title: Aspirin-induced blockade of NF-kappaB activity restrains up-regulation of glial fibrillary acidic protein in human astroglial cells.
abstract: The marked induction of glial fibrillary acidic protein (GFAP) has been observed in astrocytes during neuropathological processes accompanying reactive gliosis; however, the precise molecular mechanism(s) underlying this GFAP induction remains poorly resolved. Therefore, in this study, we examined whether the change of nuclear factor-kappa B (NF-kappaB) activity can influence GFAP expression levels. Aspirin, widely used to prevent NF-kappaB activity, reduced the levels of GFAP mRNA and protein in human astroglial cells including human glioblastoma A172 cells and primary human brain astrocyte cells (HBAs). Furthermore, aspirin inhibited the effects of hypoxic injury on the up-regulation of GFAP expression in HBAs. We confirmed the repressive effect of aspirin on GFAP transcription by GFAP promoter-driven reporter assay and found that one NF-kappaB binding site conserved in the mouse and human GFAP gene promoters is critical for this effect. To further delineate whether NF-kappaB is directly involved in the regulation of GFAP gene expression, we transfected A172 cells with an expression vector encoding a super-repressor IkappaBalpha protein (IkappaBalpha-SR) to specifically inhibit NF-kappaB activity and found the marked reduction of GFAP protein levels in IkappaBalpha-SR-transfectant cells. Taken together, our results suggest that NF-kappaB may play pivotal roles in GFAP gene expression.
authors.affiliation: Department of Oral Physiology, College of Dentistry, Pusan National University, Busan 602-739, South Korea.
authors.forename: Moon-Kyoung
authors.initials: MK
authors.lastname: Bae
authors.forename: Su-Ryun
authors.initials: SR
authors.lastname: Kim
authors.forename: Hak-Joong
authors.initials: HJ
authors.lastname: Lee
authors.forename: Hee-Jun
authors.initials: HJ
authors.lastname: Wee
authors.forename: Mi-Ae
authors.initials: MA
authors.lastname: Yoo
authors.forename: Sae
authors.initials: S
authors.lastname: Ock Oh
authors.forename: Sun-Yong
authors.initials: SY
authors.lastname: Baek
authors.forename: Bong-Seon
authors.initials: BS
authors.lastname: Kim
authors.forename: Jae-Bong
authors.initials: JB
authors.lastname: Kim
authors.lastname: Sik-Yoon
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Bae
mesh_terms: D001241:Aspirin / Q000494:pharmacology*; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D015687:Cell Hypoxia / Q000187:drug effects; D015536:Down-Regulation / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D051550:I-kappa B Kinase / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects*
chemical_list: D005904:Glial Fibrillary Acidic Protein; D016328:NF-kappa B; D012333:RNA, Messenger; D051550:I-kappa B Kinase; D001241:Aspirin