title: [Activation of sterol regulatory element binding protein and its involvement in endothelial cell migration].
abstract: OBJECTIVE
  To study the activation of sterol regulatory element binding protein (SREBP) and its critical role in endothelial cell migration.
  
  
  METHODS
  Bovine aortic endothelial cells (ECs) were cultured. The expression of SREBP and Cdc42 were determined by Western blot and quantitative real-time PCR. Moreover, outward growth migration model and transwell chamber assay were used to detect ECs migration.
  
  
  RESULTS
  (1) SREBP was activated during ECs migration. Western blot analysis demonstrated increased active form SREBP in migrating as compared to non-migrating ECs population. SREBP activation decreased as ECs migration slowed;(2) Coincidental with SREBP activation, mRNA expression of its target genes such as low density lipoprotein receptor, HMG-CoA reductase, and fatty acid synthase also increased in migrating ECs population as detected by real-time PCR; (3) Migration induced SREBP activation in ECs was inhibited by SREBP-acting protein RNAi and pharmacologically by 25-hydroxycholesterol; (4) Inhibition of SREBP led to decreased ECs migration in various models; (5) Cells genetically deficient in SREBP-acting protein, S1P, or S2P, phenotypically exhibited impaired migration; (6) SREBP inhibition in ECs suppressed the activity of small GTPase Cdc42, a key molecule for ECs motility.
  
  
  CONCLUSIONS
  SREBP is activated during and plays a critical role in ECs migration. Targeting SREBP could become a novel approach in fighting diseases involving abnormal ECs migration.
authors.affiliation: Department of Geriatrics, Qilu Hospital of Shandong University, Jinan 250012, China.
authors.forename: Ya-bing
authors.initials: YB
authors.lastname: Ma
authors.forename: Bao-ying
authors.initials: BY
authors.lastname: Li
authors.forename: Hai-qing
authors.initials: HQ
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Yao
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Koch
authors.forename: Andrea D
authors.initials: AD
authors.lastname: Eckhart
authors.forename: Rui-hai
authors.initials: RH
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology; D016466:CHO Cells; D002417:Cattle; D002465:Cell Movement; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D042783:Endothelial Cells; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism*; D006888:Hydroxycholesterols / Q000494:pharmacology; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D011973:Receptors, LDL / Q000235:genetics / Q000378:metabolism*; D051779:Sterol Regulatory Element Binding Proteins / Q000378:metabolism* / Q000502:physiology
chemical_list: D006888:Hydroxycholesterols; D012333:RNA, Messenger; D011973:Receptors, LDL; D051779:Sterol Regulatory Element Binding Proteins; C007997:25-hydroxycholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D064429:Fatty Acid Synthases