We know that Retinoic acid is the oxidized form of Vitamin A. It functions in determining position along embryonic anterior/posterior axis in chordates. It acts through Hox genes, which ultimately control anterior/posterior patterning in early developmental stages. Retinoic acid acts by binding to heterodimers of the retinoic acid receptor (RAR) and the retinoid X receptor (RXR), which then bind to retinoic acid response elements (RAREs) in the regulatory regions of direct targets (including Hox genes), thereby activating gene transcription.
Recently when I was reading a paper, found this interesting fact that is "retinoic acid, could be a beneficial treatment for people suffering from ulcerative colitis and other irritable bowel diseases. Specifically the researchers found that retinoic acid helps suppress out-of-control inflammation, which is a hallmark of active ulcerative colitis.
Pharmaceutical strategies based on this research may offer a promising alternative to the current approaches of managing immune diseases including, IBD, arthritis, multiple sclerosis, and so on, Aiping Bai, a researcher involved in the work from Nanchang University in Nanchang City, China claimed.
The studies ultimately found that treatment with retinoic acid reduced the inflammation in the colon by increasing the expression of FOXP3, a gene involved with immune system responses, as well as decreasing the expression of IL-17, a cytokine believed to cause inflammation. Because many experts believe that IL-17 directly relates to the uncontrolled inflammation seen in ulcerative colitis and irritable bowel disease, the discovery that retinoic acid reduces IL-17's ability to cause inflammation could accelerate the development of treatments for these chronic diseases.
Ref : http://www.jleukbio.org/cgi/content/abstract/86/4/959?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=Aiping+Bai&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT