PT  - JOURNAL ARTICLE
AU  - Zhongzhen Nie
AU  - Yun Mei
AU  - Mary Ford
AU  - Leonard Rybak
AU  - Adrianna Marcuzzi
AU  - Hongzu Ren
AU  - Gary L. Stiles
AU  - Vickram Ramkumar
TI  - Oxidative Stress Increases A<sub>1</sub> Adenosine Receptor Expression by Activating Nuclear Factor κB
AID  - 10.1124/mol.53.4.663
DP  - 1998 Apr 01
TA  - Molecular Pharmacology
PG  - 663--669
VI  - 53
IP  - 4
4099  - http://molpharm.aspetjournals.org/content/53/4/663.short
4100  - http://molpharm.aspetjournals.org/content/53/4/663.full
SO  - Mol Pharmacol1998 Apr 01; 53
AB  - The A1 adenosine receptor (A1AR) contributes to the cytoprotective action of adenosine under conditions known to generate reactive oxygen species (ROS). Pharmacological manipulation of A1AR expression has been shown to modulate this cytoprotective role. In this study, we provide evidence that ROS generated could increase the expression of the A1AR and thereby offset the detrimental effects of ROS. Incubation of DDT1MF-2 smooth muscle cells with ROS-generating chemotherapeutic agents, such as cisplatin (2.5 μm) or H2O2 (10 μm), elicited an increase in A1AR expression within 24 hr. The induction by H2O2 was reduced by the ROS scavenger catalase but not superoxide dismutase. Inhibition of nuclear factor κB (NFκB) by pyrrolidine dithiocarbamate (200 μm), dexamethasone (100 nm), or genistein (1 μm) abrogated the cisplatin-mediated increase in A1AR. Cisplatin promoted rapid translocation of NFκB (but not AP-1) to the nucleus, as detected by electrophoretic mobility shift assays and by Western blotting. A putative NFκB sequence in the A1AR promoter effectively competed with labeled κB probe for binding in nuclear preparations derived from DDT1MF-2 cells. Transient transfection of DDT1MF-2 cells with the A1AR promoter coupled to firefly luciferase reporter gene led to cisplatin-inducible and pyrrolidine dithiocarbamate-sensitive luciferase activity, suggesting the presence of functional NFκB binding site(s) in the A1AR promoter sequence. Treatment of cells with (R)-phenylisopropyladenosine (1 μm), an agonist of the A1AR, reduced cisplatin-mediated lipid peroxidation, which was reversed after blockade of the A1AR. These data suggest that ROS can increase the expression of the A1AR by activating NFκB regulatory site(s) on this gene and thereby enhance the cytoprotective role of adenosine.