Brain volumetric and metabolic correlates of electroconvulsive therapy for treatment-resistant depression: a longitudinal neuroimaging study

The authors conducted a systematic review and meta-analysis of ketamine and other N-methyl-d-aspartate (NMDA) receptor antagonists in the treatment of major depression.

Although endogenous recruitment of adult neural stem cells has been proposed as a therapeutic strategy, clinical approaches for achieving this are lacking. Here, we show that metformin, a widely used drug, promotes neurogenesis and enhances spatial memory formation. Specifically, we show that an atypical PKC-CBP pathway is essential for the normal genesis of neurons from neural precursors and that metformin activates this pathway to promote rodent and human neurogenesis in culture. Metformin also enhances neurogenesis in the adult mouse brain in a CBP-dependent fashion, and in so doing enhances spatial reversal learning in the water maze. Thus, metformin, by activating an aPKC-CBP pathway, recruits neural stem cells and enhances neural function, thereby providing a candidate pharmacological approach for nervous system therapy. Copyright © 2012 Elsevier Inc. All rights reserved.

Adult-generated hippocampal neurons are required for mood control and antidepressant efficacy, raising hopes that someday we can harness the power of new neurons to treat mood disorders such as depression. However, conflicting findings from preclinical research--involving stress, depression, and neurogenesis--highlight the complexity of considering neurogenesis as a road to remission from depression. To reconcile differences in the literature, we introduce the "neurogenic interactome," a platform from which to consider the diverse and dynamic factors regulating neurogenesis. We propose consideration of the varying perspectives--system, region, and local regulation of neurogenesis--offered by the interactome and exchange of ideas between the fields of learning and memory and mood disorder research to clarify the role of neurogenesis in the etiology and treatment of depression.