Histone deacetylase inhibitors and their potential role in inflammatory bowel diseases.

IBDs (inflammatory bowel diseases) are lifelong manifestations that significantly impair the quality of life of those who suffer from them. Although many therapies are now available, including immunomodulatory drugs such as Infliximab which have efficacy in IBD, not all patients respond and some patients generate autoantibodies against these drugs. Hence the search for novel treatments is ongoing. HDACs (histone deacetylases) are responsible for condensation of chromatin in the nucleus of cells and inhibition of gene transcription and are often dysregulated during cancer. HDAC inhibitors allow normal gene transcription to be restored and provide attractive therapeutic options, as they have been shown to be anti-inflammatory and anti-proliferative in cancer. Indeed, two HDAC inhibitors have been recently approved for the treatment of cutaneous T-cell lymphoma in the U.S.A. Recent research using animal models has shown that HDAC inhibitors may have a beneficial effect in colitis by boosting levels of Foxp3+ (forkhead box P3+) T-regulatory cells that dampen inflammation. In the present paper, we outline the background to IBD, HDACs and their inhibitors as well as discussing their current use in models of IBD.