title: Paraoxonase 1 activity and phenotype distribution in premenopausal and postmenopausal women.
abstract: BACKGROUND
  Postmenopausal women have higher risk of cardiovascular disease. One of the contributing factors could be reduced activity of anti-atherogenic enzyme paraoxonase 1 (PON1). The aim of this study was to examine differences in the lipid status, paraoxonase and arylesterase PON1 activities and PON1 phenotype in women with regular menstrual cycle and in postmenopausal women.
  
  
  METHODS
  The study included 51 women in reproductive age (25 in follicular and 26 in luteal phase of the menstrual cycle) and 23 women in postmenopause. Lipid parameters in sera were determined using original reagents and according to manufacturer protocol. PON1 activity in serum was assessed by spectrophotometric method with substrates: paraoxon and phenylacetate. PON1 phenotype was determined by double substrate method.
  
  
  RESULTS
  Compared to the women in follicular and luteal phase, postmenopausal women have significantly higher concentration of triglyceride [0.9 (0.7-1.3), 0.7 (0.6-1.0) vs. 1.5 (0.9-1.7) mmol/L; P = 0.002], cholesterol [5.10 (4.78-6.10), 5.05 (4.70-5.40) vs. 6.30 (5.73-7.23) mmol/L; P < 0.001], LDL [3.00 (2.56-3.63), 3.00 (2.70-3.70) vs. 3.90 (3.23-4.50) mmol/L; P < 0.001], and apolipoprotein B [0.88 (0.75-1.00), 0.79 (0.68-1.00) vs. 1.07 (0.90-1.24) mmol/L; P = 0.002]. PON1 basal [104 (66-260), 106 (63-250) vs. 93 (71-165) U/L; P = 0.847] and salt-stimulated paraoxonase activity [210 (131-462), 211 (120-442) vs. 180 (139-296) U/L; P = 0.857] as well as arylesterase activity [74 (63-82), 70 (54-91) vs. 70 (60-81) kU/L; P = 0.906] and PON1 phenotype (P = 0.810) were not different in the study groups.
  
  
  CONCLUSIONS
  There are no differences in PON1 activity and PON1 phenotype between women with regular menstrual cycle and postmenopausal women.
authors: Clinic of Gynecology and Obstetrics, Medical School University Hospital Sestre Milosrdnice, Zagreb, Croatia.
authors: Dražan
authors: D
authors: Butorac
authors: Ivana
authors: I
authors: Celap
authors: Sanja
authors: S
authors: Kačkov
authors: Vera
authors: V
authors: Robić
authors: Tomislav
authors: T
authors: Miletić
authors: Zlata Flegar
authors: ZF
authors: Meštrić
authors: Andrea
authors: A
authors: Hulina
authors: Krunoslav
authors: K
authors: Kuna
authors: Tihana Žanić
authors: TŽ
authors: Grubišić
authors: Marija Grdić
authors: MG
authors: Rajković
mesh_terms: D000328:Adult; D001055:Apolipoproteins B / Q000097:blood; D043303:Aryldialkylphosphatase / Q000097:blood*; D002265:Carboxylic Ester Hydrolases / Q000097:blood*; D016022:Case-Control Studies; D002784:Cholesterol / Q000097:blood; D005260:Female; D005498:Follicular Phase / Q000097:blood; D006801:Humans; D008183:Luteal Phase / Q000097:blood; D008875:Middle Aged; D010641:Phenotype; D017698:Postmenopause / Q000097:blood*; D017697:Premenopause / Q000097:blood*; D014280:Triglycerides / Q000097:blood
chemical_list: D001055:Apolipoproteins B; D014280:Triglycerides; D002784:Cholesterol; D002265:Carboxylic Ester Hydrolases; C019734:arylesterase; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human