Strategy of systems biology for visualizing the “Black box” of traditional Chinese medicine

Traditional Chinese medicine (TCM) has been practiced for thousands of years in China. TCM formula, usually composed of several or even dozens of herbal medicines, is the main form of TCM practicing, which is extremely complex due to multiple components and therapeutic targets, especially the characteristics of formula compatibility. Thus, it is an enormous challenge for the modernization of TCM. Systems biology is a strategy for investigating the complex interactions between genes, mRNA, proteins, and metabolites by using integrated omics approaches. In recent years, systems biology has been increasingly adopted in TCM study. This review comprehensively summarized status of syndrome and application of TCM formulae in clinical and preclinical studies and discussed the advances of systems biology in TCM research. Then, a "Disease-Syndrome-Formulae-Effect" strategy was proposed for TCM research. Combination of systems biology and "Disease-Syndrome-Formulae-Effect" strategy provided a novel approach to understand the complex interactions among biological systems, drugs, and complex diseases from a network perspective, thus facilitating the modernization of TCM. The objective of this manuscript is to provide comprehensive and up-to-date review on the application of systems biology in TCM research, as well as the perspective of TCM modernization with systems biology.