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Lysophosphatidylcholine induces oxidative stress in human endothelial cells via NOX5 activation - implications in atherosclerosis.

Authors :
da Silva JF
Alves JV
Silva-Neto JA
Costa RM
Neves KB
Alves-Lopes R
Carmargo LL
Rios FJ
Montezano AC
Touyz RM
Tostes RC
Source :
Clinical science (London, England : 1979) [Clin Sci (Lond)] 2021 Aug 13; Vol. 135 (15), pp. 1845-1858.
Publication Year :
2021

Abstract

Objective: The mechanisms involved in NOX5 activation in atherosclerotic processes are not completely understood. The present study tested the hypothesis that lysophosphatidylcholine (LPC), a proatherogenic component of oxLDL, induces endothelial calcium influx, which drives NOX5-dependent reactive oxygen species (ROS) production, oxidative stress, and endothelial cell dysfunction.<br />Approach: Human aortic endothelial cells (HAEC) were stimulated with LPC (10-5 M, for different time points). Pharmacological inhibition of NOX5 (Melittin, 10-7 M) and NOX5 gene silencing (siRNA) was used to determine the role of NOX5-dependent ROS production in endothelial oxidative stress induced by LPC. ROS production was determined by lucigenin assay and electron paramagnetic spectroscopy (EPR), calcium transients by Fluo4 fluorimetry, and NOX5 activity and protein expression by pharmacological assays and immunoblotting, respectively.<br />Results: LPC increased ROS generation in endothelial cells at short (15 min) and long (4 h) stimulation times. LPC-induced ROS was abolished by a selective NOX5 inhibitor and by NOX5 siRNA. NOX1/4 dual inhibition and selective NOX1 inhibition only decreased ROS generation at 4 h. LPC increased HAEC intracellular calcium, important for NOX5 activation, and this was blocked by nifedipine and thapsigargin. Bapta-AM, selective Ca2+ chelator, prevented LPC-induced ROS production. NOX5 knockdown decreased LPC-induced ICAM-1 mRNA expression and monocyte adhesion to endothelial cells.<br />Conclusion: These results suggest that NOX5, by mechanisms linked to increased intracellular calcium, is key to early LPC-induced endothelial oxidative stress and pro-inflammatory processes. Since these are essential events in the formation and progression of atherosclerotic lesions, the present study highlights an important role for NOX5 in atherosclerosis.<br /> (© 2021 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

Details

Language :
English
ISSN :
1470-8736
Volume :
135
Issue :
15
Database :
MEDLINE
Journal :
Clinical science (London, England : 1979)
Publication Type :
Academic Journal
Accession number :
34269800
Full Text :
https://doi.org/10.1042/CS20210468