Linked Life Data

8594414

Source:http://linkedlifedata.com/resource/pubmed/id/8594414

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-4-8
pubmed:abstractText
It is well established that exogenous RNA is incorporated into eukaryotic cells and is able to exert various biological responses. Little, however, is known about the effects of such RNA on macrophages. In this study, we demonstrate that RNA extracted from macrophages stimulated with Escherichia coli lipopolysaccharide (LPS), referred to as L-RNA, in contrast to RNA from non-stimulated macrophages (N-RNA), induces the release of a macrophage-derived neutrophil chemotactic factor (MNCF) and interleukin-8 (IL-8) from macrophage monolayers. The effect of L-RNA was dependent of the integrity of the polynucleotide chain and was not due to LPS contamination since its ability to induce MNCF and IL-8 release was strongly reduced by RNase but was not affected by DNase or polymyxin B. The poly A(+)L-RNA and poly A(-)L-RNA fractions were able to induce the release of MNCF and IL-8, indicating that the L-RNA could be acting at transcriptional and translational levels. The demonstration that actinomycin-D and cycloheximide inhibited the release of MNCF and IL-8 by L-RNA-stimulated macrophages confirms this assumption. Fractionation of the total L-RNA by centrifugation on a 5-20% sucrose gradient showed that the L-RNA which sediments in the 4-5S region of the gradient is the only fraction capable of inducing the release of MNCF from naive macrophages. We have previously shown that macrophage monolayers stimulated with interleukin-1 beta or LPS release a low molecular RNA which also sediments in the same 4-5S region. Taken together, these results support our proposal that resident macrophages, when activated by injurious stimuli, in addition to secreting cytokines, also release a low molecular weight (4-5S) RNA which may act on the surrounding macrophages to further stimulate the release of cytokines. This process would amplify the inflammatory response and would increase the mechanisms involved in the defense response or tissue injury.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0300-8177
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
105-13
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Partial characterization of the RNA from LPS-stimulated macrophages that induces the release of chemotactic cytokines by resident macrophages.
pubmed:affiliation
Department of Pharmacology, School of Medicine, University of São Paulo, Ribeirão Preto, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't