Overexpression of Truncated IκBα Induces TNF-α–Dependent Apoptosis in Human Vascular Smooth Muscle Cells

Abstract
—Dysregulation of apoptosis is one of the likely underlying mechanisms of neointimal thickening, a disorder in which proinflammatory cytokines may influence the function of vascular smooth muscle cells (VSMCs) and contribute to atherogenesis. One of these cytokines, tumor necrosis factor-α (TNF-α), induces 2 possibly conflicting pathways, 1 leading to the activation of nuclear factor-κB (NF-κB) and the other leading to caspase-mediated apoptosis. We investigated whether specific inhibition of NF-κB affects TNF-α–dependent apoptosis in human VSMCs. To inhibit NF-κB activation specifically, we constructed a recombinant adenovirus vector expressing a truncated form of the inhibitor protein IκBα (AdexIκBΔN) that lacks the phosphorylation sites essential for activation of NF-κB. The IκBΔN was overexpressed by adenoviral infection and was resistant to stimulus-dependent degradation. Electromobility gel shift and luciferase assays demonstrated that overexpression of IκBΔN inhibited NF-κB activation induc...

This publication has 26 references indexed in Scilit: