NO-aspirin protects from T cell-mediated liver injury by inhibiting caspase-dependent processing of Th1-like cytokines.
OBJECTIVE
Concanavalin A (con A)-induced hepatitis is an immunomediated disease in which assembly of CD4(+) T cells and T helper (Th)1-like cytokines causes Fas-mediated liver cell death. Nitric oxide (NO) modulates Th1 response in vitro. NCX-4016 is an NO-aspirin derivative that spares the gastrointestinal tract and shares molecular targets with NO. The aim of this study was to investigate whether this NO-aspirin modulates Th1-like response induced by con A.


METHODS
BALB/c mice were injected with 0.3 mg con A per mouse alone or in combination with NO-aspirin (18-100 mg/kg) or aspirin (10-55 mg/kg).


RESULTS
NO-aspirin, but not aspirin, caused a dose-dependent protection against liver damage induced by con A. At a dose of 100 mg/kg, NO-aspirin caused a 40%-80% reduction of interleukin (IL)-1beta, IL-12, IL-18, interferon (IFN)-gamma, and tumor necrosis factor alpha production without affecting cytokine messenger RNA expression. NO-aspirin prevented Fas, Fas ligand, and IL-2 receptor up-regulation on spleen lymphocytes and Fas ligand on hepatocytes and caused the S-nitrosylation/inhibition of IL-1beta-converting enzyme-like cysteine proteases (caspases) involved in the processing and maturation of IL-1beta and IL-18. IL-18 immunoneutralization prevented IFN-gamma release and protected from liver injury induced by con A. In contrast to a selective caspase 1 inhibitor, zVAD.FMK, a pancaspase inhibitor, prevented IFN-gamma release and protected the liver from injury.


CONCLUSIONS
Th1-like response induced by con A is mediated by IL-18 and requires activation of multiple caspases. NCX-4016 causes the S-nitrosylation/inhibition of caspases involved in cytokine production. Inhibition of Th1-like response is a new anti-inflammatory mechanism of action of NO-aspirin.
Fiorucci
S
S
Dipartimento di Medicina Clinica e Sperimentale, Clinica di Gastroenterologia ed Epatologia, Università degli Studi di Perugia, Perugia, Italy. icinfi@tin.it
Santucci
L
L
Antonelli
E
E
Distrutti
E
E
Del Sero
G
G
Morelli
O
O
Romani
L
L
Federici
B
B
Del Soldato
P
P
Morelli
A
A
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D001241:Aspirin / Q000031:analogs & derivatives* / Q000494:pharmacology; D020170:Caspase 1 / Q000378:metabolism; D053148:Caspase 3; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D056486:Chemical and Drug Induced Liver Injury / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control; D003208:Concanavalin A / Q000633:toxicity*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D053222:Fas Ligand Protein; D007371:Interferon-gamma / Q000096:biosynthesis; D020382:Interleukin-18 / Q000502:physiology; D007378:Interleukins / Q000096:biosynthesis; D008099:Liver / Q000187:drug effects / Q000276:immunology / Q000473:pathology*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D015375:Receptors, Interleukin-2 / Q000235:genetics; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology*; D014158:Transcription, Genetic / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects; D019014:fas Receptor / Q000235:genetics
D000590:Amino Acid Chloromethyl Ketones; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D016207:Cytokines; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D020382:Interleukin-18; D007378:Interleukins; D008562:Membrane Glycoproteins; D010975:Platelet Aggregation Inhibitors; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D019014:fas Receptor; C098312:nitroxy-butyl-acetylsalicylic acid; D003208:Concanavalin A; D007371:Interferon-gamma; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D020170:Caspase 1; C102148:nitroaspirin; D001241:Aspirin