Background: Major depressive disorder is a leading cause of disability worldwide, affecting up to 17 % of the general population. The neural mechanisms of depression, however, are yet to be uncovered. Recently, attention has been drawn to the effects of dysfunctional brain-gut axis on depression, and many substances have been suggested to be involved in the communication between the gut and brain, such as ghrelin.
Methods: We herein systematically examined the changes of metabolomics after unpredictable chronic mild stress (UCMS)-induced depression-like behaviors in rats and compared the altered metabolites in the hippocampus and jejunum samples.
Results: Our results show that many metabolites significantly changed with UCMS both in the hippocampus and jejunum, such as L-glutamine, L-tyrosine, hydroxylamine, and 3-phosphoglyceric acid. Further studies suggested that these changes are the reasons for anxiety-like behaviors and depression-like behaviors in UCMS rats and also are the reasons for hippocampal neural plasticity.
Conclusions: Coexistence of brain and gut metabolic changes in UCMS-induced depressive behavior in rats suggests a possible role of brain-gut axis in depression. This study provides insights into the neurobiology of depression.
Keywords: Brain-gut axis; MDD; Major depressive disorders; Metabolomics; UCMS.
© 2021. The Author(s).