Growth arrest- and DNA-damage-inducible 45β gene inhibits c-Jun N-terminal kinase and extracellular signal-regulated kinase and decreases IL-1β-induced apoptosis in insulin-producing INS-1E cells

摘要

IL-1β is a candidate mediator of apoptotic beta cell destruction, a process that leads to type 1 diabetes and progression of type 2 diabetes. IL-1β activates beta cell c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38, all of which are members of the mitogen-activated protein kinase (MAPK) family. Inhibition of JNK prevents IL-1β-mediated beta cell destruction. In mouse embryo fibroblasts and 3DO T cells, overexpression of the gene encoding growth arrest and DNA-damage-inducible 45β (Gadd45b) downregulates pro-apoptotic JNK signalling. The aim of this study was to investigate if Gadd45b prevents IL-1β-induced beta cell MAPK signalling and apoptosis.