Title

Acute alcohol exposure exerts anti-inflammatory effects by inhibiting IkappaB kinase activity and p65 phosphorylation in human monocytes

UMMS Affiliation

Department of Medicine, Rheumatology Division; Department of Medicine, Division of Gastroenterology

Publication Date

2007-06-06

Document Type

Article

Subjects

Animals; Antigens, CD14; CHO Cells; Cricetinae; Cricetulus; Cyclic AMP-Dependent Protein Kinases; Ethanol; Humans; I-kappa B Kinase; Inflammation; Lipopolysaccharides; Monocytes; NF-kappa B; Phosphorylation; Transcription Factor RelA

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Acute alcohol use is associated with impaired immune responses and decreased proinflammatory cytokine production. Our earlier studies have shown that acute alcohol intake inhibits NF-kappaB DNA binding in an IkappaBalpha-independent manner. We report using human peripheral blood monocytes and Chinese hamster ovary cells transfected with CD14 cells that acute alcohol treatment in vitro exerts NF-kappaB inhibition by disrupting phosphorylation of p65. Immunoprecipitation of p65 and IkappaBalpha revealed that acute alcohol exposure for 1 h decreased NF-kappaB-IkappaBalpha complexes in the cytoplasm. Phosphorylation of p65 at Ser(536) is mediated by IkappaB kinase (IKK)beta and is required for NF-kappaB-dependent cellular responses. We show that acute alcohol treatment decreased LPS-induced IKKalpha and IKKbeta activity resulting in decreased phosphorylation of p65 at Ser(536). Furthermore, nuclear expression of IKKalpha increased after alcohol treatment, which may contribute to inhibition of NF-kappaB. Decreased phosphorylation of nuclear p65 at Ser(276) was likely not due to alcohol-induced inhibition of protein kinase A and mitogen- and stress-activated protein kinase-1 activity. Although decreased IkappaBalpha phosphorylation after acute alcohol treatment was attributable to reduced IKKbeta activity, degradation of IkappaBalpha during alcohol exposure was IKKbeta-independent. Alcohol-induced degradation of IkappaBalpha in the presence of a 26S proteasome inhibitor suggested proteasome-independent IkappaBalpha degradation. Collectively, our studies suggest that acute alcohol exposure modulates IkappaBalpha-independent NF-kappaB activity primarily by affecting phosphorylation of p65. These findings further implicate an important role for IKKbeta in the acute effects of alcohol in immune cells.

DOI of Published Version

10.4049/jimmunol.178.12.7686

Source

J Immunol. 2007 Jun 15;178(12):7686-93.

Journal/Book/Conference Title

Journal of immunology (Baltimore, Md. : 1950)

Related Resources

Link to Article in PubMed

PubMed ID

17548605

Share

COinS