Advanced Oxidation Protein Products Concentrations Research Articles

The influence of the occupational exposure to heavy metals and tobacco smoke on the selected oxidative stress markers in smelters.

The aim of the study was to verify if there is any association between exposure to Cu, Zn, Cd, Pb, As and the formation of malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), advanced oxidation protein products (AOPP), and whether in this process cigarette smoking plays a role. The investigations were performed in the 352 smelters occupationally exposed to heavy metals and 73 persons of control group. Metals concentration was determined by atomic absorption spectrometry. MDA and AOPP concentrations were determined by spectrophotometric methods. The concentration of 8-OHdG was determined by ELISA method. It was demonstrated an increased Cu concentration in smoking smelters compared to non-smoking control group. It was noted no differences in Zn and Mg concentrations between the examined groups. Pb concentration was more than sixfold higher in the group of smoking smelters and about fivefold higher in the group of non-smoking smelters compared to the control groups (smokers and non-smokers). It was shown that Cd concentration in the blood was nearly fivefold higher in the smoking control group compared to the non-smoking control group and more than threefold higher in the group of smoking smelters compared to non-smoking. It was shown an increased As concentration (more than fourfold) and decreased Ca concentration in both groups of smelters compared to control groups. In groups of smelters (smokers and non-smokers), twofold higher MDA and AOPP concentrations, and AOPP/albumin index compared to control groups (smokers and non-smokers) were shown. Tobacco smoke is the major source of Cd in the blood of smelters. Occupational exposure causes accumulation of Pb in the blood. Occupational exposure to heavy metals causes raise of MDA concentration and causes greater increase in AOPP concentration than tobacco smoke.

Lipid and protein oxidation in newborn infants after lutein administration.

Objectives. To test the hypothesis that neonatal supplementation with lutein in the first hours of life reduces neonatal oxidative stress (OS) in the immediate postpartum period. Methods. A randomized controlled, double-blinded clinical trial was conducted among 150 newborns divided into control group, not supplemented (n = 47), and test group, supplemented with lutein on the first day postpartum (n = 103). Blood Samples were collected at birth from cord and at 48 hrs postpartum while routine neonatal metabolic screenings were taking place. Total hydroperoxide (TH), advanced oxidation protein products (AOPP), and biological antioxidant potential (BAP) were measured by spectrophotometry and data were analyzed by Wilcoxon rank sum test and by multivariate logistic regression analysis. Results. Before lutein supplementation, the mean blood concentrations of AOPP, TH, and BAP were 36.10 umol/L, 156.75 mmol/H2O2, and 2361.04 umol/L in the test group. After lutein supplementation, significantly higher BAP increment (0.17 ± 0.22 versus 0.06 versus ± 0.46) and lower TH increment (0.46 ± 0.54 versus 0.34 ± 0.52) were observed in the test group compared to controls. Conclusion. Neonatal supplementation with lutein in the first hours of life increases BAP and reduces TH in supplemented babies compared to those untreated. The generation of free radical-induced damage at birth is reduced by lutein. This trial is registered with ClinicalTrials.gov NCT02068807.

Total antioxidant status and markers of oxidative stress in subjects with normal or impaired glucose regulation (IFG, IGT) in diabetic patients

Background. We investigated the ischemia-modified albumin (IMA), advanced oxidation protein products (AOPPs), prooxidants–antioxidants balance (PAB), and ferric reducing antioxidant power (FRAP) concentrations in patients with impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and diabetes mellitus (DM) and compared the results to those of normoglycemic individuals at baseline and 2 hours after glucose loading. Methods. An oral glucose tolerance test was performed on age-matched subjects (n = 110) with a body mass index (BMI) < 27 kg/m2. Subjects were categorized as normoglycemic (n = 35), IFG (n = 25), IGT (n = 30) and DM (n = 20) according to the WHO criteria. The IMA, AOPP, PAB, FRAP concentrations were determined by colorimetric methods. Results. At baseline, the AOPP concentrations were significantly higher in subjects with IFG and DM compared to normoglycemic subjects (p < 0.01 for all cases). The IFG, IGT and DM patients had a significantly higher IMA at baseline when compared with the normoglycemic individuals (p < 0.001 for all cases). The IMA in IFG subjects was significantly elevated (p < 0.05), while in DM patients, the IMA was significantly decreased (p < 0.001) after glucose loading with respect to baseline concentrations. Following glucose loading, the PAB was significantly decreased from baseline concentrations in normoglycemic individuals (p < 0.001) and in the IFG (p < 0.001) and IGT (p < 0.001) patients. Conclusion. In subjects with impaired glucose metabolism, the hyperglycemia is associated with increased IMA, AOPP and PAB concentrations. Increased IMA in subjects with IFG and decreased FRAP concentrations in subjects with IGT after glucose loading suggests that an increase in glucose concentrations can lead to tissue damage by increasing oxidative stress.

Advanced oxidation protein products enhances soluble Fms-like tyrosine kinase 1 expression in trophoblasts: A possible link between oxidative stress and preeclampsia

Accumulation of advanced oxidation protein products (AOPPs) is prevalent in obesity, advanced maternal age, diabetes mellitus, and polycystic ovary syndrome. Alterations in the regulation and signaling of angiogenic pathways have been recognized as a link between these conditions and pre-eclampsia. To investigate the possible impact of AOPPs on soluble Fms-like tyrosine kinase 1 (sFlt-1) expression in trophoblasts. A trophoblast cell line (HRT-8/SVneo) was treated with various concentrations of AOPPs. The mRNA expression of sFlt-1, vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) in trophoblasts were measured with the use of real-time polymerase chain reaction; and the secretion of sFlt-1, VEGF, and PlGF protein from trophoblasts were detected with the use of ELISA. Exposure of HRT-8/SVneo cells to AOPPs induced overexpression of sFlt-1 at mRNA and protein levels in a dose dependent manner. These effects could be inhibited by apocynin, an inhibitors of NADPH oxidase. Our data identified AOPPs as a class of important mediator in the regulation and signaling of angiogenic pathways of trophoblasts. Accumulation of AOPPs might contributes to the pathogenesis of preeclampsia by promoting sFlt-1 production in trophoblasts.

Serum levels of LH, FSH, estradiol and progesterone in female rats experimentally infected by Trypanosoma evansi

The goal of this study was to evaluate reproductive hormones in sera samples of female rats experimentally infected by Trypanosoma evansi during different phases of the estrous cycle. For that, 64 animals were divided into two groups: 24 rats for the control group (uninfected), and 40 animals were infected by T. evansi. These groups were divided into subgroups according to the time of infection (days 5 and 15 post-infection; PI) and the phase of the estrous cycle (proestrus, estrus, metestrus and diestrus). Serum was collected at days 5 and 15 PI and the levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone and estradiol were assessed by enzyme immunoassay technique. The concentration of nitrite/nitrate (NOx), advanced oxidation protein products (AOPP), and thiobarbituric acid reactive substances (TBARS) were measured in ovaries and uteruses in these same periods. Infected females showed significant decrease (P<0.05) of LH, FSH, estradiol and progesterone in different periods and phases of the estrous cycle when compared to uninfected rats. In addition, it was observed an increase in the concentration of NOx, AOPP, and TBARS in the ovaries, which is indicative of cell damage. Therefore, our experimental study showed that T. evansi infection in female rats may cause changes in LH, FSH, estradiol, and progesterone levels regardless of the time of infection or phase of the estrous cycle.

Advanced oxidation protein products in acute pancreatitis

Background: Understudied part of acute pancreatitis is evaluating the significance of activation of lipid and protein deficiency and inadequate antioxidant system. The focus was on determining the concentration of advanced oxidation protein products (AOPP) in patients with acute pancreatitis, depending on the severity and duration of disease. Material and Methods: Level of AOPP determined in dynamics in 53 patients with acute pancreatitis of different severity (25 – with mild and 28 – with severe pancreatitis). The control group comprised 14 volunteers. AOPP concentration in plasma was determined by photometric assay. Results: In severe acute pancreatitis patients concentration of AOPP increased in plasma. This correlates with the level of hydrogen peroxide. Sensitivity determination of AOPP to predict severe acute pancreatitis was 96,4%, specificity – 100%. A significant direct correlation between the concentration of AOPP and the level of creatinine, glucose, and C-reactive protein in serum was established. Conclusion: In acute pancreatitis observed intensive oxidation proteins processes that play an important role in the pathogenesis of the disease. AOPP can be a potential marker of the severity of acute pancreatitis.

Oxidative stress and inflammatory markers are associated with depression and nicotine dependence

To determine if oxidative stress and inflammation are linked with major depressive disorder, nicotine dependence and both disorders combined. This study comprised 150 smokers and 191 never smokers. The instruments were: a socio-demographic questionnaire, diagnoses of mood disorder and nicotine dependence according to DSM-IV, (SCID-IV), and the Alcohol, Smoking and Substance Involvement Screening Test. Laboratory assessments included: nitric oxide metabolites (NOx), lipid hydroperoxides, malondialdehyde (MDA), total reactive antioxidant potential (TRAP), advanced oxidation protein products (AOPP), fibrinogen concentrations, homocysteine, erythrocytes sedimentation rate (ESR) and high-sensitivity C-reactive protein (hs-CRP) were assayed from blood specimens. Statistically significant differences were found among depressed smokers who had more severe depressive symptoms, a higher risk of alcohol consumption, more suicide attempts, and more disability for work than non-depressed never smokers. Depressed smokers had significantly higher levels of NOx, fibrinogen, hs-CRP, AOPP, ESR and lower levels of TRAP compared to non-depressed never smokers. Depressed smokers had significant levels of oxidative stress and inflammatory biomarkers after adjusting for gender, age, years of education, disability for work, and laboratory measures. The levels of NOx, lipid hydroperoxides, AOPP, and fibrinogen were substantially higher, whereas levels of TRAP were lower in depressed smokers compared to non-depressed never smokers. (1) Depressed smokers exhibited altered concentrations of NOx, lipid hydroperoxides, AOPP, TRAP, and fibrinogen. (2) Depressed smokers were more unable to work, showed more severe depressive symptoms and attempted suicide more frequently.

Assessment of Oxidative, Inflammatory, and Fibrinolytic Biomarkers and DNA Strand Breakage in Hypercholesterolemia

The aim of this study was to assess the levels of oxidative, inflammatory, and fibrinolytic biomarkers as well as DNA strand breakage in hypercholesterolemic subjects. Fasting glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, total protein, albumin, apolipoprotein (Apo) A, Apo B, advanced oxidation protein products (AOPP), increased ischemia-modified albumin (IMA), -SH, NOx, IL-6, and D-dimer levels were assessed, and DNA strand breakage was evaluated using comet assay in 38 patients with hypercholesterolemia and 20 healthy controls. Total cholesterol, triglycerides, LDL cholesterol, Apo A, Apo B, AOPP, IMA, IL-6, and D-dimer concentrations were significantly higher in subjects with hypercholesterolemia. However, NOx and plasma -SH group concentrations were lower in hypercholesterolemic subjects, while no significant differences were observed with respect to DNA strand breakage between the two groups. Hypercholesterolemia is related to oxidative stress and inflammation. Accordingly, AOPP concentration was higher in subjects with hypercholesterolemia, and we speculate that AOPP can reflect the enhancement of protein oxidation and inflammation.

Sorafenib-Induced Hepatocellular Carcinoma Cell Death Depends on Reactive Oxygen Species ProductionIn VitroandIn Vivo

Sorafenib is presently the only effective therapy in advanced hepatocellular carcinoma (HCC). Because most anticancer drugs act, at least in part, through the generation of reactive oxygen species, we investigated whether sorafenib can induce an oxidative stress. The effects of sorafenib on intracellular ROS production and cell death were assessed in vitro in human (HepG2) and murine (Hepa 1.6) HCC cell lines and human endothelial cells (HUVEC) as controls. In addition, 26 sera from HCC patients treated by sorafenib were analyzed for serum levels of advanced oxidation protein products (AOPP). Sorafenib significantly and dose-dependently enhanced in vitro ROS production by HCC cells. The SOD mimic MnTBAP decreased sorafenib-induced lysis of HepG2 cells by 20% and of Hepa 1.6 cells by 75% compared with HCC cells treated with 5 mg/L sorafenib alone. MnTBAP significantly enhanced by 25% tumor growth in mice treated by sorafenib. On the other hand, serum levels of AOPP were higher in HCC patients treated by sorafenib than in sera collected before treatment (P < 0.001). An increase in serum AOPP concentration ≥0.2 μmol/L chloramine T equivalent after 15 days of treatment is a predictive factor for sorafenib response with higher progression free survival (P < 0.05) and overall survival rates (P < 0.05). As a conclusion, sorafenib dose-dependently induces the generation of ROS in tumor cells in vitro and in vivo. The sera of Sorafenib-treated HCC patients contain increased AOPP levels that are correlated with the clinical effectiveness of sorafenib and can be used as a marker of effectiveness of the drug. .

Yerba Mate (Ilex paraguarensis) as a novel feed supplement for growing lambs

Yerba Mate (Ilex paraguarensis), a plant known for its high antioxidant content, was fed to 20 of 40 lambs for 8 weeks. Lambs were randomly divided into two groups: one group (n=20) was fed the control diet and one group (n=20) was fed the control diet with 2.5% Yerba Mate. Lambs were group housed by treatment and fed ad libitum through automatic feeders that recorded individual food intake. Lambs received the dietary treatments for a total of 8 weeks and were monitored for live weight (LW), average daily growth rate (ADG), food conversion rate (FCR) and feed intake. Blood samples (8mL) were taken from all lambs, on weeks 0, 2, 4, 6, and 8 and plasma analysed for total antioxidant capacity (TAC), advanced oxidation protein products (AOPP), non-esterified fatty acids (NEFA), triglycerides and cholesterol. Wool growth and cell-mediated immune status (PHA) were also measured. Overall, Yerba Mate (YM) lambs ate more (mean±sem; 989±68g/d; P<0.001) pellet than the control (CTRL) lambs (759±63g/d), however, LW (YM: 33.5±1.1kg and CTRL: 33.5±1.2kg) and ADG (YM: 207±9.6g/day and CTRL: 191±8.4g/day) were not significantly different between the two groups. FCR (g VFI/g ADG) was higher (P<0.05) in the Yerba Mate supplemented lambs compared to the control ones (4.78±0.45 and 3.97±0.32, respectively). Wool growth rate was higher (P<0.01) in the YM lambs (0.09±0.005g/cm2 and 0.07±0.005g/cm2, respectively). There was a significant effect of the interaction diet×sampling time on plasma AOPP concentrations (P<0.05), with Yerba Mate lambs presenting higher AOPP levels than the control lambs on weeks 4 and 5. Overall, plasma NEFA and triglycerides concentrations were similar in the Yerba Mate and in the supplemented group (NEFA: 0.15±0.02 mmol/l and 0.17±0.02mmol/l, and triglycerides: 0.27±0.02mmol/l and 0.29±0.02mmol/l, respectively), however, a significant effect of the interaction time of sampling×diet on both metabolites (P<0.05) was noted, with Yerba Mate supplemented lambs presenting lower NEFA and triglycerides levels than the control lambs on weeks 3, 4, 5 and 6 and on weeks 3, 4 and 5. No significant effect of diet was noted for PHA test, cholesterol and TAC levels, fat depth, eye muscle depth and muscle score. Our study indicates that although Yerba Mate supplementation can increase feed intake and wool growth in lambs, it did not result in significant differences in LW, ADG or body composition and had a significant negative effect on FCR. Further work is required to investigate the effect of Yerba Mate supplementation on lambs production and health.

Age- and gender-related alteration in plasma advanced oxidation protein products (AOPP) and glycosaminoglycan (GAG) concentrations in physiological ageing

The authors studied the role of increased oxidative stress in the development of oxidative protein damage and extracellular matrix (ECM) components in ageing. The age- and gender-associated disturbances in connective tissue metabolism were evaluated by the plasma chondroitin sulphated glycosaminoglycans (CS-GAG) and non-sulphated GAG-hyaluronan (HA) measurements. Plasma concentration of advanced oxidation protein products (AOPP) was analysed in order to assess oxidative protein damage and evaluate the possible deleterious role of oxidative phenomenon on tissue proteoglycans' metabolism during the physiological ageing process. Sulphated and non-sulphated GAGs as well as AOPP were quantified in plasma samples from 177 healthy volunteers. A linear age-related decline of plasma CS-GAG level was found in this study (r=-0.46; p<0.05). In contrast, HA concentrations rise gradually with age (r=0.44; p<0.05) in plasma samples. For both ECM components, the observed differences were not gender-specific. A strong age-dependent relationship has been shown in regard to AOPP. AOPP levels significantly increased with age (r=0.63; p<0.05), equally strongly in both men (r=0.69; p<0.05) and women (r=0.57; p<0.05) during physiological ageing. A significant correlation was found between the concentrations of AOPP and both CS-GAG (r=-0.31; p<0.05) and HA (r=0.33; p<0.05). Proceeding with age changes in the ECM are reflected by CS-GAG and HA plasma levels. Strong correlations between AOPP and ECM components indicate that oxidative stress targets protein and non-protein components of the connective tissue matrix during human ageing.

Monitoring oxidative stress in acute‐on‐chronic liver failure by advanced oxidation protein products

Increased oxidative stress is important in the pathogenesis of acute-on-chronic liver failure (ACLF). This study aimed to investigate whether advanced oxidation protein products (AOPP) levels can monitor oxidative stress of ACLF patients. Furthermore, we aimed to study plasma exchange (PE) treatment and determine whether it can eliminate AOPP. We measured AOPP levels in 50 ACLF patients, 30 patients with compensated liver cirrhosis (CR), 30 patients with chronic hepatitis B (CHB) and 50 healthy controls by spectrophotometric assay. AOPP concentrations were also measured before and after PE treatment in ACLF patients. As an apoptosis marker, serum cytokeratin 18 (CK18 M 30) levels were detected to investigate the relationship between AOPP and apoptosis in ACLF patients. Significantly higher AOPP levels at admission were found in patients with ACLF compared with CR, CHB and healthy controls (69.45 ± 29.04 µmol/L vs. 19.67 ± 7.02 µmol/L, 26.75 ± 5.21 µmol/L and 21.35 ± 6.15 µmol/L, respectively; P < 0.001). There was a positive relationship with total bilirubin, Child-Pugh, model for end-stage liver disease scores and CK18 M 30. In ACLF patients, AOPP levels were higher in non-survivors than survivors. An AOPP cut-off of 74.21 µmol/L was used for predicting poor prognosis. Multivariate Cox regression analysis demonstrated that AOPP were independent risk factors for prognosis. Dynamic change of AOPP levels associated with prognosis appeared earlier than total bilirubin. Following PE treatment, AOPP levels reduced to 34.65 ± 18.14 µmol/L (P < 0.001). Advanced oxidation protein products were suitable for monitoring the levels of oxidative stress in ACLF patients. Increased AOPP may serve as an important biological marker of worse outcome. In addition, PE therapy was effective in reducing AOPP.

Protein Oxidative Stress and Dyslipidemia in Dialysis Patients

Our aim was to investigate and determine the associations between oxidative stress (OS), dyslipidemia and inflammation in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) using observational cross-sectional study. Twenty patients in CAPD and 48 in HD for at least 8 weeks and aged ≥18 years were included in the study. Individuals with malignant or acute inflammatory disease were excluded. A control group of 17 healthy individuals was also recruited. The biochemical parameter evaluations were analyzed using colorimetric kits for albumin, serum glucose, total cholesterol (TC) and lipid fractions. To determine the inflammatory status, CRP, IL-6 and TNF-α were analyzed by automated chemiluminescence kits. Plasma advanced oxidation protein products (AOPP) were determined by spectrophotometry. Mean AOPP levels were significantly higher for the HD group compared to the control, and there was no difference in AOPP concentrations between the control and CAPD groups. Dialysis patients had levels of inflammatory parameters higher than controls, and showed a high prevalence of patients with dyslipidemia, especially in CAPD. In the HD group, AOPP was positively correlated with triglycerides (TG) and inversely associated with HDL. Also the HD group was observed to have negative associations between TNF-α and HDL, LDL and TC. In the CAPD group, CRP was inversely correlated with HDL. Hemodialysis patients had increased protein OS and associations of inflammation and dyslipidemia were also observed in these dialysis groups. A more detailed characterization of the relations between oxidative stress and other more traditional risk factors has therapeutic importance, since cardiovascular diseases are the leading cause of death among dialysis patients.

Painful Procedures Produce Oxidative Stress in Newborns

Stressful events can damage neonatal brain through a complexity of events including free radical (FR) generation. We examined whether pain provoked by a routine heel prick can generate an increase in potentially harmful FR in neonatal blood. To this aim, advanced oxidation protein products (AOPP) and total hydroperoxide (TH) concentrations were measured at the beginning (sample A) and at the end (sample B) of each sampling in 109 babies (corrected age: 37.4+/−2.5 weeks) who underwent heel prick for routine blood tests. We scored pain of every procedure in all newborns. No differences were detected between AOPP and TH blood concentrations at the beginning and at the end of heel prick sampling, considering the whole cohort of babies. Conversely, a significant increase was observed between AOPP and TH blood concentrations considering only those babies who showed the highest pain intensity. When babies' pain was high (ABC score >or=4), mean AOPP and TH blood levels increased significantly; in this case, mean AOPP values increased from 54.9 microm/l (SD=41.63) to 61.5 microm/l (SD=44.08) and TH values from 220.71 UCarr (SD=83.72) to 230.87 UCarr (SD=89.5), with a significant p value of 0.03 and 0.02, respectively. These data show that even common routine procedures can be potentially harmful for the newborn if they provoke a high level of pain.

Advanced oxidation protein products and inflammatory markers in liver cirrhosis: a comparison between alcohol-related and HCV-related cirrhosis.

Advanced oxidation protein products (AOPPs) are protein markers of oxidative stress with pro-inflammatory properties that accumulated in liver cirrhosis. In the present study, we investigated the association between chronic inflammatory response triggered by AOPPs and the severity of liver disease as assessed by the Child-Pugh score. Plasma concentrations of AOPPs and inflammatory markers such as C-reactive protein, tumor necrosis factor-α, and interleukin-6 were measured in 41 patients with HCV-related cirrhosis, 43 patients with alcohol-related liver cirrhosis (ALC), and in 30 age and sex matched controls. In comparison with controls, AOPPs were increased in HCV-related compensated (Child-Pugh A) and decompensated (Child-Pugh B-C) cirrhosis and in alcohol-related compensated cirrhosis. AOPPs level positively correlated with Child-Pugh score in alcohol-related cirrhosis but not in HCV-related cirrhosis and the correlation with the indices of chronic inflammation was stronger in ALC. In turn, AOPPs in HCV-related cirrhosis was related to inflammation to a lesser extent, but a significant correlation with antioxidant defense could be noted. In summary, liver cirrhosis was associated with increased formation of AOPPs, which differed between alcohol-related and HCV-related cirrhosis with respect to the relationship between AOPPs and antioxidant defense, stage of liver cirrhosis, and inflammatory response. The significant correlation between AOPPs accumulation and indices of chronic inflammation, more specifically TNF-α, suggests that oxidative stress may be a mediator of chronic inflammatory state in the early stage of alcohol-related cirrhosis.

P02-40 - Antidepressant treatment and advanced oxidation protein products in depressed patients

IntroductionOxidative stress plays a role in producing advanced oxidation protein products (AOPP). High level of AOPP was observed in patients with such pathological conditions as ischemic heart disease, diabetes, cancer or neurodegenerative diseases.ObjectivesA role of oxidative stress in depression and in antidepressant treatment has been implicated. There have been no studies so far on AOPP in psychiatric diseases.Aim: An assessment of AOPP concentration, as a marker of oxidative stress, in patients with depression and the effect of antidepressant treatment.MethodsThirty-one patients hospitalized at Department of Adult Psychiatry, Poznan University of Medical Sciences, were studied. The first depressive episode was diagnosed in 5 patients, recurrent depressive disorder in 6 patients, and depression in the course of bipolar affective disorder in 20 patients. Patients were treated with venlafaxine (10), paroxetine (7), fluoxetine (5), clomipramine (4), citalopram (3), sertraline (1) and mianserine (1). Advanced oxidation protein products (AOPP) levels were measured twice: before treatment and in remission on maintenance doses of drugs. Control group consisted of 18 healthy volunteers, age- and gender matched.ResultsThere was no significant difference between depressed patients and healthy controls in the AOPP concentration before treatment. There was no correlation between AOPP levels and diagnosis, duration of illness, duration of the current episode and the age of illness’ onset. After antidepressant treatment, a significant decrease of AOPP concentration was found.ConclusionsThe results of the study may confirm previous data suggesting a decrease of some markers of oxidative stress after antidepressant treatment.

Expressions of Protein Oxidation Markers, Dityrosine and Advanced Oxidation Protein Products in Acetaminophen-Induced Liver Injury in Rats

The purpose of this study was to evaluate whether dityrosine and advanced oxidation protein products (AOPP) were useful as biomarkers for monitoring the development of acetaminophen-induced liver injury. Dityrosine immunoexpression in the liver along with plasma AOPP concentration was examined up to 24 hr post-acetaminophen injection in rats. The histopathological changes in the liver appeared 3 hr after acetaminophen injection and became exacerbated with time. The immunohistological expression of dityrosine was also first detected in the damaged hepatocytes 3 hr after the injection and became more accentuated at 6, 12 and 24 hr in accompanying with the elevation of plasma AOPP concentration. These results suggested that dityrosine and AOPP expressions might be useful biomarkers for monitoring the development of acetaminophen-induced liver injury.

Expressions of Protein Oxidation Markers, Dityrosine and Advanced Oxidation Protein Products in Cisplatin-Induced Nephrotoxicity in Rats

The purpose of this study was to evaluate whether dityrosine and advanced oxidation protein products (AOPP) reflect the severity of cisplatin-induced nephrotoxicity. Immunoexpression of dityrosine in kidneys and plasma AOPP concentration were examined up to day 4 post-cisplatin injection in rats. Cisplatin injection induced tubular injury on days 2-4 after injection and increased serum creatinine and BUN on days 3 and 4. On days 2-4, dityrosine was immunostained in the cytoplasm of damaged tubular cells, and their immunostaining intensity increased time-dependently. Plasma AOPP levels were significantly increased on days 3 and 4. These results suggest that expressions of dityrosine and AOPP were associated with the severity of renal injury and may be useful markers for the development of cisplatin-induced nephrotoxicity.

Prolonged pain to hospital time is associated with increased plasma advanced oxidation protein products and poor prognosis in patients with percutaneous coronary intervention for ST-elevation myocardial infarction

Plasma advanced oxidation protein products (AOPP) are a biomarker for increased production of reactive oxygen species. We examined the possible association between pain to hospital time, plasma AOPP, and outcome of patients receiving percutaneous coronary intervention (PCI) for ST-elevation acute myocardial infarction (STEMI). Plasma AOPP was determined at hospitalization as well as 24 and 48 h after PCI in 79 patients with suspected STEMI. Patients were stratified into a control group (Group I, n = 21) after exclusion of coronary artery disease, Group II (n = 46) with pain to hospital time <12 h, and Group III (n = 33) with pain to hospital time >12 h. Associations between pain to hospital time and AOPP as well as incidence of major adverse cardiac events (MACE) during 6 months of follow-up were analyzed. Plasma AOPP at admission was significantly higher in patients of Group II (97.58 +/- 23.41 micromol/l) and Group III (184.52 +/- 30.41 micromol/l) in comparison with Group I (57.41 +/- 13.60 micromol/l, all P < 0.001). Plasma AOPP concentration was positively correlated with pain to hospital time and associated with an increased incidence of MACE during the 6-month follow-up period. Prolonged ischemia is associated with increased oxidative stress and poor prognosis in patients treated with PCI for STEMI.

Oxidative stress and arterial stiffness in strength- and endurance-trained athletes

Background Endurance exercise training decreases arterial stiffness, whereas high-intensity strength exercise training increases arterial stiffness. However, the mechanisms underlying the adaptations to the 2 types of exercise training remain unclear. Increased oxidative stress induces vasoconstriction and endothelial dysfunction. Plasma advanced oxidation protein products (AOPP)—a novel marker of oxidative stress—have recently been reported to be positively associated with arterial stiffness in healthy subjects. We hypothesized that AOPP are involved in the adaptation of arterial stiffness in different types of exercise training. Methods We investigated plasma AOPP concentration and arterial stiffness in strength- and endurance-trained athletes. The subjects included young strength-trained athletes (SA group) (shot put, hammer, or javelin throwers; n = 12), endurance-trained athletes (EA group) (long- or middle-distance runners; n = 10), and sedentary individuals (Control group) ( n = 12). We measured aortic pulse-wave velocity (PWV), systemic arterial compliance (SAC), and plasma AOPP concentrations. Results PWV was higher in the SA than in the EA or control groups (SA: 6.48 ± 0.47, EA: 6.00 ± 0.67, Control: 5.65 ± 0.52 m/s, mean ± SD), and SAC was lower in the SA than in the EA or control groups (SA: 1.04 ± 0.24, EA: 1.56 ± 0.44, Control: 1.38 ± 0.35 ml/mmHg); thus, arterial stiffness was higher in the SA group. Plasma AOPP concentrations were higher in the SA group than in the EA group (SA: 31.7 ± 8.5, EA: 23.9 ± 6.9, Control: 27.2 ± 3.9 μmol/l). We found that plasma AOPP levels tended to be related to SAC ( P = 0.073, r = −0.31). Conclusions The present study provides a possibility that exercise training-induced oxidative stress may be partly involved in the mechanism underlying the adaptation of arterial stiffness in strength- and endurance-trained athletes.