miRNA在炎症性肠病发病过程中的作用

Role of miRNAs in pathogenesis of inflammatory bowel disease

微小RNA(microRNA,miR)是一类非编码的内源性小分子RNA,能在转录后水平负性调节靶mRNA表达.炎症性肠病(inflammatory bowel disease,IBD)的发病机制与免疫异常、炎症损伤、遗传等因素密切相关.miRNA在肠道的差异性表达是调控肠黏膜屏障功能的重要环节,影响肠道上皮细胞的增殖、分化以及肠道黏膜的免疫功能,与IBD的发生发展密切相关.目前已发现多种miRNA在IBD患者在血清和肠黏膜组织异常表达,活动性溃疡性结肠炎较正常肠黏膜表达明显下调如miR-192、miR-375、miR-422b,而miR-16、miR-21、let-7等表达明显上调;活动性克罗恩病较正常肠黏膜表达明显下调如miR-19b、miR-629,miR-23b、miR-106和miR-191的表达明显上调.这为IBD的早期诊断、预防和治疗提供了分子靶标.

MicroRNA （miRNA） is a kind of endogenous small-molecule RNAs that can direct mRNA degradation and translational inhibition post- transcriptionally by binding to complementary sequences in the 3＇untranslated regions of specific target mRNAs. The pathogenesis of inflammatory bowel disease （IBD） is associated with immune response, inflammatory injury, and genetic fac- tors. MiRNAs play multiple important roles in the intestinal epithelium, influencing a number of intestinal disease processes. This review summa- rizes the regulatory role of miRNAs in intestinal epithelial differentiation, architecture, membrane permeability, immunological function, and more importantly, intestinal mucosal barrier dysfunc- tion in IBD. It has been found that many miRNAs in the serum and intestinal mucosa of IBD patients show abnormal expression. In active UC miR-192, miR-375 and miR422b were significantly down-regulated, and miR-16, miR-21 and let-7 up-reg- ulated compared with normal intestinal mucosa. In active CD miR-19b and rniR-629 were signifi- cantly down-regulated, and miR-23b, miR-106 and miR-191 were up-regulated. MicroRNAs provide molecular targets for prevention, early diagnosis and treatment of IBD.