PMID: 11928219Apr 4, 2002Paper

Potential role of the early response gene c-Myc in the loss of differentiation and function of pancreatic beta cells submitted to chronic hyperglycemia

Bulletin et mémoires de l'Académie royale de médecine de Belgique
J C Jonas

Abstract

Chronic hyperglycemia exerts deleterious effects on glucose-induced insulin secretion by pancreatic beta cells. In 90% pancreatectomized rats, chronic hyperglycemia induces beta cell hypertrophy and loss of differentiation associated with increased expression of the early response gene c-Myc. Hyperglycemia also stimulates c-Myc expression in vivo in islets from glucose-infused rats and in vitro in cultured rat islets. This effect requires the elevation of cytosolic Ca2+ concentration produced by glucose. Our results suggest that overstimulation of c-Myc expression by chronic hyperglycemia may be the cause of beta cell hypertrophy and loss of differentiation and function observed in animal models of type 2 diabetes.