title: Blood cells as a source of transcriptional biomarkers of childhood obesity and its related metabolic alterations: results of the IDEFICS study.
abstract: BACKGROUND
  IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants Project) is a European multicenter study on childhood obesity. One of its goals is to define early biomarkers of risk associated with obesity and its comorbid conditions.
  
  
  OBJECTIVE
  We considered blood cells as a new potential source of transcriptional biomarkers for these metabolic disorders and examined whether blood cell mRNA levels of some selected genes (LEPR, INSR, CPT1A, SLC27A2, UCP2, FASN, and PPARα) were altered in overweight children and whether their expression levels could be defined as markers of the insulin-resistant or dyslipidemic state associated with overweight.
  
  
  METHODS
  Blood samples were obtained from 306 normal-weight and overweight children, aged 2-9 yr, from eight different European countries. Whole-blood mRNA levels were assessed by quantitative RT-PCR.
  
  
  RESULTS
  LEPR, INSR, and CPT1A mRNA levels were higher in overweight compared with normal-weight children (the two latter only in males), whereas SLC27A2 mRNA levels were lower in overweight children. Significant associations were also found between expression levels of LEPR, INSR, CPT1A, SLC27A2, FASN, PPARα, and different parameters, including body mass index, homeostasis model assessment index, and plasma triglycerides and cholesterol levels. These associations showed that high expression levels of CPT1A, SLC27A2, INSR, FASN, or PPARα may be indicative of a lower risk for the insulin-resistant or dyslipidemic state associated with obesity, whereas low LEPR mRNA levels appear as a marker of high low-density lipoprotein cholesterol, independently of body mass index.
  
  
  CONCLUSIONS
  These findings point toward the possibility of using the expression levels of these genes in blood cells as markers of metabolic status and can potentially provide an early warning of a future disorder.
authors.affiliation: Laboratory of Molecular Biology, Nutrition, and Biotechnology (Nutrigenomics), University of the Balearic Islands (UIB), Campus de la Carretera. Valldemossa Km 7.5, Palma de Mallorca 07122, Spain.
authors.forename: Juana
authors.initials: J
authors.lastname: Sánchez
authors.forename: Teresa
authors.initials: T
authors.lastname: Priego
authors.forename: Catalina
authors.initials: C
authors.lastname: Picó
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Ahrens
authors.forename: Stefaan
authors.initials: S
authors.lastname: De Henauw
authors.forename: Arno
authors.initials: A
authors.lastname: Fraterman
authors.forename: Staffan
authors.initials: S
authors.lastname: Mårild
authors.forename: Dénes
authors.initials: D
authors.lastname: Molnár
authors.forename: Luis A
authors.initials: LA
authors.lastname: Moreno
authors.forename: Jenny
authors.initials: J
authors.lastname: Peplies
authors.forename: Paola
authors.initials: P
authors.lastname: Russo
authors.forename: Alfonso
authors.initials: A
authors.lastname: Siani
authors.forename: Michael
authors.initials: M
authors.lastname: Tornaritis
authors.forename: Toomas
authors.initials: T
authors.lastname: Veidebaum
authors.forename: Andreu
authors.initials: A
authors.lastname: Palou
mesh_terms: D015703:Antigens, CD / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D001773:Blood Cells / Q000378:metabolism; D015992:Body Mass Index; D002334:Carnitine O-Palmitoyltransferase / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003066:Coenzyme A Ligases / Q000097:blood / Q000235:genetics / Q000378:metabolism; D015331:Cohort Studies; D005060:Europe; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D006949:Hyperlipidemias / Q000209:etiology*; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000097:blood* / Q000378:metabolism* / Q000503:physiopathology; D012333:RNA, Messenger / Q000097:blood / Q000378:metabolism; D011972:Receptor, Insulin / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D054411:Receptors, Leptin / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D012727:Sex Characteristics; D000098859:Long-Chain-Fatty-Acid-CoA Ligase
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; C515448:LEPR protein, human; D012333:RNA, Messenger; D054411:Receptors, Leptin; D002334:Carnitine O-Palmitoyltransferase; C435941:INSR protein, human; D011972:Receptor, Insulin; D003066:Coenzyme A Ligases; D000098859:Long-Chain-Fatty-Acid-CoA Ligase