PDF(Pubmed)
Abstract：
Dental caries is a global health problem that requires better prevention measures. One of the goals is to reduce the prevalence of the cariogenic Gram-positive bacterium Streptococcus mutans. We have recently shown that naturally occurring arachidonic acid (AA) has both anti-bacterial and anti-biofilm activities against this bacterium. An important question is how these activities are affected by other anti-bacterial compounds commonly used in mouthwashes. Here, we studied the combined treatment of AA with chlorhexidine (CHX), cetylpyridinium chloride (CPC), triclosan, and fluoride. Checkerboard microtiter assays were performed to determine the effects on bacterial growth and viability. Biofilms were quantified using the MTT metabolic assay, crystal violet (CV) staining, and live/dead staining with SYTO 9/propidium iodide (PI) visualized by spinning disk confocal microscopy (SDCM). The bacterial morphology and the topography of the biofilms were visualized by high-resolution scanning electron microscopy (HR-SEM). The effect of selected drug combinations on cell viability and membrane potential was investigated by flow cytometry using SYTO 9/PI staining and the potentiometric dye DiOC2(3), respectively. We found that CHX and CPC had an antagonistic effect on AA at certain concentrations, while an additive effect was observed with triclosan and fluoride. This prompted us to investigate the triple treatment of AA, triclosan, and fluoride, which was more effective than either compound alone or the double treatment. We observed an increase in the percentage of PI-positive bacteria, indicating increased bacterial cell death. Only AA caused significant membrane hyperpolarization, which was not significantly enhanced by either triclosan or fluoride. In conclusion, our data suggest that AA can be used together with triclosan and fluoride to improve the efficacy of oral health care.
摘要：
龋齿是一个全球性的健康问题，需要更好的预防措施。目标之一是降低致龋革兰氏阳性细菌变形链球菌的患病率。我们最近表明，天然存在的花生四烯酸（AA）对这种细菌具有抗菌和抗生物膜活性。一个重要的问题是这些活性如何受到漱口水中常用的其他抗菌化合物的影响。这里,我们研究了氯己定（CHX）联合治疗AA，氯化十六烷基吡啶（CPC），三氯生,和氟化物。进行棋盘微量滴定测定以确定对细菌生长和活力的影响。使用MTT代谢测定对生物膜进行定量，结晶紫（CV）染色，和通过旋转圆盘共聚焦显微镜(SDCM)观察用SYTO9/碘化丙啶(PI)的活/死染色。通过高分辨率扫描电子显微镜（HR-SEM）可视化细菌形态和生物膜的形貌。通过使用SYTO9/PI染色和电位染料DiOC2（3）的流式细胞术研究了所选药物组合对细胞活力和膜电位的影响，分别。我们发现CHX和CPC在一定浓度下对AA有拮抗作用，同时观察到三氯生和氟化物的加性效应。这促使我们研究AA的三重治疗，三氯生,和氟化物，比单独使用化合物或双重治疗更有效。我们观察到PI阳性细菌的百分比增加，表明细菌细胞死亡增加。只有AA引起明显的膜超极化，三氯生或氟化物都没有显着增强。总之,我们的数据表明,AA可以与三氯生和氟化物一起使用,以提高口腔保健的疗效.
