title: Glucose transporter member 1 is involved in UVB-induced epidermal hyperplasia by enhancing proliferation in epidermal keratinocytes.
abstract: BACKGROUND
  Glucose transporter member 1 (GLUT-1) is one of the major facilitated glucose transporters and contributes to the promotion of keratinocyte proliferation in psoriasis and carcinogenic lesions. In this study, we postulate that GLUT-1 is involved in ultraviolet B (UVB)-induced epidermal hyperplasia. The purpose of this study is to investigate the possible role of GLUT-1 in UVB-induced hyperplasia.
  
  
  METHODS
  The effects of UVB on GLUT-1 expression levels were investigated in in vitro and in vivo studies. In addition, the involvement of epidermal growth factor (EGF) and hypoxia inducible factor-1 alpha (HIF-1α), transcriptional factors for GLUT-1, in GLUT-1-related events were investigated.
  
  
  RESULTS
  GLUT-1 mRNA and its protein levels were markedly increased by UVB irradiation in HaCaT cells. In in vivo studies, a strong immunofluorescence signal of GLUT-1 was clearly observed around the basal layer of the epidermis, which proliferated excessively by UVB irradiation. In HaCaT cells, EGF mRNA and its protein levels were markedly increased by UVB irradiation, and then the GLUT-1 mRNA level was significantly increased by treatment with EGF. Additionally, the upregulation of GLUT-1 by both UVB irradiation and treatment with EGF was significantly suppressed by transfection with HIF-1α siRNA.
  
  
  CONCLUSIONS
  We conclude that GLUT-1 is involved in UVB-induced epidermal hyperplasia by enhancing proliferation of epidermal basal cells, and the GLUT-1-related event might be regulated by an increase in HIF-1α stimulated by EGF.
authors: Research Laboratories, Nippon Menard Cosmetic, Nagoya, Japan.
authors: Takumi
authors: T
authors: Tochio
authors: Hiroshi
authors: H
authors: Tanaka
authors: Satoru
authors: S
authors: Nakata
mesh_terms: D000818:Animals; D015153:Blotting, Western; D049109:Cell Proliferation / Q000528:radiation effects*; D004797:Enzyme-Linked Immunosorbent Assay; D004815:Epidermal Growth Factor / Q000378:metabolism; D004817:Epidermis / Q000378:metabolism* / Q000473:pathology*; D019084:Fluorescent Antibody Technique, Indirect; D051272:Glucose Transporter Type 1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D006965:Hyperplasia; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism; D015603:Keratinocytes / Q000378:metabolism / Q000473:pathology*; D008297:Male; D051379:Mice; D023421:Models, Animal; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014162:Transfection; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D051272:Glucose Transporter Type 1; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D004815:Epidermal Growth Factor