Study on the Antidepressant Effect of Zhizichi Decoction by Regulating Metabolism and Intestinal Flora

Background: The incidence of depression is increasing year by year, and Zhizichi Decoction（ZZCD）has shown significant efficiency in the clinical treatment of mild depression, but its mechanism of action is still unclear. In this research, network pharmacology and metagenomics combined and metabolomics were used as research methods to explain the scientific connotation of the antidepressant effect of ZZCD from the aspects of the overall effect of organisms and microbial structure and function. Methods: The rat model of depression was established by chronic unpredictable mild stress (CUMS), and the improvement of depressive symptoms was evaluated by behavioral and histopathological methods. Network pharmacology predicted possible targets and important pathways of ZZCD. Metabolomics revealed its possible related biological pathways. Metagenomics showed the disturbance of ZZCD on intestinal microbial diversity structure and associated biological functions in depressed rats. Results: ZZCD can improve the behavioral performance of CUMS rats, and can significantly regulate the content of 5-HT, NE and other neurotransmitters in serum and brain tissue, and improve the damaged state of neurons in the hippocampus. Network pharmacology predicts that it mainly acts on biological processes such as inflammatory response and oxidative stress response. Metabolomics found that it affected metabolic pathways such as amino acid metabolism and lipid metabolism. The results of metagenomics showed that it significantly regulated the abundance of Firmicutes and Bacteroidetes. The above results predicted that it may affect signaling pathways such as the nervous system, inflammatory diseases and cell processing. Conclusion: ZZCD may play an antidepressant role by regulating intestinal probiotics, energy metabolism, and inflammation reduction. This provides a scientific basis for the clinical application of ZZCD in traditional Chinese medicine and also makes it an optional alternative for the treatment of depression.