Regional glutamine levels and cognition in patients with schizophrenia and healthy control subjects

Motivation: To better understand the neurochemical correlates of cognitive impairment in subjects with schizophrenia and healthy control subjects. Goal(s): Are regional brain metabolite levels and peripheral markers correlated with cognition in subjects with schizophrenia?Approach: Regional brain metabolism using 7T MRS, detailed neuropsychological testing, and peripheral markers from venipuncture were obtained in 12 subjects with schizophrenia and 9 healthy control subjects. Results: In all subjects, significant positive correlations were found between regional glutamine (Gln) levels and blood ammonia levels, and, in subjects with schizophrenia, regional brain Gln levels were negatively correlated with measures of cognition. Impact: These preliminary data support the hypothesized role of aberrant Gln metabolism as one of the factors associated with CI in schizophrenia, possibly by perturbation of the glutamate/GABA-glutamine neurotransmitter cycle.