Optogenetic Dissection of Neural Circuits Underlying Stress-Induced Mood Disorders

Abstract

Objectives: This review aims to (i) summarize the literature on optogenetic applications of different stress-induced mood disorder models of the medial prefrontal cortex (mPFC) and its projection circuits, and (ii) examine methodological variability across the literature and how such variations may influence the underlying circuits of stress-induced mood disorders.Methods: A variety of databases (PubMed, Web of Science, Elsevier, Springer, and Wiley) were systematically searched to identify optogenetic studies that applied to mood disorders in the context of stress.Results: Eleven studies on optogenetic stimulation of the mPFC and the effect of its efferent circuitry on anxiety- and depression-like behaviors in different rodent models were selected. The results showed that the optogenetics (i) can provide insights into the underlying circuits of mood disorders in the context of stress (ii) and also points out new therapeutic strategies for treating mood disorders.Conclusions: These findings indicate a clear role for the mPFC in social avoidance, and highlight the central role of stress reactivity circuitry that may be targeted for the treatment of stress-induced mood disorders.

Measuring Anxiety-Like Behaviors in Rodent Models of Traumatic Brain Injury

“…The authors reported that only about 13% of the injured animals were found to be "vulnerable, " showing increased exploration of anxiogenic regions during testing compared to baseline behavior and to sham-treated animals (Popovitz et al, 2021). The behavior of the vulnerable mice had neurobiological correlates in the medial prefrontal cortex, basolateral amygdala, and ventral hippocampus; all areas that are associated with stress and anxiety (Almeida-Suhett et al, 2014;Bryant and Barker, 2020;Kenwood et al, 2021;Liu et al, 2021;McCorkle et al, 2021;Pentkowski et al, 2021). Statz et al employed a different "affective profiling" technique to identify "affected" and "unaffected" rats 3 weeks or 6 months following exposure to repeated blast overpressure (Statz et al, 2019).…”

Optogenetic behavioral studies in depression research: A systematic review

“…Previous reviews have drawn conclusions that connect optogenetic interventions to the disease mechanisms of depression. 27 , 28 , 30 , 82 , 83 , 84 Most of these reviews provide qualitative analyses of a wide range of research results and discuss relevant brain targets involved in the mechanistic picture of depression. In addition, some articles discussed the accessibility of specific neuronal circuits for DBS.…”