Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-1-14
pubmed:abstractText
We studied the effects of tryptophan (TRP) availability on the synthesis and release of nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha) in interferon-gamma (IFN-gamma)-activated murine macrophages of the BAC1.2F5 cell line. IFN-gamma (100 U/ml) not only increased the synthesis and release of NO and TNF-alpha from these cells but also induced indoleamine-2,3-dioxygenase, the rate-limiting enzyme of TRP catabolism. This led to an increased metabolic flow through the kynurenine pathway and significantly decreased TRP levels in macrophage incubation media. Low TRP concentrations in the media, however, modified IFN-gamma effects. In TRP-"starved" cultures, in fact, the IFN-gamma-mediated NO synthase induction was significantly reduced, and the increased TNF-alpha synthesis and release were not affected. Our results suggest that a reduced local TRP availability may modify macrophage function and possibly the outcome of immune responses.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0741-5400
pubmed:author
pubmed:issnType
Print
pubmed:volume
73
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
172-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Tryptophan availability selectively limits NO-synthase induction in macrophages.
pubmed:affiliation
Department of Preclinical and Clinical Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't