Metagenomic Study of the Periodontal Microbiome in Healthy and Diabetic Subjects

描述（由申请人提供）：2型糖尿病（T2D）是美国人群中一种重要且日益流行的疾病。此外，西班牙裔人的糖尿病患病率几乎是非西班牙裔人的两倍。糖尿病还与牙周炎的患病率和进展的增加相关。缺乏对2型糖尿病患者（T2D）牙周炎相关微生物组的综合分析，这使得我们对牙周微生物组在该人群牙周炎中的作用的理解存在重大差距。已知T2D中的宿主免疫应答被改变，并且有证据表明结缔组织代谢失调。在牙周组织中，这些变化可能是由相关微生物组引起的，也可能是其影响。我们将在高危西班牙裔人群中调查与牙周病和糖尿病相关的微生物组。我们假设与T2Ds中慢性牙周炎相关的龈下微生物组含有构成宏基因组特征的细菌种类和遗传元件（基因、代谢途径、插入序列或致病岛），所述宏基因组特征不同于全身健康受试者中的慢性牙周炎，或患有或不患有T2Ds的受试者中的已解决的牙周炎或牙周健康。我们进一步假设，与非糖尿病患者相比，T2D慢性牙周炎患者对初始牙周治疗的反应在减少或消除与发病机制相关的物种和遗传因素方面效果较差。为了验证这些假设，我们将对患有或不患有T2D的牙周炎受试者的龈下样本进行深层16S rDNA分析（目的1）。对照将包括牙周健康和牙周治疗（已解决的牙周炎）的受试者，有或没有T2D。我们还将对来自患有或不患有T2D（Aim 2）的牙周炎患者的龈下样品与如上所述的对照进行深度宏基因组序列分析。最后，我们将验证目标2中发现的来自牙周健康和患病受试者（有或无T2D）的不同样本集的顶部和毒性相关宏基因组特征差异。我们将评估细菌宏基因组标记分子在宏基因组和元转录组中的相对丰度（目的3）。这项研究将定义微生物群落和宏基因组特征，以区分与2型糖尿病患者慢性牙周炎相关的龈下微生物组与高危西班牙裔人群中全身健康患者的龈下微生物组。这项研究将解决我们在牙周炎高危人群中牙周微生物组知识的根本差距，并可能导致进一步研究开发诊断，预防和管理糖尿病疾病的创新临床方法。 公共卫生相关性：2型糖尿病（T2D）是美国人群中的一种重要且日益流行的疾病，特别是在西班牙裔人群中，并且还与牙周微生物引起的牙龈（牙周）疾病的患病率和进展的增加相关。本研究将全面表征患有或不患有T2D的受试者的牙周微生物群。这些发现将解决我们对牙周炎病因学的理解中的一个根本性差距，并可能导致诊断，预防和管理牙周炎的创新策略。

DESCRIPTION (provided by applicant): Type 2 diabetes (T2D) is a significant and increasingly prevalent disease in the US population. In addition, the prevalence of diabetes among Hispanics is nearly twice that of non-Hispanics. Diabetes is further associated with an increase in the prevalence and progression of periodontitis. Comprehensive analysis of the microbiome associated with periodontitis in type 2 diabetics (T2Ds) is lacking, leaving a significant gap in our understanding of the role of the periodontal microbiome in periodontitis in this population. The host immune response in T2Ds is known to be altered and evidence suggests a dysregulation in connective tissue metabolism. In the periodontal tissues these changes may result from, as well as impact, the associated microbiome. We will investigate the microbiome associated with periodontal disease and diabetes in a high- risk Hispanic population. We hypothesize that the subgingival microbiome associated with chronic periodontitis in T2Ds harbors bacterial species and genetic elements (genes, metabolic pathways, insertion sequences or pathogenicity islands) constituting a metagenomic signature that is distinct from that of chronic periodontitis in systemically healthy subjects, or resolved periodontitis or periodontal health in subjects with or without T2Ds. We further hypothesize that the response to initial periodontal treatment in chronic periodontitis of T2Ds will be less effective in reducing or eliminating species and genetic elements associated with pathogenesis as compared that of non-diabetic patients. To test these hypotheses we will conduct deep 16S rDNA analyses on subgingival samples from periodontitis subjects with or without T2D (Aim 1). Controls will include periodontally healthy and periodontally treated (resolved periodontitis) subjects with or without T2D. We will additionally conduct deep metagenomic sequence analysis on subgingival samples from periodontitis patients with or without T2D (Aim 2) with controls as described above. Finally we will validate the top and virulence-related metagenomic signature differences found in Aim 2 in a different sample set from periodontally healthy and diseased subjects with or without T2D. We will assess the relative abundance of the bacterial metagenomic signature molecules in the metagenome and metatranscriptome (Aim 3). This study will define the microbial community and metagenomic signatures that distinguish the subgingival microbiome associated with chronic periodontitis in type 2 diabetics from those of systemically healthy patients in a high risk Hispanic population. This research will address a fundamental gap in our knowledge of the periodontal microbiome in population at high risk for periodontitis and may lead to further studies for the development of innovative clinical approaches to diagnosing, preventing and managing the disease in diabetics. PUBLIC HEALTH RELEVANCE: Type 2 diabetes (T2D) is a significant and increasingly prevalent disease in the US population, particularly among Hispanics, and is further associated with an increase in the prevalence and progression of gum (periodontal) disease caused by periodontal microorganisms. This investigation will comprehensively characterize the periodontal microbial population in subjects with or without T2D. The findings will address a fundamental gap in our understanding of the etiological agents of periodontitis and may lead to innovative strategies for diagnosing, preventing and managing periodontitis.