Regulation of intestinal development by a Lactobacillus GG-derived protein

乳杆菌 GG 衍生蛋白对肠道发育的调节

• 批准号: 9269404
• 负责人: FANG YAN
• 金额: $ 39.5万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9269404
• 关键词: Address; Adult; Apoptosis; Biological Assay; Biological Preservation; Cell Line; Cell Proliferation; Child; Clinical; Colitis; Colon; DTR gene; Data; Development; Disease; Disintegrins; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cell Proliferation; Epithelial Cells; Gastrointestinal tract structure; Genes; Growth; Health; Human; Hydrogels; Immune; Immune system; Immunocompromised Host; Individual; Inflammation; Injury; Interleukin-9; Interruption; Intestines; Knowledge; Lactobacillus; Lactobacillus casei rhamnosus; Life; Ligands; Mediating; Metalloproteases; Mucins; Mus; Nature; Neonatal; Nutrient; Nutritional; Organ Culture Techniques; Pectins; Persons; Physiological; Physiological Processes; Play; Predisposition; Probiotics; Production; Proteins; Publishing; Receptor Activation; Receptor Signaling; Regulation; Research; Role; Signal Pathway; Signal Transduction; Small Interfering RNA; Staging; System; Testing; Tight Junctions; Tissues; Transcriptional Regulation; Up-Regulation; Villus; Weaning; Weight Gain; Work; Zein; base; clinical application; clinical efficacy; cytokine; disorder prevention; fetal; gut microbiota; intestinal epithelium; migration; mouse model; nutrient metabolism; organ growth; postnatal; prevent; research study; response; tissue culture; transcriptome; uptake

 DESCRIPTION (provided by applicant): The symbiotic relationship between intestinal microbiota and the host plays an important role in the intestinal development. Interruption of this relationship leads to infectious and immune-mediated diseases. This underscores the importance of identifying the effects of probiotics on intestinal development and disease prevention in children. However, there are critical gaps in knowledge about mechanisms of probiotic action. The efficacy of probiotics for nutritional and clinical application remains to be convincingly established. p40, a LGG-derived protein isolated and cloned by our group, activates epidermal growth factor receptor (EGFR) and its downstream target, PI3K/Akt in intestinal epithelial cells through stimulation of EGFR ligand release. Activation of EGFR by p40 is required for inhibition of cytokine-induced apoptosis, preservation of barrier function, and enhancement of mucin production in intestinal epithelial cells. We have generated a pectin/zein hydrogel bead system to specifically delivered p40 to the colon in mouse. By using this delivery system p40 has been sown to prevent and treat experimental colitis in mice in an EGFR-dependent manner. Since activation of EGFR plays a physiological role in development, we have expanded the scope of our work to investigate the effects of p40 on intestinal development. Based on our preliminary results that LGG colonization promotes functional maturation of the intestine and decreases susceptibility to intestinal injury and colitis in adult mice, three integrated specific aims are proposed to enhance knowledge of the functional nature of p40 in regulation of intestinal development and mechanisms of the action of p40. In Specific Aim 1, the roles of p40 in intestinal functional maturation will be determined. We will use neonatal mice, human fetal intestinal organ culture, and human and mouse enteroids to determine the roles of p40 in intestinal epithelial cell proliferation, differentiation, migration,and digestive and absorptive capacities and epithelial tight junction formation. In Specific Aim 2, transcriptional targets in intestinal epithelial cells involved in p40-regulated cellular responsesto promote intestinal functional maturation will be defined. We will determine p40-regulated intestinal epithelial genes in neonatal mice and in human fetal intestinal organ culture, and verif the function of individual candidate p40-regulated genes predicted to regulate epithelial proliferation, differentiation, migration, transporters, and tight junction formation using in vitr and ex vivo assays. In Specific Aim 3, the p40- stimulated signaling pathway in intestinal epithelial cells that is required for promotion of intestinal functional maturation will be elucidaed. We will use mouse models with intestinal epithelial cell-specific deficiency of EGFR and PI3K and pharmacologic inhibition of EGFR and Akt in human fetal intestinal organ culture and enteroids to determine the requirement of EGFR and Akt activation for p40-stimulated epithelial responses and p40-regulated EGFR and Akt-dependent transcriptional targets for functional maturation. These studies will contribute new information for nutritional and clinical applications of p40 for health in children.

 描述（申请人提供）：肠道菌群与宿主之间的共生关系在肠道发育中发挥着重要作用。中断此 这种关系会导致传染病和免疫介导的疾病。这强调了确定益生菌对儿童肠道发育和疾病预防的影响的重要性。然而，关于益生菌作用机制的知识存在严重差距。益生菌的营养和临床应用功效仍有待进一步研究 令人信服地成立。 p40 是我们课题组分离和克隆的 LGG 衍生蛋白，通过刺激 EGFR 配体释放，激活肠上皮细胞中的表皮生长因子受体 (EGFR) 及其下游靶点 PI3K/Akt。 p40 激活 EGFR 是抑制细胞因子诱导的细胞凋亡、保留屏障功能和增强肠上皮细胞粘蛋白产生所必需的。我们已经生成了果胶/玉米醇溶蛋白水凝胶珠系统，可将 p40 特异性递送至小鼠结肠。通过使用这种递送系统，p40 已被用于以 EGFR 依赖性方式预防和治疗小鼠实验性结肠炎。由于 EGFR 的激活在发育中发挥着生理作用，因此我们扩大了工作范围来研究 p40 对肠道发育的影响。基于我们的初步结果，即 LGG 定植促进成年小鼠肠道功能成熟并降低对肠道损伤和结肠炎的易感性，提出了三个综合具体目标，以增强对 p40 在调节肠道发育中的功能性质和 p40 作用机制的了解。在具体目标 1 中，将确定 p40 在肠道功能成熟中的作用。我们将使用新生小鼠、人胎儿肠道器官培养物以及人和小鼠肠类来确定p40在肠上皮细胞增殖、分化、迁移、消化和吸收能力以及上皮紧密连接形成中的作用。在具体目标 2 中，将定义参与 p40 调节细胞反应以促进肠道功能成熟的肠上皮细胞中的转录靶点。我们将在新生小鼠和人胎儿肠道器官培养物中确定 p40 调节的肠上皮基因，并使用体外和离体测定验证预测调节上皮增殖、分化、迁移、转运蛋白和紧密连接形成的单个候选 p40 调节基因的功能。在具体目标 3 中，将阐明促进肠功能成熟所需的肠上皮细胞中 p40 刺激的信号通路。我们将使用肠上皮细胞特异性 EGFR 和 PI3K 缺陷以及人胎儿肠器官培养物和肠类中 EGFR 和 Akt 药理抑制的小鼠模型，以确定 p40 刺激的上皮反应和 p40 调节的 EGFR 和 Akt 依赖性转录靶标对功能成熟的 EGFR 和 Akt 激活的要求。这些研究将为营养和临床应用提供新信息 p40 有益于儿童健康。