The paraoxonase 1, 2 and 3 in humans.
ABSTRACT The paraoxonase gene family in humans includes three members: PON1, PON2 and PON3. The products of those three genes are the following enzymes: paraoxonase 1 (PON1), paraoxonase 2 (PON2) and paraoxonase 3 (PON3). PON1 is mainly associated with a high density lipoprotein (HDL). A small amount of this enzyme is also bound to very low-density lipoprotein (VLDL) and postprandial chylomicrons. PON1 possess organophosphatase, arylesterase and lactonase activity and it hydrolyzes many different substrates. It is also known that PON1 may have antiatherogenic function. Compared to the PON1, PON2 and PON3 are much less studied and described. PON2 is ubiquitously expressed intracellular protein, while PON3 is bound to HDL, like PON1. The both enzymes possess antioxidant properties.
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ABSTRACT: 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.Biochemia Medica 01/2014; 24(2):273-80. DOI:10.11613/BM.2014.030 · 2.40 Impact Factor
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ABSTRACT: Abstract Introduction: 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. Materials and 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. Conclusion: 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.COPD Journal of Chronic Obstructive Pulmonary Disease 05/2014; 11(5). DOI:10.3109/15412555.2014.898028 · 2.62 Impact Factor
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ABSTRACT: The measurement of the total radical trapping antioxidant potential (TRAP) is a general marker of peripheral blood antioxidant defenses. Paraoxonase 1 (PON1) is a potent antioxidant, which protects against lipid peroxidation. The study aimed to examine the relation between TRAP levels and PON1 activity, PON1 Q192R functional genotypes, smoking, interactions between PON1 genotypes and smoking, and mood disorders, while adjusting for effects of ethnicity, marital status, body mass index (BMI) and gender. The analyses were performed in 197 controls and 136 subjects with mood disorders. TRAP levels were significantly associated with higher plasma PON1 activity, the RR functional genotype, non smoking by RR carriers, male gender and a higher BMI. TRAP levels were significantly lower in patients with mood disorders than in controls, but this association was no longer significant after considering the effects of the above predictors. The risk in the subgroup with low TRAP levels is increased by a smoking X RR genotype interaction and decreased by male gender, the RR genotype, and higher BMI and PON1 activity. Plasma PON1 activity, the PON1 Q192R functional genotypes and specific interactions between this genotype and smoking contribute significantly to TRAP levels. Gender and BMI also appear to influence TRAP levels.Neuroscience Letters 08/2014; 581. DOI:10.1016/j.neulet.2014.08.020 · 2.06 Impact Factor