title: Identification of plasma APE1/Ref-1 in lipopolysaccharide-induced endotoxemic rats: implication of serological biomarker for an endotoxemia.
abstract: Apurinic/apyrimidinic endonuclease1/Redox factor-1 (APE1/Ref-1) is a multifunctional protein involved in base excision DNA repair and in transcriptional regulation of gene expression. We investigated whether APE1/Ref-1 increased in plasma of endotoxemic rats. Lipopolysaccharide (LPS) was used to induce endotoxemia in rats. Administration of LPS (10 mg/kg, i.p.) significantly induced plasma nitrite production and tumor necrosis factor-α (TNF-α). A 37 kDa immunoreactive band was detected in cell-free plasma of LPS-treated rats using anti-APE1/Ref-1, which reached a maximum at 12 h after the LPS injection. The 37 kDa immunoreactive band was identified as rat APE1/Ref-1 by liquid chromatography/tandem mass spectrometry. Interestingly, treatment with recombinant human APE1/Ref-1 protein (2-5 μg/ml for 18 h) inhibited TNF-α-induced vascular cell adhesion molecule-1 expression in human umbilical vein endothelial cells. Taken together, the level of plasma APE1/Ref-1 increased in LPS-induced endotoxemic rats, suggesting that plasma APE1/Ref-1 might serve as a serological biomarker for endotoxemia.
authors.affiliation: Department of Physiology, School of Medicine, Chungnam National University, Daejeon 301-747, Republic of Korea.
authors.forename: Myoung Soo
authors.initials: MS
authors.lastname: Park
authors.forename: Yu Ran
authors.initials: YR
authors.lastname: Lee
authors.forename: Sunga
authors.initials: S
authors.lastname: Choi
authors.forename: Hee Kyoung
authors.initials: HK
authors.lastname: Joo
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Cho
authors.forename: Cuk Seong
authors.initials: CS
authors.lastname: Kim
authors.forename: Jin Bong
authors.initials: JB
authors.lastname: Park
authors.forename: Eun-Kyeong
authors.initials: EK
authors.lastname: Jo
authors.forename: Byeong Hwa
authors.initials: BH
authors.lastname: Jeon
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000097:blood*; D019446:Endotoxemia / Q000097:blood* / Q000139:chemically induced / Q000175:diagnosis; D008070:Lipopolysaccharides; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D015415:Biomarkers; D008070:Lipopolysaccharides; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase