Serum Paraoxonase Activity Research Articles

Paraoxonase1, its Q192R polymorphism and HDL-cholesterol in relation to intensive cardiac care unit stay in ischemic heart disease.

AIMS AND OBJECTIVES:The present study was evaluated the atheroprotective potential of paraoxonase1 (PON1) and its Q192R polymorphism, to determine whether this polymorphism, which is responsible for differential PON1 activity plays any role in the pathogenesis, severity and extent of coronary artery disease (CAD).MATERIALS AND METHODS:This hospital-based cross-sectional study investigated 60 diagnosed cases of CAD and 60 age and gender matched controls. All were assessed for serum PON1 activity, PON1 Q192R polymorphism and for classical cardiovascular risk factors. Individual serum phenotyping for PON1 Q192R polymorphism was determined by double substrate hydrolysis assay. Severity of CAD was assessed by the length of intensive cardiac care unit (ICCU) stay.RESULTS:Serum PON1 activity is significantly reduced in cases of CAD (92.6 ± 31.13 IU/L when compared with controls (105.26 ± 32.53 IU/L). Furthermore, serum arylesterase activity is reduced in CAD patients (90.31 ± 23.26 kU) when compared with the control subjects (101.61 ± 28.68 kU). Serum PON1 and arylesterase activities are significantly negatively correlated with the length of ICCU stay (r = −393 and r = −374 respectively). There is no significant difference in the occurrence of CAD and length of ICCU stay among the PON1 phenotypes (P = 0.92). Logistic regression analysis after adjustment of established risk factors revealed no significant association between CAD risk and PON1 Q192R polymorphism (odds ratios: 1.179 [95% confidence intervals: 0.507-2.744], P = 0.702).SUMMARY AND CONCLUSIONS:The current study demonstrates that the activity of the PON1 enzyme may be more important factor than the PON1 Q192R polymorphism in the severity and extent of CAD.

Evaluation of paraoxonase, malondialdehyde, and lipoprotein levels in patients with asymptomatic cholelithiasis

Background/Aim:To compare lipoprotein and malondialdehyde levels and paraoxonase-1 activity between subjects with asymptomatic cholelithiasis and controls.Patients and Methods:Eighty subjects with asymptomatic cholelithiasis (55 women, 25 men, mean age: 51, SD 14 years) and 40 control subjects without cholelithiasis (25 women, 25 men, mean age: 51, SD 12 years) were enrolled to the study. Serum paraoxonase activity, lipoproteins, and malondialdehyde were measured.Results:In the cholelithiasis group, serum total cholesterol, low-density lipoprotein cholesterol, and malondialdehyde were significantly higher and high-density lipoprotein cholesterol (HDL-C) and paraoxonase-1 were significantly lower than the controls. In cholelithiasis patients with serum glucose level > 100 mg/dL, body mass index, serum total cholesterol, triglyceride (TG), and malondialdehyde levels were significantly higher than cholelithiasis patients with serum glucose level < 100 mg/dL. Paraoxonase-1 activity was significantly lower in patients with serum glucose level > 100 mg/dL. In cholelithiasis patients with TG > 150 mg/dL, mean age, body mass index, glucose, total cholesterol, and malondialdehyde were significantly higher than in cholelithiasis patients with TG < 150 mg/dL. In cholelithiasis subgroup with TG > 150 mg/dL, HDL-C level and paraoxonase-1 activity were lower than in the cholelithiasis subgroup with TG < 150 mg/dL. All of the above comparisons were statistically significant (P < 0.05).Conclusions:Patients with asymptomatic cholelithiasis have evidence of increased lipid peroxidation and decreased antioxidant capacity. Patients with asymptomatic cholelithiasis with components of the metabolic syndrome have more lipid peroxidation and less antioxidant capacity than patients with asymptomatic cholelithiasis but without the components of the metabolic syndrome.

Serum paraoxonase activity and oxidative stress and their relationship with obesity-related metabolic syndrome and non-alcoholic fatty liver disease in obese children and adolescents

Oxidative stress has been reported to be involved in the pathogenesis of metabolic disorders related with obesity. The aim of the study was to investigate the association of oxidative stress and paraoxonase activities with non-alcoholic fatty liver disease (NAFLD) as well as metabolic syndrome. A total of 109 obese children and adolescents and 44 healthy and lean control subjects were enrolled in the study. According to their ultrasonographic steatosis scores, they were classified into four groups as follows: healthy children; obese, non-NAFLD; obese, grade I-NAFLD; and obese, grade II-III NAFLD. The biochemical parameters and insulin resistance (HOMA-IR) were evaluated from fasting samples. The plasma total antioxidant status (TAS), total oxidant status (TOS), and serum paraoxonase activities were measured and then oxidative stress index (OSI) was calculated as the indicator of degree of oxidative stress. As the steatosis increased, the alanine aminotransferase, C-reactive protein, HOMA-IR, total cholesterol, and LDL cholesterol increased, whereas HDL cholesterol decreased. The TAS measurements were higher in the obese NAFLD group compared with that of the healthy control group. The TOS and OSI measurements did not differ between the groups. Paraoxonase activities increased significantly as steatosis increased. Among the children in this study, no relationship could be demonstrated between obesity with/without steatosis and oxidant/antioxidant status.

Paraoxonase activity and genetic polymorphisms in northern Han Chinese workers exposed to organophosphate pesticides

Paraoxonase (PON1) is one of the major players in the detoxification of organophosphates (OPs). This study presents our investigation into the effect of OPs on serum PON1 activity and the distribution of common PON1 polymorphisms in Han Chinese workers with repeated high exposure to OP pesticides, and the factors modulating PON1 activity. In all, 400 participants, including 180 workers exposed to OP pesticides occupationally, and 220 controls were investigated. Serum PON1 and cholinesterase (ChE) activity were measured, and genotyping was done using polymerase chain reaction-restriction fragment length polymorphism. The association between PON1 activity and PON1 polymorphisms, and the influencing factors of PON1 activity, were analyzed. The results revealed that repeated OP exposures significantly decreased serum PON1 and ChE activity (P< 0.05), although the exposed workers did not complain of health problems. Higher L and R allele frequencies for the L55M and Q192R polymorphisms of PON1 were observed. PON1 polymorphisms (especially the Q192R polymorphism) and pesticide exposures significantly affected serum PON1 activity in the study population. Therefore, the results of this investigation indicate PON1 polymorphisms and pesticide exposures may be important risk predictors for OP poisoning in the Han Chinese population, who display very high frequencies of the M allele and R allele for PON1 polymorphisms at the positions 55 and 192, respectively.

Relationship Between Serum Paraoxonase and Homocysteine Thiolactonase Activity, Adipokines, and Asymmetric Dimethyl Arginine Concentrations in Renal Transplant Patients

Paraoxonase lactonase activity protects against homocysteinylation; therefore, it can be a potential contributing factor to prevent atherosclerosis. We aimed to determine paraoxonase and HTLase activities and to clarify the relationship between HTLase activity and some cardiovascular risk factors, such as homocysteine, cystatin C asymmetric dimethylarginine (ADMA), and adipokines both in hemo dialyzed and transplanted patients. Among 114 hemodialyzed, 80 transplanted and 64 healthy control subjects, we investigated body mass index (BMI) as well as fasting serum contents of urea, uric acid, creatinine, cystatin C, homocysteine, glucose, lipids, total protein and albumin. Serum paraoxonase (PON 1) and HTLase activities were measured spectrophotometrically. ADMA, ADPN adiponectin, leptin (LEP) levels was determined with a sandwich enzyme-linked immunosorbent assay method. Dyslipidemic patients showed hypercholesterolemia, and high low-density lipoprotein (LDL); parallel with improved renal function, they displayed decreased cystatin C and homocysteine levels (P < .001). There was a significant negative correlation between PON 1 activity and cystatin C and homocysteine concentrations (P < .05). Obese patients revealed significantly higher LDL (P < .05) and leptin concentrations (P < .01). There was a significant positive correlation between PON 1 activity and adiponectin levels (P = .0276). Both dialyzed and transplanted patients displayed significantly lower HTLase activities compared to the control group (P < .001), particularly lower HTLase and PON 1 activities in dialyzed subjects compared with the transplanted group (P < .05). HTLase activity showed significant negative correlations with ADMA levels among the whole study population (P < .001), whereas positive associations were noted between PON 1 and HTLase activities (P < .001). HTLase activity may be a new predictor of cardiovascular risk in renal failure although it is modulated by other risk factors.

Multiple Myeloma: Relationship to Antioxidant Esterases

Objective: To investigate the status of the oxidant/antioxidant balance in patients with multiple myeloma compared to healthy controls. Materials and Methods: This study was conducted on 40 multiple myeloma patients and 40 healthy controls of matched age and sex. Serum total thiol, oxidative stress index (OSI), total oxidant status (TOS), and total antioxidant status (TAS) were measured using colourimetric methods; paraoxonase-1 and arylesterase enzyme activities were also quantified. Results: Serum paraoxonase-1 and arylesterase activities and total thiol levels were significantly lower (p = 0.0001, p = 0.036 and p < 0.0001, respectively), whereas TOS and OSI levels were significantly higher (p < 0.0001 for both parameters) in multiple myeloma patients compared to controls. However, no significant differences in TAS were identified when the two groups were compared. Conclusions: Our findings indicate an impaired oxidative/antioxidative balance in multiple myeloma. We recommend further studies with larger groups to investigate the possible relationship between oxidative stress and the aetiopathogenesis of multiple myeloma.

Serum Paraoxonase and Arylesterase Activities and Oxidative Stress Levels in Patients with SSRI Intoxication

Oxidative stress is a critical route of damage in various psychological stress-induced disorders, such as depression. Paraoxonase-1 (PON1) plays an important role as an endogenous free-radical scavenging molecule. The aim of this study was to evaluate the influence of serum PON1 activity and oxidative stress in patients with selective serotonin reuptake inhibitor (SSRI) intoxication. A total of 11 patients with SSRI intoxication and 20 healthy controls were enrolled. The serum total antioxidant capacity (TAC) and malondialdehyde (MDA) levels, as well as the paraoxonase and arylesterase activities, were measured spectrophotometrically. The serum TAC levels and the paraoxonase and arylesterase activities were significantly lower (for all, p<0.001), whereas the serum MDA levels were significantly higher in the patients with SSRI intoxication than in the controls (p<0.001). These results indicated that decreased PON1 activity and increased oxidative stress represent alternative mechanisms in SSRI toxicity. More studies are needed to elucidate the role of PON1 activity in the etiology of SSRI intoxication.

Decreased Serum Paraoxonase Activity in Patients With Chronic Pancreatitis

BackgroundRecent evidences suggest that oxidative stress is involved in the mechanism of chronic pancreatitis (CP). Paraoxonase 1 (PON1) plays an important role as an endogenous free-radical scavenging molecule. The aim of our study is to investigate whether serum PON1 activity is associated with the presence of CP. MethodsA total of 186 patients with alcoholic CP and 132 healthy subjects were enrolled in this study. Serum PON1 activity was measured using paraoxon as a substrate. ResultsSerum PON1 activity was significantly decreased in CP patients compared with healthy subjects. Multivariable logistic regression analysis revealed that serum PON1 activity was a determinant of the presence of CP (OR=0.992, 95% CI=0.987–0.998; P=0.006). ConclusionsDecreased serum PON1 activity may be considered as a predicting marker of the presence of CP.

Serum ferritin and paraoxonase-1 in canine leishmaniosis

Ferritin and paraoxonase-1 (PON-1) were measured in dogs experimentally infected by Leishmania infantum (during experimental infection and following treatment) and also in naturally-infected dogs which presented different degrees of proteinuria. Experimentally-infected dogs were monitored for 7 months post-infection, then treated for 3 months with allopurinol, and their response to therapy was followed for 11 additional months. Naturally-infected dogs were staged based on the urine protein/creatinine (UPC) ratio into three groups as follows: group 1 (non-proteinuric; UPC ratio: <0.2), group 2 (borderline proteinuric; UPC ratio: 0.2-0.5) and group 3 (proteinuric; UPC ratio>0.5). An increase in serum ferritin values and a decrease in PON-1 activity were observed 2 months after infection. Both analytes returned to preinfection values following treatment. Significantly higher concentrations of ferritin were observed in dogs classified as either borderline or proteinuric when compared with non-proteinuric dogs whereas serum PON-1 activity was decreased only in proteinuric dogs.

Assessment of early atherosclerotic findings in patients with nasal polyposis

To investigate early markers of atherosclerosis in patients with nasal polyposis (NP) through measurements of carotid artery intima-media thickness (CIMT), flow-mediated vasodilatation (FMD) of the brachial artery and serum paraoxonase-1 (PON-1) activity. Forty-five patients with NP were included in the study group and 45 healthy individuals in the control group. The diagnosis of patients with NP was predicated on anterior rhinoscopy, endoscopic nasal examination and coronal paranasal sinus computed tomography (CT). Measurements of CIMT and FMD of the brachial artery were performed by high-resolution ultrasonography. Serum PON-1 activity was evaluated by measuring the rate of paraoxon hydrolysis. Mean CIMT values were found to be increased in the NP group compared to the control group. However, mean FMD % values and serum PON-1 activity were significantly lower in the NP group compared to the control group. Moreover; the endoscopic polyps' scores and paranasal sinus CT scores were positively correlated with CIMT and negatively correlated with FMD % values and PON-1 activity. Disease duration also was positively correlated with CIMT and negatively correlated with FMD % values. Impaired FMD, increased CIMT and decreased serum PON-1 activity may be considered to be risk factors for accelerated atherosclerosis in patients with NP who may have subclinical atherosclerosis and be at risk for cardiovascular events in the future.

Paraoxonase and arylesterase activity and total oxidative/anti-oxidative status in patients with idiopathic Parkinson’s disease

This study investigated serum paraoxonase (PON1) and arylesterase activity along with determination of oxidative status via measurement of total oxidant status (TOS), total anti-oxidant status (TAS) and oxidative stress index (OSI) in patients with Parkinson’s disease (PD) and compared results with data from healthy controls. A total of 82 subjects, including 42 patients with idiopathic PD, newly diagnosed and untreated (24 men, 18 women, aged 47–66years) and 40 healthy controls were enrolled in this study. We aimed to evaluate the oxidative status of PD patients via measurement of serum TOS and TAS and estimation of OSI using new automated methods. PON1 and arylesterase activities were measured spectrophotometrically. Serum total cholesterol, high density lipoprotein cholesterol, low density lipoprotein (LDL) cholesterol and triglyceride levels were measured using routine methods. TAS levels of PD patients were significantly lower than that of controls (p<0.05). TOS levels of PD patients were higher than those of controls (p<0.05). PON1 and arylesterase activities of PD were lower than those of controls (p<0.05). Serum levels of total and LDL cholesterol were significantly reduced in PD patients. In conclusion, the presence of high TOS and OSI levels together with low levels of TAS in PD patients supports the important role of oxidative stress in the pathophysiology of PD. Since oxidative stress is involved in neurodegeneration, selecting anti-oxidants, metal chelators or other compounds boosting endogenous enzymatic and non-enzymatic defense mechanisms seems to be an obvious choice as treatment for PD.

Paraoxonase 1 and oxidative stress in paediatric non‐alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) in children is a significant public health concern. Oxidative stress is an important component in the pathophysiology of NASH. Several enzymatic antioxidant mechanisms protect the liver from oxidative injury. Examination of the expression of these enzymes in NASH livers may provide insight on the roles for these antioxidant mechanisms in the pathophysiology of NASH. The mRNA expression of catalase, glutathione peroxidase 1 (GPX1), glutathione reductase (GSR), paraoxonase 1 (PON1) and other reactive oxygen species-related genes was evaluated by microarray and quantitative real-time PCR analyses. The PON1 protein levels were evaluated in liver and serum by Western blot analyses. Serum enzymatic activities of GPX, GSR and PON1 (paraoxonase and arylesterase activities) were examined. NASH livers exhibited elevated mRNA expression of catalase and PON1, but not GPX1 or GSR. No difference in serum GPX or GSR activity was detected between NASH patients and controls. Elevated expression of PON1 mRNA and protein was detected in NASH livers, but serum PON1 protein and activities were not elevated. Elevated expression of catalase and PON1 suggests protective roles for these antioxidants in NASH livers. Given the importance of oxidative stress in the pathophysiology of NASH, future studies focusing on these enzymes could identify important targets for therapeutic or preventive interventions for NASH patients.

Impaired paraoxonase-1 status in obese children. Relationships with insulin resistance and metabolic syndrome

ObjectivesTo investigate the relationships between serum paraoxonase-1 (PON1), insulin resistance, and metabolic syndrome (MetS) in childhood obesity. Design and methodsWe studied 110 obese children and 36 non-obese children with a similar gender and age distribution. We measured serum PON1 activity against 5-thiobutyl butyrolactone (TBBLase) and against paraoxon (paraoxonase). PON1 concentration was measured separately as were the levels of several standard metabolic variables. The homeostasis model assessment (HOMA) index was calculated as an estimate of insulin resistance. ResultsTBBLase was significantly decreased in obese children (P=0.008), while paraoxonase activity and PON1 concentrations showed non-significant trends towards decrease and increase, respectively (P=0.054 and P=0.060). TBBLase and paraoxonase specific activities were significantly decreased (P=0.004 and P=0.018, respectively). TBBLase specific activity was inversely associated with BMI, percentage body fat, insulin, HOMA, triglycerides, and C-reactive protein, and directly associated with HDL-cholesterol. Paraoxonase specific activity showed similar associations with BMI, percentage fat, HDL-cholesterol, and C-reactive protein. Obese children with MetS had lower TBBLase activities than obese children without MetS (P=0.018). Linear regression analyses showed that TBBLase was independently associated with HDL-cholesterol, BMI, percentage body fat and PON155 polymorphism, but paraoxonase activity was associated only with PON1192 polymorphism. ConclusionsOur results suggest that PON1 may play a role in the onset and development of metabolic alterations in childhood obesity leading to diabetes and cardiovascular disease later in life. However, being derived from statistical association study, this finding cannot be seen as showing cause–effect.

Serum paraoxonase activity and lipid hydroperoxide levels in adult football players after three days football tournament

It has been suggested that physical activity is an important factor in the prevention and treatment of cardiovascular diseases. Low serum paraoxononase-1 (PON1) activity is with an associated risk of atherosclerotic disease. In this study, we aimed to investigate serum PON1 activity and lipid hydroperoxide (LOOH) levels in adult football players after three days football tournament. Twenty-three adult male football players and 23 sedentary male subjects after three days football tournament were enrolled. Serum paraoxonase, arylesterase activities and LOOH levels were determined. Serum paraoxonase and arylesterase activities were significantly higher in football players than sedentary subjects (all, p<0.05), while LOOH levels were significantly lower (p< 0.05). Serum LOOH levels were inversely correlated with paraoxonase and arylesterase activities (r=-0.552, p<0.001; r=-0.812, p<0.001; respectively) in adult football players. Our data show, for the first time, that physical activity is associated with increased PON1 activity and decreased oxidative stress after three days football tournament. In addition, physical activity for a healthy life is important in increasing serum PON1 activity, and this may play a role in the prevention of atherosclerosis.

Evaluation of systemic oxidant/antioxidant status and paraoxonase 1 enzyme activities in psoriatic patients treated by narrow band ultraviolet B phototherapy

ObjectivesUltraviolet B is a potent oxidative stress (OS) inducer in the skin; however, there are no data about the systemic oxidative effect of narrow band ultraviolet B (NB-UVB) phototherapy. In this study, we aimed to investigate the change in the OS status of psoriatic patients who were treated by NB-UVB phototherapy and to determine the relationships between OS, psoriasis severity, and systemic inflammatory condition.MethodsTwenty-four psoriatic patients were treated with a total of 30 sessions of NB-UVB irradiation. Psoriasis area and severity index (PASI), serum levels of high sensitive C-reactive protein (hsCRP), total antioxidant status (TAS), total oxidant status (TOS), the oxidative stress index (OSI), serum paraoxonase (PON), and arylesterase (ARE) activities before and after NB-UVB therapy were determined.ResultsPASI scores significantly decreased after NB-UVB therapy (P = 0.001). The pre- and post-treatment hsCRP and TAS levels were similar (P = 0.253 and 0.301, respectively). TOS and OSI values significantly increased after phototherapy (both P < 0.001). PON and ARE activities did not change after treatment (both P > 0.05). There was no correlation between PASI and hsCRP, TAS, TOS, OSI, PON, and ARE values (P > 0.05).ConclusionA systemic OS may emerge in psoriatic patients treated by NB-UVB phototherapy.

Paraoxonase-1 Is Associated With Corneal Endothelial Cell Alterations in Patients With Chronic Obstructive Pulmonary Disease

To investigate the relationships between the levels of the antioxidant enzyme paraoxonase-1 (PON1) and corneal endothelial alterations in patients with chronic obstructive pulmonary disease (COPD) undergoing cataract surgery. We studied 172 patients with cataract attending our ophthalmology clinic. Based on spirometric analysis, they were segregated into two groups, 110 (64%) with COPD and 62 (36%) without COPD. Corneal endothelial cell morphology was examined by widefield noncontact specular microscopy, which allows measurements of endothelial cell density (ECD), hexagonality, and endothelial cell size coefficient of variation (ECCV). Corneal thickness was measured by noncontact pachimetry. PON1 and plasma TNFα concentrations were analyzed by ELISA. Serum PON1 activity was analyzed by spectrophotometry. Patients with COPD had significant decreases in ECD, hexagonality, and corneal thickness, and a significant increase in ECCV. They also had significant decreases in serum PON1 activity but not in PON1 concentration. Serum PON1 activity showed a significant direct association with ECD, and an inverse association with corneal thickness. Results of the present study suggest that PON1 may be involved in the pathophysiology of corneal endothelial alterations in patients with COPD.

Correlation between Cholinesterase and Paraoxonase 1 Activities:Case Series of Pesticide Poisoning Subjects.

Acute exposure to pesticide due to suicidal poisoning is the most extensive cause of pesticide exposure, compared with all other causes including agricultural or industrial exposure. Organophosphate (OP) and carbamate group of pesticides can inhibit acetylcholinesterase; on the other hand, paraoxonase1 can detoxify organophosphate poisoning by hydrolyzing organophosphate metabolites. We have compared the serum paraoxonase1 status and cholinesterase activity of subjects who attempted to commit suicide by consuming OP pesticide. Cholinesterase and paraoxonase1 activity were measured spectrophotometrically using butyrylthiocholine and phenyl acetate as substrates, respectively. A positive correlation was found between serum paraoxonase1 activity and cholinesterase activity among pesticide consumed subjects. Our results suggest that subjects with higher paraoxonase1 activity may have a better chance of detoxifying the lethal effect of acute organophosphate poisoning.

Serum paraoxonase 1 activity in dogs: preanalytical and analytical factors and correlation with C‐reactive protein and alpha‐2‐globulin

Serum activity of paraoxonase (PON1) decreases during inflammation in many species. Little information is available on paraoxon-based tests and the possible role of PON1 in dogs. The objectives of the study were to validate an automated paraoxon-based assay to measure PON1 activity in canine serum, to determine its stability under different storage conditions, to determine a reference interval (RI) in healthy dogs, and to assess whether PON1 is of comparable diagnostic value as C-reactive protein (CRP) and α2-globulins. Intra-assay and inter-assay imprecision, linearity under dilution (LUD), interference, and storage artifacts were evaluated. A PON1 RI was determined for healthy dogs, and PON1 activity, sensitivity, and specificity were compared with CRP and α2-globulins. Intra- and inter-assay CVs were below 1.6% and 7.8%, respectively. The LUD test fitted the linear model. PON1 activity measurements were increased after addition of hemolysates and lipids, and after storage for 12 hours at room temperature, 72 hours at 4°C, and 6 months at -20°C. PON1 activity and CRP or α2-globulins did not correlate well. PON1 activity decreased significantly only in dogs with very high CRP concentrations. In contrast to CRP and α2-globulins, PON1 activity was not significantly different between dogs with and without inflammation. The automated paraoxon-based method to assess serum canine PON1 activity was accurate and precise, but it was influenced by hemolysis, lipemia, and standard storage conditions. In this study, contrarily to CRP and α2-globulins, PON1 activity did not provide diagnostic value as a negative acute phase protein in dogs.

Hypothyroidism and Oxidative Stress: Differential Effect on the Heart of Virgin and Pregnant Rats

The present study investigates the effects of hypothyroidism on both the redox state and the thyroid hormone receptors expression in the heart ventricle of virgin and pregnant rats.Hypothyroid state was induced by 6-n-propyl-2-thiouracil in drinking water given to Wistar rats starting 8 days before mating until day 21 of pregnancy or for 30 days in virgin rats. Serum paraoxonase-1 (PON-1) activity, serum and heart nitrites, and thiobarbituric acid-reactive substances (TBARS) were analyzed. Heart protein oxidation, as carbonyls, and copper-zinc superoxide dismutase (CuZnSOD), glutathione peroxidase (GPx), and catalase (CAT) activities, were determined. In addition, heart expressions of NADPH oxidase (NOX-2), CAT, SOD, GPx, and thyroid receptors (TRα and TRβ) mRNA were assessed by RT-PCR. Inducible and endothelial Nitric Oxide Synthase (iNOS and eNOS) were determined by Western blot. Hypothyroidism in the heart of virgin rats decreased TRα and TRβ expressions, and induced oxidative stress, leading to a decrease of nitrites and an increase of carbonyls, NOX-2 mRNA, and GPx activity. A decreased PON-1 activity suggested low protection against oxidative stress in blood circulation. Pregnancy reduced TRα and TRβ mRNA expressions and induced oxidative stress by increasing nitrite and TBARS levels, SOD and CAT activities and NOX-2, eNOS and iNOS expressions, while hypothyroidism, emphasized the decreases of TRα mRNA levels and did not alter the redox state in the heart. TR expressions and redox balance of rat hearts depend on the physiological state. Pregnancy per se seems to protect the heart against oxidative stress induced by hypothyroidism. Supporting Information for this article is available online at http://www.thieme-connect.de/ejournals/toc/hmr.

Paraoxonase-1 activity and oxidative stress markers in anterior ST elevation myocardial infarction with and without no-reflow undergoing primary percutaneous coronary intervention

Background: Reperfusion injury is one of the pathogenetic mechanisms of no-reflow. We aimed to investigate the relationship between no-reflow with paraoxonase activity and oxidative stress markers (total antioxidant status (TAS), total oxidant status (TOS), lipid hydro-peroxide (LOOH)) in patients with anterior ST elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Methods: In this study, 215 consecutive anterior STEMI patients undergoing primary PCI were prospectively included (177 male, 38 female; mean age 54.9±12.0 years). No-reflow was defined as TIMI grade 0 and 1 flows or TIMI grade 3 with myocardial blush grade 0 and 1. The patients were divided into two groups as normal flow (n=179) and no-reflow (n=36) groups. Serum paraoxonase activity was measured spectrophotometrically. TAS and TOS levels were determined by using an automated measurement method. LOOH levels were measured by ferrous oxidation with xylenol orange assay. Results: Patients with no-reflow was older and had higher incidence of female gender, hypertension and diabetes. Patients with no-reflow was also had higher infarction time, higher thrombus score and SYNTAX score. Paraoxonase activities and TAS levels were significantly lower and TOS and LOOH levels were significantly higher in patients with no-reflow compared to normal flow group. On multivariate logistic regression analysis, paraoxonase activity (β=0.975, %CI=0.957-0.994, p=0.009) and TOS (β=1.142, %CI=1.058-1.233, p=0.001) as well as diabetes, infarction time, thrombus score and SYNTAX score were independent predictors of no-reflow (Table 1). View this table: Table 1 Conclusion: In patients with no-reflow, oxidants are increased, while serum paraoxonase-1 activity and antioxidants are decreased. This result shows that increased oxidative stress may have role in the pathogenesis of no-reflow.