Linked Life Data

19669731

Source:http://linkedlifedata.com/resource/pubmed/id/19669731

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2009-10-9
pubmed:abstractText
It was recently shown that 1-year chronic exposure of rats to tocotrienol (TT) induced highly proliferative liver lesions, nodular hepatocellular hyperplasia (NHH), and independently increased the number of glutathione S-transferase placental form (GST-P)-positive hepatocytes. Focusing attention on the pathological intrinsic property of NHH, a 104-week carcinogenicity study was performed in male and female Wistar Hannover rats given TT at concentrations of 0, 0.4 or 2% in the diet. The high-dose level was adjusted to 1% in both sexes from week 51 because the survival rate of the high-dose males dropped to 42% by week 50. At necropsy, multiple cyst-like nodules were observed, as in the chronic study, but were further enlarged in size, which consequently formed a protuberant surface with a partly pedunculated shape in the liver at the high dose in both sexes. Unlike the chronic study, NHH was not always accompanied by spongiosis, and instead angiectasis was prominent in some nodules. However, several findings in the affected hepatocytes such as minimal atypia, no GST-P immunoreactivity and heterogeneous proliferation, implied that NHH did not harbor neoplastic characteristics from increased exposure despite sustained high cell proliferation. On the other hand, in the high-dose females, the incidence of hepatocellular adenomas was significantly higher than in the control. There was no TT treatment-related tumor induction in any other organs besides the liver. Thus, the overall data clearly suggested that NHH is successively enlarged by further long-term exposure to TT, but does not become neoplastic. In contrast, TT induces low levels of hepatocellular adenomas in female rats.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1432-0738
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1021-30
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Simultaneous induction of non-neoplastic and neoplastic lesions with highly proliferative hepatocytes following dietary exposure of rats to tocotrienol for 2 years.
pubmed:affiliation
Division of Pathology, National Institute of Health Sciences, Setagaya-ku, Tokyo, 158-8501, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't