法尼醇对白念珠菌生物膜葡聚糖的影响及白念珠菌耐药相关性

Effect of farnesol on glucan⁃related genes in Candida albicans biofilm and the drug resistance of Candida albicans

目的探索法尼醇对白念珠菌生物膜细胞壁葡聚糖的影响及白念珠菌的耐药相关性。方法采用浓度梯度递增法诱导构建白念珠菌耐药株,KONT真菌显色MIC药敏系统鉴定耐药株模型。本实验分为对照组、法尼醇处理组和耐药株组。利用透射电镜观察各组生物膜细胞壁,通过qPCR比较分析各组葡聚糖相关基因PIR1、PHR2、BGL2和GSC1的表达。结果本实验白念珠菌耐药株模型构建成功。透射电镜观察发现,法尼醇处理后各时相白念珠菌生物膜细胞壁出现形态改变。24 h生物膜中,对照组白念珠菌生物膜细胞壁的厚度为(220.10±2.25)nm;法尼醇处理组白念珠菌细胞壁电子颗粒减少,细胞壁厚度变薄为(145.90±4.05)nm;而耐药株组白念珠菌细胞壁电子颗粒增多,细胞壁厚度增加到(299.47±3.33)nm。qPCR结果显示,与对照组相比,法尼醇处理组PIR1和PHR2表达上调(P<0.05),GSC1表达下调(P<0.05);耐药株组PHR2表达下调(P<0.05),GSC1表达上调(P<0.01)。结论法尼醇可能通过调控葡聚糖相关基因PHR2、PIR1和GSC1影响白念珠菌细胞壁的形态和结构,而细胞壁的形态和结构与白念珠菌耐药性相关。

Objective To study the effect of farnesol on the expression of glucan⁃related genes and the drug resistance in Candida al⁃bicans biofilm.Methods Drug⁃resistant strains of Candida albicans were induced by the multi⁃step method and were identified by the KONT MIC determination system.The experiment consisted of the control group,farnesol group and drug⁃resistant group.The cell wall of Candida albicans biofilm in each group was observed by transmission electron microscope(TEM).The expression of glucan⁃related genes PIR1,PHR2,BGL2 and GSC1 in each group was analyzed by qPCR.Results The drug⁃resistant strain model of Candida albi⁃cans was successfully constructed in the experiment.TEM showed that after treatment with farnesol,the morphology of the cell wall of Candida albicans biofilm was changed.In the 24 h biofilm,the thickness of the cell wall of Candida albicans biofilm in the control group was(220.10±2.25)nm.The cell wall of the farnesol group had a reduction of electron granules,and the thickness which was(145.90±4.05)nm,was thinner than the control group.In contrast,the cell wall of the drug⁃resistant group had increased electron granules and cell wall thickness,(299.47±3.33)nm,was greater than the control group.The qPCR results showed that compared with the control group,the expression of PIR1 and PHR2 in the farnesol group was up⁃regulated(P<0.05),and GSC1 was down⁃regulated(P<0.05).Compared with the control group,the expression of PHR2 in the drug⁃resistant group was down⁃regulated(P<0.05),while GSC1 expression was up⁃regulated(P<0.01).Conclusion Farnesol may affect the morphology and structure of the cell wall of Candida albicans by regulating glucan⁃related genes PHR2,PIR1,and GSC1,and the morphology and structure of the cell wall are re⁃lated to drug resistance of Candida albicans.