Association of paraoxonase activity and coronary collateral flow

The Importance of Pan-Immune Inflammation Value (PIV) in Predicting Coronary Collateral Circulation in Stable Coronary Artery Patients

In this study, the correlation between pan-immune-inflammation value (PIV) and coronary collateral circulation (CCC) in patients with chronic coronary syndrome (CCS) was analyzed. The study included 663 patients with CCS who underwent coronary angiography and had coronary stenosis of ≥95% in at least one major coronary vessel. The participants were divided into two groups: good CCC (Rentrop score 2-3) and poor CCC (Rentrop score 0-1). PIV score was calculated as monocyte x platelet x neutrophil/lymphocyte count. When the patient groups who developed good and poor CCC were compared, neutrophil/lymphocyte ratio (NLR) (P < .001), C-reactive protein (CRP) levels, CRP/albumin ratio (CAR) (P < .001), systemic immune-inflammation index (SII) (P < .001), and PIV (P < .001) were higher in patients with poor CCC. In multivariate logistic regression analysis, age, SII, NLR, CRP, CAR, and PIV were found to be independent predictors of poor CCC (P < .001, for all). Receiver operating characteristic (ROC) analysis demonstrated that a cut-off value of 442.2 for PIV predicted poor CCC slightly better compared to other markers, with 76.8% sensitivity and 70.1% specificity (area under ROC curve = 0.808 (95% CI: 0.764-0.851), P < .001). These findings suggest that PIV can be used as an independent predictor of CCC development.

Association between Hemogram Parameters and Coronary Collateral Development in Subjects with Non-ST-Elevation Myocardial Infarction

OBJECTIVE

Coronary collateral development (CCD) predicts the severity of coronary heart disease. Hemogram parameters, such as mean platelet volume (MPV), eosinophil, red cell distribution width, and platelet distribution width (PDW), are supposed novel inflammatory markers. We aimed to compare hemogram parameter values in patients presenting with non-ST-elevation myocardial infarction (NSTEMI) with adequate or inadequate CCD.

METHODS

A total of 177 patients with NSTEMI undergoing coronary arteriography were enrolled and divided into two groups based on the development of CCD: one group with adequate CCD (n=88) and the other with impaired CCD (n=89).

RESULTS

Baseline demographics and clinical risk factors were similar between the groups. Hemogram parameters were not significantly different between the two groups. However, compared to the inadequate CCD group, the median PDW was significantly higher in the adequate CCD group, 17.6 (1.4) vs. 17.8 (1.6) p=0.004. In a multivariate analysis, PDW (p=0.001, 95% CI for OR: 0.489(0,319-0,750) was found to be significantly different in the adequate CCD group compared to the inadequate CCD group. Pearson's correlation analysis revealed that PDW was significantly correlated with the Rentrop score (r=0.26, p<0.001).

CONCLUSIONS

We suggest that since PDW is an index that is inexpensive and easy to assess, it could serve as a marker of CCD in patients with NSTEMI.

Relationship between internal and external factors and the activity of PON1

Paraoxonase 1 (PON1) is an A-esterase calcium-dependent enzyme that is associated with high-density lipoprotein (HDL) and capable of hydrolyzing a wide variety of substrates, including organophosphate (OP) pesticides. The PON1 phenotype can be modulated by multiple internal and external factors, thereby affecting the catalytic capacity of the enzyme. The aim of this study was to evaluate factors that could modulate PON1 activity in a sample occupationally exposed to pesticides. A cross-sectional, descriptive, and analytical study was carried out with 240 workers. The participants were stratified according to their level of pesticide exposure as reference, moderate-exposure, and high-exposure groups. PON1 activities (arylesterase/AREase, CMPAase, and ssPONase (salt-stimulated)) were determined by spectrophotometry, and the Q192R and L55MPON1 genotypes by real-time PCR. The most frequent genotypes were heterozygous (QR) and homozygous (LL) for PON1Q192R and PON1L55M polymorphisms, respectively. The internal factors associated with the activity of PON1 were the PON1 genotypes (55 and 192) and biochemical parameters related to the lipid profile, in contrast, various external factors related to diet and harmful habits as well as with exposure to pesticides were associated with the activity of PON1. However, using a multivariate mixed ordinal regression model, we found a significant reduction of ssPONase activity in the high-exposure group compared with the reference group only in haplotypes QQLL and RRLL.

High-density lipoprotein-associated paraoxonase-1 activity for prediction of adverse outcomes in outpatients with chronic heart failure

AIMS

Decreased arylesterase (ArylE) activity of paraoxonase-1, a HDL-associated protein with anti-inflammatory and antioxidant properties, has been associated with increased risk of cardiac events in patients with ischaemic heart failure (HF). We aim to investigate the prognostic significance of changes in serum ArylE activity over time.

METHODS AND RESULTS

We examined the association between baseline and follow-up serum ArylE activity and HF outcomes (death, cardiac transplantation, or ventricular assist device implantation) in 299 patients with HF enrolled in a prospective cohort study from January 2008 to July 2009, with 145 patients having available follow-up levels at 1 year. A significant drop in ArylE activity on follow-up was defined as a drop of ≥25% vs. baseline levels. Mean baseline and follow-up ArylE activity levels were 110.6 ± 29.9 µmol/min/mL and 106.2 ± 29.9 µmol/min/mL, respectively. After a mean follow-up of 2.8 ± 1.1 years, low baseline ArylE activity was associated with increased risk of adverse HF events [hazard ratio (HR; lowest vs highest tertile) 2.6, 95% confidence interval (CI) 1.3-5.5, P = 0.01] and HF-related hospitalization [incidence rate ratio (lowest vs. highest tertile) 2.1, 95% CI 1.2-4.1, P = 0.016], which remained significant after adjustment for age, male gender, systolic blood pressure, diabetes, creatinine clearance, CAD, and HDL-cholesterol levels. Patients who had a significant drop in ArylE activity on follow-up (n = 18) had a significantly increased risk of HF events (HR 4.9, 95% CI 1.6-14.6, P = 0.005), even after adjustment for baseline levels of ArylE activity.

CONCLUSIONS

Reduced baseline ArylE activity and decreased levels on follow-up are associated with adverse outcomes in stable outpatients with HF.

An evaluation of serum paraoxonase together with arylesterase activities and oxidative stress in children with intractable epilepsy: a cross-sectional study

Epilepsy is the most common chronic neurological illness in childhood and adolescence. The aim of this study was to investigate paraoxonase and arylesterase activities along with oxidative status parameters in children with intractable epilepsy. The study comprised 42 subjects with intractable epilepsy and a control group of 35 healthy subjects. Serum paraoxonase and arylesterase activities, and lipid hydroperoxide levels were determined. All paraoxonase and arylesterase activities were significantly lower in the intractable epilepsy subjects than in the controls (P<0.001), whereas lipid hydroperoxide levels were significantly higher (P<0.05). In conclusion, paraoxonase and arylesterase activities were decreased and the lipid hydroperoxide level was increased in patients with intractable epilepsy. These results showed that intractable epilepsy subjects may be more prone to the development of atherosclerosis.

The effect of age on the paraoxonase and arylesterase activity of pregnant mothers and their infants

AIM

The study aimed to research the effect of maternal age at pregnancy on the paraoxonase (PON) and arylesterase activity levels of mothers and infants.

METHOD

The study comprised 30 mothers aged more than 35 years and their infants, and 30 mothers aged under 25 years and their infants. All pregnancies had been of 38-42 weeks with normal spontaneous vaginal birth. PON and arylesterase activities were measured using paraoxon and phenylacetate substrates.

RESULTS

When the PON and arylesterase enzyme activities were compared, the PON and arylesterase activity of the mothers aged more than 35 years was found to be statistically significantly lower compared to that of the mothers aged under 25 years (P = 0.006 and P = 0.03, respectively), while there was no statistically significant difference in PON and arylesterase enzyme activity between the two groups of infants (P > 0.05).

CONCLUSION

While the PON and arylesterase enzyme activity of the mothers aged more than 35 years was found to be significantly lower compared to that of the mothers aged under 25 years, there was no statistical significance between the infants. This can be explained by the reduced PON and arylesterase enzyme activity during pregnancies at an older age, although this did not affect the PON and arylesterase enzyme activity of the infants.

Paraoxonase and arylesterase activities in children with iron deficiency anemia and vitamin B12 deficiency anemia

Paraoxonase-1 is an esterase enzyme and it has 3 types of activity, namely paraoxonase, arylesterase, and diazoxonase. It has been reported that paraoxonase-1 deficiency is related to increased susceptibility to development of atherosclerosis and cardiovascular disease. The aim of this study was to investigate serum paraoxonase and arylesterase activities in children with iron deficiency anemia and vitamin B(12) deficiency anemia. Thirty children with iron deficiency anemia, 30 children with vitamin B(12) deficiency anemia, and 40 healthy children aged 6 months to 6 years were enrolled in this study. Serum paraoxonase and arylesterase activities were measured with a spectrophotometer by using commercially available kits. Mean paraoxonase and arylesterase activities in vitamin B(12) deficiency anemia group (103 ± 73 and 102 ± 41 U/L, respectively) were significantly lower than mean activities of control group (188 ± 100 and 147 ± 34 U/L, respectively; P < .001 for both) and iron deficiency anemia group (165 ± 103 and 138 ± 39 U/L, respectively; P < .05, P < .001), whereas there were no significant differences between iron deficiency anemia and control groups (P > .05). Paraoxonase and arylesterase activities significantly increased after treatment with vitamin B(12) in vitamin B(12) deficiency anemia; however, there were no significant changes in the activities of these enzymes after iron treatment in iron deficiency anemia group. Important correlations were found between vitamin B(12) levels and both paraoxonase and arylesterase activities (r = .367, P < .001; r = .445, P < .001). Our results suggest that vitamin B(12) deficiency anemia causes important reductions in paraoxonase and arylesterase activities, and after vitamin B(12) therapy the activities of these enzymes returned to near-normal levels.

Evaluation of the future atherosclerotic heart disease with oxidative stress and carotid artery intima media thickness in gestational diabetes mellitus

BACKGROUND AND OBJECTIVE

In this study our aim was to evaluate paraoxonase (PON1) activity and free sulfhydryl groups (-SH) as antioxidative parameters and lipid hydroperoxide (LOOH) as oxidative parameter in the serum of women with gestational diabetes mellitus (GDM) and determine their relation with the degree of subclinical atherosclerosis.

MATERIAL AND METHODS

Serum samples from 39 pregnant women complicated with GDM and 40 healthy pregnant women were collected for the analysis of oxidative markers. Common carotid artery intima media thickness (CIMT) was measured for both groups to assess future atherosclerotic heart disease risk. PON1 activity and -SH were measured spectrophotometrically. LOOH levels were measured by ferrous oxidation with a xylenol orange assay.

RESULTS

CIMT and LOOH levels were significantly higher (p = 0.01, p < 0.001, respectively) in GDM group compared to controls, whereas PON1 and -SH levels were significantly lower (p < 0.001 for both). CIMT values were significantly correlated with body mass index (BMI), 50 g oral glucose tolerance test (OGTT), and mean arterial blood pressure (MABP) (p = 0.003, p = 0.02, and p = 0.03, respectively). However, there was no correlation between CIMT and oxidative markers.

CONCLUSIONS

Increased levels of LOOH and decreased levels of PON1 and -SH showed disturbance of antioxidative mechanisms in GDM. These changes were associated with increased BMI and MABP which may be relevant to GDM pathophysiology. Furthermore, increased CIMT values in GDM compared to healthy controls designate increased risk of future atherosclerotic heart disease.