Evaluation of Biological Mechanisms of Quanduzhong Capsule for Treating Osteoporosis by Integrating Untargeted Metabolomics and Network Pharmacology

Abstract Osteoporosis (OP) is a metabolic disease characterized by bone formation and resorption disturbances. Quanduzhong Capsule (QDZC) is a common treatment for OP in China; however, the effective components and metabolites of the drug after oral administration remain largely unknown. This study aims to identify the active components, analyze the metabolite changes, and investigate the underlying mechanism against OP. In the study, ovariectomy-induced rat OP model was established, then treated with QDZC. Alendronate sodium tablets (ASTs) were used as a reference drug. The chemical constituents of QDZC were analyzed by UPLC-QTOF-MS (ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry) and network pharmacology. The metabolomics was used to analyze differences in serum metabolites of rats in different groups [Sham, Model, Model + QDZC, and Model + AST] at 4, 8, and 12 weeks. Body weight and bone mineral density (BMD) were assessed. Enzyme-linked immunosorbent assay was used to determine serum levels of Akt, p-Akt, ERK, and p-ERK. Our data suggested 86 different chemicals from QDZC, including nine core compounds. QDZC significantly regulated 25 biomarkers linked to arachidonic acid metabolism and unsaturated fatty acid biosynthesis, and promoted serum expression of Akt, p-Akt, ERK, and p-ERK. QDZC might act by activating PI3K-Akt and MAPK signaling pathways. In addition, QDZC may use arachidonic acid derivatives to inhibit osteoclast generation and bone resorption and enhance calcitriol formation to improve calcium absorption and increase bone mass.