title: Puerarin protects against Staphylococcus aureus-induced injury of human alveolar epithelial A549 cells via downregulating alpha-hemolysin secretion.
abstract: Alpha-hemolysin, a secreted pore-forming toxin, plays an indispensable role in the pathogenicity of Staphylococcus aureus. In this study, the antimicrobial activity of puerarin against S. aureus was investigated; as a result, puerarin showed no influence on the growth of this organism. However, hemolysis and western blotting assays showed that puerarin concentration dependently inhibited the secretion of alpha-hemolysin at low concentrations. Real-time RT-PCR assay was further employed to evaluate the transcriptional level of hla, the gene encoding alpha-hemolysin, and RNAIII, an effector molecule of the agr system. The results indicated that the RNAIII expression and subsequent hla transcription were also inhibited by puerarin in a dose-dependent manner. Furthermore, puerarin significantly prevented human alveolar epithelial A549 cells from S. aureus-induced injury. Thereby, puerarin may be considered as a potential candidate for the development of antivirulence drugs in the treatment of S. aureus-mediated infections.
authors.affiliation: 1 College of Animal Husbandry and Veterinary, Liaoning Medical University , Jinzhou, China .
authors.forename: Feng
authors.initials: F
authors.lastname: Tang
authors.forename: Wen-Hua
authors.initials: WH
authors.lastname: Li
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhou
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Liu
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.forename: Yu-Shun
authors.initials: YS
authors.lastname: Tang
authors.forename: Xu
authors.initials: X
authors.lastname: Kou
authors.forename: Shu-De
authors.initials: SD
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Bao
authors.forename: Lian-Da
authors.initials: LD
authors.lastname: Qu
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.forename: Bing
authors.initials: B
authors.lastname: Li
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D002460:Cell Line; D004847:Epithelial Cells / Q000187:drug effects / Q000382:microbiology; D004912:Erythrocytes / Q000187:drug effects / Q000382:microbiology; D006460:Hemolysin Proteins / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000378:metabolism; D006461:Hemolysis / Q000187:drug effects*; D006801:Humans; D007529:Isoflavones / Q000302:isolation & purification / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011817:Rabbits; D020545:Respiratory Mucosa / Q000187:drug effects / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D007529:Isoflavones; D010936:Plant Extracts; C021091:staphylococcal alpha-toxin; C033607:puerarin