Effects of caloric restriction on SIRT1 expression and apoptosis of islet beta cells in type 2 diabetic rats
Authors:
- 30 October 2009
- journal article
- Published by Springer Nature in Acta Diabetologica
- Vol. 47 (1) , 177-185
Abstract
Increasing evidence suggests that a restricted caloric intake extends the life span of mammals, and SIRT1 may play a key role in this process. To study the effects of caloric restriction on SIRT1 expression and apoptosis of islet beta cells in type 2 diabetic rats, we first induced a model of type 2 diabetes in rats with a low-dose of streptozotocin. Then, the rats were fed with a normal diet, high-fat diet or 60% caloric restriction, respectively. As a result, the apoptosis ratio of islet beta cells in diabetic rats was dramatically increased compared to the control group, and mRNA and protein expression of SIRT1 in islet beta cells were much lower than those of the control group. After caloric restriction for 1 month, the blood glucose and serum insulin of rats decreased. The mRNA and protein expression of SIRT1 in islet beta cells significantly increased; however, the apoptosis ratio of islet beta cells decreased remarkably. These data show that caloric restriction notably improves the sensitivity to insulin and significantly increases mRNA and protein expression of SIRT1 while decreasing the apoptosis ratio of islet beta cells in diabetic rats. Therefore, SIRT1 may play an important role in the apoptosis of islet beta cells of type 2 diabetes.Keywords
This publication has 32 references indexed in Scilit:
- The number of podocyte and slit diaphragm is decreased in experimental diabetic nephropathyActa Cirurgica Brasileira, 2006
- Sirt1: a metabolic master switch that modulates lifespanNature Medicine, 2006
- Sirt1 Regulates Insulin Secretion by Repressing UCP2 in Pancreatic β CellsPLOS Biology, 2005
- Increased dosage of mammalian Sir2 in pancreatic β cells enhances glucose-stimulated insulin secretion in miceCell Metabolism, 2005
- Calorie Restriction— the SIR2 ConnectionCell, 2005
- Type 2 Diabetes-a Matter of ß-Cell Life and Death?Science, 2005
- Prevention of core cell damage in isolated islets of Langerhans by low temperature preconditioningWorld Journal of Gastroenterology, 2005
- The effects of dietary caloric restriction on antioxidant status and lipid peroxidation in mild and severe streptozotocin-induced diabetic ratsClinica Chimica Acta, 2004
- Antioxidant enzyme activity and mRNA expression in the islets of Langerhans from the BB/S rat model of type 1 diabetes and an insulin-producing cell lineJournal of Molecular Medicine, 2004
- Decreased beta-cell mass in diabetes: significance, mechanisms and therapeutic implicationsDiabetologia, 2004