title: Lowering of circulating free-fatty acids levels and reduced expression of leptin in white adipose tissue in postobesity status.
abstract: BACKGROUND
  Our aim was to investigate the regulation of the gene expression of leptin in subcutaneous adipose tissue biopsies in morbid obesity before and after biliopancreatic diversion (BPD).
  
  
  METHODS
  Longitudinal study in morbidly obese subjects investigated twice: before and 6 months after BPD. Fourteen morbidly obese women, 37+/-13 years old and with a body mass index of 51.6+/-8.2 kg/m2, were studied before and 6 months after BPD (40.6+/-8.0 kg/m2). Using reverse transcriptase polymerase chain reaction analysis, the mRNA expression of leptin was investigated in adipose tissue. Plasma leptin was measured by radioimmunoassay; plasma insulin was measured by microparticle enzyme immunoassay. Free fatty acids (FFA) were measured using a colorimetric kit.
  
  
  RESULTS
  A significant decrease in leptin mRNA level was observed in comparison with pretreatment in BPD patients (59+/-34 vs 143+/-85 arbitrary units, P<0.01). A strict relationship between adipose tissue leptin mRNA and plasma leptin either before (R2=0.80, P<0.0001) or after BPD (R2=0.86, P<0.0001) and between plasma FFA concentration and insulin either before (R2=0.65, P<0.001) or after BPD (R2=0.92, P<0.0001) was observed. Finally, a significant correlation was found between changes in FFA and insulin (R2=0.64, P<0.001), insulin and leptin (R2=0.88, P<0.0001), and insulin and leptin mRNA (R2=0.83, P<0.0001).
  
  
  CONCLUSIONS
  These data demonstrate a high correlation between leptin mRNA expression in adipose tissue and plasma leptin in postobese subjects after BPD. The significant relationship between both leptin mRNA and plasma leptin with insulin suggests that circulating insulin might regulate leptin expression. It might be hypothesized that plasma FFA concentration can act on the insulin secretion and subsequently on the leptin secretory pathway.
authors.affiliation: Istituto di Medicina Interna, Università Cattolica S. Cuore, Rome, Italy. agreco@rm.unicatt.it
authors.forename: Aldo V
authors.initials: AV
authors.lastname: Greco
authors.forename: Geltrude
authors.initials: G
authors.lastname: Mingrone
authors.forename: Roberto
authors.initials: R
authors.lastname: Vettor
authors.forename: Melania
authors.initials: M
authors.lastname: Manco
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Rosa
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Capristo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Federspil
authors.forename: Marco
authors.initials: M
authors.lastname: Castagneto
authors.forename: Giovanni
authors.initials: G
authors.lastname: Gasbarrini
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000886:Anthropometry; D005215:Fasting; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000235:genetics / Q000378:metabolism*; D008137:Longitudinal Studies; D009767:Obesity, Morbid / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D005230:Fatty Acids, Nonesterified; D007328:Insulin; D020738:Leptin; D012333:RNA, Messenger