Type 1 diabetes is caused by autoimmune β cell destruction and therefore regeneration of these cells could help reverse the disease. But the molecules required to initiate and continue this process remain to be identified. In 1 May Journal of Clinical Medicine, Mónica George and colleagues from Universitat Autònoma de Barcelona, Bellaterra, Spain show that that local expression of IGF-I in β cells regenerates pancreatic islets and leads to recovery from type 1 diabetes.

George et al. observed that expression of IGF-I in β cells of transgenic mice (in both C57BL/6–SJL and CD-1 genetic backgrounds) counteracts cytotoxicity and insulitis induced by multiple low doses of streptozotocin (STZ). While all normal control STZ treated mice developed diabetes and died, STZ-treated CD-1 transgenic mice gradually normalized all metabolic parameters and survived. In addition, β cell mass of the transgenic mice increased in parallel as a result of neogenesis and...