黄芩苷对粪肠球菌毒力因子作用的体外研究

摘要

AIM:To investigate the effect of baicalin on Enterococcus faecalis (E.faecalis)biofilm growth and on the expression of its virulence genes Asa1 ,EfaA and ebpA.METHODS:Enterococcus faecalis biofilm was grown on 6 well culture plate.E.faecalis biofilm was exposed to different concentrations of baicalin solution for 24 h, then bacterial growth was observed by confocal laser scanning microscope (CLSM).The mRNA expression of virulence genes Asa1 ,EfaA and ebpA was determined by RT-PCR.RESULTS:CLSM results showed that baicalin decreased the vitality of E.faecalis in the biofilm.RT-PCR results showed that 8 mg/mL of baicalin inhibited the mRNA expres-sion of Asa1 ,EfaA and ebpA.CONCLUSION:Baicalin can inhibit Enterococcus faecalis biofilm growth,as well as the mRNA expression of Asa1 ,EfaA and ebpA.%目的：研究黄芩苷对体外粪肠球菌生物膜的抑菌效果，并探讨黄芩苷对粪肠球菌毒力因子asal、EfaA、ebpA基因转录表达水平的影响。方法：6孔板建立粪肠球菌体外生物膜模型，利用激光共聚焦显微镜观察不同浓度黄芩苷作用24 h后的抑菌效果；然后再根据抑菌效果，选择适宜浓度（2、4、8 mg/mL）的黄芩苷分别与粪肠球菌共同培养12 h，并利用RT-PCR技术检测各组粪肠球菌毒力因子asal、EfaA、ebpA的表达水平。结果：激光共聚焦显微镜观察显示：黄芩苷对粪肠球菌生物膜的抑菌作用随药物浓度的增加而增加，8 mg/mL时，生物膜内的活菌比例下降最明显；RT-PCR检测显示：与阴性对照组相比，2、4、8 mg/mL的黄芩苷均能明显抑制asal、EfaA、ebpA基因的表达（P＜0．05），其抑制作用随浓度增加而增加，各浓度组两两相比均有统计学差异（P＜0．05）。结论：黄芩苷对粪肠球菌生物膜及其毒力因子asal、EfaA、ebpA均有明显的抑制作用。