Song Meng, Li Li, Li Meng, Cha Yonghong, Deng Xuming, Wang Jianfeng
Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China.
Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China.
Fitoterapia. 2016 Dec;115:31-36. doi: 10.1016/j.fitote.2016.09.017. Epub 2016 Sep 28.
Streptococcus pneumoniae is an important human pathogenic bacterium that can cause various life-threatening infections. Pneumolysin (PLY), the pore-forming toxin that forms large pores in the cell membrane, is a key virulence factor secreted by S. pneumoniae that penetrates the physical defenses of the host and plays an important role in the pathogenesis of pneumococcal diseases, such as pneumonia, meningitis, bacteremia and otitis media. This study showed that apigenin, one of the bioflavonoids widely found in herbs, inhibits PLY-induced hemolysis by inhibiting the oligomerization of PLY and has no anti-S. pneumoniae activity. In addition, when PLY was incubated with human alveolar epithelial (A549) cells, apigenin could effectively alleviate PLY-mediated cell injury. In vivo studies further demonstrated that apigenin could protect mice against S. pneumoniae pneumonia. These results imply that apigenin could directly interact with PLY to decrease the pathogenicity of S. pneumoniae and that novel therapeutics against S. pneumoniae PLY might provide greater effectiveness in combatting S. pneumoniae pneumonia.
肺炎链球菌是一种重要的人类致病细菌，可导致各种危及生命的感染。肺炎溶血素（PLY）是一种在细胞膜上形成大孔的成孔毒素，是肺炎链球菌分泌的关键毒力因子，它能穿透宿主的物理防御屏障，在肺炎球菌疾病（如肺炎、脑膜炎、菌血症和中耳炎）的发病机制中起重要作用。本研究表明，芹菜素是一种在草药中广泛存在的生物类黄酮，它通过抑制PLY的寡聚化来抑制PLY诱导的溶血，且无抗肺炎链球菌活性。此外，当PLY与人肺泡上皮（A549）细胞孵育时，芹菜素可有效减轻PLY介导的细胞损伤。体内研究进一步证明，芹菜素可保护小鼠免受肺炎链球菌肺炎的侵害。这些结果表明，芹菜素可直接与PLY相互作用以降低肺炎链球菌的致病性，针对肺炎链球菌PLY的新型疗法可能在对抗肺炎链球菌肺炎方面提供更高的疗效。
