五味子甲素对粪肠球菌毒力因子作用的初步研究

The effects of Schisandrin A on the virulence factors of enterococcus faecalis

目的:研究五味子甲素对粪肠球菌生物膜的抑菌效果及其对某些毒力因子表达的影响。方法:体外建立粪肠球菌生物膜模型,分别与31.25、62.5、125、250、500μg/m L五味子甲素、仅含菌液不含药物的BHI培养基(阴性对照)、仅含BHI液体培养基的空白对照组共同培养12 h后,MTT法检测各组抑菌效果;根据抑菌效果选取适宜药物浓度(125、250、500μg/m L)与粪肠球菌共同培养24 h后,RT-PCR法检测各组粪肠球菌毒力因子srt C、esp、ebpR mRNA的表达水平。结果:五味子甲素对粪肠球菌生物膜的抑菌作用随药物浓度的增加而升高(P<0.05),其中以500μg/m L组的抑菌效果最好;125、250、500μg/m L的五味子甲素均能明显抑制srt C、esp、ebpR各毒力因子mRNA的表达,且其抑制程度均随着药物浓度的增加而增加(P<0.05),当药物浓度为500μg/m L时,可完全抑制srt C、ebpR mRNA的表达。结论:一定浓度的五味子甲素不仅能抑制生物膜状态的粪肠球菌,同时还能抑制其毒力因子srt C、esp、ebpR的表达。

AIM：To investigate the antibacterial effect of schisandrin A on Enterococcus faecalis biofilm and on the expression of the virulence factors.METHODS：Enterococcus faecalis biofilm was cultured in vitro.The Entero-coccus faecalis biofilm was co-cultured with schisandrin A at 31.25,62.5,125,250 and 500 μg/mL respectively for 12 h,MTT assay was conducted to determine the viable of Enterococcus faecalis in the biofilm.Enterococcus faecalis biofilm was co-cultured with schisandrin A at 125,250,and 500μg/mL for 24 h,then srtC,esp and ebpR mRNA was examined by RT-PCR.RESUITS：Schisandrin A showed a dose-dependent inhibitory effect on Enterococcus faecalis wiability（P〈0.05）.The highest inhibition was achieved at 500 μg/mL of schisandrin A.Moreover,schisandrin A decreased srtC,esp and ebpR mRNA in a concentration dependent manner（P〈0.05 ）.Schisandrin A at 500 μg/mL completely inhibited the mRNA Expression of srtC,esp,and ebpR.CONCLUSION：Schisandrin A can inhibit the proliferation of Enterococcus faecalis and the expression of virulence factors srtC,esp,and ebpR mRNA of Enterococcus faecalis.