title: Redox-sensitive vascular smooth muscle cell proliferation is mediated by GKLF and Id3 in vitro and in vivo.
abstract: Reactive oxygen species such as superoxide and hydroxyl radicals have been implicated in the pathogenic growth of various cell types. The molecular mechanisms involved in redox-sensitive cell growth control are poorly understood. Stimulation of cultured vascular smooth muscle cells (VSMC) with xanthin/xanthin oxidase (X/XO) increases proliferation, whereas stimulation with hydrogen peroxide and Fe3+NTA (H-Fe) causes growth arrest of VSMC. Differential Display led to the identification of two novel, differentially regulated redox-sensitive genes. The dominant negative helix-loop-helix protein Id3 is induced by X/XO and down-regulated by H-Fe. The transcription factor gut-enriched Kruppel-like factor (GKLF) is induced by H-Fe but not by X/XO. Induction of GKLF and inhibition of Id3 via transfection experiments leads to growth arrest, whereas overexpression of Id3 and inhibition of GKLF cause cell growth. Id3 down-regulation is induced via binding of GKLF to the Id3 promotor and concomitantly reduced Id3 gene transcription rate. GKLF induction by H-Fe is mediated through hydroxyl radicals, p38MAP kinase-, calcium-, and protein synthesis-dependent pathways. Id3 is induced by X/XO via superoxide, calcium, p38, and p42/44 MAP kinase. GKLF induces and Id3 depresses expression of p21WAF1/Cip1, p27KIP1, p53. Induction of Id3 is accomplished by angiotensin II via superoxide release. A vascular injury mouse model revealed that Id3 is overexpressed in proliferating vascular tissue in vivo. These findings reveal novel mechanisms of redox-controlled cellular proliferation involving GKLF and Id3 that may have general implications for our understanding of vascular and nonvascular growth control.
authors.affiliation: Universitätskliniken des Saarlandes, Medizinische Klinik und Poliklinik, Innere Medizin III, 66424 Homburg/Saar, Germany. nickenig@med-in.uni-sb.de
authors.forename: Georg
authors.initials: G
authors.lastname: Nickenig
authors.forename: Stephanie
authors.initials: S
authors.lastname: Baudler
authors.forename: Cornelius
authors.initials: C
authors.lastname: Müller
authors.forename: Christian
authors.initials: C
authors.lastname: Werner
authors.forename: Nikos
authors.initials: N
authors.lastname: Werner
authors.forename: Hilke
authors.initials: H
authors.lastname: Welzel
authors.forename: Kerstin
authors.initials: K
authors.lastname: Strehlow
authors.forename: Michael
authors.initials: M
authors.lastname: Böhm
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D016893:Carotid Stenosis / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D006131:Growth Inhibitors / Q000235:genetics / Q000502:physiology*; D051796:Inhibitor of Differentiation Proteins; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D009363:Neoplasm Proteins; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015290:Second Messenger Systems; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic; D019820:Xanthine / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000494:pharmacology
chemical_list: D004268:DNA-Binding Proteins; D006131:Growth Inhibitors; D051796:Inhibitor of Differentiation Proteins; C000715467:KLF4 protein, human; C000715468:Klf4 protein, mouse; C000715469:Klf4 protein, rat; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D014157:Transcription Factors; D000804:Angiotensin II; C075640:ID3 protein, human; D019820:Xanthine; D014969:Xanthine Oxidase