Vitamin E and NF-κB Activation: A Review

Nuclear factor (NF-κB)¹1Abbreviations: DEM, diethyl maleate; DSS, dextran sulfate sodium; EGF, epidermal growth factor; EPC-K1, phosphate diester linkage of vitamins E and C; EPU, phosphodiester linkage of vitamin E and uracil; GFP, green fluorescent protein; HCH, γ-hexachlorocyclohexane; HIV, human immunodeficiency virus; IFN, interferon; IRFI-016, 2,3-dihydro-5-acetyloxy-4,6,7-trimethyl-2-benzofuranacetic acid; IRFI-042, butanedioic acid, mono[2-[2-(acetylthio)ethyl]-2,3-dihydro-4,6,7-trimethyl-5-benzofuranyl] ester, (±)-; IKK, IκB kinase; IL, interleukin; LDL, low-density lipoprotein; LPS, lipopolysaccharide; LTR, long terminal repeat; MitoVit E, [2-(3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-yl)ethyl]triphenylphosphonium bromide; NAC, N-acetyl cysteine; NF-κB, nuclear factor-κB; PAF, platelet-activating factor; PCB, polychlorinated biphenyl; PCB-77, 3,3′,4,4′-tetrachlorobiphenyl; PGE₂, prostaglandin E₂; PKC, protein kinase C; PMA, phorbol myristate acetate; PMC, 2,2,5,7,8-pentamethyl-6-hydroxychromane; PPAR, peroxisome proliferator-activated receptor; PP2A, protein phosphatase 2A; TNF-α, tumor necrosis factor-α; TRAIL, TNF-related apoptosis-inducing ligand; Trolox, 6-hydroxyl-2,5,7,8-tetramethylchroman-2-carboxylic acid; VLDL, very low density lipoprotein. is a eukaryotic transcription factor that may be activated by oxidative stress. Because of this hypothesis, the effect of vitamin E on NF-κB activation has been examined in many studies, using both in vivo and in vitro models. Most of these studies have observed that vitamin E inhibits the activation of NF-κB, with the greatest inhibition seen with the succinate form. Vitamin E may be inhibiting NF-κB by reducing oxidative stress or through one of its nonantioxidant functions; this is not clear at the present time. It also is not known if the inhibition of NF-κB is necessary for any of vitamin E's effects on gene expression and the resulting physiological effects.