Diversity supplement for R01DE029479-01A1 to support Dr. Jeremy Elias

摘要：在当今的微生物时代，众所周知，龋病是最普遍和最昂贵的疾病之一 世界范围内的慢性传染病，由口腔微生物区系和口腔环境的失调引起 导致牙齿损伤的变化。具体地说，经常摄入可发酵的碳水化合物会促进 微生物组成逐渐向产酸和耐酸物种转移。连续不断的酸- 诱导脱矿最终克服了唾液的缓冲能力和抗微生物特性， 导致不可逆转的牙齿破坏。这项拟议研究的目标是通过以下方式预防龋齿 产酸菌的靶向治疗(t-TAB)。T-TAB将促进健康的微生物群落 在调节酸碱度和防止酸引起的牙齿损伤方面至关重要。T-TAB将通过选择性地实现 通过增强抗菌剂(AM)的效力来抑制致龋菌的生长 与共生物种相比，加速/加重了导致龋齿的酸的产生。我们提出四个建议 具体目标是开发、确定和评估有效的t-TAB候选者。在具体目标1中，我们将综合 并表征了六种新的pH敏感的季铵盐(pH-QPS)。我们希望能鉴定出化合物 或在水混合物中提供t-TAB的化合物的组合。我们将增进对 PH-QPS(S)的化学结构/AM药效关系及对AM药效和溶解度的优化 获得安全有效的t-TAB治疗。在具体目标2中，我们将授权一种经过临床测试的AM制剂， 氯己定(CHX)，具有pH敏感型AM效力(pH-AM-E)，并将其转化为t-TAB试剂。我们会 QPS功能化介孔二氧化硅包埋CHX实现酸促进CHX释放 纳米粒子。我们还将确定CHX和pH-QPS之间的相互作用所产生的协同作用。在……里面 具体目标3，我们将通过以下方式评估和比较目标1和目标2的潜在候选人的t-TAB效率 采用模拟人类口腔微生物群落的多物种生物膜模型(名为O-Mix)。这个T- TAB的疗效将在有无蔗糖的情况下进行评估，蔗糖是一种致龋性饮食碳水化合物。 战略将需要评估生物量、分析微生物谱和确定环境pH值。最后， 成功抑制产龋酸细菌生长的最有效的t-TAB候选者 在保持共生物种在工作条件下，例如保持pH高于5.5的同时，将进一步 用体外人牙釉质微生物龋病模型和体内评价特异性目标4 采用了一种成熟的小鼠龋齿模型。成功完成拟议的目标将提供新的 牙科诊所用于预防/治疗龋齿的口腔冲洗材料。从这项研究中获得的知识也将 推进材料开发，防止感染和侵蚀。

Abstract: In today's microbiome era, it is well-recognized that dental caries, one of the most prevalent and costly chronic infectious diseases world-wide, results from dysbiosis of the oral microbiota and the oral environmental changes that cause tooth damage. Specifically, frequent intake of fermentable carbohydrates promotes a progressive shift in microbial composition toward acidogenic and acid-tolerant species. The continual acid- induced demineralization eventually overcomes the buffering capacity and anti-microbial properties of saliva, leading to irreversible tooth destruction. The goal of this proposed research is to prevent dental caries through targeted treatment of acid-producing bacteria (t-TAB). t-TAB will facilitate a healthy microbial community that are vital in modulating pH and preventing acid-induced teeth damage. The t-TAB will be achieved by selectively inhibiting the growth of cariogenic bacteria through enhanced antimicrobial (AM) efficacy in response to the accelerated/aggravated caries-causing acid production in comparison to commensal species. We propose four specific aims to develop, identify and assess the effective t-TAB candidates. In Specific Aim 1, we will synthesize and characterize six new pH-sensitive quaternary pyridinium salts (pH-QPSs). We expect to identify compounds or combinations of compounds that provide t-TAB in aqueous mixtures. We will enhance our understanding of the chemical structure/AM efficacy relationship and optimize the AM efficacy and solubility of pH-QPS(s) to obtain safe and effective t-TAB treatment. In Specific Aim 2, we will empower a clinically tested AM agent, chlorhexidine (CHX), with pH-sensitive AM efficacy (pH-AM-E) and transform it into a t-TAB agent. We will achieve acid enhanced CHX release through encapsulated CHX in QPS-functionalized mesoporous silica nanoparticles. We will also identify the synergistic pH-AM-E induced by interactions of CHX and pH-QPSs. In Specific Aim 3, we will assess and compare the t-TAB efficacy of lead candidates from Aim 1 and Aim 2 by employing a multispecies biofilm model that simulates human oral microbial community (named O-mix). The t- TAB efficacy will be assessed in the presence and absence of sucrose—the cariogenic dietary carbohydrate. Strategy will entail evaluating biomass, analyzing microbial profiles and determining environmental pH. Finally, the most effective t-TAB candidates that successfully inhibit the growth of cariogenic acid-producing bacteria while keeping the commensal species in working conditions, e.g., maintaining pH above 5.5, will be further assessed in Specific Aim 4 in vitro using an in vitro microbial-caries model on human enamel and in vivo employing a well-developed mouse caries model. Successful completion of the proposed aims will provide new materials for oral rinse in dental clinics to prevent/treat dental caries. Knowledge gained from this study will also advance material development to prevent infection and erosion.