Paraoxonase 1 activity in patients with chronic obstructive pulmonary disease.
BACKGROUND
Paraoxonase 1 (PON1) is an antioxidative enzyme manly associated with high density lipoproteins (HDL) in the peripheral blood. The aim of this study was to determine the PON1 paraoxonase and arylesterase activities in patients with chronic obstructive pulmonary disease (COPD). We also aimed to determine the concentration of reduced thiol groups as a marker of protein oxidation.


METHODS
The study included 105 patients with stable COPD and 44 healthy controls. PON1 activities and thiols concentration were assayed in sera by spectrophotometry.


RESULTS
PON1 basal (POX) and salt-stimulated paraoxonase activity (POX1) as well as arylesterase activity (ARE) were significantly reduced in COPD patients. In addition, concentration of reduced thiol groups was significantly decreased in COPD group. PON1 activities were similar in patients with different disease severity (GOLD stages). However, a significant reduction in POX, POX1 and ARE was observed already in GOLD II stage when compared to controls. POX and POX1 showed modest while ARE yielded very good power for discrimination between healthy subjects and COPD patients. Univariate and multivariate logistic regression analysis indicated that ARE is a good COPD predictor.


CONCLUSIONS
Reduction of PON1 activity observed in COPD patients could be partly caused by oxidative environment. Lower concentrations of reduced thiol groups in COPD patients suggest that a decrease in PON1 activity could reflect oxidative changes of enzyme free cysteine residues. Furthermore, decreased PON1 arylesterase activity might indicate a down-regulation of PON1 concentration. Our results suggest that ARE could be considered as potential biomarker for COPD diagnosis.
1Department of Medical Biochemistry and Hematology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb , Croatia.
Lada
L
Rumora
Marija Grdić
MG
Rajković
Lara Milevoj
LM
Kopčinović
Dolores
D
Pancirov
Ivana
I
Čepelak
Tihana Žanić
TŽ
Grubišić
D000368:Aged; D043303:Aryldialkylphosphatase / Q000378:metabolism*; D016022:Case-Control Studies; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010261:Paraoxon / Q000378:metabolism; D010648:Phenylacetates / Q000378:metabolism; D029424:Pulmonary Disease, Chronic Obstructive / Q000201:enzymology* / Q000378:metabolism / Q000503:physiopathology; D012720:Severity of Illness Index; D012907:Smoking / Q000378:metabolism*; D013053:Spectrophotometry; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D014797:Vital Capacity
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D010648:Phenylacetates; D013438:Sulfhydryl Compounds; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human; C025136:phenylacetic acid; D010261:Paraoxon
arylesterase activity; chronic obstructive pulmonary disease; oxidative stress; paraoxonase 1; paraoxonase activity; thiols