Evaluation of in vivo genotoxicity induced by N-ethyl-N-nitrosourea, benzo[a]pyrene, and 4-nitroquinoline-1-oxide in the Pig-a and gpt assays

Katsuyoshi Horibata, Akiko Ukai, Takafumi Kimoto, Tetsuya Suzuki, Nagisa Kamoshita, Kenichi Masumura, Takehiko Nohmi, Masamitsu Honma

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

The recently developed Pig-a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor-deficient red blood cells caused by a forward mutation in the Pig-a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig-a assay could be integrated into repeat-dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig-a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N-ethyl-N-nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4-nitroquinoline-1-oxide (4NQO, 50 mg/kg) in the Pig-a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig-a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7-week terminal sacrifice. ENU increased both Pig-a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig-a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two- or threefold above control) were detected in the bone marrow in both the Pig-a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig-a mutation assay in order to use it as an alternative to the TGR mutation assay.

Original languageEnglish
Pages (from-to)747-754
Number of pages8
JournalEnvironmental and Molecular Mutagenesis
Volume54
Issue number9
DOIs
Publication statusPublished - 2013 Dec 1
Externally publishedYes

Fingerprint

4-Nitroquinoline-1-oxide
Ethylnitrosourea
Benzo(a)pyrene
Swine
Mutation
Rodentia
Bone Marrow
Glycosylphosphatidylinositols
Liver
Toxicology
Genes
Erythrocytes

Keywords

  • Genotoxicity
  • Glycosylphosphatidylinositol anchor
  • Red blood cells
  • Transgenic rodent mutation assays

ASJC Scopus subject areas

  • Epidemiology
  • Genetics(clinical)
  • Health, Toxicology and Mutagenesis

Cite this

Evaluation of in vivo genotoxicity induced by N-ethyl-N-nitrosourea, benzo[a]pyrene, and 4-nitroquinoline-1-oxide in the Pig-a and gpt assays. / Horibata, Katsuyoshi; Ukai, Akiko; Kimoto, Takafumi; Suzuki, Tetsuya; Kamoshita, Nagisa; Masumura, Kenichi; Nohmi, Takehiko; Honma, Masamitsu.

In: Environmental and Molecular Mutagenesis, Vol. 54, No. 9, 01.12.2013, p. 747-754.

Research output: Contribution to journalArticle

Horibata, Katsuyoshi ; Ukai, Akiko ; Kimoto, Takafumi ; Suzuki, Tetsuya ; Kamoshita, Nagisa ; Masumura, Kenichi ; Nohmi, Takehiko ; Honma, Masamitsu. / Evaluation of in vivo genotoxicity induced by N-ethyl-N-nitrosourea, benzo[a]pyrene, and 4-nitroquinoline-1-oxide in the Pig-a and gpt assays. In: Environmental and Molecular Mutagenesis. 2013 ; Vol. 54, No. 9. pp. 747-754.
@article{3f4a15b9a94b42f2a09483bf37e49815,
title = "Evaluation of in vivo genotoxicity induced by N-ethyl-N-nitrosourea, benzo[a]pyrene, and 4-nitroquinoline-1-oxide in the Pig-a and gpt assays",
abstract = "The recently developed Pig-a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor-deficient red blood cells caused by a forward mutation in the Pig-a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig-a assay could be integrated into repeat-dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig-a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N-ethyl-N-nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4-nitroquinoline-1-oxide (4NQO, 50 mg/kg) in the Pig-a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig-a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7-week terminal sacrifice. ENU increased both Pig-a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig-a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two- or threefold above control) were detected in the bone marrow in both the Pig-a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig-a mutation assay in order to use it as an alternative to the TGR mutation assay.",
keywords = "Genotoxicity, Glycosylphosphatidylinositol anchor, Red blood cells, Transgenic rodent mutation assays",
author = "Katsuyoshi Horibata and Akiko Ukai and Takafumi Kimoto and Tetsuya Suzuki and Nagisa Kamoshita and Kenichi Masumura and Takehiko Nohmi and Masamitsu Honma",
year = "2013",
month = "12",
day = "1",
doi = "10.1002/em.21818",
language = "English",
volume = "54",
pages = "747--754",
journal = "Environmental and Molecular Mutagenesis",
issn = "0893-6692",
publisher = "John Libbey Eurotext",
number = "9",

}

TY - JOUR

T1 - Evaluation of in vivo genotoxicity induced by N-ethyl-N-nitrosourea, benzo[a]pyrene, and 4-nitroquinoline-1-oxide in the Pig-a and gpt assays

AU - Horibata, Katsuyoshi

AU - Ukai, Akiko

AU - Kimoto, Takafumi

AU - Suzuki, Tetsuya

AU - Kamoshita, Nagisa

AU - Masumura, Kenichi

AU - Nohmi, Takehiko

AU - Honma, Masamitsu

PY - 2013/12/1

Y1 - 2013/12/1

N2 - The recently developed Pig-a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor-deficient red blood cells caused by a forward mutation in the Pig-a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig-a assay could be integrated into repeat-dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig-a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N-ethyl-N-nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4-nitroquinoline-1-oxide (4NQO, 50 mg/kg) in the Pig-a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig-a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7-week terminal sacrifice. ENU increased both Pig-a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig-a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two- or threefold above control) were detected in the bone marrow in both the Pig-a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig-a mutation assay in order to use it as an alternative to the TGR mutation assay.

AB - The recently developed Pig-a mutation assay is based on flow cytometric enumeration of glycosylphosphatidylinositol (GPI) anchor-deficient red blood cells caused by a forward mutation in the Pig-a gene. Because the assay can be conducted in nontransgenic animals and the mutations accumulate with repeat dosing, we believe that the Pig-a assay could be integrated into repeat-dose toxicology studies and provides an alternative to transgenic rodent (TGR) mutation assays. The capacity and characteristics of the Pig-a assay relative to TGR mutation assays, however, are unclear. Here, using transgenic gpt delta mice, we compared the in vivo genotoxicity of single oral doses of N-ethyl-N-nitrosourea (ENU, 40 mg/kg), benzo[a]pyrene (BP, 100 and 200 mg/kg), and 4-nitroquinoline-1-oxide (4NQO, 50 mg/kg) in the Pig-a (peripheral blood) and gpt (bone marrow and liver) gene mutation assays. Pig-a assays were conducted at 2, 4, and 7 weeks after the treatment, while gpt assays were conducted on tissues collected at the 7-week terminal sacrifice. ENU increased both Pig-a and gpt mutant frequencies (MFs) at all sampling times, and BP increased MFs in both assays but the Pig-a MFs peaked at 2 weeks and then decreased. Although 4NQO increased gpt MFs in the liver, only weak, nonsignificant increases (two- or threefold above control) were detected in the bone marrow in both the Pig-a and the gpt assay. These findings suggest that further studies are needed to elucidate the kinetics of the Pig-a mutation assay in order to use it as an alternative to the TGR mutation assay.

KW - Genotoxicity

KW - Glycosylphosphatidylinositol anchor

KW - Red blood cells

KW - Transgenic rodent mutation assays

UR - http://www.scopus.com/inward/record.url?scp=84887182267&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84887182267&partnerID=8YFLogxK

U2 - 10.1002/em.21818

DO - 10.1002/em.21818

M3 - Article

C2 - 24105957

AN - SCOPUS:84887182267

VL - 54

SP - 747

EP - 754

JO - Environmental and Molecular Mutagenesis

JF - Environmental and Molecular Mutagenesis

SN - 0893-6692

IS - 9

ER -