title: Triiodothyronine modulates the expression of leptin and adiponectin in 3T3-L1 adipocytes.
abstract: OBJECTIVE
  To study the effect of different doses of triiodothyronine on gene expression of the adipokines leptin and adiponectin, at different times, and to evaluate the difference in expression between the two adipokines in each group.
  
  
  METHODS
  3T3-L1 adipocytes were incubated with triiodothyronine at physiological dose (10nM) and supraphysiological doses (100nM or 1,000nM), or without triiodothyronine (control, C) for 0.5, 6, or 24 hours. Leptin and adiponectin mRNA was detected using real-time polymerase chain reaction (RT-PCR). One-way analyses of variance, Tukey's test or Student's t test, were used to analyze data, and significance level was set at 5%.
  
  
  RESULTS
  Leptin levels decreased in the 1,000nM-dose group after 0.5 hour. Adiponectin levels dropped in the 10nM-dose group, but increased at the 100nM dose. After 6 hours, both genes were suppressed in all hormone concentrations. After 24 hours, leptin levels increased at 10, 100 and 1,000nM groups as compared to the control group; and adiponectin levels increased only in the 100nM group as compared to the control group.
  
  
  CONCLUSIONS
  These results demonstrated fast actions of triiodothyronine on the leptin and adiponectin expression, starting at 0.5 hour, at a dose of 1,000nM for leptin and 100nM for adiponectin. Triiodothyronine stimulated or inhibited the expression of adipokines in adipocytes at different times and doses which may be useful to assist in the treatment of obesity, assuming that leptin is increased and adiponectin is decreased, in obesity cases.
authors.affiliation: Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil.
authors.forename: Miriane de
authors.initials: Md
authors.lastname: Oliveira
authors.affiliation: Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: de Síbio
authors.affiliation: Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil.
authors.forename: Regiane Marques Castro
authors.initials: RM
authors.lastname: Olimpio
authors.affiliation: Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil.
authors.forename: Fernanda Cristina Fontes
authors.initials: FC
authors.lastname: Moretto
authors.affiliation: Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
authors.forename: Renata de Azevedo Melo
authors.initials: Rde A
authors.lastname: Luvizotto
authors.affiliation: Universidade Estadual Paulista "Júlio de Mesquita Filho", Botucatu, SP, Brazil.
authors.forename: Celia Regina
authors.initials: CR
authors.lastname: Nogueira
mesh_terms: D041721:3T3-L1 Cells / Q000187:drug effects*; D017667:Adipocytes / Q000187:drug effects*; D052242:Adiponectin / Q000032:analysis / Q000235:genetics*; D000704:Analysis of Variance; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D015870:Gene Expression / Q000187:drug effects*; D020738:Leptin / Q000032:analysis / Q000235:genetics*; D051379:Mice; D009765:Obesity / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction; D012016:Reference Values; D013997:Time Factors; D014284:Triiodothyronine / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D052242:Adiponectin; D020738:Leptin; D012333:RNA, Messenger; D014284:Triiodothyronine