An east meets west theory of depression : from Zang Fu to neuroscience

Abstract

Background: Depression has a high reported prevalence worldwide. The pathologies of depression in Western medicine may involve neurotransmitter, neuroendocrine, gene, and environmental factors. However, traditional Chinese medicine (TCM) has its own views to interpret the concept of depression. Therefore, this study aimed to explore the mechanisms of depression based on an integrated Eastern and Western approach. Methods: An extensive theoretical review was first performed, summarizing the existing literature to create plausible pathways linking TCM-based organ function and depression. In the second stage of the project, a total of 100 depressed adults were assessed on their clinical performance, neurophysiological biomarkers, and TCM- based organ function. The third stage was a pilot randomized controlled trial to investigate the safety and efficacy of Baduanjin exercise in patients with major depressive disorder (MDD). The Baduanjin group took part in a 10-week Baduanjin program, while the control group continued with their usual routine. Assessments were conducted at baseline and 5 and 10 weeks after the intervention. Results: The theoretical review found that TCM-based liver, spleen, and heart function might be interpreted by Western medicine as the neuroendocrine system, tryptophan and serotonin deficiencies, and hypoactivation of the frontal cortex. The path analysis targeting the TCM-based liver function of depression found a significant association between TCM-based liver function and cortisol, adrenocorticotrophic hormone (ACTH), and norepinephrine (NE). A marginally significant link was observed between NE and heart rate variability (HRV). Moreover, significant changes were found in the Hamilton Rating Scale for Depression-17 (HRSD17), cortisol, ACTH, and TCM-based liver function after the 10-week Baduanjin intervention compared with baseline scores. The improvement trends in HRSD17, TCM-based liver function, cortisol, and ACTH were only observed in the Baduanjin group. Discussion and implications: Although tremendous differences exist between Eastern and Western medicine theories, this study provides evidence to support the hypothetical model of the relationship between the hypothalamic-pituitary-adrenal (HPA) axis and TCM-based liver function in individuals with depression. This implies that TCM is not only based on clinical experience but also supported by scientific approaches. Additionally, a non-significant association was found between NE, HRV, and TCM-based liver function in depressed adults. This suggests that TCM- based liver function may not be explained by the locus coeruleus and norepinephrine system. Furthermore, significant improvements were found in HRSD17, TCM-based liver function, cortisol, and ACTH after a 10-week Baduanjin intervention in patients with MDD. This suggests that Baduanjin exercise had beneficial effects on MDD. Although no between-group difference was found after the Baduanjin intervention, the trends of improvement towards HRSD17, TCM-based liver function, cortisol, and ACTH were noticed in the Baduanjin group 5 and 10 weeks after the intervention.Baduanjin is a safe and effective therapy for MDD. These findings serve as a blueprint for further experimental studies, especially integrating Eastern and Western approaches to depression.