Table 1.
Endogenous, Exogenous, and Sum of N2-Ethylidene-dG Levels from [13C2]-Acetaldehyde Exposures in TK6 Cells
| [13C2]-Acetaldehyde (µM) | Endogenous adducts/107 dG (mean ± SD) | Exogenous adducts/107 dG (mean ± SD) | Sum adducts/107 dG (mean ± SD) | Exogenous versus endogenous, p value | Sum versus mean, p value | n |
|---|---|---|---|---|---|---|
| 0 | 2.0±0.65 | N.D. | 2.0±0.65 | — | — | 5 |
| 0.05 | 2.7±1.1 | N.D. | 2.7±1.1 | — | — | 6 |
| 0.1 | 2.4±0.84 | 0.2±0.06* | 2.5±0.85 | — | — | 6 |
| 1 | 2.7±1.0 | 0.05±0.02 | 2.7±1.0 | 1.52E−03 | 7.06E−01 | 6 |
| 5 | 3.0±1.0 | 0.38±0.17 | 3.3±1.0 | 1.19E−03 | 2.20E−01 | 6 |
| 10 | 3.4±0.96 | 0.93±0.42 | 4.2±1.3 | 8.71E−04 | 2.78E−02 | 6 |
| 50 | 3.0±0.79 | 5.0±1.8 | 8.0±2.4 | 6.22E−02 | 4.96E−03 | 5 |
| 250 | 2.8±0.81 | 32±11 | 34±12 | 1.44E−03 | 6.16E−04 | 6 |
| 500 | 2.9±1.1 | 78±22 | 81±22 | 3.94E−04 | 1.82E−04 | 6 |
| 1000 | 4.2±1.6 | 180±62 | 180±61 | 1.05E−03 | 4.33E−04 | 6 |
| 2000 | 4.1±3.0 | 390±120 | 400±120 | 4.84E−04 | 2.25E−04 | 6 |
Notes. The endogenous mean across all exposure concentrations and the control was 3.0±1.4 adducts/107 dG. The sum was calculated by adding the endogenous and exogenous adducts from each sample, and mean and SD were calculated. A statistical comparison of exogenous and endogenous adducts was conducted using a t-test with a Bonferroni multiple-testing threshold for an overall false-positive rate of 0.05, corresponding to 0.005 as the threshold for each test. A second comparison between the sum of adducts and the endogenous mean was conducted using the same Bonferroni correction. *For the 0.1µM concentration, two samples had quantifiable amounts of exogenous adducts (shown). The remaining four samples did not have detectable levels of the exogenous adducts.