亚甲基蓝对白色念珠菌的光动力杀伤作用

摘要

目的:探讨亚甲基蓝(MB)介导的光动力疗法(PDT)对白色念珠菌的作用,并初步研究其作用机制.方法:采用分光光度计检测MB溶液的最大吸收峰位确定MB的最适波长;通过不同浓度的MB对白色念珠菌杀伤作用确定最适MB浓度;通过予以不同的光能量光的照射,确定适宜的光能量范围,并使用荧光分子探针SOSG和HPF检测MB在不同光能量下产生的荧光量.结果:在波长660nm的光照射下,MB抗白色念珠菌作用的最适浓度为100μmol/L;0～320J/cm2的光能量范围内,光能量越高MB-PDT杀菌作用越强(P<0.05),光能量为0J/cm2的PDT组与空白对照组比较,差异无统计学意义(P>0.05);在相同光能量下,荧光分子探针SOSG所测得的MB荧光量均高于HPF的荧光测得量(均P<0.01).结论:在160～320J/cm2光能量范围内,MB介导的PDT对白色念珠菌具有较好的杀伤作用,MB杀灭白色念珠菌可能主要为PDT灭菌机制中的Ⅱ型机制.%Objective:To evaluate the effect and mechanism of methylene blue(MB) mediated photodynamic therapy(PDT) on Candida albicans.Methods:The maximum absorption peak of MB solution is detected by spectrophotometer to determine the optimal wavelength of MB.The optimal MB concentration was determined by the effect of different concentrations of MB on the killing effect of Candida albicans.The appropriate range of light energy was determined by irradiating different light energy light,and fluorescence of MB under different light energy was detected by using SOSG and HPF.Results:The optimum concentration of MB against Candida albicans was 100μmol/L at the wavelength of 660nm.The MB mediated photodynamic sterilization of Candida albicans was enhanced with the increase of the light energy from 0-320 J/ cm2(P<0.05).There was no significant difference between PDT group with light energy of 0 J/cm2 and the blank control group(P>0.05).The fluorescence amount of MB measured by SOSG was higher than that by HPF at the same light energy(P<0.01).Conclusion:Within the light energy range from 160to 320J/cm2, MB mediated PDT had a good killing effect on Candida albicans.MB killed Candida albicans mostly via the typeⅡ mechanism in the PDT sterilization mechanism.