4-Hydroxynonenal Contributes to Angiogenesis through a Redox-Dependent Sphingolipid Pathway: Prevention by Hydralazine Derivatives

Figure 3

Implication of ROS in tube formation by 4-HNE. (a) Time-course of intracellular ROS production evoked by 4-HNE (0.5 µM) in HMEC-1 and measured fluorometrically using the H2DCFDA probe (5 µM final concentration). Results are expressed as % of the unstimulated control. (b) Effect of the antioxidant trolox (10 µM) and of NADPH oxidase inhibitors DPI and Vas2870 (10 µM each) and of the anti-Lox-1 antibody (5 µg/ml) on ROS generated by HMEC-1 after 30 min of contact with 4-HNE (0.5 µM). (c) Effect of trolox, DPI, and Vas2870 and anti-Lox-1 antibody, on tube formation elicited by 4-HNE (0.5 µM). Representative pictures of tube formation in the presence of 4-HNE (0.5 µM) and without (none) or with inhibitors Vas2870 (Vas) or anti-Lox-1 Ab (aLox1). (d) Effect of the anti-Lox-1 Ab on tube formation elicited by oxLDL (20 µg/ml). Note that the anti-Lox-1 Ab has no effect on tubes formed by 4-HNE-stimulated HMEC-1 but inhibits tubes formed by oxLDL-stimulated cells. These data are means ± SEM of 5 separate experiments. ; ns: not significant.

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