Anti-inflammatory effect of phenethyl isothiocyanate, an active ingredient of Raphanus sativus Linne

Phenethyl isothiocyanate (PEITC) is an active ingredient of Raphanus sativus Linne (Cruciferae). However, regulatory mechanism of PEITC involved in caspase-1 signalling has not been fully elucidated in mast cells. First, PEITC inhibited the production of IL-6 through the inhibition of caspase-1/receptor-interacting protein 2, followed by regulation of NF-κB/IκBα pathway or p38 and extracellular signal-regulated kinase mitogen-activated protein kinases. Second, PEITC inhibited the IL-1β production through the inhibition of caspase-1 proteolytic activity. Overall, these results provide a proof that PEITC can inhibit the inflammatory reactions by two distinct pathways in mast cells and open new perspectives to pharmacologically manipulate the expression and production of IL-6 and IL-1β by molecules acting on the caspase-1 pathway.