Glucose and alpha-ketoisocaproate, the keto acid analogue of leucine, stimulate insulin secretion in the absence of other exogenous fuels. Their mitochondrial metabolism in the beta-cell raises the cytosolic ATP/ADP ratio, thereby providing the triggering signal for the exocytosis of the insulin granules. However, additional amplifying signals are required for the full extent of insulin secretion stimulated by these fuels. Whi...

Apparently, both a decrease in beta cell function and in beta cell mass contribute to the progressive worsening of type 2 diabetes. So, it is of particular interest to define factors which are relevant for the regulation of insulin secretion and at the same time for the maintenance of beta cell mass. The NADPH-thioredoxin system has a candidate role for such a dual function. Here, we have characterized the effects of a highly...