Up-regulation of Nrf2-antioxidant signaling by Açaí (Euterpe oleracea Mart.) extract prevents oxidative stress in human endothelial cells

Abstract

The current study evaluated the content and profile of phenolic compounds, the in vitro antioxidant activity, and the role of the Nrf2-signaling pathway in the cellular antioxidant activity of açaí seed extract (ASE) in H2O2-induced oxidative stress in human endothelial cells (HUVEC). Seven phenolic compounds were quantified in ASE by HPLC-DAD-MS, among which (−)-epicatechin and (+)-catechin were the most abundant. ASE exhibited a potent in vitro antioxidant activity evaluated by different assays. In HUVEC, ASE decreased H2O2-induced cytotoxicity, prevented migratory capacity loss and oxidative stress. ASE promoted up-regulation of the master antioxidant transcription factor Nrf2 through activation of ERK, thus leading to an increased expression of antioxidant enzymes. Our results demonstrated that ASE, rich in phenolic compounds, reversed H2O2-induced oxidative stress and that this effect was partially attributed to positive modulation of Nrf2 signaling pathway in HUVEC.

Keywords

• Polyphenols
• HPLC-DAD-MS
• HUVEC
• FRAP
• TEAC
• Folin-Ciocalteu