title: Paraoxonase-1 activities in children and adolescents with type 1 diabetes mellitus.
abstract: Paraoxonase-1 is an HDL-associated esterase that acts as an anti-atherogenic agent by protecting LDL from oxidation. This study investigates paraoxonase-1 activities in children and adolescents with type 1 diabetes mellitus and possible associations with other biochemical markers.
  
  
  
  The study enrolled 82 children and adolescents with type 1 diabetes mellitus and 41 controls with similar age and gender distribution. Serum paraoxonase-1 arylesterase and salt-stimulated paraoxonase activities were assessed by measuring the rates of phenyl acetate and paraoxon hydrolysis, respectively; paraoxonase-1 lactonase activity and oxidized LDL were assessed by a pH-sensitive colorimetric assay and ELISA, respectively. Glycated haemoglobin HbA1c and lipid profile were assayed with an immunoturbidimetric method and commercially available kits, respectively.
  
  
  
  We found lower paraoxonase-1 activities in diabetics when compared to controls. The decrease was statistically significant only for the lactonase activity, the difference being higher when referring to the subgroup with poor glycaemic control. The lactonase activity/HDL ratio was also lower in diabetics vs. controls, but without statistical significance. Both lactonase and arylesterase activities were negatively correlated with HbA1c in diabetics, but only the latter was statistically significant (ρ = -0.21, P = 0.055; ρ = -0.24, P = 0.03, respectively). A correlation coefficient of ρ = 0.196 (P = 0.078) was found between oxidized LDL and HbA1c.
  
  
  
  All paraoxonase-1 activities were lower in diabetic children and adolescents, but only the decrease in the lactonase activity was statistically significant. Although lipid profile and glycaemic control were altered in diabetics, no differences were observed between groups regarding oxidized LDL level.
authors.affiliation: Department of Pharmaceutical Biochemistry and Clinical Laboratory, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Elena C
authors.initials: EC
authors.lastname: Craciun
authors.affiliation: Department of Medical Informatics and Biostatistics, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Leucuta
authors.affiliation: Department of Molecular Sciences, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Razvan L
authors.initials: RL
authors.lastname: Rusu
authors.affiliation: Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Bianca A
authors.initials: BA
authors.lastname: David
authors.affiliation: Paediatric Emergency County Hospital, 1th Paediatric Clinic, Cluj-Napoca, Romania.
authors.forename: Victoria
authors.initials: V
authors.lastname: Cret
authors.affiliation: Department of Molecular Sciences, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Dronca
mesh_terms: D000293:Adolescent; D043303:Aryldialkylphosphatase / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male
chemical_list: D043303:Aryldialkylphosphatase; C468406:PON1 protein, human