Ai Da Lotion improves eczema lesions via modulation of the JAK1/STAT3 pathway and regulation of apoptosis and oxidative stress
Introduction: Ai Da Lotion is widely used for eczema in the clinic; however, its active ingredients and molecular mechanism remain unclear. Objective: We set out to define the molecular basis for how Ai Da Lotion—a compound traditional Chinese medicine preparation—acts to treat eczema, with the goal of generating sound scientific support for its clinical use and modern translational development. Methods: In this study, we combined ultra high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry profiling with network pharmacology and molecular docking to identify the formula’s bioactive constituents and key targets, then validated these findings in keratinocyte-based models of eczema. Results: Chemical profiling identified 889 constituents, and physicochemical screening narrowed these to 42 candidate active compounds. Target network analysis uncovered 37 core nodes, with Janus kinase 1 (JAK1) and signal transducer and activator of transcription 3 (STAT3) emerging as the dominant regulatory pair. Two lead compounds—8-deoxylactucin and 6β-hydroxymethandrostenolone—bound JAK1 and STAT3 with high affinity (binding energy <−7.6 kcal/mol). Functionally, Ai Da Lotion promoted keratinocyte migration, attenuated oxidative stress, stabilized mitochondrial membrane potential, and suppressed Caspase-3–mediated apoptosis. These protective effects were recapitulated upon JAK1/STAT3 overexpression and blocked by selective pathway inhibition, indicating that the formula works primarily through JAK1/STAT3 modulation. Conclusion: Our results provide a mechanistic basis for Ai Da Lotion and illustrate a practical strategy for dissecting the pharmacology of complex herbal dermatological preparations.