Sanitá Paula Volpato, Pavarina Ana Cláudia, Dovigo Lívia Nordi, Ribeiro Ana Paula Dias, Andrade Mariana Carvalho, Mima Ewerton Garcia de Oliveira
Department of Dental Materials and Prosthodontics, School of Dentistry, Araraquara, São Paulo State University (UNESP), Rua Humaitá, n° 1680, Araraquara, SP, 14801-903, Brazil.
Department of Social Dentistry, School of Dentistry, Araraquara, São Paulo State University (UNESP), Rua Humaitá, 1680, Araraquara, SP, 14801-903, Brazil.
Lasers Med Sci. 2018 May;33(4):709-717. doi: 10.1007/s10103-017-2382-8. Epub 2017 Nov 13.
The purpose of this study was to evaluate the effectiveness of anti-microbial photodynamic therapy (aPDT) mediated by curcumin (Cur) associated with LED light against biofilms of Candida dubliniensis, and further, investigate cellular uptake and drug penetration through the biofilms under confocal laser scanning microscopy (CLSM). Four C. dubliniensis strains were tested: three clinical isolates from HIV-positive patients and one reference strain (CBS 7987). Biofilms were treated with three Cur concentrations (20.0, 30.0, and 40.0 μM). All samples were incubated in the dark for 20 min and exposed to a 5.28 J/cm of LED light fluence. Additional samples of each strain were treated either with Cur or LED light only. Control samples had neither Cur nor light. After aPDT, results were read using the XTT salt reduction method. The data were statistically analyzed by two-way ANOVA followed by Games-Howell post-hoc test (α = 0.05). Confocal laser scanning microscopy was used to verify both the uptake of Cur by yeast cells and its penetration through the biofilm. The results showed that aPDT promoted significant reduction on the metabolism of the biofilm-organized cells of C. dubliniensis. Further, while Cur was rapidly taken up by C. dubliniensis cells, a longer time interval was required to allow Cur penetration into biofilm cells. Based on these results, aPDT associating LED and Cur presents promising potential on fungal control of biofilms of C. dubliniensis.
本研究的目的是评估姜黄素（Cur）联合发光二极管（LED）光介导的抗菌光动力疗法（aPDT）对都柏林念珠菌生物膜的有效性，并进一步通过共聚焦激光扫描显微镜（CLSM）研究姜黄素在生物膜中的细胞摄取和药物渗透情况。测试了四株都柏林念珠菌：三株来自HIV阳性患者的临床分离株和一株参考菌株（CBS 7987）。用三种姜黄素浓度（20.0、30.0和40.0 μM）处理生物膜。所有样品在黑暗中孵育20分钟，然后暴露于5.28 J/cm²的LED光通量下。每个菌株的其他样品分别仅用姜黄素或LED光处理。对照样品既不添加姜黄素也不进行光照。aPDT处理后，使用XTT盐还原法读取结果。数据采用双向方差分析，随后进行Games-Howell事后检验（α = 0.05）进行统计分析。共聚焦激光扫描显微镜用于验证酵母细胞对姜黄素的摄取及其在生物膜中的渗透情况。结果表明，aPDT显著降低了都柏林念珠菌生物膜组织化细胞的代谢。此外，虽然都柏林念珠菌细胞能快速摄取姜黄素，但姜黄素渗透到生物膜细胞中需要更长的时间间隔。基于这些结果，LED联合姜黄素的aPDT在控制都柏林念珠菌生物膜方面具有潜在的应用前景。
