Histone deacetylase inhibitors in inflammatory disease

Lysine acetylation is becoming increasingly appreciated as a key post-translational modification in the endogenous regulation of protein function. The so-called histone acetyl transferases (HATs) and histone deacetylases (HDACs), best known for their roles in controlling chromatin remodeling via histone acetylation/deacetylation, are now known to modify a large number of non-histone proteins to control diverse cell processes. In relation to inflammation, acetylation modulates the activity or function of cytokine receptors, nuclear hormone receptors, intracellular signaling molecules and transcription factors. Small molecule inhibitors of HDACs have been found to trigger both pro- and anti-inflammatory effects in a range of inflammation-relevant cell types. Although their inflammatory profiles have only just begun to be elucidated, some HDAC inhibitors are already showing therapeutic promise in animal models of inflammatory diseases such as arthritis, inflammatory bowel diseases, septic shock, ischemia-reperfusion injury, airways inflammation and asthma, diabetes, age-related macular degeneration, cardiovascular diseases, multiple sclerosis and other CNS and neurodegenerative diseases. This article describes those HDAC inhibitors which have been most examined to date for their potentially beneficial effects on inflammatory cells or in animal models of inflammatory disease.