S-ALLYL CYSTEINE INHIBITS ACTIVATION OF NUCLEAR FACTOR-KAPPA-B IN HUMAN T-CELLS

Reactive oxygen species are involved in signal transduction pathways l eading to nuclear factor kappa B (NF-kappa B) activation which has bee n implicated in the regulation of gene transcription. We recently repo rted that a garlic compound, S-allyl cysteine (SAC), protects bovine p ulmonary artery endothelial cells from oxidant injury induced by hydro gen peroxide (H2O2). In this study we determined the effects of SAC on NF-kappa B activation in human T lymphocytes (Jurkat cells) induced b y tumor necrosis factor alpha (TNF-alpha) and H2O2. Activated NF-kappa B in nuclear extracts was measured by an electrophoretic mobility shi ft assay using P-32-labeled probe. SAC consistently exhibited a dose-d ependent inhibition of NF-kappa B activation induced by both TNF-alpha and H2O2. Supershift with specific antibodies to NF-kappa B subunits confirmed that the inducible retarded bands observed in the EMSA are p 65-p50 heterodimer of the NF-kappa B/Rel protein. Our data suggest tha t SAC may act via antioxidant mechanisms to block NF-kappa B activatio n in Jurkat cells. (C) 1997 Elsevier Science Inc.