Linked Life Data

9840187

Source:http://linkedlifedata.com/resource/pubmed/id/9840187

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-12-14
pubmed:abstractText
Chronic intestinal radiation injury is associated with locally increased TGF-beta1 immunoreactivity that correlates with morphological alterations. However, the underlying mechanisms are not known. This study examined changes in intestinal TGF-beta1 immunoreactivity, steady-state TGF-beta1 mRNA levels, and cellular localization of TGF-beta1 mRNA during development of chronic radiation enteropathy in a rat model. A loop of small bowel was fixed inside the scrotum of orchiectomized male rats. The intestine was subsequently exposed locally to 0, 12 or 21 Gy X radiation. Intestine was procured at 24 h and 2, 6 and 26 weeks and subjected to histopathological analysis, quantitative immunohistochemistry with computerized image analysis, assessment of steady-state TGF-beta1 mRNA levels with quantitative reverse transcriptase polymerase chain reaction, and identification of cell types expressing TGF-beta1 mRNA with in situ hybridization. Intestine from the 21-Gy group exhibited more histopathological injury and increased TGF-beta immunoreactivity 2-26 weeks after irradiation compared to the 12-Gy group and sham-irradiated controls. TGF-beta1 mRNA in irradiated intestine increased up to six times relative to controls at 24 h and 2 weeks, was less at 6 weeks, and did not differ from controls at 26 weeks. In situ hybridization detected TGF-beta1 mRNA in epithelial and Paneth cells in control intestine. Irradiated intestine exhibited additional TGF-beta1 mRNA in inflammatory and fibroblast-like cells. We conclude that there is a radiation-induced shift in the cellular sources of TGF-beta1, and that Tgfb1 gene expression is increased mainly during the early phases of radiation enteropathy, preceding the increase in immunoreactivity and histopathological injury. Translational or post-translational mechanisms are likely involved in sustaining increased TGF-beta1 immunoreactivity levels during the chronic phase of radiation enteropathy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0033-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
150
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
673-80
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Changes in transforming growth factor beta1 gene expression and immunoreactivity levels during development of chronic radiation enteropathy.
pubmed:affiliation
Department of Surgery, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't