title: Oxidative stress induced lipocalin 2 gene expression: addressing its expression under the harmful conditions.
abstract: Lipocalin 2 (Lcn2, NGAL) is a member of the lipocalin superfamily with diverse functions such as the transport of fatty acids and the induction of apoptosis. Previous reports indicated that expression of Lcn2 is induced under harmful conditions. However, the mechanisms of the induction of Lcn2 expression remain to be elucidated. In this report, we intended to identify the factor or factors that induce Lcn2 expression. Up-regulation of Lcn2 expression after X-ray exposure was detected in the heart, the kidney and especially in the liver. Primary culture of liver component cells revealed that this up-regulation in the liver was induced in hepatocytes. Up-regulation of Lcn2 expression was also detected in HepG2 cells after the administration of X-rays or H(2)O(2). Interestingly, up-regulation of Lcn2 expression after H(2)O(2) treatment was canceled by the addition of the anti-oxidants, dimethylsulfoxide or cysteamine. These results strongly suggest that Lcn2 expression is induced by reactive oxygen species. Therefore, Lcn2 could be a useful biomarker to identify oxidative stress both in vitro and in vivo.
authors.affiliation: Department of Pathology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
authors.forename: Mehryar Habibi
authors.initials: MH
authors.lastname: Roudkenar
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kuwahara
authors.forename: Taisuke
authors.initials: T
authors.lastname: Baba
authors.forename: Amaneh Mohammadi
authors.initials: AM
authors.lastname: Roushandeh
authors.forename: Shigeko
authors.initials: S
authors.lastname: Ebishima
authors.forename: Shinya
authors.initials: S
authors.lastname: Abe
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Ohkubo
authors.forename: Manabu
authors.initials: M
authors.lastname: Fukumoto
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism*; D000818:Animals; D004307:Dose-Response Relationship, Radiation; D015870:Gene Expression / Q000502:physiology* / Q000528:radiation effects*; D022781:Hepatocytes / Q000378:metabolism* / Q000528:radiation effects*; D000071068:Lipocalin-2; D054834:Lipocalins; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D015513:Oncogene Proteins / Q000378:metabolism*; D009928:Organ Specificity; D018384:Oxidative Stress / Q000502:physiology* / Q000528:radiation effects*; D011829:Radiation Dosage; D014018:Tissue Distribution
chemical_list: D000209:Acute-Phase Proteins; D000071068:Lipocalin-2; D054834:Lipocalins; D015513:Oncogene Proteins; C071332:Lcn2 protein, mouse