Inflammatory Effect of Enteric Bacterial-Mediated Intestinal Permeability

肠道细菌介导的肠道通透性的炎症效应

• 批准号: 8521275
• 负责人: Ian Michael Carroll
• 金额: $ 11.94万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8521275
• 关键词: Address; Adverse effects; Affect; Antibiotics; Award; Bacteria; Bifidobacterium; Biological; Caring; Catalytic Domain; Cells; Colitis; Collaborations; Comorbidity; Complex; Crohn' s disease; Disease; Enteral; Enterobacteriaceae; Enterococcus faecalis; Epithelial; Epithelial Cells; Functional disorder; Gastrointestinal Diseases; Gelatinases; Germ-Free; Gnotobiotic; Goals; Heterogeneity; Human; Immune system; In Vitro; Individual; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Interleukin-10; Intestinal Diseases; Intestines; Knowledge; Lead; Measures; Mediating; Medical; Mentors; Mono-S; Mus; Outcome; PAR-1 Receptor; Patients; Peptide Hydrolases; Permeability; Pharmaceutical Preparations; Physiology; Probiotics; Proteinase-Activated Receptors; Public Health; Quality of life; Receptor Activation; Recurrence; Research; Resources; Serine; Serine Protease; Serine Proteinase Inhibitors; Serpins; Serum; Source; Testing; Therapeutic; Tight Junctions; Training; Treatment Cost; Ulcerative Colitis; United States; Wild Type Mouse; clinical practice; design; duodenitis; effective therapy; in vivo Model; innovation; meetings; member; microbial; monolayer; mutant; new therapeutic target; novel; novel therapeutic intervention; psychologic; success; therapeutic target

DESCRIPTION (provided by applicant): Inflammatory bowel diseases (IBD) are highly prevalent intestinal diseases in the United States affecting 1.4 million individuals. These diseases are associated with reduced quality of life and psychological co-morbidity. Current estimates for IBD associated treatment costs in the US are $6.3 billion. The high rate of recurrence and lack of safe and curative treatments for IBD underscore the need for alternate therapeutic approaches for these complex diseases. Bacterial proteases capable of inducing intestinal permeability via protease-activated receptors (PARs) present a novel therapeutic target for IBD. The goals for this proposal are to (I) elucidate the specific mechanism by which enteric bacteria induce intestinal permeability, (II) assess the biological effect of protease producing and inhibiting enteric bacteria on intestinal permeability, and (III) assess the inflammatory effect of protease producing and inhibiting enteric bacteria on the intestine. To address these goals we have proposed three specific aims. In specific aim 1 we will determine the ability of protease-producing and - inhibiting enteric bacterial strains to regulate PARs and permeability in human epithelial cells in vitro. To achieve this aim we will use wild-type and mutant Enterococcus faecalis OG1RF strains that lack gelatinase or serine protease activity, and wild-type and mutant Bifidobacterium longum ATCC15707 strains that lack serpin activity. We will expose tight junction forming T-84 epithelial cell monolayers to parental and mutant E. faecalis OG1RF and B. longum ATCC15707 strains and measure cell permeability and PAR activation. In specific aim 2 we will determine the ability of protease-producing and inhibiting enteric bacterial strains to regulate PAR- dependent intestinal permeability in gnotobiotic mice. To achieve this aim we will mono- and dual-associate germ-free wild-type and PAR deficient mice with parental and mutant bacterial strains and measure intestinal permeability and PAR activation. In specific aim 3 we will determine the ability of protease-producing and inhibiting enteric bacterial strains to induce intestinal permeability and inflammation in gnotobiotic IL-10 deficient (IL-10-/-) mice. To achieve this aim we will mono- and dual-associate germ-free wild-type and IL-10-/- mice with parental and mutant bacterial strains and measure intestinal permeability, PAR activation, and inflammation. The contribution of the proposed research is significant as it will define a precise mechanism by which enteric bacteria alter intestinal permeability and contribute to inflammation. The proposed research will also be of significance because the outcome will contribute to the broader understanding of mechanisms by which dysbiosis in the intestinal microbiota affects IBD. Additionally, the proposed research is innovative in our opinion as it will allow for the design of rational pathophysiology-directed probiotic treatment of GI disease.

描述（由申请人提供）：炎症性肠病 (IBD) 是美国非常流行的肠道疾病，影响着 140 万人。这些疾病与生活质量下降和心理共病有关。目前美国 IBD 相关治疗费用估计为 63 亿美元。 IBD 的高复发率和缺乏安全有效的治疗方法凸显了这些复杂疾病需要替代治疗方法的必要性。细菌蛋白酶能够通过蛋白酶激活受体（PAR）诱导肠道通透性，为 IBD 提供了一个新的治疗靶点。该提案的目标是（I）阐明肠道细菌诱导肠道通透性的具体机制，（II）评估产生和抑制肠道细菌对肠道通透性的生物学效应，以及（III）评估产生和抑制肠道细菌对肠道的炎症作用。为了实现这些目标，我们提出了三个具体目标。在具体目标 1 中，我们将确定产生蛋白酶并抑制肠道细菌菌株在体外调节人上皮细胞 PAR 和通透性的能力。为了实现这一目标，我们将使用缺乏明胶酶或丝氨酸蛋白酶活性的野生型和突变型粪肠球菌 OG1RF 菌株，以及缺乏丝氨酸蛋白酶抑制剂活性的野生型和突变型长双歧杆菌 ATCC15707 菌株。我们将形成紧密连接的 T-84 上皮细胞单层暴露于亲本和突变体粪肠球菌 OG1RF 和长双歧杆菌 ATCC15707 菌株，并测量细胞通透性和 PAR 激活。在具体目标 2 中，我们将确定产蛋白酶和抑制肠道细菌菌株调节 PAR 依赖性肠道通透性的能力。为了实现这一目标，我们将无菌野生型和 PAR 缺陷小鼠与亲本和突变菌株进行单和双关联，并测量肠道通透性和 PAR 激活。在具体目标 3 中，我们将确定产蛋白酶和抑制肠道细菌菌株在限生素 IL-10 缺陷 (IL-10-/-) 小鼠中诱导肠道通透性和炎症的能力。为了实现这一目标，我们将无菌野生型和 IL-10-/- 小鼠与亲本和突变菌株进行单关联和双关联，并测量肠道通透性、PAR 激活和炎症。这项研究的贡献是重大的，因为它将定义肠道细菌改变肠道通透性并导致炎症的精确机制。拟议的研究也具有重要意义，因为其结果将有助于更广泛地了解肠道微生物群失调影响 IBD 的机制。此外，我们认为拟议的研究具有创新性，因为它将允许设计合理的病理生理学导向的益生菌治疗胃肠道疾病。