NTP technical report on the toxicology studies of green tea extract in f344/NTac rats and B6C3F1/N mice and toxicology and carcinogenesis studies of green tea extract in wistar han [Crl:WI(Han)] rats and B6C3F1/N mice (Gavage studies)
CONCLUSIONS: Under the conditions of these 2-year gavage studies, there was no evidence of carcinogenic activity (see Explanation of Levels of Evidence of Carcinogenic Activity; see a summary of the peer review panel comments and the public discussion on this Technical Report in Appendix L) of green...
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| Format: | eBook |
| Language: | English |
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Research Triangle Park, North Carolina, USA
National Toxicology Program, Public Health Service, U.S. Department of Health and Human Services
2016, April 2016
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| Series: | Technical report
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| Online Access: | |
| Collection: | National Center for Biotechnology Information - Collection details see MPG.ReNa |
| Summary: | CONCLUSIONS: Under the conditions of these 2-year gavage studies, there was no evidence of carcinogenic activity (see Explanation of Levels of Evidence of Carcinogenic Activity; see a summary of the peer review panel comments and the public discussion on this Technical Report in Appendix L) of green tea extract in male or female Wistar Han rats administered 100, 300, or 1,000\smg/kg. There was no evidence of carcinogenic activity of green tea extract in male or female B6C3F1/N mice administered 30, 100, or 300 mg/kg. Administration of green tea extract resulted in increased incidences of nonneoplastic lesions of the liver, glandular stomach, small intestine (duodenum, ileum, and jejunum), nose, lung, heart, and spleen in male and female rats; bone marrow of female rats; the nose, mandibular lymph node, and bone marrow of male and female mice; and the liver of male mice. Synonyms: Green tea catechin polyphenols; green tea; green tea polyphenols THREE-MONTH STUDY IN F344/NTAC RATS: Groups of 10 male and 10 female core study rats were administered 0, 62.5, 125, 250, 500, or 1,000 mg green tea extract/kg body weight in deionized water by gavage, 5 days per week for 14\sweeks. Groups of 10 male and 10 female clinical pathology study rats were administered the same doses for 23 days. One 125 mg/kg female died during week 7. Mean body weights of males\sand females administered 250 mg/kg or greater were significantly less than those of the vehicle controls. The cauda epididymis, epididymis, and testes weights of 1,000 mg/kg males were significantly less than those of the vehicle controls. Females administered 1,000 mg/kg had longer estrous cycles and spent significantly more time in extended diestrus than did the vehicle controls. These data indicate that green tea extract exhibited the potential to be a reproductive toxicant in male and female F344/NTac rats. Several nonneoplastic liver lesions were observed in three of ten 1,000 mg/kg females. Lesions included hepatocyte necrosis, bile duct hyperplasia, oval cell hyperplasia, and mitosis. There were significant increases in the incidences of several nonneoplastic lesions in the nose of 1,000\smg/kg males and females including inflammation (females); hyperplasia in the Bowman's gland of the olfactory epithelium; nerve atrophy; and atrophy, metaplasia, and pigmentation in the olfactory epithelium; the increased incidences of inflammation (females), nerve atrophy, and olfactory epithelium metaplasia and pigmentation (males) were also significant in the 500 mg/kg groups. The incidences of histiocyte cellular infiltration in the mesenteric lymph node in 125\smg/kg or greater males were significantly increased compared to that in the vehicle control\sgroup. |
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| Physical Description: | 1 PDF file (various pagings) illustrations |