蝎毒多肽Ctry2459抗白色念珠菌机制研究

Action mechanism of scorpion venom peptide Ctry2459 against Candida albicans

摘要:

【目的】探究蝎毒多肽Ctry2459抗白色念珠菌的作用机制。【方法】采用肉汤稀释法并结合平板计数法测定蝎毒多肽Ctry2459对白色念珠菌的最小抑菌浓度和最小杀真菌浓度；通过平板计数法绘制蝎毒多肽Ctry2459对白色念珠菌的时间-杀菌动力学曲线；通过PI吸收实验检测蝎毒多肽Ctry2459对白色念珠菌细胞膜完整性的影响；通过核酸阻滞实验检测蝎毒多肽Ctry2459与核酸间是否具有结合作用；通过流式细胞技术检测蝎毒多肽Ctry2459对白色念珠菌活性氧、线粒体膜电位以及凋亡/坏死的影响。【结果】蝎毒多肽Ctry2459对白色念珠菌的最小抑菌浓度和最小杀真菌浓度分别为25 μg/mL和50 μg/mL。蝎毒多肽Ctry2459对白色念珠菌的杀菌作用具有时间和浓度依赖性，并可通过直接破坏细胞膜的完整性以及通过ROS介导的线粒体失能导致细胞坏死的方式杀灭白色念珠菌细胞。【结论】蝎毒多肽Ctry2459可以作为抗白色念珠菌药物研发的候选分子或者分子模板。

Abstract:

[Objective] To investigate the action mechanism of scorpion venom peptide Ctry2459 against Candida albicans. [Methods] The broth microdilution and plate count methods were used to determine the minimum inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of Ctry2459 against C. albicans. Time-kill curves were drawn based on the plate count method. In addition, we evaluated the influence of Ctry2459 on the integrity of the cell membrane of C. albicans by propidium iodide (PI) absorption experiment. DNA gel retardation assay was conducted to investigate the binding effect between Ctry2459 and nucleic acid. Also, we measured the effects of Ctry2459 on the reactive oxygen species (ROS) level, mitochondrial membrane potential, and apoptosis/necrosis induction of C. albicans by flow cytometry assays. [Results] The MIC and MFC of Ctry2459 against C. albicans were 25 μg/mL and 50 μg/mL, respectively. Ctry2459 killed C. albicans in a time- and concentration-dependent manner and mainly through membrane disruption, and it could also induce C. albicans necrosis via a ROS-dependent pathway. [Conclusion] Ctry2459 had the potential for the development of anti-C. albicans drugs.