ascorbic-acid and camphoroquinone

The objective of this investigation was to analyze whether various combinations of the ROS scavengers glutathione (GSH), N-acetyl-cysteine (NAC), and vitamins C and E decrease DNA damage due to visible-light-irradiated (VL-irradiated) camphorquinone/N,N-dimethyl-p-toluidine (CQ/DMT) compared with individual vitamin C or E. PhiX-174 RF plasmid DNA was used to determine single and double strand breaks as parameters of DNA damage. Individual ROS scavengers and combinations of the antioxidants were added to plasmid DNA treated with VL-irradiated CQ/DMT/Cu (II). After incubation, DNA was loaded into a 1% agarose gel. Following electrophoresis, gels stained with 0.5 microg/mL ethidium bromide were photographed under ultraviolet illumination and analyzed with NIH ImageJ software. Results were evaluated between groups for statistical significance using Student's paired t-test (p < 0.05). Glutathione significantly reduced oxidative DNA damage at all test concentrations when combined with vitamin C or vitamin E. The concentration of damaged DNA observed in the presence of combinations of GSH with vitamin C or vitamin E was significantly lower compared with all other combinations of antioxidants investigated in our study (p < 0.05). In contrast to GSH, NAC was not able to compensate the pro-oxidative effects of vitamin C and vitamin E. Only at a concentration of 2 mM, NAC combined with vitamin C efficiently prevented CQ/DMT/Cu (II)-associated DNA damage. Our data indicate that solely the combinations of GSH with vitamin C or vitamin E significantly reduce the severity of oxidative DNA damage caused by CQ/DMT, whereas NAC may even increase the pro-oxidant activity of vitamin C and vitamin E.

Topics: Acetylcysteine; Ascorbic Acid; DNA; DNA Damage; Free Radical Scavengers; Glutathione; Light; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species; Terpenes; Toluidines; Vitamin E

Recent studies have revealed that visible-light (VL)-irradiated camphorquinone (CQ), in the presence of a tertiary amine (e.g., N,N-dimethyl-p-toluidine, DMT), generates initiating radicals that may indiscriminately react with molecular oxygen forming reactive oxygen species (ROS). In this study, the ability of the antioxidants N-acetyl-l-cysteine (NAC) and ascorbic acid (AA) to reduce intracellular oxidative stress induced by VL-irradiated CQ/DMT or VL-irradiated hydrogen peroxide (H(2)O(2)) was assessed in an immortalized Murine cementoblast cell line (OCCM.30) and an immortalized Murine fibroblast cell line, 3T3-Swiss albino (3T3). Intracellular oxidative stress was measured with the membrane permeable dye, 2',7'-dichlorodihydrofluorescein diacetate (H(2)DCF-DA). VL-irradiated CQ/DMT and VL-irradiated H(2)O(2) each produced significantly (p<0.001) elevated intracellular oxidative levels in both cell types compared to intracellular ROS levels in VL-irradiated untreated cells. OCCM.30 cementoblasts were found to be almost twice as sensitive to VL-irradiated CQ/DMT and VL-irradiated H(2)O(2) treatment compared to 3T3 fibroblasts. Furthermore, 10mm NAC and 10mm AA each eliminated oxidative stress induced by VL-irradiated CQ/DMT and VL-irradiated H(2)O(2) in both cell types. Our results suggest that NAC and AA may effectively reduce or eliminate oxidative stress in cells exposed to VL-irradiated CQ/DMT following polymerization.

Topics: 3T3 Cells; Acetylcysteine; Animals; Ascorbic Acid; Cell Line; Composite Resins; Dental Cementum; Dental Materials; Drug Interactions; Light; Mice; Oxidative Stress; Reactive Oxygen Species; Terpenes