Molecular mechanism of reward treatment ameliorating chronic stress-induced depressive-like behavior assessed by sequencing miRNA and mRNA in medial prefrontal cortex

Abstract

Background Major depressive disorder (MDD) is a disease that seriously endangers human health and mental state. Chronic stress and lack of reward may reduce the function of the brain's reward circuits, leading to major depressive disorder. The effect of reward treatment on chronic stress-induced depression-like behaviors and its molecular mechanism in the brain remain unclear.Methods Mice were divided into the groups of control, chronic unpredictable mild stress (CUMS), and CUMS-companion. Mice of CUMS group was performed by CUMS for 4 weeks, and CUMS-companion group was treated by CUMS accompanied with companion. The tests of sucrose preference, Y-maze, and forced swimming were conducted to assess depression-like behaviors or resilience. High-throughput sequencing was used to analyze mRNA and miRNA profiles in the medial prefrontal cortex harvested from control, CUMS-MDD (mice with depression-like behaviors in CUMS group), Reward-MDD (mice with depression-like behaviors in CUMS-companion group), CUMS-resilience (resilient mice in CUMS group), Reward-resilience (resilient mice in CUMS-companion group) mice.Results The results provided evidence that accompanying with companion ameliorated CUMS-induced depression-like behaviors in mice. 45 differentially expressed genes (DEGs) are associated with depression-like behaviors, 8 DEGs are associated with resilience and 59 DEGs are associated with nature reward (companion) were identified. Furthermore, 196 differentially expressed miRNAs were found to be associated with companion. Based on the differentially expressed miRNAs and DEGs data, miRNA-mRNA network was established to be associated with companion.Conclusion Taken together, our data here provided a method to ameliorate depression-like behaviors, and numerous potential drug targets for the prevention or treatment of depression.