In vivo genotoxicity and DNA adduct levels in the liver of rats treated with safrole.

The induction of chromosome aberrations, sister chromatid exchanges (SCEs), and the formation of DNA adducts was studied in hepatocytes of F344 rats exposed in vivo to safrole. Hepatocytes were isolated 24 h after a single dose of safrole or five repeated doses (once a day) by gastric intubation and allowed to proliferate in Williams' medium E supplemented with epidermal growth factor. Cells were fixed after 48 h in culture. Safrole-DNA adducts were detected by a nuclease P1-enhanced 32P-post-labeling assay in isolated hepatocytes from the rats. While a single dose was not sufficient to induce detectable levels of chromosome aberrations at the time of assay, five repeated doses induced these changes with a maximum frequency of 13.4%, compared with the control value of 1.8%. Both a single dose and five repeated doses induced significant SCEs, to a maximum frequency of 0.81 SCEs per chromosome, while the control value was 0.59 SCEs per chromosome. Two major and two minor DNA adducts were detected after treatment with either a single dose or five repeated doses. The maximum amount of total DNA adducts was 89.8 DNA adducts/10(7) nucleotides. These results show that safrole is a genotoxic carcinogen in the rat liver in vivo and suggest that the cytogenetic effects of this compound may result from covalent DNA modification in the rat liver. This in vivo cytogenetic assay should provide a useful means of evaluation of the genotoxicity of hepatocarcinogens.

[1]  S. Yuspa,et al.  Chemical carcinogenesis: from animal models to molecular models in one decade. , 1988, Advances in cancer research.

[2]  C. Ioannides,et al.  Safrole: its metabolism, carcinogenicity and interactions with cytochrome P-450. , 1981, Food and cosmetics toxicology.

[3]  J. Ashby,et al.  Evaluation of short-term tests for carcinogens , 1988 .

[4]  A. Tates,et al.  The role of specific DNA adducts in the induction of micronuclei by N-hydroxy-2-acetylaminofluorene in rat liver in vivo. , 1989, Carcinogenesis.

[5]  S S Epstein,et al.  Detection of chemical mutagens by the dominant lethal assay in the mouse. , 1972, Toxicology and applied pharmacology.

[6]  F. Homburger,et al.  Toxic and possible carcinogenic effects of 4-allyl-1,2-methylenedioxybenzene (Safrole) in rats on deficient diets. , 1961, Medicina experimentalis : International journal of experimental medicine.

[7]  L. Lu,et al.  32P-postlabeling assay in mice of transplacental DNA damage induced by the environmental carcinogens safrole, 4-aminobiphenyl, and benzo(a)pyrene. , 1986, Cancer research.

[8]  G. Wogan,et al.  Chemical and biochemical dosimetry of exposure to genotoxic chemicals. , 1985, Environmental health perspectives.

[9]  D. Doolittle,et al.  A comparative study of hepatic DNA repair, DNA replication and hepatotoxicity in the CD-1 mouse following multiple administrations of dimethylnitrosamine. , 1987, Mutation research.

[10]  G. Burdock,et al.  Fenaroli's Handbook of Flavor Ingredients , 1997 .

[11]  K. V. van Golen,et al.  Formation and persistence of safrole-DNA adducts over a 10,000-fold dose range in mouse liver. , 1993, Carcinogenesis.

[12]  T. Matsushima,et al.  Chromosome aberrations, micronuclei and sister-chromatid exchanges (SCEs) in rat liver induced in vivo by hepatocarcinogens including heterocyclic amines. , 1991, Mutation research.

[13]  E C Miller,et al.  Strong evidence from studies with brachymorphic mice and pentachlorophenol that 1'-sulfoöxysafrole is the major ultimate electrophilic and carcinogenic metabolite of 1'-hydroxysafrole in mouse liver. , 1983, Cancer research.

[14]  S. Nesnow,et al.  Formation and persistence of novel benzo(a)pyrene adducts in rat lung, liver, and peripheral blood lymphocyte DNA. , 1990, Cancer research.

[15]  A. A. Nelson,et al.  Liver tumours produced in rats by feeding safrole. , 1963 .

[16]  J. Topham.  Do induced sperm-head abnormalities in mice specifically identify mammalian mutagens rather than carcinogens? , 1980, Mutation research.

[17]  K. Hemminki,et al.  DNA adducts, mutations and cancer. , 1993, Carcinogenesis.

[18]  P. Seglen.  Preparation of isolated rat liver cells. , 1976, Methods in cell biology.

[19]  S. Thorgeirsson,et al.  In vivo mutagenicity and DNA adduct levels of heterocyclic amines in Muta mice and c-myc/lacZ double transgenic mice. , 1996, Mutation research.

[20]  B. Butterworth,et al.  Detection of genotoxic carcinogens in the in vivo-in vitro hepatocyte DNA repair assay. , 1982, Environmental mutagenesis.

[21]  G. Talaska,et al.  The correlation between DNA adducts and chromosomal aberrations in the target organ of benzidine exposed, partially-hepatectomized mice. , 1987, Carcinogenesis.

[22]  K Randerath,et al.  32P-post-labelling analysis of DNA adducts formed in the livers of animals treated with safrole, estragole and other naturally-occurring alkenylbenzenes. II. Newborn male B6C3F1 mice. , 1984, Carcinogenesis.

[23]  J. Miller,et al.  1'-Hydroxysafrole, a proximate carcinogenic metabolite of safrole in the rat and mouse. , 1973, Cancer research.

[24]  J. Spalding,et al.  Evaluation of the potential of riddelliine to induce unscheduled DNA synthesis, S‐phase synthesis, or micronuclei following in vivo treatment with multiple doses , 1993, Environmental and molecular mutagenesis.

[25]  E. Gocke,et al.  Mutagenicity of cosmetics ingredients licensed by the European Communities. , 1981, Mutation research.

[26]  M. V. Reddy,et al.  Nuclease P1-mediated enhancement of sensitivity of 32P-postlabeling test for structurally diverse DNA adducts. , 1986, Carcinogenesis.

[27]  R. Gupta,et al.  32P-postlabeling analysis of non-radioactive aromatic carcinogen--DNA adducts. , 1982, Carcinogenesis.