Beta cell nuclear musculoaponeurotic fibrosarcoma oncogene family A (MafA) is deficient in type 2 diabetes.

The beta cell transcriptional factor musculoaponeurotic fibrosarcoma oncogene family A (MafA) regulates genes important for beta cell function. Loss of nuclear MafA has been implicated in beta cell dysfunction in animal models of type 2 diabetes. We sought to establish if nuclear MafA is less abundant in beta cell nuclei in humans with type 2 diabetes. Pancreas obtained at surgery from five non-diabetic individuals and six individuals with type 2 diabetes was immunostained for insulin, glucagon and MafA. Beta cell nuclear MafA was markedly decreased in type 2 diabetes (1.6 ± 1.2% vs 46.3 ± 8.3%, p < 0.001). Beta cell nuclear MafA is markedly decreased in humans with type 2 diabetes, which may contribute to impaired beta cell dysfunction.