Factorial analysis of N-acetylcysteine and propolis treatment effects on symptoms, life quality and exacerbations in patients with Chronic Obstructive Pulmonary Disease (COPD): a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: Standard treatment for chronic obstructive pulmonary disease (COPD) includes inhalation therapy along with mucoactive drugs. The aim of this study was to assess the efficacy and safety of orally administered mucolytic N-acetylcysteine and propolis (NACp) in COPD patients. PATIENTS AND METHODS: A randomized, double-blind, prospective, interventional, 6 months study was conducted at the Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia. Effects of daily NACp administration (600 mg, 1200 mg or placebo) on exacerbation, life quality (St. George's Respiratory Questionnaire-SGRQ), symptoms (COPD assessment test-CAT; Visual analogue cough scale-VAS; Leicester Cough Questionnaire-LCQ; Medical Research Council Dyspnoea scale-mMRC) and spirometric parameters in 120 COPD patients were assessed. Tests were conducted at three-time points: baseline, after three months and after 6 months of NACp treatment. RESULTS: Repeated measures ANOVA showed that pulmonary function parameters, 6-minute walk test and mMRC score did not significantly change during the study. Cough VAS and CAT scores were significantly different between groups as within experimental groups. LCQ and SGRQ scores did not differ between placebo, and both examined groups, but within each examined group statistically significant difference was confirmed in observed parameters during therapy. Factorial analysis and subsequent binary logistic regression revealed "Symptoms related factor" as the strongest predictor of exacerbation for supplemented groups (p<0.01). CONCLUSIONS: Treatment with high NACp for 6 months is safe and beneficial for cough and expectoration symptoms and improves the life quality. NACp significantly reduces acute exacerbation frequency in COPD patients by controlling COPD related symptoms.

Novel leukocyte and thrombocyte indexes in patients with prediabetes and type 2 diabetes mellitus.

OBJECTIVE: To our knowledge, there are no studies that investigated the relationship between diabetes mellitus type 2 (T2D) and some novel indexes, such as monocyte/granulocyte to lymphocyte ratio (M/GLR), derived neutrophil to lymphocyte ratio (dNLR), and platelets to neutrophil ratio (PNR). The aim of this study was to examine the association between these novel indexes and glycated hemoglobin (HbA1c) in patients with prediabetes and T2D. PATIENTS AND METHODS: A total of 827 participants were consecutively recruited. According to the American Diabetes Association (ADA) criteria, participants were divided into control, prediabetes, and T2D group. RESULTS: White blood cell count (WBC), neutrophil count, NLR, dNLR, and M/GLR were higher in T2D patients than in the other two groups, whereas PNR was the lowest in T2D group. Lymphocyte count was higher in prediabetes and T2D patients than in control group. Multivariable ordinal regression analysis showed that WBC, neutrophil count, lymphocyte count, NLR, dNLR, and M/GLR were positively associated [OR (95% CI) 1.287 (1.191-1.390), p<0.001; 1.427 (1.275-1.594), p<0.001; 1.347 (1.130- 1.606), p=0.001; 1.350 (1.090-1.670), p=0.006; 1.662 (1.189-2.326), p=0.003; 1.275 (1.057-1.540), p=0.012, respectively] with HbA1c. However, PNR was negatively associated with HbA1c [0.987 (0.981-0.993), p<0.001]. CONCLUSIONS: Novel, modified NLR indexes, such as dNLR and M/GLR were independently correlated with HbA1c. Also, PNR showed superiority over platelets (PLT) in relation to HbA1c. These novel indexes might give a significant contribution to the timely recognition of disturbances of glucose homeostasis in patients with prediabetes and overt diabetes.

A combination of N-acetyl cysteine and propolis attenuates oxidative-inflammatory parameters during COPD exacerbation.

OBJECTIVE: The aim of this study was to determine any differences in oxidative stress and inflammation parameters in COPD patients treated with either N-acetyl cysteine (NAC) alone or with NAC in combination with propolis (NACP). PATIENTS AND METHODS: Forty COPD patients in the exacerbation phase were enrolled into the study and were treated with either NAC (NAC group; n=20) or NACP (NACP group; n=20) twice daily for one month. Redox status was determined by measuring superoxide anion (O2.-), advanced oxidation protein products (AOPP), total oxidative status (TOS), prooxidative-antioxidant balance (PAB), malondialdehyde (MDA), ischemia modified albumin (IMA) and several other antioxidant markers: superoxide dismutase (SOD), paraoxonase 1 (PON1), total sulfhydryl groups (SHG) and total antioxidant status (TAS). Interleukins 6, 8 and 17 were measured as markers of inflammatory status. RESULTS: Both groups had similar socio-demographic and clinical characteristics. After treatment significantly higher SHG [0.446 (0.395-0.516) vs. 0.292 (0.270-0.325), p<0.001] and significantly lower TOS - 50.6 [49.7-53.4 vs. 73.2 (50.9-84.6), p<0.05] - and IMA [0.650 (0.629-0.682) vs. 0.709 (0.667-0.756), p<0.05] - were found in the NACP group compared to the NAC group. Factorial analysis indicated a larger oxidative stress-inflammatory load in the NAC group after treatment. CONCLUSIONS: From an oxidative stress and inflammatory status perspective, treatment with NACP was more successful than with NAC. The inclusion of propolis into therapy for COPD patients, especially those in the exacerbation phase, could prove beneficial.

Oxidative stress and inflammation parameters-novel biomarkers for idiopathic pulmonary fibrosis.

OBJECTIVE: The pathophysiological mechanisms of idiopathic pulmonary fibrosis (IPF) are not well elucidated. It is assumed that oxidative stress and inflammation are the key underlying culprits for its onset and progression. To gain deeper insight into these processes, we have evaluated several oxidative stress parameters, inflammation markers [i.e., high sensitivity C-reactive protein (hsCRP), serum amyloid A1 (SAA1)], soluble programmed cell death-ligand 1 (sPD-L1), and 25-hydroxyvitamin D [25(OH)D] in IPF patients. PATIENTS AND METHODS: Biochemistry analyses were done in 30 consecutive IPF patients and 30 age and gender-matched healthy control group (CG). RESULTS: IPF patients had significantly higher advanced oxidation protein products (p<0.001), pro-oxidant-antioxidant balance (p=0.010), total oxidative status (p<0.001), and ischemia modified albumin (p<0.001) compared to CG. Lower total antioxidant status and total sulfhydryl groups (tSGH) and significantly higher sPD-L1, hsCRP (p<0.001 for all), SAA1 proteins (p=0.014) and [25(OH)D] severe deficiency [11.0 (9.6-15.1) nmol/L] in IPF patients compared to CG were observed. Paraoxonase 1 activity and hsCRP level were lower, while tSHG and sPD-L1 were higher in IPF patients with more severe disease (i.e., II+III stage compared to I stage, p<0.05 for all). CONCLUSIONS: IPF patients are in a state of profound oxidative stress compared to healthy people. The inflammatory component of the disease was confirmed by higher hsCRP and SAA1, but lower [25(OH)D] in IPF than in healthy people. Also, higher levels of sPD-L1 in patients with IPF compared to healthy individuals suggest that sPD-L1 may have a significant role in immune response in IPF.

Polyphenol rich extracts of Geranium L. species as potential natural antioxidant and antimicrobial agents.

OBJECTIVE: Plants and plant extracts are of great scientific interest due to the chemical diversity and pharmacological properties of present bioactive molecules. The Geranium L. species are widely used in ethnomedicine. In the current study, the total phenolic and tannin content, antioxidant and antimicrobial activity of methanol extracts of eight Geranium species were investigated. MATERIALS AND METHODS: The total phenolic and tannin content were determined by the FC method. Antioxidant capacity was evaluated in FRAP, DPPH, and biochemical assays, while antimicrobial activity was examined using the broth microdilution method. RESULTS: The high total phenolic (170.64-636.32 mg GAE/g dry extract) and tannin content (37.80-414.02 mg GAE/g DE), along with significant total antioxidant (FRAP values 1.13-8.80 mmol Fe2+/g) and DPPH radical scavenging activity (SC50 values 4.24-34.52 µg/mL) were observed. The prominent antioxidant capacity was confirmed in biochemical assays (OS values -1.47 - -13.02). The extracts exhibited significant antimicrobial activity against ATTC strains (MICs dominantly in the range of 12.5-200 µg/mL) as well as against clinical isolates of E. coli (MICs mostly 50 and 100 µg/mL). The pronounced antioxidant and antimicrobial activity can be due to the high phenolic content, particularly due to the presence of hydrolyzable tannins. CONCLUSIONS: Based on the high content of polyphenols, pronounced antioxidant and antimicrobial activities, the examined extracts are promising natural antioxidant and antimicrobial agents with the potential medicinal purpose and use as a functional food.

Effects of monacolin K-containing nutraceutical on cholesterol homeostasis re-establishment and CVD risk reduction in hypercholesterolemic subjects.

OBJECTIVE: Hypercholesterolemia is caused by cholesterol homeostasis (CH) disruption, and it contributes to cardiovascular diseases pathogenesis and progression. Status of CH can be assessed by measuring serum concentrations of non-cholesterol sterols (NCS) which serve as cholesterol synthesis and absorption surrogate markers. Monacolin K, isolated from red yeast rice, influences cholesterol synthesis by inhibiting HMG-CoA reductase activity and reduces serum total cholesterol (TC) concentration. PATIENTS AND METHODS: This longitudinal study included 30 hypercholesterolemic patients, with systematic coronary risk estimation (SCORE) values <10%, who received 3-months-long supplementation with nutraceutical mixture containing monacolin K, and vitamins C, B1 and K2. Serum NCS were quantified by HPLC-MS/MS method. Atherogenic indexes were calculated from lipid status parameters concentrations. Albumin degradation inhibition test was conducted to estimate in vitro anti-inflammatory activity of the nutraceutical mixture, whereas in vitro antioxidant activity was measured in serum enriched with prooxidants and antioxidants. RESULTS: TC, LDL-cholesterol (LDL-C), and triglycerides (TG) concentrations (p<0.001), as well as atherogenic indexes and SCORE values (p<0.001, p<0.01, respectively) were lowered following the supplementation. Concentrations of cholesterol synthesis markers were decreased (p<0.001), whereas levels of cholesterol absorption markers remained unchanged after the supplementation. Reduction in cholesterol synthesis went alongside reductions in lipid status parameters and atherogenic indexes. In vitro analyses showed certain anti-inflammatory and antioxidant activity of the nutraceutical. CONCLUSIONS: These results suggest that supplementation with monacolin K containing nutraceutical favorably influences lipid status parameters and atherogenic indexes by acting on cholesterol synthesis. Anti-inflammatory and antioxidant effects of this unique nutraceutical mixture may exhibit beneficial pleiotropic effects.

Paraoxonase 1 low activity and SYNTAX score may predict postoperative complications after coronary artery surgery.

OBJECTIVE: Coronary artery bypass grafting (CABG) seems to present a powerful trigger of oxidative stress (OS) and acute inflammatory response. This study aimed to estimate the effects of off-pump coronary artery bypass (OPCAB) grafting on the OS that is commonly observed in patients undergoing operation under cardiopulmonary bypass (CPB). Additionally, we aimed to examine the relationship between and paraoxonase 1 (PON1) activity and the degree of stenosis, severity and complexity of the atherosclerotic lesions, estimated by SYNTAX score (SS). PATIENTS AND METHODS: Study group of 107 patients scheduled for CABG were divided into CPB and OPCAB group. Blood samples for OS markers measurement were collected at six-time intervals: before skin incision (t1), immediately after surgery (t2), 6h (t3), 24h (t4), 48h (t5) and 96h after cessation of the operation and surgical trauma (t6). SS was calculated. RESULTS: A significant decrease in lipid hydroperoxides (LOOH) and advanced oxidation protein products (AOPP) levels after both types of surgeries were observed, whereas PON1 reduction was observed higher in the CPB than in the OPCAB group. A significant inverse correlation between SS values and PON1 activity, preoperatively and during the early postoperative hours after surgery [in t2, t3 time intervals (p<0.05 for all)] was found. ROC analysis showed that for CPB patients, Model with all OS parameters showed excellent accuracy (AUC=0.957, p<0.001) for prediction postoperative complications. CONCLUSIONS: Decrease in PON1 activity during the early post-operative phases was related to higher SS. This relationship was more convincing in CPB, compared with OPCAB patients. Moreover, integrated models of OS status parameters have the capability to predict the development of postoperative complications.

Total oxidant status and oxidative stress index as indicators of increased Reynolds risk score in postmenopausal women.

OBJECTIVE: Considering the knowledge gap between underlying pathophysiological mechanisms of oxidative stress and increased cardiovascular risk, the present study aimed to examine the potential relationship between total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) and the Reynolds Risk Score (RRS) in the cohort of postmenopausal women. PATIENTS AND METHODS: A total of 126 postmenopausal women participated in this cross-sectional study. Blood pressure, anthropometric and biochemical markers were determined. OSI was calculated as the TOS/TAS ratio. Associations of biochemical parameters with RRS were tested using univariable and multivariable logistic ordinal regression analysis. RESULTS: TOS and OSI were the highest in women in high RRS category compared to moderate and low risk ones (p<0.001, for both). There was no difference in TAS level across RRS categories (p=0.370). Multivariable ordinal regression analysis showed independent association of TOS and OSI with RRS when tested with other clinical variables [OR=2.45; 95% CI (1.08-5.53); p=0.031 and OR=2.84; 95% CI (1.27-6.36); p=0.011, respectively]. CONCLUSIONS: TOS and OSI are associated with the RRS in the cohort of postmenopausal women. Longitudinal studies are needed to confirm whether adding the TOS and OSI to the standard RRS algorithm could improve its potential to predict cardiovascular event.

Inverse association between serum endocan levels and small LDL and HDL particles in patients with type 2 diabetes mellitus.

OBJECTIVE: Determination of lipoprotein size and subclasses distribution can provide more significant information on cardiovascular disease risk than measurement of traditional lipid parameters alone. Accordingly, we aimed to examine their potential relationship with the novel biomarker of endothelial dysfunction, such as endocan in patients with type 2 diabetes mellitus (T2D), since there are no studies concerning this issue. PATIENTS AND METHODS: This case-control study included a total of 42 individuals with T2D and 64 diabetes-free participants. Serum endocan, lipid parameters, and lipoprotein subclasses were measured. RESULTS: Patients with T2D exhibited higher proportion of the smallest high-density lipoprotein (HDL) particles HDL 3c, as compared with diabetes-free participants (p=0.047). Higher serum endocan levels in T2D patients with low small dense low-density lipoprotein (LDL) particles (sdLDL) %, as compared with corresponding group of diabetes-free subjects was shown (p<0.01). Univariate binary logistic analysis revealed significant positive association of endocan and LDL diameter (OR=1.686, p=0.004), and negative associations of endocan with proportions of sdLDL (OR=0.928, p=0.007) and HDL3b (OR=0.789, p=0.009) particles. In a multivariate analysis, LDL diameter and proportions of sdLDL and HDL3b subclasses remained independent predictors of endocan levels in tested population. CONCLUSIONS: The results of our study showed that larger LDL diameters, but lower sdLDL and HDL3b proportions were associated with higher endocan levels in population with T2D. More studies in the future are needed to confirm the observed relationship and to examine its causal nature.

Endocan and advanced oxidation protein products in adult population with hypertension.

OBJECTIVE: Hypertension is closely related to oxidative stress and inflammation. Endocan is a new inflammation marker whose role is not completely elucidated in hypertension. The aim of this study was to explore the association between endocan and several oxidative stress markers [i.e., advanced oxidation protein products (AOPP), total protein sulfhydryl (SH-) groups and prooxidant-antioxidant balance (PAB)] in adult population with hypertension. PATIENTS AND METHODS: A total of 90 patients with hypertension were compared with 44 controls. Blood pressure, anthropometric and biochemical parameters were measured. Associations of clinical data with hypertension were tested with univariable and multivariable logistic ordinal regression analysis. RESULTS: Endocan and AOPP were significantly higher in hypertensive patients than in the controls (p=0.006 and p=0.046, respectively). In the multivariable logistic regression analysis, AOPP and endocan kept their independent positive associations with hypertension. As AOPP rose by 1 µmol/L and endocan rose by 1 pg/mL, the probability for hypertension presence rose by 4.2% and 32.2%, respectively and 39.9% of variation in hypertension could be explained with the Model. The area under the Receiver Operating Characteristic curve [(AUC) for AOPP=0.638 (0.550-0.719), p=0.01 and for endocan=0.679 (0.593-0.757), p<0.001] demonstrated sufficient clinical accuracy towards hypertension. On the contrary, the Model showed very good clinical accuracy [AUC= 0.825 (0.749-0.900), p<0.001]. CONCLUSIONS: Endocan and AOPP are independently correlated with hypertension in adult population and these tested markers together could be reliable parameters to discriminate patients with hypertension from normotensive ones.

Lipid peroxidation as risk factor for endothelial dysfunction in antiphospholipid syndrome patients.

The aim of this study was to evaluate oxidative stress markers and it relations to endothelial damage as risk factor for thrombosis in patients with primary (PAPS) and secondary (SAPS) antiphospholipid syndrome (APS) in correlation to traditional risk factors. Flow-mediated (FMD) and nitroglycerine (NMD)-induced dilation of the brachial artery were studied in 140 APS patients (90 PAPS, 50 SAPS) and 40 controls matched by age, sex, and conventional risk factors for atherosclerosis. Markers of oxidative stress, lipid hydroperoxydes (LOOH), advanced oxidation protein products (AOPP), total sulfhydryl groups (tSHG), and paraoxonase 1 activity (PON1) were determined by spectrophotometric method. Oxidative stress dominates in APS patients. LOOH and AOPP correlate to lipid fractions (p < 0.05), unlike PON1, tSHG that correlated to antiphospholipid antibody positivity (p < 0.05). FMD was lower in APS patients comparing to controls (p < 0.001). Cholesterol is independent variable for FMD impairment in control group (p = 0.011); LOOH in PAPS (p = 0.004); LOOH, aCL, and triglycerides in SAPS patients (p = 0.009, p = 0.049, and p = 0.012, respectively). Combined predictive of aCL and LOOH is better for FMD impairment than LOOH alone in both PAPS and SAPS patients (AUC 0.727, p = 0.001, 95 % CI 0.616-0.837 and AUC 0.824, p˂0.001, 95 % CI 0.690-0.957, respectively). Lipid peroxidation is independent predictor for endothelial dysfunction in APS patients. We demonstrated synergistic effect of aCL and LOOH as risk for endothelial impairment in both PAPS and SAPS patients.

Effects of short- and long-term physical activity on DNA stability and oxidative stress status in young soccer players.

AIM: The aim of the study was to determine whether single soccer training is able to cause oxidative stress and DNA instability. We have also sought to investigate if adaptive response will be developed during 45 days training period and to what extent. METHODS: This study was conducted on 16 soccer players aged 18.13±0.35 years. We used single cells gel electrophoresis (comet assay) to investigate leukocyte DNA stability. The results were presented as DNA score and percent of cells with medium and high damage. Oxidative status of our subjects was estimated through blood levels of superoxide anion, the thiobarbituric acid-reacting substances (TBARs), total antioxidant status (TAS), total oxidant status (TOS), prooxidant-antioxidant balance (PAB) and sulfhydryl-groups (SH-groups). RESULTS: During single soccer training, DNA score and percent of the cells with medium and high damage were increased after training but without significance. Sulphydryl-groups (P=0.033), TOS (P=0.002) and PAB (P=0.045) were significantly lower after training. After 45 days training period DNA score was decreased but with no significance. However, percent of cells with medium and high damage was significantly lower (P=0.01). TOS (P=0.001) and MDA (P=0.038) levels were also significantly lower, while sulphydryl-groups levels were significantly higher (P=0.006). CONCLUSION: This study demonstrated that single soccer training had not compromised DNA stability. Possible development of oxidative stress was effectively neutralized by very well preserved antioxidative mechanisms. It was also shown that during 45 days adaptive response was induced. All measured parameters should be considered as useful information on oxidative status of trainees.

Effect of astaxanthin supplementation on muscle damage and oxidative stress markers in elite young soccer players.

AIM: The purpose of the current study was to examine the effect of Astaxanthin (Asx) supplementation on muscle enzymes as indirect markers of muscle damage, oxidative stress markers and antioxidant response in elite young soccer players. METHODS: Thirty-two male elite soccer players were randomly assigned in a double-blind fashion to Asx and placebo (P) group. After the 90 days of supplementation, the athletes performed a 2 hour acute exercise bout. Blood samples were obtained before and after 90 days of supplementation and after the exercise at the end of observational period for analysis of thiobarbituric acid-reacting substances (TBARS), advanced oxidation protein products (AOPP), superoxide anion (O2•¯), total antioxidative status (TAS), sulphydril groups (SH), superoxide-dismutase (SOD), serum creatine kinase (CK) and aspartate aminotransferase (AST). RESULTS: TBARS and AOPP levels did not change throughout the study. Regular training significantly increased O2•¯ levels (main training effect, P<0.01). O2•¯ concentrations increased after the soccer exercise (main exercise effect, P<0.01), but these changes reached statistical significance only in the P group (exercise x supplementation effect, P<0.05). TAS levels decreased significantly post- exercise only in P group (P<0.01). Both Asx and P groups experienced increase in total SH groups content (by 21% and 9%, respectively) and supplementation effect was marginally significant (P=0.08). Basal SOD activity significantly decreased both in P and in Asx group by the end of the study (main training effect, P<0.01). All participants showed a significant decrease in basal CK and AST activities after 90 days (main training effect, P<0.01 and P<0.001, respectively). CK and AST activities in serum significantly increased as result of soccer exercise (main exercise effect, P<0.001 and P<0.01, respectively). Postexercise CK and AST levels were significantly lower in Asx group compared to P group (P<0.05) CONCLUSION: The results of the present study suggest that soccer training and soccer exercise are associated with excessive production of free radicals and oxidative stress, which might diminish antioxidant system efficiency. Supplementation with Asx could prevent exercise induced free radical production and depletion of non-enzymatic antioxidant defense in young soccer players.

Proxidant* antioxidant balance in supplemented elite female volleyball athletes during a six week training period.

AIM: The objectives of this study were: 1) to evaluate pro-oxidant-antioxidant balance (PAB) associations with the commonly measured parameters of oxidative stress and antioxidatve defence in elite female volleyball athletes; 2) to investigate changes in the parameters of oxidative stress during a period of intense training and dietary antioxidant supplementation. METHODS: Twenty-seven female volleyball players participated in this study. Blood samples were collected the day before the pre-competitive mesocycle training period began. After the first blood sample donation and during the next six weeks fourteen players (supplemented group) received a cocktail of antioxidants while thirteen of them (control group) received no dietary supplementation. The following parameters were measured: reactive oxygen metabolites (ROMs), superoxide anion (O2-), malondialdehyde (MDA), advanced oxidation protein products (AOPP), lipid hydroperoxides (LOOH), biological antioxidative potential (BAP), paraoxonase activity toward paraoxon (POase) and diazoxon (DZOase), superoxide dismutase (SOD), total sulphydryl group concentration (SH groups) and pro-oxidant-antioxidant balance. RESULTS: Significant associations were observed between biomarkers of oxidative damage with PAB in multiple linear regression model in the supplemented and the control groups (82.3% vs. 83.1%) before training and in the control group (82.1%) after training. Significant associations between antioxidative defence parameters and PAB values were found in the supplemented group after six-weeks of training (57%). CONCLUSION: In the absence of antioxidant supplementation, PAB values were dependent on the association with biomarkers of oxidative damage before and after training. After a six-week training period and the applied antioxidant supplementation, PAB values were under the influence of non-enzymatic anti-oxidative defence.

Oxidative stress and anti-oxidative defense in schoolchildren residing in a petrochemical industry environment.

OBJECTIVE: To evaluate the possible relationship between industrial air pollution and oxidative stress in schoolchildren by comparing parameters from children residing in two nearby localities with contrasting environmental conditions. PARTICIPANTS: 42 schoolchildren (12-15 years) from Pancevo (site of Serbias largest petrochemical installation) formed the exposed group. 82 schoolchildren from Kovacica village, located 30 km north of Pancevo, formed the non-exposed group. METHODS: Oxidative stress status, anti-oxidative defense parameters, paraoxonase-1 status, lipid status, glucose concentration and leukocyte counts were compared in two groups. RESULTS: The children from Pancevo showed higher level of oxidative stress demonstrated by an elevated malondialdehyde concentration (P <0.001) and decreased superoxide dismutase activity (P<0.01) in comparison to the non-exposed group. CONCLUSIONS: The results suggested a relationship between the presence of air pollutants and increased oxidative stress in schoolchildren residing in an industrial environment.

Long-term effects of oxidative stress in volleyball players.

The aim of this study was to determine the impact of long-term training on elite female volleyball players and to determine parameters that could discriminate them according to the level of oxidative stress-associated adaptation. Fifty-four elite female volleyball players were divided into 3 groups (1: below-average training experience <8.0 years, 2: average training experience between 8.0 and 10.5 years and 3: above-average training experience >10.5 years). The measured parameters were reactive oxygen metabolites, biological anti-oxidative potential, superoxide anion, malondialdehyde, advanced oxidation protein products, lipid hydroperoxides, paraoxonase activity, superoxide-dismutase activity and sulphydryl groups. Multiple discriminant analysis of the oxidative stress status parameters between the three groups of athletes indicated a statistically significant difference (Wilks' lambda=0.458, X(2)=35.898, p=0.031). The most important discriminant variables, superoxide-dismutase and superoxide anion, were the best indicators of differences between groups with different training experience. The significantly higher values were found in Group 3 compared with Group 1 in superoxide-dismutase activity (141+/-32 vs. 86+/-46; p=0.002), sulphydryl groups (p=0.031), and reactive oxygen metabolites (p=0.042). The significantly lower superoxide anion was found between Group 3 and Group 1 (377+/-187 vs. 1183+/-905; p=0.001). Oxidative stress status parameters adequately discriminated 68.5% of athletes with different training experience.

Association of oxidative stress and PON1 with LDL and HDL particle size in middle-aged subjects.

BACKGROUND: Alterations in plasma lipoprotein subclass distributions affect atherosclerosis risk. Smaller, denser low-density lipoprotein (LDL) particles (sdLDL) are more susceptible to oxidation. In contrast, most of the protective effects of high-density lipoproteins (HDL) are attributable to larger particles. This study investigates the connection between LDL and HDL particle heterogeneity and oxidative stress, antioxidative defence (AOD) and paraoxonase (PON1) status in a healthy middle-aged Serbian population. MATERIALS AND METHODS: LDL and HDL particle sizes and subclass distributions were measured by gradient gel electrophoresis in 104 men and 103 women, aged 53 +/- 9.4 years. PON1 activities and PON1(Q192R) phenotypes were determined with paraoxon and diazoxon as substrates. The oxidative stress/AOD status was estimated by measuring malondialdehyde (MDA) and superoxide-anion (O2*(-)) levels and superoxide-dismutase (SOD) activity. RESULTS: Subjects with sdLDL had significantly higher MDA (P < 0.001) and O2*(-)(P < 0.05) levels and greater diazoxonase (DZOase) activity (P < 0.05) compared to subjects with larger LDL particles. A high MDA concentration was a significant predictor of the sdLDL phenotype (P < 0.005). Increased levels of and MDA were associated with smaller HDL(3) subclass abundance. Reduced HDL particle size was associated with lower DZOase activity (P < 0.01). CONCLUSIONS: Even in the absence of symptoms of atherosclerosis, sdLDL particles are associated with increased oxidative stress, which may stimulate a compensatory rise in PON1 DZOase activity. Elevated oxidative stress may significantly affect HDL subclass distribution, resulting in the accumulation of smaller, denser HDL particles with diminished antioxidative capacity.