title: Novel role of NF-κB-p65 in antioxidant homeostasis in human kidney-2 cells.
abstract: Nuclear factor-κB (NF-κB) plays a role in inflammation. However, we recently reported an association between NF-κB and antioxidant enzymes in renal proximal tubules of exercise-trained rats, suggesting its role in antioxidant homeostasis (George L, Lokhandwala MF, Asghar M. Am J Physiol Renal Physiol 297: F1174-F1180, 2009). A direct role of NF-κB in antioxidant homeostasis in renal cells has not been elucidated and warrants investigation. Therefore, we examined whether NF-κB has a direct role in antioxidant homeostasis and redox balance in human kidney-2 cells overexpressing NF-κB-p65 and compared them with the cells overexpressing Nrf-2, a well-known transcription factor involved in antioxidant homeostasis. The ability of NF-κB-p65 to increase antioxidant enzymes, to reduce reactive oxygen species (ROS), and to rescue ROS-induced renal dopamine D1 receptor dysfunction, was studied. The transcription activity of NF-κB-p65 and Nrf-2, measured as luciferase reporter activity, increased in cells overexpressing these nuclear factors. The levels of mRNA and activity of glutathione peroxidase as well as the protein levels of superoxide dismutase-1 and glutamylcystein transferase were increased in cells overexpressing NF-κB-p65 and Nrf-2. Furthermore, the levels of ROS decreased and D1 receptor agonist SKF38393-mediated [(35)S]GTPγS binding (index of D1 receptor function) increased in the presence of hydrogen peroxide in cells overexpressing NF-κB-p65 and Nrf-2. These results suggest a direct role of NF-κB-p65 in antioxidant homeostasis, contributing to redox balance in renal cells.
authors.affiliation: Heart and Kidney Institute, College of Pharmacy, University of Houston, TX 77204, USA.
authors.forename: Liza E
authors.initials: LE
authors.lastname: George
authors.forename: Mustafa F
authors.initials: MF
authors.lastname: Lokhandwala
authors.forename: Mohammad
authors.initials: M
authors.lastname: Asghar
mesh_terms: D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000975:Antioxidants / Q000378:metabolism*; D015153:Blotting, Western; D002460:Cell Line; D018491:Dopamine Agonists / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D005822:Genetic Vectors; D005979:Glutathione Peroxidase / Q000096:biosynthesis / Q000378:metabolism; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D051267:NF-E2-Related Factor 2 / Q000096:biosynthesis / Q000235:genetics; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D051996:Transcription Factor RelA / Q000235:genetics / Q000502:physiology*; D014162:Transfection
chemical_list: D000975:Antioxidants; D018491:Dopamine Agonists; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D017382:Reactive Oxygen Species; D051996:Transcription Factor RelA; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D005979:Glutathione Peroxidase