FRRC Highlight: This note Highlights a Seminal Paper Published in Free Rad. Res. Comms. 1, 163–172 (1986): The Development of a Sensitive Analysis for 8-Hydroxy-2′-Deoxyguanosine

Abstract

We were fortunate to be able to first show that 8-hydroxy-2'-deoxyguanosine (8OHdG) could be sensitively quantitated (to 20 femto moles) by the use of HPLC with electrochemical detection.' This method provides a means to help assess the role of activated oxygen attack on DNA (and RNA) and as such provides data to understand oxidative stress' in biological systems. Tiger in Blake's poem by that title could refer to sagacity, defiance and doubt, but it is equally clear that serendipity, dependence upon the creative and rigorous observations of other researchers and determination fueled by curiosity and dissatisfaction must play an equally important role in exploring new areas and approaches scientifically. Perhaps all three aspects were operating to help make our first observations possible. It is important to acknowledge the following set of circumstances which significantly contributed: (a) Dr. S. Nishimura's generosity in providing us with an authentic standard of 8-OHdG, (b) Dr. P. Wong's collaborative expertise whose training in HPLC-electrochemical detection (HPLC-ED) derives from the pioneering efforts on this analytical technique in biological systems by Drs. L. Blank and R. Adams, (c) our first efforts to use HPLC-ED to detect reduced spin-adducts' and hydroxyl free radical reaction products of phenol and salicylate4 and (d) a persistent fascination with the fundamental chemistry of the toxic aspects of oxygen on biological systems and especially oxygen free radical reactions with nucleic acids.' Since the earlier observations, 8-OHdG has been demonstrated to be formed in the DNA of several biological systems undergoing oxidative stress. Nishimura's group has found, using a wide range of systems, a positive correlation between 8-OHdG formation in DNA and conditions enhancing cancer We have demonstrated that certain chromium salts and betel nut quid, agents responsible for cancer development, cause formation of 8-OHdG in Of significance is the fact that Kuchino et al. demonstrated that 8-OHdG in the DNA template caused miscoding not only of the complementary base but bases on either side of 8-OHdG. It has also been demonstrated that the 8-OHdG content of mitochondria1 DNA is higher than that of nuclear Along this same line, we have noted that the 8-OHdG content of plant chloroplast DNA is higher than nuclear DNA, and that ozone injured plants have a higher content of 8-OHdG in their chloroplast DNA.