Table 2.
Cytostasis and cytotoxicity evaluated by CBMN Cyt assay
| CBPI
|
Mitotic index
|
Apoptotic index
|
Necrotic index
|
|||||
|---|---|---|---|---|---|---|---|---|
| PBL | Raw264.7 | PBL | Raw264.7 | PBL | Raw264.7 | PBL | Raw264.7 | |
| C− | 1.88±0.02 | 1.85±0.04 | 6.5±0.1 | 5.6±0.2 | 0.7±0.1 | 1.7±0.2 | 0.2±0.2 | 0.9±0.3 |
| C+ | 1.17±0.13*** | 1.41±0.06*** | 0.3±0.2*** | 2.3±0.6*** | 4.7±0.3*** | 4.6±0.5*** | 2.5±0.4*** | 4.0±0.4 |
| Au NP 5 nm | ||||||||
| 0.1 μg/mL | 1.55±0.02*** | 1.62±0.06** | 3.9±0.2*** | 4.0±0.4*** | 1.2±0.2* | 2.0±0.5 | 1.6±0.3*** | 3.4±0.4*** |
| 1 μg/mL | 1.54±0.05*** | 1.62±0.05** | 4.6±0.6** | 3.9±0.4*** | 1.9±0.5** | 1.2±0.3 | 2.4±0.3*** | 2.1±0.5** |
| 10 μg/mL | 1.47±0.02*** | 1.57±0.05** | 4.4±0.3*** | 3.6±0.3*** | 1.6±0.2** | 1.8±0.5 | 2.6±0.2*** | 2.9±0.2*** |
| 100 μg/mL | 1.36±0.05*** | 1.51±0.07*** | 2.8±0.4*** | 3.1±0.4*** | 1.8±0.4** | 2.6±0.2*** | 3.0±0.6*** | 4.3±0.6*** |
| Au NP 15 nm | ||||||||
| 0.1 μg/mL | 1.70±0.03* | 1.68±0.04** | 4.9±0.5** | 3.7±0.3*** | 1.5±0.1** | 1.7±0.1 | 0.6±0.2* | 1.4±0.2* |
| 1 μg/mL | 1.57±0.02*** | 1.61±0.01*** | 4.0±0.6*** | 2.8±0.2*** | 1.9±0.2** | 2.3±0.3* | 0.9±0.1** | 1.7±0.3** |
| 10 μg/mL | 1.56±0.05*** | 1.60±0.04*** | 3.5±0.3*** | 2.5±0.2*** | 3.5±0.3*** | 2.8±0.4** | 1.6±0.2*** | 2.5±0.3*** |
| 100 μg/mL | 1.34±0.04*** | Toxic | 1.1±0.6*** | Toxic | 9.1±0.2*** | Toxic | 3.7±0.6*** | Toxic |
Notes: CBPI and mitotic (cytostasis), apoptotic, and necrotic (cytotoxicity) indices scored by CBMN Cyt assay. CBPI of PBL exposed to 5 nm and 15 nm Au NPs decreased with a dose-dependent relationship (P=0.027 and P=0.02, respectively) as well as for Raw264.7 exposed to 5 nm Au NPs (P=0.04). Dose-dependent decrease in the mitotic index was observed in PBL exposed to 15 nm Au NPs (P=0.029) and in Raw264.7 exposed to 5 nm and 15 nm Au NPs (P=0.033 and P=0.05, respectively). Both PBL and Raw264.7 exposed to 15 nm Au NPs showed dose-dependent apoptotic index increase (P=0.049 and P=0.05, respectively); the necrotic index induced a dose-dependent effect in PBL exposed to 5 nm and 15 nm Au NPs (P=0.016 and P=0.03, respectively) and in Raw264.7 exposed to 15 nm Au NPs (P=0.017). 100 μg/mL 15 nm Au NPs resulted in illegible slides. Statistically significant differences from the control were determined by the Student’s t-test (*P<0.05; **P<0.01; ***P<0.001). Data represent the mean ± SEM. PBL: n=4; Raw264.7: n=6.
Abbreviations: Au NP, gold nanoparticle; C+, positive control (0.1 μg/mL MMC); C−, negative (untreated) control; CBMN Cyt, cytokinesis-block micronucleus cytome; CBPI, cytokinesis block proliferation index; MMC, mitomycin C; PBL, peripheral blood lymphocytes; SEM, standard error of the mean.