Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-3-6
pubmed:abstractText
Wyeth-14,643 (WY) and ammonium perfluorooctanoate (C8) belong to a diverse class of compounds which have been shown to produce hepatic peroxisome proliferation in rodents. From previous work, WY, but not C8, has been shown to produce hepatocellular carcinoma in rats, while C8 has been shown to produce Leydig cell adenomas. In addition, based on a review of bioassay data a relationship appears to exist between peroxisome-proliferating compounds and Leydig cell adenoma and pancreatic acinar cell hyperplasia/adenocarcinoma formation. To further investigate the relationship between peroxisome-proliferating compounds and hepatic, Leydig cell, and pancreatic acinar cell tumorigenesis, a 2-year feeding study in male CD rats was initiated to test the hypothesis that peroxisome proliferating compounds induce a tumor triad (liver, Leydig cell, pancreatic acinar cell), and to examine the potential mechanism for the Leydig cell tumors. The study was conducted using 50 ppm WY and 300 ppm C8. The concentration of WY in the diet was decreased to 25 ppm on test day 301 due to increased mortality. In addition to the ad libitum control, a second control was pair-fed to the C8 group. Interim sacrifices were performed at 1- or 3-month intervals. Peroxisome proliferation measured by beta-oxidation activity and cell proliferation were measured in the liver and testis at all time points and in the pancreas beginning at the 9-month time point (cell proliferation only). Serum hormone concentrations (estradiol, testosterone, LH, FSH, and prolactin) were also measured at each time point. Increased relative liver weights and hepatic beta-oxidation activity were observed in both the WY- and C8-treated rats at all time points. In contrast, hepatic cell proliferation was significantly increased only in the WY-treated group. Neither WY nor C8 significantly altered the rate of Leydig cell beta-oxidation or Leydig cell proliferation when compared to the control groups. Moreover, the basal rate of beta-oxidation in Leydig cells was approximately 20 times less than the rate of hepatic beta-oxidation. There were no biologically meaningful differences in serum testosterone, FSH, prolactin, or LH concentrations in the WY- and C8-treated rats when compared to their respective controls. There were, however, significant increases in serum estradiol concentrations in the WY- and C8-treated rats at 1, 3, 6, 9, 15, 18, and 21 months. At 12 months, only the C8-treated rats had elevated serum estradiol concentrations when compared to the pair-fed control. Histopathological evaluation revealed compound-related increases in liver, Leydig cell, and pancreatic acinar cell tumors in both WY- and C8-treated rats. The data support the hypothesis that the peroxisome-proliferating compounds induce the previously described tumor triad. In addition, both C8 and WY produced a sustained increase in serum estradiol concentrations that correlated with the potency of the 2 compounds to induce Leydig cell tumors (i.e., WY caused a more consistent sustained increase in serum estradiol throughout the entire study, and more specifically at the end of the study, than did C8). This study suggests that estradiol may play a role in enhancement of Leydig cell tumors in the rat, and that peroxisome proliferators may induce tumors via a non-LH type mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Carcinogens, http://linkedlifedata.com/resource/pubmed/chemical/Estradiol, http://linkedlifedata.com/resource/pubmed/chemical/Fluorocarbons, http://linkedlifedata.com/resource/pubmed/chemical/Follicle Stimulating Hormone, http://linkedlifedata.com/resource/pubmed/chemical/Luteinizing Hormone, http://linkedlifedata.com/resource/pubmed/chemical/Octanoic Acids, http://linkedlifedata.com/resource/pubmed/chemical/Peroxisome Proliferators, http://linkedlifedata.com/resource/pubmed/chemical/Prolactin, http://linkedlifedata.com/resource/pubmed/chemical/Pyrimidines, http://linkedlifedata.com/resource/pubmed/chemical/Testosterone, http://linkedlifedata.com/resource/pubmed/chemical/perfluorooctanoic acid, http://linkedlifedata.com/resource/pubmed/chemical/pirinixic acid
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1096-6080
pubmed:author
pubmed:issnType
Print
pubmed:volume
60
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44-55
pubmed:dateRevised
2010-9-17
pubmed:meshHeading
pubmed-meshheading:11222872-Adenocarcinoma, pubmed-meshheading:11222872-Animals, pubmed-meshheading:11222872-Carcinogenicity Tests, pubmed-meshheading:11222872-Carcinogens, pubmed-meshheading:11222872-Cell Division, pubmed-meshheading:11222872-Diet, pubmed-meshheading:11222872-Estradiol, pubmed-meshheading:11222872-Fluorocarbons, pubmed-meshheading:11222872-Follicle Stimulating Hormone, pubmed-meshheading:11222872-Leydig Cell Tumor, pubmed-meshheading:11222872-Liver, pubmed-meshheading:11222872-Liver Neoplasms, pubmed-meshheading:11222872-Longevity, pubmed-meshheading:11222872-Luteinizing Hormone, pubmed-meshheading:11222872-Neoplasms, Experimental, pubmed-meshheading:11222872-Octanoic Acids, pubmed-meshheading:11222872-Organ Size, pubmed-meshheading:11222872-Pancreatic Neoplasms, pubmed-meshheading:11222872-Peroxisome Proliferators, pubmed-meshheading:11222872-Prolactin, pubmed-meshheading:11222872-Pyrimidines, pubmed-meshheading:11222872-Rats, pubmed-meshheading:11222872-Rats, Inbred Strains, pubmed-meshheading:11222872-Testosterone
pubmed:year
2001
pubmed:articleTitle
Mechanisms of extrahepatic tumor induction by peroxisome proliferators in male CD rats.
pubmed:affiliation
Covance Laboratories, Inc., 3301 Kinsman Boulevard, Madison, Wisconsin 53704, USA.
pubmed:publicationType
Journal Article