Cellular Metabolomics Reveals Hepatoprotective Mechanisms of Platycoside Metabolites Against Acetaminophen-Induced Liver Injury.

Elucidating mechanisms of natural product metabolites is key to safer, more effective drugs against drug-induced liver injury (DILI). This study used cellular metabolomics to investigate hepatoprotective effects of three structurally similar platycoside metabolites-platycodigenin (PDN), 3-O-β-D-glucopyranosyl platycodigenin (OPDN), and polygalacic acid (POLA)-against APAP-induced liver injury. Using AML-12 hepatocytes challenged with APAP, intracellular metabolites were profiled by UHPLC-LTQ-Orbitrap mass spectrometry (ESI+ and ESI-), followed by PCA/OPLS-DA to identify differential metabolites and MetaboAnalyst-based pathway enrichment. All three converged on core pathways: glycerophospholipid, purine, and amino sugar/nucleotide sugar metabolism, preserving membrane integrity, mitigating oxidative stress, and modulating inflammation. Unique actions emerged: PDN/OPDN targeted sphingolipid metabolism (apoptosis regulation); OPDN/POLA enhanced glutathione and nicotinamide pathways (antioxidant defenses); OPDN exclusively regulated arachidonic acid metabolism (inflammation/immune function); POLA uniquely modulated thiamine and pentose phosphate pathways (redox/energy homeostasis). These findings highlight structural tailoring's role in diversifying mechanisms, supporting multi-component herbal paradigms, and providing a metabolomic foundation for optimized platycoside-derived DILI therapeutics.