Fig. 4

Oxidative stress increases LOX-1 expression at the cellular plasma membrane through the activation of NF-κB. Ox-HDL-induced NOX isoform mRNA expression was determined by RT-qPCR in HAEC (a) and HUVEC (b). Data are expressed normalized to HDL condition (N = 3). Statistical differences for HAEC and HUVEC samples were assessed by a one-way analysis of variance (ANOVA) (Kruskal–Wallis) followed by Dunn’s post hoc test. *P < 0.05. **P < 0.01. Graph bars show the mean ± SD. HAEC and HUVEC were exposed to H₂O₂ (0, 1, 10, 100 μM) (c and d) and GSSG (0, 0.02, 0.2, 2 mM) (e and f) for 24 h, and LOX-1 expression was analyzed. Data are expressed normalized to 0 μM H₂O₂ or GSSG (N = 5). Statistical differences were assessed by a one-way analysis of variance (ANOVA) (Kruskal–Wallis) followed by Dunn’s post hoc test. *P < 0.05, **P < 0.01. Graph bars show the mean ± SD. LOX-1 expression was measured in cytosol-rich and membrane-rich fractions from cells exposed to H₂O₂ (100 μM) (g–i) and GSSG (2 mM) (h–j) for 24 h. Protein levels were normalized against Na⁺ pump in the membrane-rich fraction. Data are expressed normalized to vehicle condition in the absence of stimuli (N = 4). LOX-1 expression was measured in the plasma membrane-rich fraction from ECs exposed to H₂O₂ (100 μM) and GSSG (2 mM) for 24 h in the absence (–) or presence (+) of the LOX-1 inhibitor κ-carrageenan (250 μg/ml) (k, l), the NF-κB inhibitor SC3060 (5 μM) (m, n), H₂O₂ (100  μM) (o, p) and GSSG (2 mM) (q, r). Data are expressed normalized to vehicle condition in the absence of stimuli (N = 4). Statistical differences were assessed by a two-way analysis of variance (ANOVA) followed by Tukey post hoc test. **P < 0.01. Graph bars show the mean ± SD