Redox-sensitive vascular smooth muscle cell proliferation is mediated by GKLF and Id3 in vitro and in vivo.
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.
Nickenig
Georg
G
Universitätskliniken des Saarlandes, Medizinische Klinik und Poliklinik, Innere Medizin III, 66424 Homburg/Saar, Germany. nickenig@med-in.uni-sb.de
Baudler
Stephanie
S
Müller
Cornelius
C
Werner
Christian
C
Werner
Nikos
N
Welzel
Hilke
H
Strehlow
Kerstin
K
Böhm
Michael
M
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
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