Objective: To explore the change of a cell mass and its mechanism with diabetic progress.
Methods: Diabetic mice were killed by exsanguinations after 4, 12 and 20 weeks of diabetes, respectively. Indirect double immunofluorescences for Insulin/Ki67, or BrdU, Cleaved-Caspase 3, TUNEL were used to evaluate pancreatic alpha cell mass, regeneration and apoptosis of a cells. Indirect triple immunofluorescences for Glucagon/ Neurogenin 3/MafA and Western blot analysis for Neurogenin 3 were used to determine neogenesis of pancreatic alpha cells.
Results: Pancreatic alpha cell mass was gradually increased with diabetic progress. It was significantly different from that of controls. There weren't any proliferation and apoptosis of alpha cell during diabetes, however, many Neurogenin 3+ cells appeared in the pancreatic islets of diabetic mice, and most of them were co-stained with MafA and Glucagon.
Conclusion: Pancreatic alpha cell mass is gradually increased with diabetic progress. It seems to be strongly associated with neogenesis of pancreatic alpha cells.