subjects. Twenty-eight studies were identified and included a total of 647 patients with schizophrenia and 608 healthy-control subjects. For each study, Cohen's d was calculated and main effects for group analyses were performed using the random-effects model. Medial frontal region glutamate was decreased and glutamine was increased in patients with schizophrenia as compared with healthy individuals. Group-by-age associations revealed that in patients with schizophrenia, glutamate and glutamine concentrations decreased at a faster rate with age as compared with healthy controls. This could reflect aberrant processes in schizophrenia, such as altered synaptic activity, changed glutamate receptor functioning, abnormal glutamine-glutamate cycling, or dysfunctional glutamate transport.
AB - Schizophrenia is a severe chronic psychiatric illness, characterized by hallucinations and delusions. Decreased brain volumes have been observed in the disease, although the origin of these changes is unknown. Changes in the n-methyl-d-aspartate (NMDA)-receptor mediated glutamatergic neurotransmission are implicated, since it is hypothesized that NMDA-receptor dysfunction in schizophrenia leads to increased glutamate release, which can have excitotoxic effects. However, the magnitude and extent of changes in glutamatergic metabolites in schizophrenia are not clear. With 1H magnetic resonance spectroscopy (1H-MRS), in vivo information about glutamate and glutamine concentrations can be obtained in the brain. A systematic search through the MEDLINE database was conducted to identify relevant 1H-MRS studies that examined differences in glutamate and glutamine concentrations between patients with schizophrenia and healthy control subjects. Twenty-eight studies were identified and included a total of 647 patients with schizophrenia and 608 healthy-control subjects. For each study, Cohen's d was calculated and main effects for group analyses were performed using the random-effects model. Medial frontal region glutamate was decreased and glutamine was increased in patients with schizophrenia as compared with healthy individuals. Group-by-age associations revealed that in patients with schizophrenia, glutamate and glutamine concentrations decreased at a faster rate with age as compared with healthy controls. This could reflect aberrant processes in schizophrenia, such as altered synaptic activity, changed glutamate receptor functioning, abnormal glutamine-glutamate cycling, or dysfunctional glutamate transport.
KW - aging
KW - glutamatergic system
KW - magnetic resonance spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=84871840525&partnerID=8YFLogxK
U2 - 10.1093/schbul/sbr069
DO - 10.1093/schbul/sbr069
M3 - Review article
C2 - 21746807
AN - SCOPUS:84871840525
SN - 0586-7614
VL - 39
SP - 120
EP - 129
JO - Schizophrenia Bulletin
JF - Schizophrenia Bulletin
IS - 1
ER -