Modulation of oral microenvironment by E-cigarette aerosol mixtures

 描述(申请人提供)：电子烟(电子烟)在全球范围内日益流行。市场营销策略表明，电子烟可以被吸烟者用来帮助他们戒烟，然而，美国8所大学最近的研究表明，17%的电子烟使用者从未吸过传统香烟。每支电子烟可以提供200-400口烟，不间断，相当于2-3包香烟。尼古丁是电子烟气雾剂的主要成分，浓度高时有毒并使人上瘾。鉴于电子烟气雾剂可能含有其他有害有毒化合物，监管机构建议在对电子烟的安全性进行更好的评估和记录之前谨慎使用电子烟。电子烟气雾剂混合物最初的相互作用主要发生在口腔中，预计尼古丁和其他化合物在口腔中最活跃，接触最强烈。我们使用商用电子烟的初步数据表明，电子烟气雾剂对上皮细胞的影响是深远的。电子烟气雾剂对口腔微生物群的影响是显著的，因为我们的16S rRNA测序检测到唾液细菌谱发生了变化。与牙周健康相关的炎症介质在电子烟使用者中高于不吸烟者。此外，使用新型电子香烟气溶胶发生器(ECAG)和上皮细胞进行的体外研究表明，在首先受到牙龈卟啉单胞菌攻击然后暴露于电子烟气溶胶的细胞组中，编码细胞因子和趋化因子的转录本水平显著高于仅接触牙龈假单胞菌或牙龈假单胞菌和空气的细胞。这些数据表明，电子烟气雾剂可以通过直接作用于表膜组织和口腔微生物群来改变口腔的动态平衡。我们假设电子烟气雾剂混合物通过改变口腔微生物组的组成和增加炎症介质的表达来破坏口腔微环境的动态平衡。我们将在两个综合的特定目标下进行临床和体外机制研究。在具体目标1中，我们建议进行一项前瞻性研究，我们将招募120名年龄匹配的受试者(3组各40人：对照不吸烟者、仅吸烟者和仅电子烟使用者)，以确定电子烟气雾剂对与牙周病相关的口腔微生物群和炎症介质的影响。在具体目标2中，我们将使用带有ECAG的3D表膜组织模型来确定当受到牙周病原体的攻击时，电子烟气雾剂对表膜组织和炎症介质的影响。我们将应用新的临床和体外方法来揭示电子烟对口腔健康的影响，这将解决NIH-NIDCR的研究重点。这是第一项专门为确定微生物群和牙周病生物标记物而设计的综合性研究，用于测量和监测电子烟气雾剂混合物对健康的不利影响，并填补我们对电子烟潜在风险理解方面的空白。

 DESCRIPTION (provided by applicant): The popularity of electronic cigarettes (E-cigarettes) is increasing worldwide. Marketing strategies have suggested that E-cigarettes can be used by tobacco smokers to help them quit, however, recent studies from 8 U.S. colleges indicate that 17% of E-cigarette users had never smoked a conventional cigarette. Each E-cigarette can provide 200-400 puffs, without interruption, which is equivalent to 2-3 packs of cigarettes. Nicotine, the main ingredient in E-cigarettes aerosol and at high concentration it is toxic and addictive. Given that E-cigarette aerosol may contain other harmful toxic compounds, regulatory agencies recommend caution in the use of E-cigarettes until their safety is better evaluated and documented. The initial interaction of E-cigarette aerosol mixtures occurs largely in the oral cavity, where nicotine and other compounds are expected to be most active and the exposure is most intense. Our preliminary data using commercially available E-cigarettes, demonstrate that the effects of E-cigarette aerosol on epithelial cells are profound. The effect of E-cigarette aerosol on the oral microbiome was significant as our 16S rRNA sequencing detected a shift in the salivary bacterial profile. Inflammatory mediators associated with periodontal health were higher in E-cigarette users than in nonsmokers. Furthermore, in vitro studies using a novel Electronic Cigarette Aerosol Generator (ECAG) and epithelial cells demonstrated that levels of transcripts that encode cytokines and chemokines were significantly higher in the group of cells which were first challenged by Porphyromonas gingivalis and then exposed to the E-cigarette aerosol than in cells exposed to either P. gingivalis only or P. gingivalis and air. These data suggest that E-cigarette aerosol can alter the homeostasis of the oral cavity through its direct effects on epigingival tissue and the oral microbiome. We hypothesize that E-cigarette aerosol mixtures disrupts the homeostasis of the oral microenvironment by altering the composition of the oral microbiome and increasing the expression of inflammatory mediators. We will conduct clinical and in vitro mechanistic studies in two integrated Specific Aims. In Specific Aim 1, we propose to conduct a prospective study in which we will enroll 120 age-matched subjects (40 in each of 3 groups: control nonsmokers, only tobacco smokers, and only E-cigarette users) to determine the effects of E-cigarettes aerosol on the oral microbiome and inflammatory mediators associated with periodontal disease. In Specific Aim 2, we will use a 3D epigingival tissue model with an ECAG to determine the impact of E-cigarette aerosols on epigingival tissue and inflammatory mediators when challenged by periodontal pathogens. We will apply novel clinical and in vitro approaches to reveal the oral health impact of E-cigarettes, which will address the research priorities of the NIH-NIDCR. This is the first comprehensive study designed specifically to identify microbiome and periodontal disease biomarkers for measuring and monitoring the adverse health effects of E-cigarette aerosol mixtures and for filling gaps in our understanding of the potential risks associated with E-cigarettes.