ShaShen-MaiDong decoction attenuates bleomycin-induced pulmonary fibrosis by inhibiting TGF-β/smad3, AKT/MAPK, and YAP/TAZ pathways

Ethnopharmacological relevance: Pulmonary fibrosis (PF) is progressive and terminal lung disease, which is also the most common sequelae of Corona Virus Disease (2019) (COVID-19) survivors. Unfortunately, there is currently no cure for PF. ShaShen-MaiDong decoction (SMT), a traditional Chinese medicine, has been employed in treating various lung diseases, which may offer potential therapeutic benefits for PF. Aim of the study: To investigate the antifibrotic efficacy of SMT and its major active ingredients as well as the underlying mechanisms for treating PF. Materials and methods: Fist, we build the UPLC-MS based qualitative and quantitative profiling for the quality control of SMT. Then, the antifibrotic efficacy of SMT was investigated in bleomycin (BLM)-induced PF mice model. Network pharmacology was used to predict the mechanism and active components of SMT for the treatment of PF, which was further verified in vitro and in vivo. Results: SMT improved the weight loss and attenuated hydroxyproline, inflammatory cytokines, and collagen deposition in BLM-induced PF mice model in a dose-dependent manner. Mechanistically, as predicted by network pharmacology analysis, SMT and its active compounds (kaempferol, quercetin, and isorhamnetin) regulated the mitogen-activated protein kinase (MAPK) signaling pathways, TGF-beta/Smad signaling pathway, and YAP/TAZ signaling pathway, which was further verified in the PF mice and TGF-beta-induced A549 cell model. Moreover, SMT balanced the proportions of increased CD4+ and decreased CD8+ T cells in the peripheral blood of PF mice model. Conclusions: Considering the high mortality and complex pathogenesis of fibrotic diseases, our results provide novel evidence that SMT would be beneficial for pulmonary fibrosis therapy by modulating MAPK, TGF-beta/Smad, and YAP/TAZ signaling pathways at same time.