期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：47
页码：E7545-E7553
DOI：10.1073/pnas.1616447113
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceInflammatory bowel disease (IBD) is a debilitating disorder with limited treatment options. Here, we report that manipulation of Hedgehog (Hh) pathway signaling affects disease severity in the well-established dextran sulfate mouse model of colitis. Genetic and pharmacologic manipulations that decrease Hh pathway signaling in the colon worsen colitis. Conversely, manipulations that increase Hh pathway signaling ameliorate colitis. We find that Hh pathway stimulation exerts its effects partially through increased expression of the antiinflammatory cytokine IL-10 in Hh pathway-responsive stromal cells and concomitant increases in CD4+Foxp3+ regulatory T cells in the colon. Our studies suggest that pharmacologic Hh pathway stimulation in colonic stromal cells may be a strategy to treat IBD. Inflammation disrupts tissue architecture and function, thereby contributing to the pathogenesis of diverse diseases; the signals that promote or restrict tissue inflammation thus represent potential targets for therapeutic intervention. Here, we report that genetic or pharmacologic Hedgehog pathway inhibition intensifies colon inflammation (colitis) in mice. Conversely, genetic augmentation of Hedgehog response and systemic small-molecule Hedgehog pathway activation potently ameliorate colitis and restrain initiation and progression of colitis-induced adenocarcinoma. Within the colon, the Hedgehog protein signal does not act directly on the epithelium itself, but on underlying stromal cells to induce expression of IL-10, an immune-modulatory cytokine long known to suppress inflammatory intestinal damage. IL-10 function is required for the full protective effect of small-molecule Hedgehog pathway activation in colitis; this pharmacologic augmentation of Hedgehog pathway activity and stromal IL-10 expression are associated with increased presence of CD4+Foxp3+ regulatory T cells. We thus identify stromal cells as cellular coordinators of colon inflammation and suggest their pharmacologic manipulation as a potential means to treat colitis.
