Suppression of SOCS3 expression in the pancreatic β-cell leads to resistance to type 1 diabetes

Type 1 diabetes results from the selective destruction of insulin-producing pancreatic β-cells during islet inflammation, which involves inflammatory cytokines and free radicals. However, mechanisms for protecting β-cells from destruction have not been clarified. In this study, we define the role of SOCS3 on β-cell destruction using β-cell-specific SOCS3-conditional knockout (cKO) mice. The β-cell-specific SOCS3-deficient mice were resistant to the development of diabetes caused by streptozotocin (STZ), a genotoxic methylating agent, which has been used to trigger β-cell destruction. The islets from cKO mice demonstrated hyperactivation of STAT3 and higher induction of Bcl-xL than did islets from WT mice, and SOCS3-deficient β-cells were more resistant to apoptosis induced by STZ in vitro than were WT β-cells. These results suggest that enhanced STAT3 signaling protects β-cells from destruction induced by a genotoxic stress and that STAT3/SOCS3 can be a potential therapeutic target for the treatment of type 1 diabetes.