Biofilm Elimination and Caries Prevention using Multifunctional Nanocatalysts

目前预防龋齿的方式是不够的，特别是当生物膜迅速积累时 在易感个体的致龋条件下，需要新的方法。在上一个供资期间， 我们研究了催化（过氧化物酶模拟物）氧化铁纳米颗粒（IONP）用于控制pH的潜力， 过氧化氢的依赖性活化作为一种新的防龋膜和防龋治疗。我们发现IONP 在致龋（酸性和富含糖）条件下显示选择性生物膜靶向和消除，同时还 减少磷灰石脱矿。体内研究表明，IONP对龋病具有高度有效性 在不影响口腔组织和口腔微生物组多样性的情况下促进口腔生长，从而证实了治疗的精确性。 我们还发现，FDA批准的IONP制剂ferumoxytol（FerIONP）显示出类似的酸性pH值。 激活牙周膜和体内防龋机制。寻找提高功效和适用性的方法 为了加强目前的治疗方式，我们测试了FerIONP与氟化物联合治疗的可能性。我们出乎意料地 发现FerIONP和氟化亚锡（SnF 2）之间的显著协同作用， 预防严重啮齿动物龋齿模型中的龋齿。在这次更新中，我们建议进一步发展这种治疗方法 方案，然后了解其作用机制以及潜在的有害影响，使用实验室， 体内和人体原位模型，以促进临床转化和产品开发。 本工作的意义在于研制出更有效、更有针对性的防龋膜和防龋剂 针对易感人群。我们假设FerIONP与SnF 2相互作用以调节两者 生物和物理化学性质，通过增加局部的生物膜作用和保护， 釉质脱矿，增强抗龋功效而不增加药剂浓度。我们将 进行剂量反应研究，以提高FerIONP/SnF 2的疗效，并评估局部和全身 体内生物学作用（目的1）。我们将评估增强型防龋膜和龋齿预防性能， 剂量对口腔肠道微生物组无有害影响或对口腔粘膜组织和重要器官无毒性。我们 将与之前的FerIONP方案（内部对照）和目前使用的抗微生物氟化物（SnF 2）进行比较。 然后，我们将研究FerIONP-SnF 2（Aim 2）的作用机制和生物分布。我们将产生 特异性FerIONP类似物，以了解生物膜靶向特异性及其与SnF 2的联合作用， 釉质结构我们将进行多组学研究，以评估对生物膜组成和功能的影响。 活性以及FerIONP通过放射性标记的生物分布。对牙釉质结构的影响将是 通过物理化学和光谱方法测定。在目标3中，我们将进一步阐明生物活性 使用具有临床相关局部治疗的人口腔内生物膜模型的改进制剂 方案.我们设想了一种可行的新技术，以靶向毒性生物膜，并预防易感人群的龋齿。 高致龋条件下的个体，这将推动产品开发和临床疗效研究。

Current modalities for preventing dental caries are insufficient, particularly when biofilms rapidly accumulate under cariogenic conditions in susceptible individuals, requiring new approaches. In the previous funding period, we studied the potential of catalytic (peroxidase mimics) iron oxide nanoparticles (IONP) for controlled, pH- dependent activation of hydrogen peroxide as a novel antibiofilm and anticaries treatment. We found that IONP displays selective-biofilm targeting and elimination under cariogenic (acidic and sugar-rich) conditions, while also reducing apatitic demineralization. In vivo studies revealed that IONP are highly effective against caries development without affecting oral tissues and the oral microbiome diversity, confirming therapeutic precision. We also discovered that an FDA-approved IONP formulation, ferumoxytol (FerIONP), displays similar acid pH- activated antibiofilm and anticaries mechanisms in vivo. In search for ways to improve efficacy and applicability to enhance current modalities, we tested the possibility of combining FerIONP with fluoride. We unexpectedly found a remarkable synergy between FerIONP and stannous fluoride (SnF2) that was exceptionally effective in preventing caries in a severe rodent caries model. In this renewal, we propose to further develop this treatment regimen, and then understand its mechanisms of action as well as potential deleterious effects using laboratory, in vivo and human in situ models to facilitate clinical translation and product development. The significance of this work is to develop a more effective and targeted antibiofilm and caries preventive approach for susceptible populations. We hypothesize that FerIONP interacts with SnF2 to modulate both biological and physicochemical properties by increasing localized antibiofilm action and protection against enamel demineralization, potentiating anticaries efficacy without increasing the concentration of agents. We will perform dose-response studies to improve the efficacy of FerIONP/SnF2 and assess local and systemic biological actions in vivo (Aim 1). We will assess enhanced antibiofilm and caries preventive performance at low doses without deleterious effects on oral-gut microbiome or toxicity on oral mucosal tissues and vital organs. We will compare with previous FerIONP regimen (internal control) and currently used antimicrobial fluoride (SnF2). Then, we will investigate the mechanisms of action and biodistribution of FerIONP-SnF2 (Aim2). We will generate specific FerIONP analogues to understand biofilm targeting specificity and their combined effects with SnF2 on enamel structure. We will perform multi-omics to assess the influence on biofilm composition and functional activities as well as biodistribution of FerIONP via radiolabeling. The impact on enamel structure will be determined via physical-chemistry and spectroscopic methods. In Aim 3, we will further elucidate the bioactivity of the improved formulations using the human intra-oral biofilm model with a clinically relevant topical treatment regimen. We envision a viable and novel technology to target virulent biofilms and prevent caries in susceptible individuals under high cariogenic conditions that will motivate product development and clinical efficacy studies.