Table 8.
In vivo studies on OTA genotoxicity
| Test system | Animals | Concentration/Treatment | Result | Comments | Reference |
|---|---|---|---|---|---|
| SSBs by comet assays +/−Fpg (kidney) | Wistar rats (males) | 0.005, 0.05 and 0.5 mg/kg bw/15 days (oral) | Positive: all doses. SSBs increased by Fpg | Combined effects with FB1: synergistic increase in SSB | Domijan et al. (2006) |
| SSBs by comet assays in liver, kidney, lymphocytes | Sprague–Dawley rat (males) | 0.5 mg/kg bw/14 days (gavage) |
Positive: liver & kidney Negative: lymphocytes |
Protection by lycopene | Aydin et al. (2013) |
| SSBs by comet assays +/−Fpg in kidney | Fisher rats (males & females) |
0.5 mg/kg bw/7 days 0.21 and 0.5 mg/kg bw/21 days (gavage) |
Negative: in both males and females | No changes in total GST and SOD activity, total GSH and GSSG levels | Enciso et al. (2018) |
| SSBs by comet assays +/− hOGG1 in kidney and liver | Wistar rats (males) | 0.125 and 0.250 mg/kg bw/21 days (gavage) |
Negative: kidney Positive: liver (only at highest does) but no control data for comet assays are provided |
Combined effects with CTN Limited value (no controls) |
Rašić et al. (2018) |
| SSBs by comet assays in kidney | Wistar rats (female) | 0.5 mg/kg bw/7, 14, and 21 days (i.p.) | Positive | Unreliable study (0 values in controls) | Zeljezić et al. (2006) |
|
SSBs by comet assays assays +/− Fpg (kidney, liver, spleen, blood) CA in splenocytes |
Wistar rats (males) |
OTA: 0.25, 0.5, 1 and 2 mg/kg bw/2 weeks (oral) OTB: 2 mg/kg bw/2 weeks (oral) |
Positive (OTA): SSBs in kidney (all doses), liver and spleen (0.5–2 mg/kg). Increased by Fpg in liver and blood (all doses), kidney (only highest dose) Negative (OTA): CA in splenocytes (non‐significant increase) |
Increased polyploidy in renal medulla (but not in cortical regions of the kidney) OTB‐induced SSBs only in liver and spleen |
Mally et al. (2005b) |
| SSBs by comet assays in blood, micronuclei in bone marrow | BALB/c mice (males) | 0.85 mg/kg bw i.p. Analyses at 24 h |
Positive: SSBs in blood Positive: micronuclei in bone marrow |
Combined effects with Polyphenols. Limited study (single dose) | Cariddi et al. (2015) |
|
SSBs by comet assays +/− Fpg in liver and kidney Micronuclei in bone marrow |
F344 rats (males) | 0.5 mg/kg bw/3h and 24 h (oral). No clinical signs of toxicity |
Positive: SSBs in kidney (only +Fpg) Negative: SSBs in liver Negative: micronuclei |
Combined treatment with AFB1: antagonistic effects | Corcuera et al. (2015) |
| Micronuclei in bone marrow | Sprague–Dawley rats (males) | 3 mg/kg bw/15 days (oral) | Positive: single and very high dose (30% of death in OTA group) | Combined treatment with plant extracts (Inulacrithmoides). Limited study | Abdel‐Wahhab et al. (2008) |
| DSBs by γH2AX | F344 rats (males) | 0.21 mg/kg bw/28 days (gavage) | Positive: DSBs in outer stripe of outer medulla | Increased cdc‐2‐positive and P‐Chk2 cells. Karyomegaly in outer medulla | Taniai et al. (2012a) |
| CA in bone marrow | BALB/c (males) | 0.6, 1.2, and 2.4 mg/kg bw (corresponding to 2, 4, and 8% of the mouse LD50, 31 mg/kg bw) (sacrifice 24 h after single ip injection) | Positive: dose‐response increase in CA at 1.2 and 2.4 mg/kg bw (no statistical significance provided) | Bouslimi et al. (2008) | |
| Mutations in Gpt and Red/Gam genes (Spi − ) in kidney | Gpt‐delta F344 rats (males & females) | 5 ppm (gavage)/4 & 13 wks) (corresponding to 0.36–0.38 mg/kg bw/4 wks and 32.7–34 mg/kg bw/13 wks for males & females, respectively). Decreased absolute/relative kidney weights (both times) |
Negative: gpt and Spi − mutations in the whole kidney (4 and 13 wks). No changes in mutational spectra of gptmutants Positive: Spi − mutations in outer medulla, but not in inner medulla or renal cortex (4 wks) |
Karyomegaly in outer medulla (both times) No increase in DNA 8‐OHdG levels in the cortex or outer medulla (13 wks) |
Hibi et al. (2011) |
| Mutations in Gpt and Red/Gam (Spi − ) in kidney | Gpt‐delta p53+/+ and p53−/− C57BL/6J mouse | 1 and 5 mg/kg bw/4 weeks (gavage)(males). Decreased body weights & absolute/relative kidney weights (highest dose) |
Negative: no increase in mutation frequency at both loci in p53+/+ mice. No difference in mutational spectra at Gpt Positive: increased Spi ‐ mutations in p53−/− mice in outer medulla (only at 5 mg/kg bw) |
Increased p53 in p53+/+ (5 mg/kg bw). Higher levels of apoptosis & karyomegaly in p53−/− kidneys (evident also in the cortex) | Hibi et al. (2013b) |
| Mutations in Red/Gam (Spi − ) SSBs by comet assays, DSBs by γ‐H2AX (IF and western blotting) in kidney outer medulla | Gpt‐delta F344 rats (males) |
Spi‐ mutations: 5 ppm/4 weeks (0.36 mg/kg bw) SSBs & DSBs: 0.07, 0.21, 0.63 mg/kg bw/4 weeks (gavage) |
Positive: Increased Spi− mutation frequency in outer medulla (large deletions, range 1–6 kb) Positive: SSBs (all doses) Positive: DSBs (2 highest doses) |
Dose‐dependent increased expression of homologous recombination genes and genes involved in G2/M arrest and S/G2 phase | Kuroda et al. (2014) |
| Mutations in Red/Gam (Spi − ), SSBs by comet assays, DSBs by γ‐H2AX in kidney | Gpt‐delta p53+/+ and p53−/− C57BL/ 6J mouse (males) |
Spi‐ mutations &DSBs: 5 mg/kg bw/4 wks SSBs: 5 mg/kg bw/3 days (gavage) |
Positive: increased Spi‐ mutations only in p53−/− mice (single bp deletions in repetitive G/C sequences, insertions and base substitutions) Positive: SSBs (no difference p53+/+/ p53−/− mice) Positive: DSBs (preferentially in outer medulla of p53+/+ mice). Higher DSBs in p53−/− mice (also in the cortex) |
Increased apoptotic & karyomegalic cells (higher in p53−/− mice) Several differentially expressed genes affected by p53 status identified by global expression analysis by microarrays |
Kuroda et al. (2015) |
| DNA 8‐OHdG by LC/MS/MS in liver and kidney | F344 rats (males) | 0.25, 0.5, 1, 2 mg/kg bw/ 2 weeks (oral) | Negative | Increased apoptosis and polyploidy in cells of outer stripe of outer medulla | Mally et al. (2005a) |
|
Micronuclei in bone marrow 8‐OHdG by HPLC/ECD in kidney and liver |
Wistar rats (males) | 1 and 4 mg/kg bw/7 days | Negative: both micronuclei & 8‐OHdG | No consistent evidence of oxidative stress in the liver or kidney (ROS, SOD, GSH, MDA) | Zhu et al. (2016a) |
|
8‐OHdG by HPLC/ECD in kidney and liver SSB by comet assays |
Fisher 344 Rats (males) | 70 and 210 μg/kg bw/4 weeks and 13 weeks |
Positive: 8‐OHdG in liver (only at 4 weeks, both doses, no dose response) Positive: 8‐OHdG in kidney (only at 13 weeks, both doses, no dose response) |
Negative: SSB (but data not shown) | Qi et al. (2014a) |
| AP sites in kidney | Fisher 344 Rats (males) | Diet containing 300 μg//kg bw decreased to 100 μg/rat after animals reached 333 g (21 days and 12 months) |
Negative: 21 days Positive: 12 months |
Non‐standard test | Cavin et al. (2007) |
AFB1: Aflatoxin B1; AP: purinic/apyrimidinic; CA: Chromosome aberrations; CTN: citrinin; γ‐H2AX: phosphorylated form of histone protein of the H2A family formed when double‐strand breaks appear. Gpt: Glutamic‐pyruvic transaminase gene; GST: Glutathione‐S‐transferase; SOD: Superoxide dismutase; Spi: protein spitz precursor (a proto oncogene); GST: Glutathione synthetase; GSSG: Glutathione disulfide; 8‐OHdG: 8‐hydroxydeoxyguanosine; DSBs: Double strand breaks; hOR: human oxidoreductase; FB1: Fumonisin B1 ; Fpg: Fapy glycosylase gene; ROS: reactive oxygen species; MDA: Malondialdehyde; SSBs: Single strand breaks; STER: Sterigmatocystin.