title: Biomarkers of Alzheimer disease, insulin resistance, and obesity in childhood.
abstract: OBJECTIVE
  To answer the question of whether onset of insulin resistance (IR) early in life enhances the risk of developing dementia and Alzheimer disease (AD), serum levels of 2 molecules that are likely associated with development of AD, the amyloid β-protein 42 (Aβ42) and presenilin 1 (PSEN1), were estimated in 101 preschoolers and 309 adolescents of various BMI.
  
  
  METHODS
  Participants (215 boys; 48.8%) were normal weight (n = 176; 40%), overweight (n = 135; 30.7%), and obese (n = 129; 29.3%). The HOmeostasis Model of IR (HOMA-IR), HOMA percent β-cell function (HOMA-β) and QUantitative Insulin-sensitivity Check Index (QUICKI) were calculated.
  
  
  RESULTS
  Obese adolescents had values of Aβ42 higher than overweight and normal-weight peers (190.2 ± 9.16 vs 125.9 ± 7.38 vs 129.5 ± 7.65 pg/mL; P < .0001) as well as higher levels of PSEN1 (2.34 ± 0.20 vs 1.95 ± 0.20 vs 1.65 ± 0.26 ng/mL; P < .0001). Concentrations of Aβ42 were significantly correlated with BMI (ρ = 0.262; P < .0001), HOMA-IR (ρ = 0.261; P < .0001) and QUICKI (ρ = -0.220; P < .0001). PSEN1 levels were correlated with BMI (ρ = 0.248; P < .0001), HOMA-IR (ρ = 0.242; P < .0001), and QUICKI (ρ = -0.256; P < .0001). Western blot analysis confirmed that PSEN1 assays measured the full-length protein.
  
  
  CONCLUSIONS
  Obese adolescents with IR present higher levels of circulating molecules that might be associated with increased risk of developing later in elderly cognitive impairment, dementia, and AD.
authors.affiliation: Department of Laboratory Medicine.
authors.forename: Rosa
authors.initials: R
authors.lastname: Luciano
authors.affiliation: Research Unit for Multi-factorial Diseases, Scientific Directorate, and.
authors.forename: Gloria Maria
authors.initials: GM
authors.lastname: Barraco
authors.affiliation: Department of Laboratory Medicine.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Muraca
authors.affiliation: Department of Laboratory Medicine.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Ottino
authors.affiliation: Unit for Clinical Nutrition, Bambino Gesù Children's Hospital, Rome, Italy.
authors.forename: Maria Rita
authors.initials: MR
authors.lastname: Spreghini
authors.affiliation: Unit for Clinical Nutrition, Bambino Gesù Children's Hospital, Rome, Italy.
authors.forename: Rita Wietrzykowska
authors.initials: RW
authors.lastname: Sforza
authors.affiliation: Unit for Clinical Nutrition, Bambino Gesù Children's Hospital, Rome, Italy.
authors.forename: Carmela
authors.initials: C
authors.lastname: Rustico
authors.affiliation: Unit for Clinical Nutrition, Bambino Gesù Children's Hospital, Rome, Italy.
authors.forename: Giuseppe Stefano
authors.initials: GS
authors.lastname: Morino
authors.affiliation: Research Unit for Multi-factorial Diseases, Scientific Directorate, and melania.manco@opbg.net.
authors.forename: Melania
authors.initials: M
authors.lastname: Manco
mesh_terms: D000293:Adolescent; D000544:Alzheimer Disease / Q000097:blood; D016229:Amyloid beta-Peptides / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D053764:Presenilin-1 / Q000097:blood*
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D010446:Peptide Fragments; D053764:Presenilin-1; C075222:amyloid beta-protein (1-42)