五倍子提取物介导PDR1降低光滑念珠菌耐药性的机制研究

光滑念珠菌对氟康唑存在天然耐药性，引起的感染难治疗，导致患者的死亡率较高。降低光滑念珠菌的耐药性将有效改善患者的死亡率。本课题组前期研究及文献发现，五倍子提取物焦性没食子酸可以显著降低氟康唑对光滑念珠菌的最小抑菌浓度，但其机制尚不明确。研究表明，光滑念珠菌耐药机制主要是对唑类药物外排作用增强。我们推测焦性没食子酸是否通过影响光滑念珠菌的外排泵相关基因（CDR1、CDR2及两者的转录调控因子PDR1）的表达来降低其对氟康唑的耐药性。本课题拟利用流式细胞技术、荧光实时定量RT-PCR技术和Western Blot技术检测焦性没食子酸对CDR1、CDR2、PDR1的表达调控作用，进一步构建PDR1基因敲除株和回补株，从分子水平分析焦性没食子酸降低光滑念珠菌耐药性的作用机制，为焦性没食子酸的临床治疗提供指导，为降低现有抗生素耐药性提供研究基础。

Candida glabrata is natural tolerance to fluconazole, which causes the infection hard to be treated leading to patients’ high mortality. Reducing the resistance of Candida glabrata will improve the mortality. The literature and our preliminary research find that Galla Chinensis extract, pyrogallic acid can reduce the minimum inhibitory concentration of fluconazole against Candida glabrata, but the mechanism is not clear. Reasearches indicate that the main resistance mechanism of Candida glabrata is the enhance of excretion effect against azole drug. We speculate that pyrogallic acid reduces the resistance of Candida glabrata by affecting the expression of efflux pump gene (CDR1,CDR1 and their transcription regulation factor PDR1).We intend to observe the expression of CDR1, CDR1 and PDR1 gene regulated by pyrogallic acid through flow cytometry, Real-time PCR and Western Blot analysis, and further constructing PDR1 gene knockout strains and revertant strains to analyze the mechanism of pyrogallic acid reducing the resistance of Candida glabrata at the molecular level, which may provide guidance for the clinical treatment of pyrogallic acid and research foundation for reducing existed antibiotic drug resistance.