A Traditional Chinese Medicine Approach in Treating Depression by Promoting Liver Qi Circulation: A Western Medicine Perspective

Depression is a prevalent mental illness in developed countries. In Western medicine, experimental and clinical investigations have demonstrated that depression is associated with the dysregulation of neurotransmitter signaling, and symptoms of depression can be alleviated by therapeutic intervention. However, patients taking antidepressant drugs often experience serious side effects and high relapse rates. On the other hand, traditional Chinese medicine (TCM) views depression as a manifestation of liver qi stagnation. Practitioners of TCM have long been treating depression with herbs that promote qi circulation in the liver. In this article, we offer a hypothesis stating the biochemical basis of the linkage between liver qi stagnation and depression. Liver qi is involved in the processing of macronutrients into molecules to fuel energy metabolism in brain neurons, as well as the synthesis of plasma proteins that maintain blood circulation to the brain, thereby enabling these fuel molecules to be delivered to the brain. In cases of liver qi stagnation, the failure in delivering sufficient fuel molecules to the brain disrupts mitochondrial ATP production in neurons. Because neurotransmitter release and neurotropin transport are driven by ATP, the deficiency in release and transport processes resulting from insufficient ATP production could lead to depression. Therefore, if liver qi stagnation is causally related to the pathogenesis of depression, the promotion of liver qi circulation by Chinese herbs might offer a promising prospect for the effective treatment of depression.