Generation of stable ARE- driven reporter system for monitoring oxidative stress

Abstract

Background: NF-E2-related factor2 (Nrf2)-antioxidant response element (ARE) signaling pathway is the major defensive mechanism against oxidative stress and is up regulated by specific antioxidants and oxidants to comprise the chemoptotective response. Detection of ARE-activating compounds helps to develop new drugs and identify/quantify the tension range of the oxidants. Important reasons promoting this work are high throughput, rapid and inexpensive experiments relative to the in vitro studies for ARE-Nrf2 pathway monitoring of chemicals and environmental samples. Methods: In this study hepatoma Huh7 reporter cell line was generated which contains a luciferase gene under the control of an ARE. This is the first example of ARE construct containing one copy of extended consensus response element. The cells were treated with hydroquinone (HQ) and p-benzoquinone (BQ) (oxidative stress inducers) and the antioxidant, curcumin. Results: The luciferase activity was induced in a concentration-dependent manner in a concentration range of 1-2 μM for BQ and HQ. Curcumin was also validated as an ARE inducer in concentration above 10 μM. In addition, this reporter cell line provides a rapid detection as early as 4 h to respond to the ARE inducers. Conclusion: It is a powerful tool for the sensitive and selective screening of chemicals, drugs and environmental samples for their antioxidant and oxidant activities.