Review ArticleMicro-RNAs as regulators and possible diagnostic bio-markers in inflammatory bowel disease

Not fully defined pathophysiologic mechanisms of inflammatory bowel disease (IBD) involve an array of genetic, epigenetic, infectious, physiological and immunological factors. Nowadays, an inadequate activation of the innate immune system to a luminal factor occurring in genetically predisposed subjects is the most widely accepted today. Micro-autoimmune diseases, a group of small, single-stranded, non-coding RNA molecules act as potent negative gene regulators. Beyond cancer and various autoimmune diseases, their impact on IBD has recently been the focus of research. Differential expression of various micro-RNAs has been documented in active and inactive ulcerative colitis, while micro-RNA profile appears to differ between ileal and colonic Crohn's disease. Except for tissue samples, attempts have been made to estimate similar differences at patients' blood samples. Apart from offering new directions in related research, these molecules arise as useful diagnostic tools and potential therapeutic targets. This review focuses on micro-RNA alterations in IBD and their potential implication on immunologic deregulation.

Research highlights► MiRNAs have emerged as a new class of modulators of gene expression at prost-transcriptional level and seems to play a crucial role in various biological processes. ► MiRNAs are implicated in the function of immune cells, which suggest that are implicated in the development of inflammatory conditions such as inflammatory bowel disease. ► The differential expression of miRNAs and their role in inflammatory bowel disease has been few investigated.