Linked Life Data

19561104

Source:http://linkedlifedata.com/resource/pubmed/id/19561104

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-7-7
pubmed:abstractText
Impaired host defense after alcohol use is linked to altered cytokine production, however, acute and chronic alcohol differently modulate monocyte/macrophage activation. We hypothesized that in human monocytes, acute alcohol induces hyporesponsiveness to LPS, resulting in decreased TNF-alpha, whereas chronic alcohol increases TNF-alpha by sensitization to LPS. We found that acute alcohol increased IL-1R-associated kinase-monocyte (IRAK-M), a negative regulator of IRAK-1, in human monocytes. This was associated with decreased IkappaB alpha kinase activity, NFkappaB DNA binding, and NFkappaB-driven reporter activity after LPS stimulation. In contrast, chronic alcohol decreased IRAK-M expression but increased IRAK-1 and IKK kinase activities, NFkappaB DNA binding, and NFkappaB-reporter activity. Inhibition of IRAK-M in acute alcohol-exposed monocytes using small interfering RNA restored the LPS-induced TNF-alpha production whereas over-expression of IRAK-M in chronic alcohol macrophages prevented the increase in TNF-alpha production. Addition of inhibitors of alcohol metabolism did not alter LPS signaling and TNF-alpha production during chronic alcohol exposure. IRAK-1 activation induces MAPKs that play an important role in TNF-alpha induction. We determined that acute alcohol decreased but chronic alcohol increased activation of ERK in monocytes and ERK inhibitor, PD98059, prevented the chronic alcohol-induced increase in TNF-alpha. In summary, inhibition of LPS-induced NFkappaB and ERK activation by acute alcohol leads to hyporesponsiveness of monocytes to LPS due to increased IRAK-M. In contrast, chronic alcohol sensitizes monocytes to LPS through decreased IRAK-M expression and activation of NFkappaB and ERK kinases. Our data indicate that IRAK-M is a central player in the opposite regulation of LPS signaling by different lengths of alcohol exposure in monocytes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1550-6606
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
183
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1320-7
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
The opposite effects of acute and chronic alcohol on lipopolysaccharide-induced inflammation are linked to IRAK-M in human monocytes.
pubmed:affiliation
University of Massachusetts Medical School, Department of Medicine, Worcester, MA 01605, USA. pranoti.mandrekar@umassmed.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural