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Diphenyl diselenide supplementation delays the development of N-nitroso-N-methylurea-induced mammary tumors

Archive für Toxikologie (Impact Factor: 5.08). 09/2008; 82(9):655-663. DOI: 10.1007/s00204-007-0271-9

ABSTRACT The effect of dietary diphenyl diselenide (1ppm) on N-nitroso-N-methylurea (NMU)-induced mammary carcinogenesis was examined in female Wistar rats. Beginning at 5weeks of age, the animals
were fed with either control or diphenyl-diselenide-supplied diets until the end of the study (210days). At 50days of age,
mammary tumor was induced by the administration of three doses of NMU (50mg/kg body wt, intraperitoneally) once a week for
3weeks. In experimental trials, latency to tumor onset was extended in rats fed with diet supplemented with diphenyl diselenide
(P<0.05). The incidence and frequency of tumors were significantly small in animals supplemented with diphenyl diselenide.
However, the multiplicity of tumors was not altered by dietary diphenyl diselenide. Diphenyl diselenide supplementation also
restored superoxide dismutase (SOD) activity and vitamin C levels altered in the NMU group (P<0.05). Our results suggest that diphenyl diselenide can be considered a chemopreventive agent, even when supplemented at
a relatively low concentration.

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