Proteasome inhibition induces ROS production and disrupts ER stress-induced NADPH oxidase up-regulation.

<p>(A) ROS production in VSMC incubated for 4 h with Tn (5 µg/mL) or/and MG132 (1 µM), assessed through HPLC analysis of DHE oxidation products (50 µM, 30 min incubation), as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0014591#s4" target="_blank">Methods</a>. Results depict levels of 2-hydroxyethidium (EOH) or ethidium (E) products. (B) NADPH oxidase activity measured in membrane-enriched homogenates from VSMC incubated for 4 h with Tn or MG132. Activity was measured with DHE technique, analogous to (A), as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0014591#s4" target="_blank">Methods</a>. Data are mean ± SD of 3 independent experiments.*P<0.05 vs. Control. #P<0.05 vs.Tn.