Ethanol and Arachidonic Acid Synergize to Activate Kupffer Cells and Modulate the Fibrogenic Response via Tumor Necrosis Factor , Reduced Glutathione, and Transforming Growth Factor beta–Dependent Mechanisms
Loading...
Full text at PDC
Publication date
2008
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Lippincott, Williams & Wilkins
Citations
Exportar
Citation
Cubero FJ, Nieto N. Ethanol and arachidonic acid synergize to activate Kupffer cells and modulate the fibrogenic response via tumor necrosis factor alpha, reduced glutathione, and transforming growth factor beta-dependent mechanisms. Hepatology. 2008 Dec;48(6):2027-2039. doi: 10.1002/hep.22592. PMID: 19003881; PMCID: PMC4477289.
Abstract
Because of the contribution of ethanol and polyunsaturated fatty acids (PUFAs) to alcoholic liver disease, we investigated whether chronic ethanol administration and arachidonic acid (AA) could synergistically mediate Kupffer cell (KC) activation and modulate the stellate cell (HSC) fibrogenic response.
Results: (1) the effects of ethanol and AA on KC and HSC were as follows: Cell proliferation, lipid peroxidation, H(2)O(2), O(2).(-), nicotinamide adenine dinucleotide phosphate reduced form (NADPH) oxidase activity, and tumor necrosis factor alpha (TNF-alpha) were higher in KC(ethanol) than in KC(control), and were enhanced by AA; HSC(ethanol) proliferated faster, increased collagen, and showed higher GSH than HSC(control), with modest effects by AA. (2) AA effects on the control co-culture: We previously reported the ability of KC to induce a pro-fibrogenic response in HSC via reactive oxygen species (ROS)-dependent mechanisms; we now show that AA further increases cell proliferation and collagen in the control co-culture. The latter was prevented by vitamin E (an antioxidant) and by diphenyleneiodonium (a NADPH oxidase inhibitor). (3) Ethanol effects on the co-cultures: Co-culture with KC(control) or KC(ethanol) induced HSC(control) and HSC(ethanol) proliferation; however, the pro-fibrogenic response in HSC(ethanol) was suppressed because of up-regulation of TNF-alpha and GSH, which was prevented by a TNF-alpha neutralizing antibody (Ab) and by L-buthionine-sulfoximine, a GSH-depleting agent. (4) Ethanol plus AA effects on the co-cultures: AA lowered TNF-alpha in the HSC(control) co-cultures, allowing for enhanced collagen deposition; furthermore, AA restored the pro-fibrogenic response in the HSC(ethanol) co-cultures by counteracting the up-regulation of TNF-alpha and GSH with a significant increase in GSSG and in pro-fibrogenic transforming growth factor beta (TGF-beta).
Conclusion: These results unveil synergism between ethanol and AA to the mechanism whereby KC mediate ECM remodeling and suggest that even if chronic ethanol consumption sensitizes HSC to up-regulate anti-fibrogenic signals, their effects are blunted by a second "hit" such as AA.
Description
Abbreviations: alpha-SMA, alpha-smooth muscle actin; AA, arachidonic acid; DPI, diphenyleneiodonium; ECM, extracellular matrix; GSH, reduced glutathione; GSSG,
oxidized glutathione; HSC, hepatic stellate cells; HSCcontrol, control stellate cells; HSCethanol, stellate cells from ethanol-fed rats; KC, Kupffer cells; KCcontrol, control Kupffer
cells; KCethanol, Kupffer cells from ethanol-fed rats; PUFA, polyunsaturated fatty acids; NADPH, nicotinamide adenine dinucleotide phosphate reduced form; ROS, reactive
oxygen species; SEM, standard error of the mean; TGF- , transforming growth factor beta; TNF- , tumor necrosis factor alpha.
From the Department of Medicine, Division of Liver Diseases, Mount Sinai School of Medicine, New York, NY.
Both authors contributed equally to the experimental part of this work
Received June 7, 2008; accepted August 4, 2008.
Supported by a Postdoctoral Fellowship from the Spanish Ministry of Education and Science Ref. No. EX2006-0070 (F.J.C) and by the US Public Health Service Grant
5R01DK069286-03 from the National Institute of Diabetes and Digestive and Kidney Diseases (N.N.).
Address reprint requests to: Natalia Nieto, Department of Medicine, Division of Liver Diseases, Mount Sinai School of Medicine, Box 1123, 1425 Madison Avenue,
Room 11-76, New York, NY 10029. E-mail: natalia.nieto@mssm.edu; fax: 212-849-2574.
Copyright © 2008 by the American Association for the Study of Liver Diseases.
Published online in Wiley InterScience (www.interscience.wiley.com).
DOI 10.1002/hep.22592
Potential conflict of interest: Nothing to report.
Additional Supporting Information may be found in the online version of this article.