Integrated dose-response metabolomics with therapeutic effects and adverse reactions may demystify the dosage of traditional Chinese medicine.

Background: Traditional Chinese medicine (TCM) has been used to treat various diseases for thousands of years. However, the uncertainty of dosage as well as the lack of systemic evaluation of pharmacology and toxicology is one major reason why TCM remains mysterious and is not accepted worldwide. Hence, we aimed to propose an integrated dose-response metabolomics strategy based on both therapeutic effects and adverse reactions to guide the TCM dosage in treatment.

Methods: The proposed methodology of integrated dose-response metabolomics includes four steps: dose design, multiple comparison of metabolic features, response calculation and dose-response curve fitting. By comparing the changes of all metabolites under different doses and calculating these changes through superposition, it is possible to characterize the global disturbance and thus describe the overall effect and toxicity of TCM induced by different doses. Rhubarb, commonly used for constipation treatment, was selected as a representative TCM.

Results: This developed strategy was successfully applied to rhubarb. The dose-response curves clearly showed the efficacy and adverse reactions of rhubarb at different doses. The rhubarb dose of 0.69 g/kg (corresponding to 7.66 g in clinic) was selected as the optimal dose because it was 90% of the effective dose and three adverse reactions were acceptable in this case.

Conclusion: An integrated dose-response metabolomics strategy reflecting both therapeutic effects and adverse reactions was established for the first time, which we believe is helpful to uncover the mysterious veil of TCM dosage. In addition, this strategy benefits the modernization and internationalization of TCM, and broadens the application of metabolomics.