小檗碱消除ESBLs大肠杆菌耐药性的研究

A study on the elimination of drug resistance of ESBLs E.coli by berberine

为了研究小檗碱消除超广谱β-内酰胺酶(ESBLs)大肠杆菌耐药性的效果,试验以3株ESBLs大肠杆菌作为研究对象,采用二倍稀释法测定小檗碱作用3株ESBLs大肠杆菌前后的MIC变化,然后采用琼脂糖凝胶电泳、ELISA法和实时荧光定量PCR方法分别检测小檗碱作用后大肠杆菌R质粒、ESBLs活性、生物被膜形成及外排系统AcrA mRNA、AcrB mRNA转录水平的变化。结果表明:3株ESBLs大肠杆菌对小檗碱的MIC均为2.00 mg/mL;经小檗碱作用后有2株ESBLs大肠杆菌对头孢噻肟的MIC从32.00 mg/mL降至8.00 mg/mL,有1株ESBLs大肠杆菌对头孢噻肟的MIC从32.00 mg/mL降至16.00 mg/mL。经小檗碱作用后有2株ESBLs大肠杆菌质粒条带消失2条,有1株ESBLs大肠杆菌质粒条带消失1条;3株ESBLs大肠杆菌的ESBLs活性均极显著降低(P<0.01),碱性磷酸酶活性均极显著升高(P<0.01);3株ESBLs大肠杆菌外排系统AcrA mRNA转录水平极显著降低(P<0.01),2株ESBLs大肠杆菌外排系统AcrB mRNA转录水平显著降低(P<0.05)。说明小檗碱对ESBLs大肠杆菌的4种耐药消除机制均具有良好的效果。

In order to study the effects of berberine on the elimination of drug resistance of E.coli with ultra-broad spectrumβ-lactamase(ESBLs),the MIC changes of 3 ESBLs E.coli strains before and after berberine treatment were measured by double dilution method.Then,the changes of R plasmid,ESBLs activity,biofilm formation and the transcription levels of AcrA mRNA and AcrB mRNA in efflux pump of E.coli after berberine treatment were detected by agalose gel electrophoresis,ELISA and real-time fluorescence quantitative PCR.The results showed that the MIC of 3 E.colis to berberine was 2.00 mg/mL.After treatment with berberine,the MIC of 2 ESBLs E.colis against cefotaxime decreased from 32.00 mg/mL to 8.00 mg/mL,and the MIC of 1 ESBLs E.colis against cefotaxime decreased from 32.00 mg/mL to 16.00 mg/mL.After treatment with berberine,the plasmid bands of 2 strains of ESBLs disappeared,and the plasmid bands of 1 strain of ESBLs disappeared.The ESBLs activity of 3 ESBLs strains was significantly decreased(P<0.01).Alkaline phosphatase activity was significantly increased(P<0.01).The transcription level of AcrA mRNA in efflux pump of ESBLs was significantly decreased in 3 strains(P<0.01),and the transcription level of AcrB mRNA in efflux pump of ESBLs was decreased in 2 strains(P<0.05).These results indicated that berberine had a good effect on the 4 drug resistance elimination mechanisms of ESBLs E.coli.