Acupuncture Can Play an Antidepressant Role by Regulating the Intestinal Microbes and Neurotransmitters in a Rat Model of Depression

BACKGROUND: Acupuncture, which has many good effects and few adverse effects, is widely recognized as an alternative therapy for depression in clinical practice. This study aimed to explore the mechanism of acupuncture in antidepressant treatment. MATERIAL/METHODS: In this experiment, Sprague-Dawley rats were randomly divided into 4 groups: control, chronic unpredictable mild stress (CUMS), acupuncture, and fluoxetine groups. The CUMS, acupuncture, and fluoxetine groups were orphaned and subjected to chronic unpredictable stress for 6 weeks, and the acupuncture and fluoxetine groups were treated with their respective intervention in weeks 4–6. The body weight of rats was monitored weekly. After behavioral tests were completed, serum, feces, and hippocampal tissue of rats were collected. RESULTS: The results showed that the acupuncture and fluoxetine treatments could alleviate the behavioral changes caused by CUMS. The treatments increased the total distance of rat crossing in the open-field test, prolonged the activity time of the open cross maze in the open arm, and improved the rate of sucrose consumption in the sucrose preference test. In addition, both the decreased level of dopamine (DA) and 5-hydroxytryptamine (5-HT) in serum and hippocampus caused by CUMS were improved after the treatments with acupuncture and fluoxetine, and the decreased expression of brain-derived neurotrophic factor signaling and the astrocytes in the hippocampus caused by CUMS were increased after the treatments with acupuncture and fluoxetine. Acupuncture and fluoxetine also decreased the β isoform of calmodulin-dependent protein kinase II in the hippocampus, which was increased by CUMS. Furthermore, acupuncture regulated intestinal microbial disorders caused by CUMS, which reduced the relative abundance ratio of Bacteroidetes/Firmicutes in rats. CONCLUSIONS: Our experimental results indicate that acupuncture can alleviate depression-like performance in CUMS rats by regulating intestinal microbes and neurotransmitters.