Brain chemical elevations identified in early stage of psychosis

According to a study, published in Biological Psychiatry, individuals experiencing their first episode of psychosis may show particular brain chemical abnormalities: glutamate (Glu) and glycine (Gly).

The study, led by Dr. Dost Öngür of Harvard Medical School and his team of researchers, aimed at measuring the levels of the neurotransmitters glutamate and glycine using a magnetic resonance spectroscopy (MRS) in patients with their first-episode of psychosis. There were 46 participants with first-episode psychosis (20 with schizophrenia and 26 with bipolar disorder), in addition to 50 age-matched healthy participants.

“Glu and Gly levels were measured in vivo in the anterior cingulate cortex and posterior cingulate cortex of the subjects by using the echo time–averaged proton MRS technique at 4T (i.e., modified point resolved spectroscopy sequence: 24 echo time steps with 20-ms increments). Metabolite levels were quantified using LCModel with simulated basis sets,” the study reads.

The findings, unexpectedly, led researchers to the conclusion that glycine levels were higher in the 46 participants with first-episode psychosis, compared to the 50 healthy participants.

“Our findings suggest that glycine abnormalities may play a role in the earliest phases of psychotic disorders,” said Dr. Öngür, one of the lead researchers.

Additionally, researchers found increased levels of glutamate, and suggest that the elevations from both brain chemicals prove NMDA receptors transmits abnormal simulation in psychotic disorders.

“In conclusion, we report abnormal brain Glu and Gly levels in patients with first-episode psychosis by means of TE-averaged 1H-MRS at 4T, and that the pattern of our findings was consistent with the involvement of NMDAR hypofunction in the pathophysiology of early-stage psychosis,” the study affirms.

“Future research coupling these observations with intervention studies to address these dysfunctions would be of great interest.”