title: Dihydrotestosterone induces SREBP-1 expression and lipogenesis through the phosphoinositide 3-kinase/Akt pathway in HaCaT cells.
abstract: BACKGROUND
  The purpose of this study was to investigate the effects and mechanisms of dihydrotestosterone (DHT)-induced expression of sterol regulatory element binding protein-1 (SREBP-1), and the synthesis and secretion of lipids, in HaCaT cells. HaCaT cells were treated with DHT and either the phosphoinositide 3-kinase inhibitor LY294002 or the extracellular-signal-regulated kinase (ERK) inhibitor PD98059. Real time-PCR, Western blot, Oil Red staining and flow cytometry were employed to examine the mRNA and protein expressions of SREBP-1, the gene transcription of lipid synthesis, and lipid secretion in HaCaT cells.
  
  
  RESULTS
  We found that DHT upregulated mRNA and protein expressions of SREBP-1. DHT also significantly upregulated the transcription of lipid synthesis-related genes and increased lipid secretion, which can be inhibited by the addition of LY294002.
  
  
  CONCLUSIONS
  Collectively, these results indicate that DHT induces SREBP-1 expression and lipogenesis in HaCaT cells via activation of the phosphoinositide 3-kinase/Akt Pathway.
authors.affiliation: Department of Dermatology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
authors.forename: Bing-rong
authors.initials: BR
authors.lastname: Zhou
authors.forename: Qiu-hong
authors.initials: QH
authors.lastname: Huang
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.forename: Zhi-qiang
authors.initials: ZQ
authors.lastname: Yin
authors.forename: Dan
authors.initials: D
authors.lastname: Luo
mesh_terms: D002460:Cell Line; D013196:Dihydrotestosterone / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D050155:Lipogenesis / Q000187:drug effects*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics* / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; C497387:SREBF1 protein, human; D051780:Sterol Regulatory Element Binding Protein 1; D013196:Dihydrotestosterone; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt