State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.
State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China; Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Yujinxiang Street 573, Changchun, Jilin, 130122, China.
J Ethnopharmacol. 2022 Oct 28;297:115571. doi: 10.1016/j.jep.2022.115571. Epub 2022 Jul 20.
Genkwa flos (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.
Traditional Chinese Medicine (TCM) is presumed to be of immense potential against pathogens infection. Whereas, the potential efficacy and mechanisms of Genkwa flos against L. monocytogenes infection has not been extensively explored. The present study aimed to identify the bioactive ingredients of Genkwa flos against L. monocytogenes infection and to delineate the underlying mechanisms of action.
Bioinformatics approach at protein network level was employed to investigate the therapeutic mechanisms of Genkwa flos against L. monocytogenes infection. And hemolysis inhibition assay, cytoprotection test, western blotting, oligomerization assay and molecular docking analysis were applied to substantiate the multiple efficacies of Genkwa flos and the bioactive ingredient genkwanin. Histopathological analysis and biochemistry detection were conducted to evaluate the in vivo protective effect of genkwanin.
Network pharmacology and experimental validation revealed that Traditional Chinese Medicine (TCM) Genkwa flos 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 promote 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.
Our study demonstrated that Genkwa flos is a potential anti-L. monocytogenes TCM, highlighted the therapeutic potential of Genkwa flos active ingredient genkwanin by targeting the pore-forming cytolysin LLO and acting as a promising antioxidative candidate against L. monocytogenes infection.
芫花（yuanhua 的中文名称），是瑞香科植物芫花 Daphne genkwa Siebold & Zucc. 的干燥花蕾，作为一种传统草药，广泛用于治疗炎症相关症状和疾病，具有利尿、化痰和止咳的功效。
传统中药（TCM）被认为具有巨大的抗病原体感染潜力。然而，芫花对单核细胞增生李斯特菌感染的潜在疗效和机制尚未得到广泛探索。本研究旨在确定芫花抗单核细胞增生李斯特菌感染的生物活性成分，并阐明其作用机制。
采用蛋白质网络水平的生物信息学方法研究芫花抗单核细胞增生李斯特菌感染的治疗机制。并应用溶血抑制试验、细胞保护试验、Western blot 分析、寡聚化试验和分子对接分析来证实芫花和其生物活性成分芫花素的多种功效。进行组织病理学分析和生化检测来评估芫花素的体内保护作用。
网络药理学和实验验证表明，传统中药芫花具有抗单核细胞增生李斯特菌的作用，并发现其能抑制 LLO 的溶血活性。生物活性成分芫花素通过与活性残基 Tyr414、Tyr98、Asn473、Val100、Tyr440 和 Val438 结合，干扰 LLO 的孔形成活性，从而减轻 LLO 介导的细胞毒性。与生物信息学预测一致，暴露于芫花素可上调 Nrf2 水平并促进 Nrf2 的易位。在体内，芫花素（80mg/kg）口服给药可显著保护免受全身单核细胞增生李斯特菌感染，表现为髓过氧化物酶（MPO）和丙二醛（MDA）水平降低、小鼠存活率提高 30%以及病原体定植减少。
本研究表明芫花是一种潜在的抗单核细胞增生李斯特菌的中药，突出了芫花的活性成分芫花素的治疗潜力，该成分通过靶向孔形成细胞毒素 LLO 并作为一种有前途的抗单核细胞增生李斯特菌感染的抗氧化候选物。
