Identification of differentially expressed genes in the medial prefrontal cortex of rats subjected to chronic unpredictable mild stress and treated with electroacupuncture

Abstract

Major depressive disorder is a chronic mental health condition that seriously impacts afflicted individuals. Although electroacupuncture has proven to be an effective therapy for depression, its underlying biological mechanism remains largely unknown. In this study, we aimed to investigate the effects of electroacupuncture on depression-like behavior and to identify potential target genes related to those effects. To achieve this, we subjected rats to chronic unpredictable mild stress (CUMS) and used sucrose preference, forced swimming, and open-field tests to determine their depression-like behavior in the absence or after receipt of electroacupuncture treatment. RNA sequencing technology was then used to reveal the differentially expressed genes associated with depression and electroacupuncture treatment effects in the medial prefrontal cortex (mPFC). Repeated electroacupuncture treatments at the Baihui (GV20) and Taichong (LR3) acupoints significantly alleviated depression-like behavioral defects in the animals. Genomic RNA sequencing revealed several significant changes in the mPFC transcriptome of rats that received treatment. Through differential gene expression analysis, we found that electroacupuncture reversed the CUMS-induced downregulation of 46 genes and upregulation of 13 genes. Among the differentially expressed genes, Casr, Bdkrb2, Gnb3, and Ccl1 were found to be associated with depression and electroacupuncture treatment effects. In conclusion, we verified that electroacupuncture treatment has an effective antidepressant effect, and the underlying mechanism involves multiple systems and targets.