【作者】 郑欣； 程新群； 王诗达； 程磊； 李继遥； 周学东； 徐欣；

【Author】 Xin Zheng;Xinqun Wang;Shida Wang;Lei Cheng;Jiyao Li;Xuedong Zhou;Xin Xu;Department of Cariology and Operative Dentistry,West China Hospital of Stomatology,Sichuan University;

【机构】 四川大学华西口腔医学院牙体牙髓科；

【摘要】 目的:氟化物是广泛应用的有效的抗龋药物,然而其非特异性抑菌本质限制了其成为理想的生态防龋药物。精氨酸作为口腔微生态内重要的产碱底物,可促进微生态内产碱细菌取得竞争优势。本研究拟探讨精氨酸与氟化钠联合应用对口腔微生态的影响及作用模式。方法:利用棋盘格梯度稀释实验(Checkerboard micro-dilution assays),评估精氨酸与氟化钠联用对变异链球菌(Streptococcus mutans)及血链球菌(Streptococcus sanguinis)的浮游细菌及生物膜的协同/拮抗效应;通过体外单菌种、双菌种及三菌种生物膜模型,结合荧光原位杂交(Fluorescence in situ Hybridization)、定量PCR等手段,探究精氨酸与氟化钠联用对口腔微生态影响的作用模式。结果:精氨酸与氟化钠联用能够协同抑制变异链球菌的生长及生物膜形成;在多菌种生物膜中,精氨酸与氟化钠联用可以协同促进血链球菌获得竞争优势;适宜浓度组合的精氨酸与氟化钠可维持三菌种生物膜中的"链球菌优势",从而防止牙龈卟啉多胞菌(Porphyromonas gingivalis)的机会生长。结论:精氨酸与氟化物联合使用能够协同维持口腔微生态平衡。在龋病的生态防治邻域具有潜在应用价值。更多还原

【Abstract】 Objective:Fluoride is a widely used anti-caries agent,which promotes tooth hard tissue remineralization and suppresses bacterial activities.However,fluoride non-selectively suppresses oral streptococci,and thus may not be an optimal "ecological cure" for dental caries.Here we propose that arginine may improve the ecological benefit of fluoride by enriching alkali-generating bacteria in the plaque biofilm,and thus synergizes with fluoride in controlling dental caries in a more ecological approach.Methods:We assessed the antimicrobial effects of the NaF/arginine combination on the growth and biofilm formation of Streptococcus mutans and Streptococcus sanguinis with checkerboard micro-dilution assays.The optimal NaF/arginine combinations were selected and their ecological benefits on microbial equilibrium were further examined in single-,dual- and three-species biofilm using bacterial species-specific fluorescence in situ hybridization and quantitative PCR.Results:We found that arginine synergized with fluoride in suppressing acidogenic Streptococcus mutans in either planktonic or biofilm cultures.In addition,the NaF/arginine combination synergistically reduced S.mutans but enriched S.sanguinis within the multi-species biofilms compared to each agent used alone.More importantly,optimal combination of NaF/arginine maintained a "streptococcal pressure" against the potential growth of oral anaerobe Porphyromonas gingivalis within the alkalized biofilm.Conclusion:The combination application of fluoride and arginine has a potential synergistic effect in maintaining a healthy oral microbial equilibrium,and thus represents a promising ecological approach to caries management更多还原