Exploring the Mechanism of the Action of Acupuncture in the Treatment of Depression Based on the Brain-Gut Axis Theory

Depression is a common clinical affective disorder, characterized by low affect, apathy, and delayed speech and movement as typical symptoms. It is often accompanied by gastrointestinal symptoms, such as constipation and eructation. At present, conventional antidepressants are associated with significant adverse effects, and they aggravate gastrointestinal symptoms. Acupuncture is effective in treating depression, but its mechanism of action is not clear; research has shown that acupuncture can treat depression through the brain-gut axis. For example, a randomized controlled trial by Sun Y showed that abdominal acupuncture targeting brain-gut related acupoints could improve depressive symptoms in methamphetamine withdrawal patients and regulate brain-gut peptides at the same time. This article has introduced the doctrine of the brain-gut axis and the influence of the brain-gut axis on depression, and discussed the mechanism of action of acupuncture in treating depression through the brain-gut axis; it has also highlighted acupoint selection strategies for acupuncture in treating depression via the brain-gut axis. By integrating modern neurobiological insights with traditional Chinese medicine (TCM) theory, this review aimed to provide novel perspectives and evidence-based references for clinical practice.