Antioxidant effects of antioxidant biofactor on reactive oxygen species in human gingival fibroblasts

The purpose of this study was to investigate the effects of antioxidant biofactor (AOB) on reactive oxygen species (ROS). Generation of superoxide radical (O-2(center dot-)) and hydroxyl radical ((OH)-O-center dot) was determined using an electron spin resonance (ESR) spin-trapping method. AOB was added at different concentrations to these free radical generating systems. The generation of both O-2(center dot-) and (OH)-O-center dot was scavenged by the addition of AOB in a dose-dependent manner. These results indicate that AOB has strong antioxidant properties against these radicals. We further investigated the anti-oxidative effect of AOB on human gingival fibroblasts (HGFs). HGFs were treated for 3 h with alpha-MEM containing a combination of AOB and H2O2 (AOB + H2O2 group), containing H2O2 (H2O2 group), or containing AOB alone (AOB group). Non-stimulated HGFs were used as a control group. The number of surviving cells was in the order of the AOB group > control group > AOB + H(2)o(2) group > H2O2 group. The level of expression of type I collagen mRNA and production of collagen were also in the order of the AOB group > control group > AOB + H2O2 group > H2O2 group. In conclusion, our results suggest that AOB may protect HGFs against oxidative stress by reducing stress-induced ROS.