NFkappaB, cytokines, TLR 3 and 7 expression in human end-stage HCV and alcoholic liver disease.
OBJECTIVE
Conflicting observations exist concerning the role of nuclear factor kappa B (NFjB) in alcoholic liver disease (ALD) in animal models. To date no studies have examined this aspect in human liver tissue. We here assessed cytokines and toll-like receptors (TLRs) expressions in conjunction with NFkappaB activation in non-active end-stage human ALD compared with normal livers and hepatitis C virus (HCV) related end-stage disease.


METHODS
mRNA and protein expression were examined by quantitative PCR and Western blotting, DNA-binding by electrophoretic mobility shift assays and NFkappaB sub-cellular localization by immunofluorescent staining of livers.


RESULTS
NFkappaB mRNA and protein expression as well as strong DNA-binding were preserved in ALD but significantly down-regulated in HCV compared with normal livers. P50 immunofluorescence was found in hepatocytes and bile ducts in ALD and normal livers, whereas a shift was observed in p65 staining from non-parenchymal cells in normal livers to hepatocytes in ALD. NFkappaB responsive genes mRNA levels IkBalpha and interleukin 6 were significantly higher in ALD compared with HCV. Tumour necrosis factor alpha (TNFalpha), TLRs 3 and 7 mRNA were up-regulated in ALD and HCV compared with normal liver with TNFalpha and TLR7 being the highest in HCV. Strong induction of interferon beta was found in HCV but not in ALD or normal liver tissue.


CONCLUSIONS
Persistent NFkappaB activation together with high pro-inflammatory cytokine expression and upregulation of TLR3 and TLR7 is associated with end-stage ALD in humans and could contribute to disease progression even in absence of alcohol intake.
Stärkel
Peter
P
Department of Gastroenterology, St. Luc University Hospital, Catholic University of Louvain, Brussels, Belgium. peter.starkel@uclouvain.be
De Saeger
Christine
C
Strain
Alastair J
AJ
Leclercq
Isabelle
I
Horsmans
Yves
Y
D015153:Blotting, Western; D016207:Cytokines / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D015536:Down-Regulation; D019698:Hepatitis C, Chronic / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008108:Liver Diseases, Alcoholic / Q000378:metabolism* / Q000473:pathology; D016328:NF-kappa B / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051196:Toll-Like Receptor 3 / Q000378:metabolism*; D051199:Toll-Like Receptor 7 / Q000378:metabolism; D015854:Up-Regulation
D016207:Cytokines; D004268:DNA-Binding Proteins; D015850:Interleukin-6; D016328:NF-kappa B; D012333:RNA, Messenger; C495344:TLR3 protein, human; C495348:TLR7 protein, human; D051196:Toll-Like Receptor 3; D051199:Toll-Like Receptor 7