Integrated Network Pharmacology and Proteomics Reveal That Erxian Decoction Counteracts Postmenopausal Osteoporosis via GSTA1-Mediated Oxidative Stress Suppression.

Background

Postmenopausal osteoporosis (PMOP) is a common metabolic bone disorder characterized by disrupted bone remodeling due to estrogen deficiency. Erxian Decoction (EXD), a traditional Chinese medicine formula, has shown clinical efficacy against PMOP, but its bioactive constituents and molecular mechanisms remain elusive.

Methods

The therapeutic effects of EXD were evaluated in ovariectomized (OVX) mice using micro-CT and bone histomorphometry. Absorbed constituents of EXD were identified by UHPLC-Q analysis. Network pharmacology and quantitative proteomics were integrated to predict the key pathways and targets. The candidate target was validated by in vivo assays, including Western blot, glutathione (GSH) levels, glutathione S-transferases (GSTs) activity, malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) levels. Molecular docking was performed to assess the binding affinity between bioactive components and the target protein.

Results

EXD treatment significantly ameliorated bone microarchitecture deterioration and restored bone remodeling balance in OVX mice. A total of 137 core absorbed constituents of EXD were identified. Integrated network pharmacology and proteomics analyses revealed that EXD primarily modulates the glutathione metabolism pathway to counteract oxidative stress. Glutathione S-transferase A1 (GSTA1) was pinpointed as a potential target. In vivo experiments confirmed that EXD upregulated GSTA1 expression, restored total GSTs activity, replenished GSH reserves, and reduced MDA and 4-HNE levels. Molecular docking demonstrated stable protein-ligand interactions between bioactive components of EXD and GSTA1.

Conclusions

EXD alleviates PMOP by activating GSTA1-mediated glutathione metabolism and suppressing oxidative stress. These findings provide a mechanistic basis for the clinical application of EXD in treating PMOP.