A new approach to spectroscopic and structural studies of the nano-sized silicate-substituted hydroxyapatite doped with Eu3+ ions.

Nanocrystalline silicate-substituted hydroxyapatites Ca10-xEux(PO4)4(SiO4)2(OH)2 (where x = 0.5, 1.0, 2.0, 5.0 mol%) doped with Eu3+ ions were synthesized using a microwave assisted hydrothermal method and heat-treated in the temperature range from 700 to 1000 °C. The concentration of optically active Eu3+ ions was established in the range of 0.5-5 mol% to investigate the preference of occupancy sites. The structural and morphological properties of the obtained biomaterials were determined by using XRD (X-Ray Powder Diffraction), TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy) techniques as well as infrared (IR) spectroscopy. The average particle sizes were calculated to be in the range from 20 nm to 80 nm by the Rietveld method. The charge compensation mechanism in europium(iii)-doped silicate-substituted hydroxyapatite was proposed in the Kröger-Vink-notation. The luminescence properties (the emission, excitation spectra and emission kinetics) of the Eu3+ ion-doped apatite were recorded depending on the dopant concentration. The existence of Eu2+ ions was confirmed by the emission spectra.

Cytokines and cellular inflammatory sequence in non-athletes after prolonged exercise.

AIM: The goal of the study was to clarify the sequence of cytokines and inflammatory cells in non-athletes performed an intense running exercise. METHODS: Sixteen young healthy men participated in the exercise trial that involved 90-min run at 65% VO2max. RESULTS: The plasma concentrations of anti-inflammatory cytokines IL-4, IL-6 and IL-10 increased immediately after exercise simultaneously with number of white blood cells. Between IL-6 and IL-10, and neutrophils the relationships were observed. The correlation value for IL-6 and neutrophils was 0.775 whereas for IL-10 and neutrophils was 0.506. The proinflammatory cytokines IL-1ß and TNFα were detected at 6 h after exercise and moderately correlated with monocytes count. The high level of proinflammatory cytokines, monocytes and creatine kinase (CK) remained until 48 h rest. The CK activity significantly correlated with IL-1ß (r=0.578) and TNFα (r=0.452), and also with monocytes count (r=0.439). CONCLUSION: The results have shown that: 1) exercise induces anti-inflammatory cytokines production first and then proinflammatory cytokines; and 2) prolonged proinflammatory response is closely related with muscle damage present.

Changes of muscle-derived cytokines in relation to thiol redox status and reactive oxygen and nitrogen species.

The aim of this study was to compare the levels of the plasma muscle-derived cytokines (myokines) and reactive oxygen and nitrogen species (RONS) after muscle damage triggered by different exercises, and to demonstrate the relationships between RONS, thiol redox status and myokines. Sixteen young men participated in a 90-min run at 65% VO2max (Ex.1) or 90-min run at 65% VO2max finished with a 15-min eccentric phase (Ex.2, downhill running). Plasma samples were collected before and at 20 min, 24 h and 48 h after exercise. The exercise trials significantly elevated the concentrations of plasma hydrogen peroxide (H2O2) and 8-isoprostane at 20 min rest. Myokines IL-6 and IL-10 increased at 20 min rest while IL-1ß and TNFα increased at 24 h rest following both running. Ex.2 caused a significant increase in nitric oxide (NO), IL-6, IL-10 and oxidized glutathione (GSSG) levels. Thiol redox status (GSH(total)-2GSSG/GSSG) decreased by about 30% after Ex.2 as compared to Ex.1. H2O2) and NO directly correlated with IL-6, IL-10, IL-1ß, TNFα and glutathione. These results show that eccentric work is an important factor that enhances the production of RONS and muscle-derived cytokines, and that there is a possible participation of thiol redox status in the release of myokines to blood.

Modulatory effect of N-acetylcysteine on pro-antioxidant status and haematological response in healthy men.

The aim of this study was to follow up whether the modification of pro-antioxidant status by 8-day oral application of N-acetylcysteine (NAC) in healthy men affects the haematological response, whether there is a direct relationship between antioxidant defences and erythropoietin (EPO) secretion and whether NAC intake enhances exercise performance. Fifteen healthy men were randomly assigned to one of two groups: control or NAC (1,200 mg d(-1) for 8 days prior to and 600 mg on the day of exercise trial). To measure the ergogenic effectiveness of NAC, subjects performed incremental cycle exercise until exhaustion. NAC administration significantly influenced the resting and post-exercise level of glutathione (+31%) as well as the resting activity of glutathione enzymes (glutathione reductase, -22%; glutathione peroxidase, -18%). The oxidative damage markers, i.e., protein carbonylation and lipid peroxidation products (thiobarbituric acid reactive substance) were reduced by NAC by more than 30%. NAC noticeably affected the plasma level of EPO (+26%), haemoglobin (+9%), haematocrit (+9%) and erythrocytes (-6%) at rest and after exercise. The mean corpuscular volume and the mean corpuscular haemoglobin increased by more than 12%. Plasma total thiols increased by 17% and directly correlated with EPO level (r = 0.528, P < 0.05). NAC treatment, contrary to expectations, did not significantly affect exercise performance. Our study has shown that 8-day NAC intake at a daily dose of 1,200 mg favours a pro-antioxidant status and affects haematological indices but does not enhance exercise performance.

Modulatory effect of N-acetylcysteine on pro-antioxidant status and haematological response in healthy men

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The aim of this study was to follow up whether the modification of pro-antioxidant status by 8-day oral application of N-acetylcysteine (NAC) in healthy men affects the haematological response, whether there is a direct relationship between antioxidant defences and erythropoietin (EPO)secretion and whether NAC intake enhances exercise performance. Fifteen healthy men were randomly assigned to one of two groups: control or NAC (1,200 mg d−1 for 8 days prior to and 600 mg on the day of exercise trial). To measure the ergogenic effectiveness of NAC, subjects performed incremental cycle exercise until exhaustion. NAC administration significantly influenced the resting and post-exercise level of glutathione (+31%) as well as the resting activity of glutathione enzymes (glutathione reductase, −22%; glutathione peroxidase, −18%). The oxidative damagemarkers, i.e., protein carbonylation and lipid peroxidation products (thiobarbituric acid reactive substance) were reduced by NAC by more than 30%. NAC noticeably affected the plasma level ofEPO (+26%), haemoglobin (+9%), haematocrit (+9%) and erythrocytes (−6%) at rest and after exercise. The mean corpuscular volume and the mean corpuscular haemoglobin increased by more than 12%. Plasma total thiols increased by 17% and directly correlated with EPO level (r = 0.528, P < 0.05). NAC treatment, contrary to expectations, did not significantly affect exercise performance. Our study has shown that 8-day NAC intake at a daily dose of 1,200 mg favours a pro-antioxidant status and affects haematological indices but does not enhance exercise performance (AU)

The comparison of antioxidant and hematological properties of N-acetylcysteine and alpha-lipoic acid in physically active males.

The aim of this study was to follow up whether the modification of pro-antioxidant status by oral thiol administration such as N-acetylcysteine and alpha-lipoic acid affects the hematological response. Twenty-eight healthy men participated in two independent experiments. Subjects were randomly assigned to one of four groups: controls (C(NAC) and C(ALA)), N-acetylcysteine (NAC) and alpha-lipoic acid (ALA). 1200 mg of N-acetylcysteine, 600 mg of alpha-lipoic acid or placebo were administered for 8 days in two doses. NAC or ALA administration significantly elevated plasma total antioxidant status (TAS) and reduced protein carbonylation (PC) and lipid peroxidation (TBARS) by more than 30 %. The reduced glutathione (GSH) and hematological parameters changed only in response to NAC administration. NAC significantly elevated the level of GSH (+33%), EPO (+26%), Hb (+9%) and Hct (+9%) compared with C(NAC). The mean corpuscular volume (MCV) and the mean corpuscular hemoglobin (MCH) also increased by more than 12% after NAC. The numerous negative or positive correlations between the measures of TAS, PC, TBARS and hematological parameters were found, which suggest the NAC-induced interaction between pro-antioxidant and hematological values. Our study has shown that both N-acetylcysteine and alpha-lipoic acid intake reveal an antioxidant action, but only N-acetylcysteine improves the haematological response.

Pro-antioxidant ratio in healthy men exposed to muscle-damaging resistance exercise.

The purpose of this study was to compare the pro-antioxidant status in healthy men exposed to muscle-damaging resistance exercise, and to investigate the practical application of Loverro's coefficient (P/A ratio) to evaluate the presence of oxidative stress. Twenty-eight healthy men were assigned to two groups performed multi-joint (M) or single-joint (S) resistance exercise. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) as well as the concentration of lipid peroxidation products (TBARS) in blood were evaluated. The P/A ratio was calculated from the mean values of erythrocyte TBARS, SOD, CAT and GPx. Creatine kinase (CK) activity was used as a marker of muscle damage. The applied resistance exercises triggered off the changes in pro-antioxidant ratio towards peroxidation which was proved by significant increase in erythrocyte TBARS concentration in M (+25%) and S (+27%) groups. Plasma TBARS increased only after multi-joint resistance exercise and correlated with erythrocyte P/A ratio (r = 0.536, P < 0.01). The multi-joint exercise caused decrease in SOD activity by 28% whereas the single-joint resistance exercise elevated enzyme activity by 20%. Activities of the other antioxidant enzymes changed simultaneously i.e. CAT activity increased by 14%-16% immediately after exercise, and GPx activity declined by 18%-34% during recovery in M and S groups. Even though, all erythrocyte parameters significantly changed following multi-joint and single-joint resistance exercises, the assessment of pro-antioxidant ratio showed the considerable increase in P/A only in M group. In summary, an analysis of pro- and antioxidant parameters showed significant changes in response to muscle-damaging exercise and demonstrated the practical application of P/A ratio to evaluate the risk of oxidative stress in athletes.

Pro-antioxidant ratio in healthy men exposed to muscle-damaging resistance exercise

The purpose of this study was to compare the pro-antioxidant status in healthymen exposed to muscle-damaging resistance exercise, and to investigate the practicalapplication of Loverro’s coefficient (P/A ratio) to evaluate the presence of oxidativestress. Twenty-eight healthy men were assigned to two groups performed multi-joint(M) or single-joint (S) resistance exercise. The activities of superoxide dismutase(SOD), glutathione peroxidase (GPx) and catalase (CAT) as well as the concentrationof lipid peroxidation products (TBARS) in blood were evaluated. The P/A ratio wascalculated from the mean values of erythrocyte TBARS, SOD, CAT and GPx. Creatinekinase (CK) activity was used as a marker of muscle damage. The applied resistanceexercises triggered off the changes in pro-antioxidant ratio towards peroxidationwhich was proved by significant increase in erythrocyte TBARS concentrationin M (+25%) and S (+27%) groups. Plasma TBARS increased only after multi-jointresistance exercise and correlated with erythrocyte P/A ratio (r= 0.536, P< 0.01). Themulti-joint exercise caused decrease in SOD activity by 28% whereas the single-jointresistance exercise elevated enzyme activity by 20%. Activities of the other antioxidantenzymes changed simultaneously i.e. CAT activity increased by 14%-16%immediately after exercise, and GPx activity declined by 18%-34% during recoveryin M and S groups. Even though, all erythrocyte parameters significantly changedfollowing multi-joint and single-joint resistance exercises, the assessment of proantioxidantratio showed the considerable increase in P/A only in M group. In summary,an analysis of pro- and antioxidant parameters showed significant changes inresponse to muscle-damaging exercise and demonstrated the practical application ofP/A ratio to evaluate the risk of oxidative stress in athletes (AU)

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Prooxidant-antioxidant equilibrium in rowers: effect of a single dose of vitamin E.

AIM: The purpose of this research was to explain whether a single dose of vitamin E influences on disturbances of pro-oxidant-antioxidant equilibrium induced a laboratory 2,000 m rowing test. METHODS: The athletes were divided into two groups: vitamin E (1.000 mg alfa-tocopherol acetate) and P (placebo: cod-liver oil) supplemented 3 h before exercise. In the subjects' blood levels of following parameters were estimated: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), lipid peroxidation products (TBARS) and protein carbonyls (PC). Creatine kinase (CK) and beta-glucuronidase (betaG) activities were also measured as markers of muscle damage. RESULTS: The applied exercise at maximal intensity (lactate: vitamin E=14.39+/-1.77 mmol/L, P=14.09+/-1.4 mmol/L) caused significant changes in the tested parameters in both groups: SOD (vitamin E Ø30%, P Ø50%), CAT (vitamin 70%, P 12%), GPx (vitamin 49%, P 45%), TBARS (vitamin 70%, P 71%), PC (vitamin 41%, P 78%), CK (vitamin 19%, P 32%), betaG (vitamin 42%, P 47%). The P/A ratio (TBARS/SOD+CAT+GPx) was significantly lower in vitamin E in comparison with placebo, but after 30 min and 24 h restitution it returned to pre-exercise level. Between P/A ratio and PC concentration there was observed positive correlation (P<0.001). No effect of vitamin E on CK and betaG activities were observed. CONCLUSIONS: A single dose of 1,000 mg vitamin E enhances oxidative defense thus attenuates oxidative damage but it is not so much relevant to recommend the antioxidant supplementation by rowers.

Oxidative stress in burnt children.

BACKGROUND: One of the effects of burn injury is production of reactive oxygen species increasing general-structural damage. Such a condition is called oxidative stress. The purpose of this research was to find out whether oxidative stress is present in burnt children treated routinely and, if so, in which phase of the disease it is the most severe and how long it persists. MATERIAL AND METHODS: The study was carried out on a group of 84 burnt children. The patients were divided into 2 groups: lightly burnt (LB-N:55) and moderately to severely burnt (SB-N:29). Blood samples were collected based on hospitalization period within the 1st, 2nd, 3rd, 7th and 21st day, respectively, following the injury. Total antioxidative capacity (TAC) in plasma and concentration of lipid peroxidation products (TBARS) in red blood cells were estimated. The test results were compared to control group of 40 healthy children. RESULTS: The research showed a statistically significant decrease in TAC in both groups of burnt children. The TBARS concentration was increased in both groups within the 1st day following burn injury and maintained the high level throughout the research continuation. No statistically significant differences between LB and SB groups were recognized. CONCLUSIONS: The observed changes in the tested parameters are attributable to oxidative stress occurring in burn disease. For this reason, burn--injured children are recommended to receive exogenous antioxidants.

The influence of atherogenic diet and "essential" phospholipids upon the contents of noradrenaline and dopamine in the brain of rats and their exploratory activity.

The influence of atherogenic diet and "essential" phospholipids (EPL) both on exploratory activity and catecholamine content in the brain of rats has been examined. The atherogenic diet caused a decrease of the animals' exploratory activity as well as a diminution of catecholamines. It was observed that these changes correlated. Prophylactic administration of EPL is capable of preventing such changes. Therapeutic administration of EPL increased exploratory activity and catecholamines in the atherogenic group which subsequently received the basic laboratory diet.