The effect of antioxidants on oxidative DNA damage induced by visible-light-irradiated camphorquinone/N,N-dimethyl-p-toluidine

Biomaterials. 2005 Sep;26(26):5321-9. doi: 10.1016/j.biomaterials.2005.01.068.


Previous investigations have found that visible-light (VL)-irradiated camphorquinone (CQ), in the presence of a tertiary amine (e.g., N,N-dimethyl-p-toluidine, DMT), generates reactive oxygen species and causes oxidative DNA damage in vitro. In this study, oxidative DNA damage produced by VL-irradiated CQ/DMT, in the presence and absence of antioxidants (glutathione, N-acetyl-L-cysteine (NAC), mannitol, vitamin C, and vitamin E), was measured by the conversion of PhiX-174 RF I supercoiled (SC) double-stranded plasmid DNA into open and linear forms. VL-irradiated CQ/DMT, lacking antioxidant, damaged 99.4 +/- 1% of the PhiX-174 RF I SC double-stranded plasmid DNA. Our results revealed that glutathione (10.0, 5.0, 2.5, 1.0, and 0.5 mm) and NAC (10.0, 5.0, and 2.5 mm) significantly (p < 0.02) reduced oxidative DNA damage produced by VL-irradiated CQ/DMT. Vitamin E, vitamin C, and mannitol were ineffective at reducing oxidative DNA damage produced by VL-irradiated CQ/DMT. Furthermore, vitamin E (10.0 and 5.0 mm) and vitamin C (10.0, 5.0, 2.5, 1.0, 0.5 mm) treatment significantly (p < 0.02) enhanced VL-irradiated CQ/DMT-induced oxidative DNA damage and caused significant (p < 0.001) DNA damage following VL-irradiation in the absence of CQ/DMT. As a result, future studies should evaluate whether glutathione and NAC effectively reduce or prevent oxidative damage induced by VL-irradiated CQ/DMT in vivo.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antioxidants / chemistry*
  • Body Fluids / chemistry
  • Bone Cements / chemistry
  • Bone Cements / radiation effects
  • DNA / analysis
  • DNA / chemistry*
  • DNA Damage*
  • Humans
  • Light
  • Materials Testing
  • Oxidation-Reduction
  • Reactive Oxygen Species / chemistry
  • Terpenes / chemistry*
  • Terpenes / radiation effects*
  • Toluidines / chemistry*
  • Toluidines / radiation effects*


  • Antioxidants
  • Bone Cements
  • Reactive Oxygen Species
  • Terpenes
  • Toluidines
  • camphoroquinone
  • DNA
  • dimethyl-4-toluidine