A role for autophagy in β-cell life and death.

Autophagy is a vacuolar, self-digesting mechanism responsible for the removal of organelles and defined regions of the cytoplams. This process has, in general, a beneficial role for the cell, since it regulates the turnover of aged proteins and eliminates damaged structures. However, cells that undergo altered autophagy may be triggered to die in a non-apoptotic manner. As a matter of fact, in recent years it has become clear that dysregulated autophagy may be implicated in several disorders, such as cancer, neurodegenerative diseases and hepatic encephalopathy. We have recently shown that β-cells of type 2 diabetic subjects show signs of autophagy associated death, which may contribute to the overall loss of β-cell mass in type 2 diabetes. In addition, studies with cell lines and rodent models have demonstrated the importance of autophagy in β-cell function and survival. Altogether, the available evidence supports the view that autophagy is implicated in β-cell pathophysiology, and suggests that addressing the molecular mechanisms involved in autophagic regulation might provide clues  for preventing or treating β-cell damage in diabetes.