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Oxidative Medicine and Cellular Longevity
Volume 2012, Article ID 390678, 7 pages
http://dx.doi.org/10.1155/2012/390678
Research Article

Gliclazide Does Not Fully Prevent 2-Deoxy-D-Ribose-Induced Oxidative Damage Because It Does Not Restore Glutathione Content in a Pancreatic β-Cell Line

Department of Internal Medicine, Jeju National University School of Medicine, 66 Jejudaehakno, Jeju 690-756, Republic of Korea

Received 30 August 2011; Revised 14 October 2011; Accepted 20 October 2011

Academic Editor: Neelam Khaper

Copyright © 2012 Gwanpyo Koh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We compared the effects of gliclazide, an antidiabetic agent with antioxidant properties, and N-acetyl-L-cysteine (NAC), a glutathione precursor, in protecting against 2-deoxy-D-ribose- (dRib-) induced oxidative damage in HIT-T15 cells. Using trypan blue staining and flow cytometry with annexin V/PI staining, gliclazide treatment slightly reversed dRib-induced cell death and apoptosis, and NAC treatment markedly reduced both measures. Likewise, flow cytometry using DHR 123 staining showed that the levels of dRib-induced reactive oxygen species (ROS) were partially suppressed by gliclazide and completely inhibited by NAC. Using electron spin resonance spectrometry, gliclazide and NAC scavenged hydroxyl radicals generated by Fenton reaction to a similar degree in a cell-free system. NAC, but not gliclazide, completely restored the intracellular glutathione depleted by dRib using monochlorobimane fluorescence and glutathione assays. Thus, gliclazide treatment suppressed dRib-induced oxidative damage in HIT-T15 cells less than NAC did because gliclazide did not restore the intracellular glutathione content as effectively as NAC. In addition, the elevation of intracellular glutathione rather than free radical scavenging might be an important mechanism for protecting against dRib-induced oxidative damage in a β-cell line.