title: Impaired paraoxonase-1 status in obese children. Relationships with insulin resistance and metabolic syndrome.
abstract: OBJECTIVE
  To investigate the relationships between serum paraoxonase-1 (PON1), insulin resistance, and metabolic syndrome (MetS) in childhood obesity.
  
  
  METHODS
  We studied 110 obese children and 36 non-obese children with a similar gender and age distribution. We measured serum PON1 activity against 5-thiobutyl butyrolactone (TBBLase) and against paraoxon (paraoxonase). PON1 concentration was measured separately as were the levels of several standard metabolic variables. The homeostasis model assessment (HOMA) index was calculated as an estimate of insulin resistance.
  
  
  RESULTS
  TBBLase was significantly decreased in obese children (P=0.008), while paraoxonase activity and PON1 concentrations showed non-significant trends towards decrease and increase, respectively (P=0.054 and P=0.060). TBBLase and paraoxonase specific activities were significantly decreased (P=0.004 and P=0.018, respectively). TBBLase specific activity was inversely associated with BMI, percentage body fat, insulin, HOMA, triglycerides, and C-reactive protein, and directly associated with HDL-cholesterol. Paraoxonase specific activity showed similar associations with BMI, percentage fat, HDL-cholesterol, and C-reactive protein. Obese children with MetS had lower TBBLase activities than obese children without MetS (P=0.018). Linear regression analyses showed that TBBLase was independently associated with HDL-cholesterol, BMI, percentage body fat and PON155 polymorphism, but paraoxonase activity was associated only with PON1192 polymorphism.
  
  
  CONCLUSIONS
  Our results suggest that PON1 may play a role in the onset and development of metabolic alterations in childhood obesity leading to diabetes and cardiovascular disease later in life. However, being derived from statistical association study, this finding cannot be seen as showing cause-effect.
authors.affiliation: Unitat de Pediatria, Institut d'Investigació Sanitària Pere Virgili, Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, Reus, Spain.
authors.forename: Natàlia
authors.initials: N
authors.lastname: Ferré
authors.forename: Albert
authors.initials: A
authors.lastname: Feliu
authors.forename: Anabel
authors.initials: A
authors.lastname: García-Heredia
authors.forename: Judit
authors.initials: J
authors.lastname: Marsillach
authors.forename: Neus
authors.initials: N
authors.lastname: París
authors.forename: Marta
authors.initials: M
authors.lastname: Zaragoza-Jordana
authors.forename: Bharti
authors.initials: B
authors.lastname: Mackness
authors.forename: Michael
authors.initials: M
authors.lastname: Mackness
authors.forename: Joaquín
authors.initials: J
authors.lastname: Escribano
authors.forename: Ricardo
authors.initials: R
authors.lastname: Closa-Monasterolo
authors.forename: Jorge
authors.initials: J
authors.lastname: Joven
authors.forename: Jordi
authors.initials: J
authors.lastname: Camps
mesh_terms: D000293:Adolescent; D043303:Aryldialkylphosphatase / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000201:enzymology*; D063766:Pediatric Obesity / Q000201:enzymology*; D011110:Polymorphism, Genetic; D012044:Regression Analysis; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D014280:Triglycerides; D002097:C-Reactive Protein; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human
keywords: Insulin resistance; Metabolic syndrome; Obesity; Paraoxonase-1