title: Effects of SOCS 1/3 gene silencing on the expression of C/EBPα and PPARγ during differentiation and maturation of rat preadipocytes.
abstract: BACKGROUND
  Suppressor of cytokine signaling-1 and -3 (SOCS-1 and SOCS-3) are two important negative regulators in the insulin-signaling pathway, and their overexpression may aggravate insulin resistance. Subjects with insulin resistance are often obese and have increased expressions of SOCS-1 and SOCS-3. We speculated that SOCS-1 and SOCS-3 may be involved in abnormal deposition of adipose tissues during insulin resistance.
  
  
  METHODS
  A catch-up growth intrauterine growth retardation (CG-IUGR) rat model with insulin resistance was established; mRNA and protein expression of SOCS-1, SOCS-3, the CCAAT/enhancer binding protein (C/EBPα), and peroxisome proliferator-activated receptor (PPARγ) in adipose tissue were measured by real-time PCR and western blot; plasmids carrying small hairpin RNAs (shRNAs) targeting the SOCS-1 and SOCS-3 genes were constructed and transfected into preadipocytes, which were then induced to mature. At 72 h after differentiation was induced, the expressions of C/EBPα and PPARγ, two important molecules promoting the differentiation of preadipocytes, were detected.
  
  
  RESULTS
  Expressions of SOCS-1, SOCS-3, C/EBPα, and PPARγ were markedly increased in adipose tissues of CG-IUGR rats, whereas the expressions of C/EBPα and PPARγ were significantly reduced after gene silencing of SOCS-1 or SOCS-3 in adipocytes.
  
  
  CONCLUSIONS
  Overexpression of SOCS-1 and SOCS-3 may enhance the expression of C/EBPα and PPARγ, resulting in abnormal deposition of adipose tissues during insulin resistance.
authors.affiliation: Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Rui-Dan
authors.initials: RD
authors.lastname: Zheng
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Liao
authors.forename: Juan
authors.initials: J
authors.lastname: Ye
authors.forename: Cheng-Bin
authors.initials: CB
authors.lastname: Wang
authors.forename: Jin-Zhi
authors.initials: JZ
authors.lastname: Gao
authors.forename: Yan-Qin
authors.initials: YQ
authors.lastname: Ying
authors.forename: Qin
authors.initials: Q
authors.lastname: Ning
authors.forename: Xiao-Ping
authors.initials: XP
authors.lastname: Luo
mesh_terms: D017667:Adipocytes / Q000502:physiology*; D000818:Animals; D015153:Blotting, Western; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D048708:Cell Growth Processes / Q000502:physiology; D017931:DNA Primers / Q000235:genetics; D020868:Gene Silencing; D007333:Insulin Resistance / Q000502:physiology*; D047495:PPAR gamma / Q000378:metabolism*; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D000071222:Suppressor of Cytokine Signaling 1 Protein; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D022762:CCAAT-Enhancer-Binding Proteins; D017931:DNA Primers; D047495:PPAR gamma; C491589:Socs1 protein, rat; C491410:Socs3 protein, rat; D000071222:Suppressor of Cytokine Signaling 1 Protein; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins