Uncovering the efficacy and mechanisms of Genkwa fios and bioactive ingredient genkwanin against L. monocytogenes infection

Ethnopharmacological relevance: Genkwa fios (yuanhua in Chinese), the dried flower buds of the plant Daphne genkwa Siebold & Zucc., as a traditional herb widely used for the treatment of inflammation-related symptoms and diseases, with the efficacies of diuretic, phlegm-resolving and cough suppressant.Aim of the study: Traditional Chinese Medicine (TCM) is presumed to be of immense potential against pathogens infection. Whereas, the potential efficacy and mechanisms of Genkwa fios against L. monocytogenes infection has not been extensively explored. The present study aimed to identify the bioactive ingredients of Genkwa fios against L. monocytogenes infection and to delineate the underlying mechanisms of action.Materials and methods: Bioinformatics approach at protein network level was employed to investigate the ther-apeutic mechanisms of Genkwa fios against L. monocytogenes infection. And hemolysis inhibition assay, cyto-protection test, western blotting, oligomerization assay and molecular docking analysis were applied to substantiate the multiple efficacies of Genkwa fios and the bioactive ingredient genkwanin. Histopathological analysis and biochemistry detection were conducted to evaluate the in vivo protective effect of genkwanin.Results: Network pharmacology and experimental validation revealed that Traditional Chinese Medicine (TCM) Genkwa fios exhibited anti -L. monocytogenes potency and was found to inhibit the hemolytic activity of LLO. Bioactive ingredient genkwanin interfered with the pore-forming activity of LLO by engaging the active residues Tyr414, Tyr98, Asn473, Val100, Tyr440 and Val438, and thereby attenuated LLO-mediated cytotoxicity. Consistent with the bioinformatics prediction, exposed to genkwanin could upregulate the Nrf2 level and pro-mote the translocation of Nrf2. In vivo, genkwanin oral administration (80 mg/kg) significantly protected against systemic L. monocytogenes infection, as evidenced by reduced myeloperoxidase (MPO) and malondialdehyde (MDA) levels, increased mice survival rate by 30% and decreased pathogen colonization.Conclusion: Our study demonstrated that Genkwa fios is a potential anti -L. monocytogenes TCM, highlighted the therapeutic potential of Genkwa fios active ingredient genkwanin by targeting the pore-forming cytolysin LLO and acting as a promising antioxidative candidate against L. monocytogenes infection.