Department of Dental Materials and Prosthodontics, Araraquara Dental School, UNESP-Univ. Estadual Paulista, Araraquara, SP, Brazil.
Lasers Med Sci. 2013 Feb;28(2):391-8. doi: 10.1007/s10103-012-1064-9. Epub 2012 Feb 23.
Photodynamic therapy has been investigated as an alternative method of killing pathogens in response to the multiantibiotic resistance problem. This study evaluated the photodynamic effect of curcumin on methicillin-resistant Staphylococcus aureus (MRSA) compared to susceptible S. aureus (MSSA) and L929 fibroblasts. Suspensions of MSSA and MRSA were treated with different concentrations of curcumin and exposed to light-emitting diode (LED). Serial dilutions were obtained from each sample, and colony counts were quantified. For fibroblasts, the cell viability subsequent to the curcumin-mediated photodynamic therapy was evaluated using the MTT assay and morphological changes were assessed by SEM analysis. Curcumin concentrations ranging from 5.0 to 20.0 μM in combination with any tested LED fluences resulted in photokilling of MSSA. However, only the 20.0 μM concentration in combination with highest fluence resulted in photokilling of MRSA. This combination also promoted an 80% reduction in fibroblast cell metabolism and morphological changes were present, indicating that cell membrane was the main target of this phototherapy. The combination of curcumin with LED light caused photokilling of both S. aureus strains and may represent an alternative treatment for eradicating MRSA, responsible for significantly higher morbidity and mortality and increased healthcare costs in institutions and hospitals.
光动力疗法已被研究作为一种替代方法来杀死病原体，以应对多抗生素耐药问题。本研究评估了姜黄素对耐甲氧西林金黄色葡萄球菌（MRSA）与敏感金黄色葡萄球菌（MSSA）和 L929 成纤维细胞的光动力效应。MSSA 和 MRSA 的悬浮液用不同浓度的姜黄素处理，并暴露于发光二极管（LED）下。从每个样本中获得连续稀释液，并对菌落进行计数。对于成纤维细胞，用 MTT 测定法评估姜黄素介导的光动力疗法后的细胞活力，并通过 SEM 分析评估形态变化。在与任何测试的 LED 光强度组合时，浓度范围为 5.0 至 20.0 μM 的姜黄素导致 MSSA 的光杀伤。然而，只有在与最高光强度组合的 20.0 μM 浓度下才导致 MRSA 的光杀伤。这种组合还促进了 80%的成纤维细胞代谢减少，并且存在形态变化，表明细胞膜是这种光疗的主要靶标。姜黄素与 LED 光的组合导致两种金黄色葡萄球菌菌株的光杀伤，并且可能代表一种替代治疗方法，用于根除 MRSA，MRSA 导致机构和医院的发病率和死亡率显著增加，并增加了医疗保健成本。
