Subinhibitory Concentrations of Prim‐O‐Glucosylcimifugin Decrease the Expression of Alpha‐Hemolysin in <i>Staphylococcus aureus</i> (USA300)

Abstract

<i>Staphylococcus aureus (S. aureus)</i>, an important opportunistic pathogen in human and animal, causes a series of diseases in the impairing of immunity of host and even then death. Alpha-hemolysin (Hla), a primary virulence factor, plays a major role in the pathogenic progress of <i>S. aureus</i>, especially in pneumonia. Prim-O-glucosylcimifugin (POG), a nature chromone compound, is an active ingredient in many Chinese Medicines. In this study, POG investigated the inhibitory effect of the secretion of Hla in <i>S. aureus</i> strain USA300 at the subinhibitory concentrations. The hemolysis assays and western blotting assays showed that POG can decrease the production of Hla in the USA300 growth cell cultures in a dose-dependent manner. The results of RT-PCR revealed that reduction of Hla was related to inhibit the transcription of <i>hla</i> and <i>RNAIII</i>. In the cells experiment, POG was proved to protect A549 cells from Hla-medicated injury. In conclusion, POG was shown the capacity of decreased the production of <i>S. aureus</i> Hla. POG can be developed as a candidate agent to treat <i>S. aureus</i> infections against Hla.