Elevated cAMP level attenuates 2-deoxy-d-ribose-induced oxidative damage in pancreatic beta-cells

Arch Biochem Biophys. 2005 Jun 1;438(1):70-9. doi: 10.1016/j.abb.2005.03.018. Epub 2005 Apr 9.

Abstract

Glucose toxicity to pancreatic beta-cells is defined as irreversible beta-cell damage, including apoptosis, caused by chronic exposure to high glucose levels in type 2 diabetes. Oxidative stress is an important mechanism for glucose toxicity to pancreatic beta-cells. Reducing sugars produce reactive oxygen species through autoxidation and protein glycosylation. 2-Deoxy-d-ribose (dRib) is a reducing sugar with high reactivity. We investigated whether cAMP-stimulating agents could protect beta-cells from dRib-induced oxidative damage. HIT-T15 cells were cultured with various concentrations of dRib for 24 h. We measured cell survival, intracellular cAMP and H2O2 levels, and apoptosis. dRib decreased cell survival in a dose- and time-dependent manner and markedly increased intracellular H2O2 levels and apoptosis. N-Acetyl-l-cysteine decreased dRib-induced rises in intracellular H2O2 and apoptosis to control levels. Forskolin, IBMX, and dbcAMP markedly elevated intracellular cAMP levels and significantly attenuated dRib-induced cytotoxicity and apoptosis, but had no influence on the dRib-induced rise in intracellular H2O2 levels. These results demonstrate that dRib produced oxidative stress and apoptosis in pancreatic beta-cells and that elevated intracellular cAMP levels reduced dRib-induced damage, independent of reactive oxygen species metabolism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis / physiology
  • Cell Line
  • Cell Survival / drug effects
  • Cricetinae
  • Cyclic AMP / metabolism*
  • Deoxyribose / pharmacology*
  • Dose-Response Relationship, Drug
  • Drug Resistance / physiology
  • Islets of Langerhans / drug effects*
  • Islets of Langerhans / metabolism*
  • Oxidation-Reduction / drug effects
  • Oxidative Stress / drug effects*
  • Oxidative Stress / physiology*

Substances

  • Deoxyribose
  • Cyclic AMP