Integrated metabolomic analysis for intervention effects of Gushudan on glucocorticoid-induced osteoporostic rat plasma based on RP/HILIC-UHPLC-Q-Orbitrap HRMS.

An integrated metabolomic strategy based on both RP-UHPLC-Q-Orbitrap HRMS and HILIC-UHPLC-Q-Orbitrap HRMS in rat plasma was developed and validated, to further understand the anti-osteoporosis effect of Gushudan (GSD) and its mechanism on glucocorticoid-induced osteoporosis (GIOP) rats in this study. The metabolites were separated and identified on C18 column (100 mm × 2.1 mm, 1.7 μm) and Amide column (100 mm × 2.1 mm, 1.7 μm) using the UHPLC-Q-Orbitrap system (Thermo Fisher Scientific, USA). As a result, a total of 40 differential metabolites were identified, which were mainly related to lipid metabolism, amino acid metabolism, energy metabolism and intestinal flora metabolism. It's worth mentioning that some new potential biomarkers associated with osteoporosis such as 3-hdroxybutyric acid and glycocholic acid were discovered in this study for the first time. With pattern recognition analysis of metabolite profile, a clear separation of the model group and the control group was acquired for plasma samples. The GSD group showed a predisposition towards recovery mimicking the control group, which was in agreement with the behavioral and biochemical results. The present study suggested that GSD had significant anti-osteoporotic effects on glucocorticoid-induced osteoporosis rat plasma, which might be attributed to regulating multiple metabolic pathways. Thus, metabolomics would be a useful tool in the evaluation of the efficacy and elucidation of the mechanism underlying the complex traditional Chinese medicine prescriptions.