Biofilm Elimination and Caries Prevention using Multifunctional Nanocatalysts

使用多功能纳米催化剂消除生物膜和预防龋齿

基本信息

批准号：
9237531
负责人：
Hyun Koo
金额：
$ 42.69万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-12-09 至 2020-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9237531
关键词：
Acids Affect Anti-Bacterial Agents Apatites Architecture Bacteria Biological Caries prevention Catalysis Cell Line Cell Survival Cells Cessation of life Chemicals Chlorhexidine Clinical Confocal Microscopy Dental Enamel Dental caries Development Dextrans Disease model Effectiveness Ensure Evaluation Exhibits Expenditure Exposure to Extracellular Matrix Face Fluorides Formulation Free Radicals Generations Gingiva Goals Gold Hardness Healthcare High Prevalence Hydrogen Peroxide In Situ In Vitro Infection Iron Lead Lesion Local Anti-Infective Agents Mechanics Medical Device Metals Microbe Microbial Biofilms Minerals Modality Modeling Mouth Diseases Mucous Membrane Oral Oral health Oral mucous membrane structure Organ Outcome Peroxidases Pharmaceutical Preparations Physiological Prevention Preventive Process Production Property Rodent Rodent Model Salts Severity of illness Structure System Testing Therapeutic Time Tissues Topical application Treatment Protocols Virulent Work anticaries antimicrobial antimicrobial drug base biomaterial compatibility biophysical techniques calcium phosphate cariogenic bacteria clinical efficacy clinical translation clinically relevant cohesion cost cytotoxic cytotoxicity demineralization drug efficacy effective therapy efficacy study fascinate improved in vivo iron oxide killings manganese chloride microCT nanomaterials nanoparticle novel strategies prevent product development soft tissue spatiotemporal technology development time use

项目摘要

Despite the high prevalence of biofilm-related oral diseases such as dental caries, there are no clinically effective therapies to disrupt virulent biofilms, resulting in >$40 billion expenditures annually in the US. Effective control of cariogenic biofilms is notoriously challenging because the bacteria are enmeshed in a protective extracellular matrix rich in exopolysaccharides (EPS). Furthermore, EPS-enmeshed bacteria create highly acidic microenvironments that promote acid-dissolution of tooth enamel, leading to the onset of dental caries. Current antimicrobial agents are incapable of disrupting the EPS matrix or affecting the physico- chemical aspects of caries and often fail to efficiently kill the microbes within biofilms, resulting in limited efficacy in vivo. To overcome these remarkable hurdles, we have developed an exciting therapeutic strategy using biocompatible iron oxide nanoparticles (IO-NP) with catalytic activity and pH-responsive properties that display both anti-biofilm and anti-caries actions. IO-NP exhibit peroxidase-like activity at acidic pH values that rapidly activates hydrogen peroxide (H2O2) in situ to simultaneously degrade the protective biofilm EPS-matrix and kill embedded bacteria with exceptional efficacy (>5-log reduction of cell viability) in 5 minutes. Moreover, IO-NP also reduce apatite demineralization in acidic conditions. We hypothesize that IO-NP synergizes with H2O2 to amplify anti-biofilm effects and prevent the onset of dental caries in vivo via nanocatalysis and enhanced in situ production of antibacterial, EPS-degrading and demineralization-blocking agents at acidic pH. The significance of this work is to develop a feasible and superior anti-biofilm and caries preventive approach compared to current chemical modalities. To test our hypothesis, we will optimize the efficacy of IO-NP/H2O2 to further improve anti-biofilm and demineralizing-blocking activities (Aim 1). We will enhance the catalytic activity of IO-NP by inclusion of specific metal salts into the nanoparticles, and explore the effects of various dextran- based coatings to increase IO-NP localization within biofilm structure. Furthermore, we will incorporate calcium-phosphate into IO-NP to enhance its effects on demineralization. Then, we will evaluate the efficacy of enhanced IO-NP/H2O2 for biofilm control in vitro using a mixed-species, cariogenic biofilm model (Aim 2). We will further elucidate the biological actions of IO-NP/H2O2 using time-lapsed confocal and biophysical methods to examine spatiotemporal degradation of EPS-matrix, bacterial killing and cohesiveness within intact biofilms. The effects on enamel demineralization will be assessed using micro-hardness and micro-CT. In Aim 3, we will evaluate the biocompatibility and efficacy of the developed IO-NP/H2O2 therapy in hindering cariogenic biofilms and the onset of carious lesions in vivo using a rodent caries model with a clinically-relevant topical treatment regimen. Successful completion of these aims will provide a framework for further formulation development and clinical efficacy studies. Importantly, IO-NP can be synthesized with low cost at large scale while H2O2 is readily available, which could lead to a feasible new anti-biofilm/anti-caries therapeutic platform for topical use.

尽管生物膜相关的口腔疾病（例如龋齿）的患病率很高，但在临床上没有有效破坏有毒生物膜的有效疗法，每年在美国造成400亿美元的支出。众所周知，有效控制商蛋白生物膜是具有挑战性的，因为细菌被嵌入富含外多糖的保护性细胞外基质（EPS）。此外，EPS添加细菌会产生高度酸性的微环境，促进牙齿牙釉质的酸排序，导致牙齿发作龋齿。当前的抗菌剂无法破坏EPS基质或影响物理龋齿的化学方面，通常无法有效地杀死生物膜内的微生物，导致有限体内功效。为了克服这些巨大的障碍，我们制定了令人兴奋的治疗策略使用具有催化活性和pH响应特性的生物相容性铁纳米颗粒（IO-NP）同时显示抗生物膜和抗卡里膜动作。 IO-NP在酸性pH值下表现出过氧化物酶样活性迅速激活过氧化氢（H2O2），以同时降解保护性生物膜EPS-MATRIX 并在5分钟内杀死具有出色的功效（细胞活力降低> 5-log降低）的嵌入细菌。而且， IO-NP还减少了酸性条件下的磷灰石去矿化。我们假设IO-NP与 H2O2可以扩增抗生物膜的作用，并通过纳米催化和在酸性pH值下，增强了抗菌，EPS降解和非矿化阻滞剂的原位产生。这项工作的意义是开发可行的抗生物膜和性含症的预防方法与当前的化学方式相比。为了检验我们的假设，我们将优化IO-NP/H2O2的功效进一步改善了抗生物膜和脱矿质封锁活动（AIM 1）。我们将增强催化活性通过将特定的金属盐纳入纳米颗粒中，并探索各种右旋基于生物膜结构中IO-NP定位的基于涂料。此外，我们将合并磷酸钙进入IO-NP，以增强其对脱矿化的影响。然后，我们将评估使用混合物种，致癌生物膜模型增强了体外生物膜对照的IO-NP/H2O2（AIM 2）。我们将进一步阐明使用时间范围的共聚焦和生物物理方法的IO-NP/H2O2的生物学作用检查完整生物膜内EPS-矩阵的时空降解，细菌杀伤和凝聚力。将使用微硬度和微观CT评估对搪瓷脱源性的影响。在AIM 3中，我们将评估开发的IO-NP/H2O2疗法在阻碍性致富生物膜中的生物相容性和功效以及使用啮齿动物龋齿模型在体内发作，并具有与临床相关的局部治疗方案。这些目标的成功完成将为进一步制定开发提供框架和临床功效研究。重要的是，IO-NP可以大规模合成，而H2O2为随时可用，这可能会导致可行的新抗生物胶片/抗卡里式治疗平台，用于局部使用。