Inflammatory Bowel Disease: A Novel Therapeutic Approach

描述(申请人提供)：溃疡性结肠炎(UC)和克罗恩病(CD)是慢性、复发性胃肠道炎症性疾病，统称为炎症性肠病(IBD)。IBD的病因在很大程度上仍不清楚。据估计，美国有100万人患有IBD，其中包括儿童和青少年。IBD的发病机制通常被认为是对无处不在的非致病微生物抗原的异常免疫反应的结果。鉴于IBD的传统和新治疗方法，其副作用和高昂的成本促使人们研究新的替代治疗方式。一种这样的替代品是姜黄香料中一种众所周知的抗炎和化学预防成分，姜黄素，最近才有报道说它可以显著减轻或改善实验诱导的小鼠结肠炎。姜黄素吸收差，在胃肠道中广泛代谢，这可能解释了报道的毒性不足的原因。这项拟议项目的目的是更详细地研究姜黄素对结肠炎的保护作用机制，并为儿童和成人IBD患者的临床试验提供足够的科学背景。这将通过研究饮食姜黄素在基于免疫的结肠炎小鼠模型中的有效性来实现。将使用免疫失调倾向不同的IL-10-/-和TCRα/-小鼠(分别以Th1和Th2为主)。在宏观、形态和生化评估之后，将对结肠上皮细胞和免疫细胞的基因表达谱进行比较全基因组微阵列分析，以进一步了解姜黄素的分子靶点及其作用机制。此外，姜黄素在对照组小鼠和已建立的分化极化炎症小鼠的结肠细胞中的上皮代谢将借助于高效液相/液质联用技术进行定性和定量的分析。将利用已建立的小鼠巨噬细胞(RAW264.7)和结肠细胞(YAMC细胞)模型来评估被确认为姜黄素新代谢物的化合物的抗炎活性。为了阐明姜黄素在肠道中作用的新机制，我们将研究姜黄素对结肠抗菌隐形蛋白相关多肽表达的影响。此外，我们还将描述其在识别的独特调控基因上的作用机制，例如内毒素介导的MIP-2(小鼠IL-8同源)基因转录的早期诱导。总之，拟议的项目将提供有关姜黄素在IBD中的作用机制、其在不同极化的T细胞介导的炎症中的分子靶标以及该活性化合物在健康和发炎的结肠中的分子形式的新信息。

DESCRIPTION (provided by applicant): Ulcerative Colitis (UC) and Crohn's Disease (CD) are chronic, relapsing inflammatory disorders of the gastrointestinal tract, collectively known as Inflammatory Bowel Disease (IBD). The cause of IBD, which in U.S. affects an estimated 1 million individuals, including children and adolescents, remains largely unknown. Pathogenesis of IBD is most commonly viewed as an effect of an aberrant immune response against ubiquitous, non-pathogenic microbial antigens. In view of traditional and novel treatments of IBD, their side effects and high cost prompt investigations into new, alternative treatment modalities. One such alternative is a long-known anti-inflammatory and chemopreventive component of turmeric spice, curcumin, which was only recently reported to significantly attenuate or ameliorate experimentally induced colitis in mice. Curcumin is poorly absorbed, and extensively metabolized in the gastrointestinal tract, which may account for the reported lack of toxicity. The goal of this proposed project is to investigate the mechanism of curcumin's protective action against colitis in further detail and to provide a sufficient scientific background for clinical trials in both pediatric and adult IBD patients. This will be accomplished by studying the effectiveness of dietary curcumin in immune-based mouse models of colitis. IL-10-/- and TCRalpha-/- mice with different propensities for immune dysregulation (Th1- and Th2-dominated, respectively) will be used. Macroscopic, morphological, and biochemical evaluation will be followed by comparative genome-wide microarray analyses of gene expression profiles in colonic epithelial and immune cells in order to gain further insight into molecular targets of curcumin and its mechanism of action. Also, epithelial metabolism of curcumin will be qualitatively and quantitatively analyzed in colonocytes isolated from control mice and from mice with established differentially polarized inflammation with the help of HPLC/LC-MS technology. The compounds identified as novel metabolites of curcumin will be evaluated for anti-inflammatory activity utilizing established models of mouse macrophages (RAW264.7) and colonocytes (YAMC cells). To shed more light into novel mechanisms of curcumin action in the intestine, its effects on expression of colonic antibacterial cryptdin -related peptides will be investigated. Also, we will describe its mechanism of action on identified uniquely regulated genes such as LPS-mediated early induction of MIP-2 (murine homologue of IL-8) gene transcription. In summary, the proposed project will provide novel information about the mechanism of curcumin's action in IBD, about its molecular targets in differently polarized T-cell mediated inflammation as well as about the molecular forms of the active compound in the healthy and inflamed colon.