A Comprehensive Study on the Chemical Constituents and Pharmacokinetics ofErzhi Formula and Jiawei Erzhi Formula Based on Targeted and Untargeted LC-MSAnalysis

Background: Erzhi formula (EZF) is a traditional Chinese medicine prescription, which has been widely used in the treatment of osteoporosis and premature ovarian failure. Objective: To enhance curative effects, the other two herbal medicines, including Spatholobi Caulis (SC) and Achyranthes bidentata Blume (ABB), were added into the original EZF formula to obtain two new Jiawei-EZF (JW-EZF) preparations. To clarify the effect of the compatibility of herbs for original formulas, the chemical constituents and bioactive compounds in vivo were detected. Methods: An efficient and sensitive targeted and untargeted UHPLC/ESI-Q-Orbitrap MS method, together with mass defect filter and precursor ion list, was established firstly for the profiling of different EZF formulas. Furthermore, eleven absorbed compounds (apigenin, luteoloside, luteolin, oleuropein, wedelolactone, acteoside, specnuezhenide, 11-methyloleoside, ecliptasaponin A, formononetin, and β-ecdysone) were simultaneously quantified in rat plasma. Results: A total of 124, 162, and 177 compounds were identified or tentatively identified in EZF, JW-3-EZF (EZF+SC) and JW-4-EZF (EZF+SC+ABB), respectively. 110 compounds were found to be common constituents in the three formulas. Moreover, 66 prototypes were unambiguously identified in the rats' plasma after oral administration of the three formulas using the same strategy. 11 out of the 66 absorbed components were simultaneously quantitated in the pharmacokinetic (PK) study. Compared to the original EZF, the plasma AUC(0-24h) and AUC(0-∞) of apigenin, 11-methyloleoside, luteolin, luteoloside, wedelolactone, and acteoside were found to be significantly increased after oral administration of JW-3-EZF, and plasma AUC(0-24h) and AUC(0-∞) of apigenin, wedelolactone, and acteoside, were also found to be significantly increased after JW-4-EZF administration. Conclusion: The combined qualitative and quantitative methods were used to provide a potential approach to the characterization and quality control of the Traditional Chinese Medicine (TCM) and its preparations.