title: Impact of luteolin on the production of alpha-toxin by Staphylococcus aureus.
abstract: OBJECTIVE
  To investigate the influence of subinhibitory concentrations of luteolin on the production of α-toxin in Staphylococcus aureus.
  
  
  RESULTS
  The minimal inhibitory concentrations (MICs) were determined using a broth microdilution method, and the MICs of luteolin against the tested Staph. aureus strains ranged from 16 to 64 μg ml(-1). Haemolysis, Western blot and real-time reverse transcription (RT)-PCR assays were used to evaluate the effect of luteolin on Staph. aureusα-toxin secretion and on the level of gene expression, respectively. The data indicated that subinhibitory concentrations of luteolin dose dependently decreased the production of α-toxin in both meticillin-sensitive Staph. aureus (MSSA) and meticillin-resistant Staph. aureus (MRSA). Furthermore, the transcriptional levels of agr (accessory gene regulator) in Staph. aureus were also inhibited by luteolin.
  
  
  CONCLUSIONS
  Luteolin decreases the production and/or secretion of α-toxin in Staph. aureus; the reduced production may be dependent, in part, upon the luteolin-induced inhibition of the agr locus.
  
  
  CONCLUSIONS
  The findings indicate that luteolin may be used as a basis for the development of antimicrobial agents aimed at bacterial virulence factors.
authors.affiliation: Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, College of Animal Science and Veterinary Medicine, Jilin University, Changchun, China.
authors.forename: J
authors.initials: J
authors.lastname: Qiu
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: H
authors.initials: H
authors.lastname: Meng
authors.forename: C
authors.initials: C
authors.lastname: Hu
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Luo
authors.forename: J
authors.initials: J
authors.lastname: Dong
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Deng
authors.forename: X
authors.initials: X
authors.lastname: Deng
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D001427:Bacterial Toxins / Q000096:biosynthesis*; D047311:Luteolin / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D013203:Staphylococcal Infections / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000378:metabolism; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D001427:Bacterial Toxins; D037521:Virulence Factors; D010738:Type C Phospholipases; D047311:Luteolin