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En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Docosahexaenoic acid down-regulates endothelial Nox 4 through a sPLA2 signalling pathway
Doriane Richard1, Claude Wolf, Ullah Barbe
1Laboratory of Micronutrients and Cardiovascular Disease, Université Pierre et Marie Curie, Paris 6, France.
Biochemical and Biophysical Research Communications
|September 10, 2009
Summary
Docosahexaenoic acid (DHA) reduces vascular inflammation by decreasing phospholipase A2 (sPLA2) and NADPH oxidase 4 (Nox4) activity. This antioxidant effect involves sPLA2-mediated down-regulation of Nox4 via ERK and PKC signaling pathways.
Area of Science:
- Biochemistry
- Molecular Biology
- Cardiovascular Research
Background:
- Vascular inflammation involves key enzymes like phospholipase A2 (sPLA2) and NADPH oxidase 4 (Nox4).
- Docosahexaenoic acid (DHA) is an omega-3 fatty acid with potential anti-inflammatory properties.
Purpose of the Study:
- To investigate the anti-inflammatory and antioxidant effects of DHA.
- To evaluate DHA's modulation of sPLA2 and Nox4 in human aortic endothelial cells (HAECs).
Main Methods:
- HAECs were exposed to DHA and stimulated with A23187, Ang II, and IL-1beta.
- DHA incorporation into phospholipids was analyzed.
- Expression and activity of sPLA2 and Nox4 were measured.
- The role of sPLA2 in DHA's effects on Nox4 was assessed using specific inhibitors.
- ERK and PKC signaling pathways were investigated.
Main Results:
- DHA was preferentially incorporated into HAEC outer leaflet phospholipids.
- DHA pre-treatment inhibited HAEC stimulation by A23187 and Ang II.
- DHA modulated Group V sPLA2 RNA expression.
- DHA decreased Nox4 expression and activity, reducing reactive oxygen species production.
- Group V sPLA2 was found to mediate the down-regulation of Nox4 by DHA through ERK and PKC.
Conclusions:
- DHA exhibits anti-inflammatory and antioxidant properties in HAECs.
- DHA's effects are partly mediated by the interplay between Group V sPLA2 and Nox4.
- This interaction is regulated by ERK and PKC signaling pathways, highlighting a novel mechanism for DHA's vascular benefits.
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