Table 2.
Primary DNA damage in HT-29 and RKO cells exposed for 4 h to different concentrations of ALEs. Extent of DNA strand breakage is expressed in terms of tail intensity (% DNA migrated in the comet tail); results of each experimental set are summarized as the mean value of three independent experiments (±SEM).
| HT-29 | RKO | |||
|---|---|---|---|---|
| ALEs | Tail Intensity (% DNA) |
Hedgehog Cells(%) |
Tail Intensity (% DNA) |
Hedgehog Cells (%) |
| Extract A 1 | ||||
| 1 mg/mL | 45.65 ± 6.37 * | 16.67 ± 2.40 | 50.45 ± 10.17 * | 10.5 ± 3.5 |
| 2 mg/mL | 85.23 ± 1.88 * | 80.00 ± 4.62 * | 84.39 ± 3.05 * | 51.0 ± 2.0 * |
| 4 mg/mL | 84.03 ± 2.47 * | 69.33 ± 16.71 * | 83.38 ± 1.06 * | 47.0 ± 3.0 * |
| Extract B 1 | ||||
| 5 µg/mL | 0.93 ± 0.11 | 0.00 ± 0.00 | ||
| 10 µg/mL | 1.48 ± 0.44 | 0.67 ± 0.67 | ||
| 20 µg/mL | 1.54 ± 0.36 | 0.00 ± 0.00 | ||
| Extract C 1 | ||||
| 5 µg/mL | 1.98 ± 0.27 | 0.00 ± 0.00 | ||
| 10 µg/mL | 1.55 ± 0.41 | 1.33 ± 0.67 | ||
| 20 µg/mL | 0.73 ± 0.10 | 0.00 ± 0.00 | ||
| Extract D 1 | ||||
| 0.5 mg/mL | 86.50 ± 4.50 * | 74.00 ± 21.01 * | 90.19 ± 2.34 * | 66.0 ± 3.0 * |
| 1 mg/mL | 90.16 ± 1.65 * | 78.00 ± 8.00 * | 87.28 ± 0.52 * | 60.0 ± 4.0 * |
| 2 mg/mL | 85.51 ± 6.50 * | 57.33 ± 25.98 | 68.93 ± 7.85 * | 20.5 ± 6.5 |
| Controls: | ||||
| DMEM 2 | 0.38 ± 0.16 | 0.00 ± 0.00 | 1.11 ± 0.57 | 0.00 ± 0.00 |
| DMSO 3 | 0.86 ± 0.43 | 0.00 ± 0.00 | ||
| 4NQO 4 | 14.52 ± 3.58 | 0.67 ± 0.67 | 37.80 ± 2.14 | 0.00 ± 0.00 |
1 Primary DNA damage was determined using the three highest concentrations which did not show cytotoxic effects in the lactate dehydrogenase (LDH) leakage test, starting by the top concentration (see Table 1). 2,3 Negative control for Samples A, D, and B, C, respectively. 4 Positive control. Statistical analysis: * indicates significantly higher levels of primary DNA damage or number of hedgehog cells, as compared with negative control (p < 0.05), one-way ANOVA followed by Dunnett’s post hoc analysis.