A metabolomics study on the immunosuppressive effect of Tripterygium hypoglaucum (Levl.) Hutch in mice: The discovery of pathway differences in serum metabolites.

Tripterygium hypoglaucum (Levl.) Hutch (THH), a typical traditional Chinese medicine, is widely used in clinical practice for the treatment of rheumatoid arthritis, systemic lupus erythematous, and other connective tissue and autoimmune diseases. However, most related researches focused on the pharmacological effects of THH, while less attention has been paid to the immunosuppressive mechanism. The present study aims to determine the metabolic profiles, based on UPLC-Q-TOF-MS, identify differential metabolites, and find related metabolic pathways among the sensitization red blood cell (SRBC) model mice, THH treated mice, and cyclophosphamide treated group. Totally, 24 and 19 changed metabolites were found in the THH and cyclophosphamide treated groups respectively. Among them, we found that urocanate metabolic pathway change could be considered as the most relevant pathway associated with immunosuppression. This is the first study that comprehensively assessed the differences in metabolome between the model and THH treated groups. The results provide insights into the difference between the immunosuppressive mechanisms of THH and cyclophosphamide and also demonstrated that metabolomics is a valuable tool for investigating the efficacy of drugs in the treatment of diseases and the associated mechanism involved.