TY - JOUR
T1 - Mutagen excretion and cytochrome P-450-dependent activity in germfree and conventional rats fed a diet containing fried meat
AU - Övervik, E.
AU - Lindeskog, P.
AU - Midtvedt, T.
AU - Gustafsson, J. Å
N1 - Funding Information:
Acknowledgements--We gratefully acknowledge Ms Christina Thulin, Ms Kerstin Forsell, Ms Gunnel Alm-berger and Mr Michael Corrie for their technical assistance. This study was supported by funds from the Swedish Cancer Society, the Ekhaga Foundation, the Swedish Nutrition Foundation, Robert Lundbergs minnesfond and the Swedish Society for Medical Research.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1990
Y1 - 1990
N2 - To evaluate a possible role of the intestinal microflora in the metabolism of the highly mutagenic compounds formed in fried meat, conventional and germfree male AGUS rats were fed a semi-synthetic diet containing fried meat. Changes in mutagen excretion in urine and faeces over time were studied using the Ames Salmonella assay. The faecal and urinary extracts were separated by means of high-performance liquid chromatography (HPLC), and the mutagenicity of the collected fractions was determined. Cytochrome P-450 IA (IA1 and/or IA2) were detected by the use of antibodies with the Western blot technique, and the corresponding enzyme activities were measured in microsomes from the small intestine and the liver. A quantitative as well as qualitative difference in excretion of mutagens between germfree and conventional rats was observed. The total excreted mutagenicity was significantly higher for the conventional than for the germfree rats, as a result of a higher faecal excretion of mutagens in the conventional animals. The HPLC separations of urinary and faecal extracts showed a different mutagenic metabolite pattern between the germfree and conventional rats. An increased activity of the cytochrome P-450-dependent enzyme ethoxyresorufin-O-deethylase was observed in the small intestine of conventional rats on the fried meat diet, whereas no effect of this diet was observed in the germfree rats. Similar results were obtained in immunoblotting experiments using a P-450 IA antiserum. The present study indicates that the excretion pattern and thus also the metabolism of compounds present in fried meat are affected by the germfree status.
AB - To evaluate a possible role of the intestinal microflora in the metabolism of the highly mutagenic compounds formed in fried meat, conventional and germfree male AGUS rats were fed a semi-synthetic diet containing fried meat. Changes in mutagen excretion in urine and faeces over time were studied using the Ames Salmonella assay. The faecal and urinary extracts were separated by means of high-performance liquid chromatography (HPLC), and the mutagenicity of the collected fractions was determined. Cytochrome P-450 IA (IA1 and/or IA2) were detected by the use of antibodies with the Western blot technique, and the corresponding enzyme activities were measured in microsomes from the small intestine and the liver. A quantitative as well as qualitative difference in excretion of mutagens between germfree and conventional rats was observed. The total excreted mutagenicity was significantly higher for the conventional than for the germfree rats, as a result of a higher faecal excretion of mutagens in the conventional animals. The HPLC separations of urinary and faecal extracts showed a different mutagenic metabolite pattern between the germfree and conventional rats. An increased activity of the cytochrome P-450-dependent enzyme ethoxyresorufin-O-deethylase was observed in the small intestine of conventional rats on the fried meat diet, whereas no effect of this diet was observed in the germfree rats. Similar results were obtained in immunoblotting experiments using a P-450 IA antiserum. The present study indicates that the excretion pattern and thus also the metabolism of compounds present in fried meat are affected by the germfree status.
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U2 - 10.1016/0278-6915(90)90037-N
DO - 10.1016/0278-6915(90)90037-N
M3 - Article
C2 - 2358251
AN - SCOPUS:0025301495
VL - 28
SP - 253
EP - 261
JO - Food and Chemical Toxicology
JF - Food and Chemical Toxicology
SN - 0278-6915
IS - 4
ER -