Universidad Nacional de Córdoba (UNC), Facultad de Ciencias Químicas, Departamento de Ciencias Farmacéuticas, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Instituto Multidisciplinario de Biología Vegetal (IMBIV), Haya de la Torre y Medina Allende, 5000, Córdoba, Argentina.
Universidad Nacional de Córdoba (UNC), Facultad de Ciencias Exactas Físicas y Naturales, Cátedra de Microbiología, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Instituto Multidisciplinario de Biología Vegetal (IMBIV), Av. Vélez Sarsfield 299, Córdoba, Argentina.
Food Chem Toxicol. 2018 Apr;114:285-291. doi: 10.1016/j.fct.2018.02.042. Epub 2018 Feb 21.
The antioxidant effect of 8PP, a prenylflavonoid from Dalea elegans on Candida albicans biofilms, was investigated. We previously reported that sensitive (SCa) and resistant C. albicans (RCa) biofilms were strongly inhibited by this compound, in a dose-depending manner (50 μM-100 μM), with a prooxidant effect leading to accumulation of endogenous oxidative metabolites and increased antioxidant defenses. In this work, the antifungal activity of high concentrations of 8PP (200-1000 μM), the cellular stress imbalance and the architecture of biofilms were evaluated. Biofilms were studied by crystal violet and confocal scanning laser microscopy (CSLM) with COMSTAT analysis. Superoxide anion radical, the activity of the superoxide dismutase and the total antioxidant capacity were measured. Intracellular ROS were detected by a DCFH-DA and visualized by CSLM; reactive nitrogen intermediates by Griess. An antioxidant effect was detected at 1000 μM and levels of oxidant metabolites remained low, with major changes in the SCa. COMSTAT analysis showed that biofilms treated with higher concentrations exhibited different diffusion distances with altered topographic surface architectures, voids, channels and pores that could change the flow inside the matrix of biofilms. We demonstrate for first time, a concentration-dependent antioxidant action of 8PP, which can alter its antifungal activity on biofilms.
我们研究了 Dalea elegans 中的一种类异戊烯黄酮 8PP 对白色念珠菌生物膜的抗氧化作用。我们之前的研究报告表明，这种化合物以剂量依赖的方式（50μM-100μM）强烈抑制敏感（SCa）和耐药（RCa）白色念珠菌生物膜的形成，具有促氧化作用，导致内源性氧化代谢物的积累和抗氧化防御的增加。在这项工作中，评估了高浓度 8PP（200-1000μM）的抗真菌活性、细胞应激失衡和生物膜的结构。使用结晶紫和共焦扫描激光显微镜（CSLM）和 COMSTAT 分析研究生物膜。通过测量超氧阴离子自由基、超氧化物歧化酶的活性和总抗氧化能力来测量生物膜的抗氧化活性。通过 DCFH-DA 检测细胞内 ROS，并通过 CSLM 可视化；通过 Griess 检测活性氮中间产物。在 1000μM 时检测到抗氧化作用，并且氧化代谢物的水平仍然较低，对 SCa 的影响最大。COMSTAT 分析表明，用更高浓度处理的生物膜表现出不同的扩散距离，改变了拓扑表面结构，出现空隙、通道和孔，这可能会改变生物膜基质内的流动。我们首次证明了 8PP 的浓度依赖性抗氧化作用，这可能会改变其对生物膜的抗真菌活性。
