Role of MCH in Adipose Tissue & Intestinal Inflammation

描述(申请人提供)：黑色素浓缩激素(MCH)，一种调节食欲和体重的下丘脑神经肽，也被证明在各种原因的结肠炎中起到促炎作用。因此，人肠系膜前脂肪细胞表达MCH受体，而MCH与这些受体结合可刺激IL-8的表达，IL-8是参与IBD发病的中性粒细胞趋化因子。由于克罗恩病患者肠系膜脂肪包裹与促炎细胞因子的表达增加有关，因此MCH可能参与了这种炎症反应。这项研究的目的有两个：1)验证MCH在结肠炎过程中将粘膜炎症与肠系膜脂肪库的炎性变化联系起来的假说；2)核因子-kB和MAP激酶通路在相关信号中的作用。这将通过比较小鼠脂肪库中MCH和MCH受体在蛋白质和mRNA水平的表达与TNBS-、DSS-和IL-10 KO结肠炎的黏膜炎症程度，通过激光捕获显微解剖、免疫组织化学分析和共聚焦显微镜鉴定这些组织中表达MCH/MCHR1的细胞，并通过蛋白质印迹、RT-PCR和ELISA法剖析信号通路。

DESCRIPTION (provided by applicant): Melanin-concentrating hormone (MCH), a hypothalamic neuropeptide that regulates appetite and body weight, has also been shown to play a proinflammatory role in colitis of various etiologies. Thus, mesenteric human preadipocytes express MCH receptors, and MCH binding to these receptors stimulates expression of IL-8, a neutrophil chemoattractant involved in IBD pathogenesis. Since patients with Crohn's disease have mesenteric fat wrapping of the bowel associated with increased expression of proinflammatory cytokines, it is likely that MCH participates in this inflammatory response. The goals of this study are two-fold: 1) To examine the hypothesis that MCH links mucosal inflammation with inflammatory changes in the mesenteric fat depots during colitis and 2) that NF-kB and MAP kinase pathways contribute to the signaling involved. This will be done by comparing MCH and MCH-receptor expression at the protein and mRNA levels in murine fat depots to degree of mucosal inflammation during TNBS-, DSS-, and IL-10 KO colitis, identifying the cells expressing MCH/MCHR1 in this tissue through laser capture microdissection, immunohistochemical analysis, and confocal microscopy and dissecting signalling pathways by western blot, RT-PCR and ELISA.