Regeneración de las células beta de los islotes pancreáticos. Estudio en ratones nod (non-obese diabetic)

Resumen

Diabetes is a growing global health problem. Insulin-secreting beta-cells can multiply in response to different stimuli like pregnancy, insulin resistance or pancreatectomy. Previous studies on type-1 diabetes (DM1) show that there is a compensatory replication during the process of insulitis, when the beta cell mass becomes critical. In the present work, a number of anatomical (body weight), biochemical (glycemia, insulinemia) and histological (number of islets, insulitis degree, beta-cells area and replication rate) parameters have been studied in a population of NOD and NOD/Scid male mice, which have received less attention than females. The analysis of the temporal evolution of individual and average values, together with their relationship with the degree of insulitis (in NOD mice) indicate that, while some parameters change according to the age of the mice, others do according to the insulitis degree. Therefore, it seems necessary to study both characteristics before drawing conclusions. Interestingly, histological studies showed that there is a replication peak just before the onset of DM1 in the male mice of NOD strain. We also found a common alteration in the pancreas of both the NOD and NOD/Scid strains, pathological islet destruction that courses with a progressive movement of islets to the peripheria of the lobules and the final extrusion of the islets to the extralobular space. To our knowledge this phenomenon has not been previously described. These findings demonstrate that NOD male populations are more heterogeneous than females, both in the development of insulitis and diabetes, and in the evolution of biochemical parameters.