Oxidative stress increases glyceraldehyde-3-phosphate dehydrogenase mRNA levels in isolated rabbit aorta

We have recently shown that inhibition of endogenous Cu,Zn superoxide dismutase (SOD) by diethyldithiocarbamate (DDC) increased superoxide anion levels in isolated rabbit aortic rings, describing a useful experimental model to examine the effects of oxidative stress on the vessel wall. The present study examined the effects of oxidative stress on the steady-state mRNA levels of glyceraldehyde-3-phosphate dehydrogenase (GAPDH; EC 1.2.1.12). Aortic rings were incubated in physiological salt solution at 37 degrees C for up to 6 h. DDC (2 mM) decreased total SOD activity to <5% of control levels and increased superoxide anion level ninefold. Steady-state mRNA levels of GAPDH were increased under comparable conditions. Although decreased biological activity of endothelium-derived nitric oxide was indicated by lower basal guanosine 3',5'-cyclic monophosphate levels in aortic rings treated with DDC compared with those in control rings (1.2 +/- 0.1 vs. 1.9 +/- 0.3 fmol/mu g protein, P < 0.05), neither endothelium denudation nor N-G-nitro-L-arginine methyl ester had any effects on the steady-state mRNA levels of GAPDH. The cell-permeable iron chelator 1,10-phenanthroline completely prevented the increases in GAPDH mRNA levels induced by DDC. These results suggest that oxidative stress resulting from inhibition of endogenous Cu,Zn SOD causes induction of GAPDH gene expression and that the hydroxyl radical, produced through the iron-catalyzed Haber-Weiss reaction, is the intracellular reactive oxygen species responsible for the DDC-stimulated increase in GAPDH mRNA.