Symposium Abstract: ANCIPS 2022: Metabolic abnormalities in Depression

Major depression and bipolar disorder are common conditions with substantial negative consequences for sufferers. Understanding the biological changes associated with these conditions is a major research priority, and a better understanding of their biological basis could lead to improved diagnosis and treatment. There is growing interest in the development of precision medicine algorithms with the aim of tailoring treatment strategies to individual patients according to unique biological signatures. This biomarker-based approach to precision prescribing has the potential to improve therapeutic response, minimize adverse reactions, and reduce time to symptomatic relief. However, few validated biological targets for treatment response prediction in depression have been identified to date. Biomarkers derived from neuroimaging data are potentially important contributors to the goal of guiding treatment selection using clinical and bio-typing data. Information on brain structure and function may be used to predict response versus non-response to various treatments. Ignited by the observation of a rapid antidepressant effect of the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine, the glutamate system has emerged as a leading focus for novel drug discovery for depression and other mood disorders. Over the last two decades, neuroimaging has brought a deeper understanding of neurobiological alterations associated with these conditions, and researchers are moving towards developing these methods to diagnose and treat affective disorders. This research has been aided by developments in magnetic resonance spectroscopy (MRS), a method that allows non-invasive measurement of glutamate and glutamine levels in vivo. Glutamate and glutamine levels are typically found to be reduced in unipolar depression, most notably in prefrontal regions such as the anterior cingulate cortex, while studies in bipolar disorder suggests an increase in glutamate in this region.