*2.2. Effect of Resveratrol and CrO3 on 8-OHdG Adduct Levels*

The 8-OHdG adduct was measured at 48 h in blood plasma since this method does not require sacrificing the animals. It is generally accepted that the excretion of the oxidized nucleosides 8-oxodG and 8-oxoGuo can be measured in fluids such as plasma, under the assumption that an organism maintains a steady-state with no changes in the rate of oxidation [25]. In that situation, the number of oxidized guanine moieties in the nucleic acid and its precursor pool must be equal to the number removed/excreted from the cell. Thus, the levels of 8-OHdG evaluated in fluids represent the balance between formation and repair rates. When evaluating oxidative damage to DNA using the 8-OHdG adduct repair levels in peripheral blood plasma analyzed by one-way ANOVA, there was a significant effect of treatment (*p* < 0.0015). The group treated with resveratrol prior to CrO3 (resveratrol + CrO3) had higher 8-OHdG levels than the control groups (C1, *p* < 0.012; C2, *p* < 0.007) and the CrO3 group (*p* < 0.002) (Figure 2). Although the resveratrol group displayed numerically higher 8-OHdG levels than the control C2 and CrO3 had lower levels than control C1, neither comparison was statistically significant.

**Figure 2.** Effect of resveratrol and CrO3 on 8-hydroxydeoxyguanosine (8-OHdG, 7,8-dihydro-8-oxodeoxyguanosine) levels evaluated in peripheral blood plasma 48 h after treatments (*n* = 4 mice/group). Statistical significance was determined using one-way ANOVA followed by Tukey's post-hoc test: <sup>a</sup> *p* < 0.012 vs. C1; <sup>b</sup> *p* < 0.007 vs. C2; <sup>c</sup> *p* < 0.002 vs. CrO3. C1, Control 1, vehicle only (distilled water); C2, Control 2, vehicle only (ethanol 30%); CrO3, chromium trioxide.
