Erythrocyte Glutathione Concentrations Research Articles

Oxidative and nitrosative stress — the leading mechanisms of chronic pancreatitis and chronic obstructive pulmonary disease interaction and inducers of their progression

Background. The frequency of chronic pancreatitis (CP) comorbidity with chronic obstructive pulmonary disease (COPD) has significantly increased recently. It may be accompanied by changes in oxidant-antioxidant homeostasis and activates a cascade of reactions of mutual burdening of these pathologies. The purpose of the current research was to evaluate the intensity of lipid peroxidation, oxidative modification of proteins and the state of individual factors of the antioxidant defense system in the development and course of CP, depending on the comorbid COPD. Materials and methods. Three hundred and seventeen patients were examined, including 62 patients with CP alone (group 1), 132 CP patients with comorbid COPD (group 2), 123 patients with COPD alone (group 3). The content in blood of isolated double bonds in compounds, conjugated dienes, ketodienes and conjugated trienes, malonic aldehyde, nitrites/nitrates, reduced glutathione, the activity of catalase, glutathione-S-transferase, glutathione peroxidase were evaluated in all patients. Results. In CP patients with comorbid COPD, the maximum oxidative stress intensity among the compared groups was registered. There was a reliable increase in the content of malonic aldehyde — by 2.0 times (p < 0.05), isolated double bonds — by 2.2 times (p < 0.05), conjugated dienes — by 1.9 times (p < 0.05), ketodienes and conjugated trienes — by 1.9 times (p < 0.05), nitrites/nitrates — by 2.6 times (p < 0.05). A reliable decrease in reduced glutathione content of erythrocytes was detec­ted: in group 1 — by 1.5 times, in group 2 — by 1.9 times (p < 0.05), in group 3 — by 1.2 times (p < 0.05). The compensatory increase in the activity of glutathione-S-transferase, glutathione peroxidase and blood catalase was revealed: in group 1 — by 1.3, 1.2 and 1.5 times (p < 0.05); in group 2 — by 1.5, 1.3 and 1.8 times (p < 0.05), in group 3 — by 1.2, 1.2 and 1.4 times, respectively (p < 0.05). Conclusions. The comorbid course of CP and COPD is accompanied by the maximum intensity of oxidative and nitrosative stress compared to the isolated course of the disease. An increase was detected in intermediate and final metabolites of peroxide oxidation in the blood, oxidative modification of proteins, nitrites/nitrates in the blood against the background of a deep imbalance of antioxidant defense factors, an increase in ceruloplasmin content in the blood, which requires the administration of antioxidant agents to correct detected disorders and prevent the progression of both comorbid diseases.

The modulatory action of taraxacum officinale on the glutathione system

The evaluation of the antioxidant activity of plants has been an important issue taking into account its importance on human health. Natural antioxidants protec t cells against oxidative stress, which can damage the cellular components. Taraxacum officinale (TO) leaves (TOL) and roots (TOR) has been commonly used in traditional medicine due to biologically active ingredients. This plant is rich in substances with high antioxidant activity (flavonoids, phenolic acids, coumarins, vitamins etc.). Glutathione represents the most abundant thiol of cells with important functions in the antioxidant system. Until now, there are no comprehensive data about TO extracts action on glutathione content.The objective of the study was to report the influence of TOL and TOR ethanolic extracts on the glutathione content of erythrocytes. TOL and TOR were harvested from a natural habitat of Republic of Moldova. The dry plants were extracted using ethanol as solvent (10, 20, 25, 40, 50 and 80% (v/v)). As source of glutathione were red blood cells (RBC) of healthy persons. As a result we determined that TO exhibits a modulatory action on glutathione content. The highest (28.03±1.14 µM/g. Hb) content of GSH was determined due to action of roots extracts made on ethanol of 20%, the lowest (10.88±0.83 µM/g. Hb) in case of leaves extracted on alcohol of 20%. Opposite, the lowest (5.92±0.72 µM/g. Hb) amount of GSSG was determined as a result of action of radicular extracts made on ethanol of 20%. The highest (11.46±3.27 µM/g. Hb) concentration of GSSG was determined by influence of roots extracts on ethanol of 50%.In conclusion, Taraxacum officinale exhibits a strong antioxidant activity. This plant has ability to prevent and treat the damage of cells caused by oxidative stress process, by actioning on glutathione system. This activity depends of ethanol concentrations and plant’s part.

The Impact of Dehydration and Hyperthermia on Circulatory Glutathione Metabolism after Exercise in the Heat with Insights into the Role of Erythrocytes.

Background: Reduced glutathione (GSH) is one of the main thiols involved in antioxidant defense. Changes in circulatory levels of GSH during exercise are associated with hyperthermia and dehydration. The mechanisms by which these alterations occur are not entirely known. We hypothesize that erythrocytes could be an important source of circulatory GSH during heat stress conditions. We performed two separate experiments to address this hypothesis. Methods: In the first experiment, we sought to investigate the impact of exercise in the heat and dehydration on erythrocyte levels of GSH. A total of 10 men performed 60 min of cycling at 60% VO2peak in the heat (38.0 ± 0.9 °C) or in a control temperate environment (23.0 ± 1.0 °C), both with and without dehydration. Relative humidity ranged from 50 to 70%. Blood samples were taken before and after exercise to measure GSH and oxidized (GSSG) glutathione. In the second experiment, erythrocytes were isolated from blood samples taken at rest and heated in vitro to determine the impact of heat on erythrocyte glutathione content. Tubes with erythrocytes were exposed to water baths at different temperatures; one tube was exposed to a water bath at 35 °C and the other tube to a water bath at 41 °C for a period of 30 min. After exposure to heat, plasma and erythrocytes were extracted for GSH and GSSG analyses. Results: Dehydration decreased circulatory GSH, regardless of ambient temperature (temperate and heat decreased 15.35% and 30.31%, respectively), resulting in an altered redox balance. Heat increased GSH levels in vitro. Conclusion: Our data suggest that dehydration decreases circulatory GSH levels regardless of environmental temperature. In addition, in vitro data suggests that erythrocytes may contribute to the release of GSH during exposure to heat stress.

Safety and efficacy of a ribose-cysteine supplement to increase erythrocyte glutathione concentration in healthy dogs.

To evaluate the safety of oral administration of a d-ribose-l-cysteine (RibCys) supplement to dogs and the effect of this supplementation on erythrocyte glutathione (GSH) concentration. 24 healthy adult dogs. In a randomized, double-blinded, controlled trial, dogs received 500 mg of a RibCys supplement or placebo (n = 12/group), PO, every 12 hours for 4 weeks. Dogs were evaluated weekly by means of a physical examination, CBC, serum biochemical analysis, urinalysis, and owner-completed quality-of-life questionnaire. Erythrocyte GSH concentration was measured on day 0 (ie, the day before treatment began) and weekly during supplementation. No dose-limiting adverse effects were noted in any dog. Two dogs in each group had mild, self-limiting diarrhea and anemia. No significant increase in erythrocyte GSH concentration was noted in either group at any time point. Two dogs in the RibCys group had improved skin and coat health and improved clinical signs of osteoarthritis. No clinical or owner-perceived improvements were noted in the placebo group. The RibCys supplement was safe and well tolerated in all dogs. Owners reported improvements in dermatologic and orthopedic conditions in some dogs in the RibCys group. No significant differences were observed in erythrocyte GSH concentration before or after RibCys treatment. This lack of significant differences may have been attributable to the use of healthy dogs, which would not be expected to have depleted GSH concentrations. Given the observed safety profile of RibCys, additional research is warranted to explore the potential usefulness of RibCys supplementation in dogs with cancer and those undergoing treatment for cancer.

Blood Plasma Quality Control by Plasma Glutathione Status.

Timely centrifugation of blood for plasma preparation is a key step to ensure high plasma quality for analytics. Delays during preparation can significantly influence readouts of key clinical parameters. However, in a routine clinical environment, a strictly controlled timeline is often not feasible. The next best approach is to control for sample preparation delays by a marker that provides a readout of the time-dependent degradation of the sample. In this study, we explored the usefulness of glutathione status as potential marker of plasma preparation delay. As the concentration of glutathione in erythrocytes is at least two orders of magnitude higher than in plasma, even the slightest leakage of glutathione from the cells can be readily observed. Over the 3 h observation period employed in this study, we observed a linear increase of plasma concentrations of both reduced (GSH) and oxidized glutathione (GSSG). Artificial oxidation of GSH is prevented by rapid alkylation with N-ethylmaleimide directly in the blood sampling vessel as recently published. The observed relative leakage of GSH was significantly higher than that of GSSG. A direct comparison with plasma lactate dehydrogenase activity, a widely employed hemolysis marker, clearly demonstrated the superiority of our approach for quality control. Moreover, we show that the addition of the thiol alkylating reagent NEM directly to the blood tubes does not influence downstream analysis of other clinical parameters. In conclusion, we report that GSH gives an excellent readout of the duration of plasma preparation and the associated pre-analytical errors.

Influence of the breeding environment factors on the number of the weaned piglets

Article Details: Received: 2020-10-22 | Accepted: 2020-11-27 | Available online: 2021-01-31 https://doi.org/10.15414/afz.2021.24.mi-prap.131-134 A prerequisite for the successful pig breeding isthe achievement of high reproductive performance, which can be influenced by several environmental factors. Therefore, the aim of our research was to assess the impact of the season, microclimatic indicators and technology of housing of the lactating sows on the number of the weaned piglets in the litter. The experiment was performed on a production farm in Slovakia and a total of 800 litters were evaluated. The results have shown that the season had a statistically significant effect on the number of the weaned piglets ( p <0.01), least in the summer and most of them in the fall. The highest number of the weaned piglets was found at the temperatures from 18 to 22 °C ( p <0.05), temperatures outside the stated range had a negative impact on the number of the weaned piglets. An increase of the relative humidity - above 70% ( p <0.05) and an increase in the flow - above 0,4 m.s -1 ( p <0.05) led to a decrease in the number of the weaned piglets. In the housing with a freemovement of the lactating sows, the number of the weaned piglets was higher than with the restricted movement ( p <0.05). Keywords: microclimate, technology, weaned piglets References Boudný, J. & Spicka, J. (2012). The effect of production efficiency on economic results in pig breeding. Res. Pig Breeding , 6(1), 1-8. Close, W. (1992). Thermoregulation in piglets: Environmental and metabolic consequences. BSAP Occasional Publication ,15, 25-33. https://doi.org/10.1017/S02639674067 English, P. R. & Edwards, S. A. (1996). Management of the nursing sow and her litter. In Dunkin A. C. & Taverner, M. (eds.). Pig Production. World Animal Science (Vol. C10 ). Amsterdam, Netherlands: Elsevier (pp. 113-140). Holmes, C. W. & Mount, L. E. (1967). Heat loss from groups of growing pigs under various conditions of environmental temperature and air movement. J. Anim. Prod. , 9, 435-452. https://doi.org/10.1017/S0003356100042008 Horký, P. (2014). Influence of increased dietary selenium on glutathione peroxidase activity and glutathione concentration in erythrocytes of lactating sows. Ann. Anim. Scie. , 14(4), 869-882. https://doi.org/10.2478/aoas-2014-0056 Matousek, V. et al. (2013). Livestock breeding II. Ceske Budějovice : JU ZF. In Czech. Myer, R. & Bucklin, R. (2018). Influence of hot-humid environment on growth performance and reproduction of swine. AN107: UF/IFAS Extension , 1-6. Nevrkla, P. et al. (2016). analysis of reproductive parameters in sows with regard to their health status. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis . 64, 481-486. https://doi.org/10.11118/actaun201664020481. Novak, P. & Rožňovský, J. (2009). Influence of microclimate on the pig performance. In Current knowledge about the pig breeding: proceedings from the International Scientific Conference 41 held on the occasion of the 90th anniversary of MZLU in Brno . Brno: MZLU (pp. 45-48). In Czech. Prunier, A. et al. (1996). Environmental and seasonal influences on the return-to-oestrus after weaning in primiparous sows. Livestock Production Science , 45, 103-110. https://doi.org/10.1016/0301-6226(96)00007-3 Rodrigues, S. V., Pla, L. M. & Albornoz, V. M. (2012). Modeling tactical planning decisions through a linear optimization model in sow farms. Livest. Sci. , 143(2-3), 162-171. Rolinec, M. (2020). The Effect of coconut oil addition to feed of pigs on rectal microbial diversity and bacterial abundance. Animals (Basel) , 10(10), E1764. https://doi.org/10.3390/ani10101764 Rozkot, M. (2014). Pigs technology and the public. Nas chov , 74(10), 63-66. In Czech. Sallvik, K. & Walberg, K. (1984). The effects of air velocity and temperature on the behaviour and growth of pigs. J. of Agricultural Engineering. Research , 30, 305-312. https://doi.org/10.1016/S0021-8634(84)80031-1 Silva, B. A. N. et al. (2006). Effect of floor cooling on performance of lactating sows during summer. Livest. Sci. , 105, 176-184. https://doi.org/10.1016/j.livsci.2006.06.007 Suriyasomboon, A. et al. (2006). Effect of temperature and humidity on reproductive performance of crossbred sows in Thailand. Theriogenology , 65, 606-628. https://doi.org/10.1016/j.theriogenology.2005.06.005 Vanerhaeghe, C. et al. (2010). Longitudinal field study to assess sow level risk factors associated with stillborn piglets. Anim. Reprod. Sci., 120(1-4), 78-83. https://doi.org/10.1016/j.anireprosci.2010.02.010 Wegner, K. et al. (2014). Climatic effects on sow fertility and piglet survival under influence of a moderate climate. Animal , 8(9), 1526-1533. https://doi.org/10.1017/S1751731114001219.

Systemic redox biomarkers suggest non-redox mediated processes in the prevention of bed rest-induced muscle atrophy after exercise training: The Cologne RSL study

It has been previously reported that eccentric-biased exercise training prevents the decreases in lean body mass after 60 days of head tilt down bed rest (“Cologne RSL Study”). The aim of the present study, as a part of Cologne RSL Study, was to investigate whether these anti-atrophy effects of exercise training are regulated by redox processes, as assessed indirectly via redox biomarkers in blood and urine. Twenty-four volunteers (N = 24) participated in a randomized controlled study and were randomly divided into two groups: a jump training group (JUMP, n = 12) that performed a specific eccentric-biased training protocol on a Sledge Jump System and a control group (CON, n = 11; one drop-out) that did not perform any exercise. All participants maintained a 6° head tilt down position for 24 h/day for 60 days. Redox measurements in plasma, erythrocytes and urine were performed at several time points throughout the study (i.e., baseline, intervention and recovery phases). A main effect of time was found for all dependent variables (P < .05). In particular, plasma protein carbonyls, erythrocyte catalase activity and urine F2-isoprostanes increased, while erythrocyte glutathione concentration decreased over time in both groups. In contrast, neither a main effect of group nor a significant group × time interaction was found in any of the measured variables (P > .05). In conclusion, our findings in systemic redox biomarkers indicate that the anti-atrophy effects of exercise training during a 60-day bed rest protocol are not regulated by redox processes.

Buprenorphine and Methadone as Opioid Maintenance Treatments for Heroin-Addicted Patients Induce Oxidative Stress in Blood.

Buprenorphine and methadone are two substances widely used in the substitution treatment of patients who are addicted to opioids. Although it is known that they partly act efficiently towards this direction, there is no evidence regarding their effects on the redox status of patients, a mechanism that could potentially improve their action. Therefore, the aim of the present investigation was to examine the impact of buprenorphine and methadone, which are administered as substitutes to heroin-dependent patients on specific redox biomarkers in the blood. From the results obtained, both the buprenorphine (n = 21) and the methadone (n = 21) groups exhibited oxidative stress and compromised antioxidant defence. This was evident by the decreased glutathione (GSH) concentration and catalase activity in erythrocytes and the increased concentrations of thiobarbituric acid reactive substances (TBARS) and protein carbonyls in the plasma, while there was no significant alteration of plasma total antioxidant capacity (TAC) compared to the healthy individuals (n = 29). Furthermore, methadone revealed more severe oxidant action compared to buprenorphine. Based on relevant studies, the tested substitutes mitigate the detrimental effects of heroin on patient redox status; still it appears that they need to be boosted. Therefore, concomitant antioxidant administration could potentially enhance their beneficial action, and most probably, buprenorphine that did not induce oxidative stress in such a severe mode as methadone, on the regulation of blood redox status.

Ameliorative role of a combination of chitosan, calcium, vitamins A and E against high fat diets-induced adverse effects in rats

BackgroundChitosan is a promising natural source for controlling obesity. Obese people tend to use supplementary nutrients to compensate for their deficiencies in their diets. The present study aimed to investigate the combined effect of chitosan, calcium, and vitamins A and E supplements against the adverse effects of high-fat diet consumption in rats.MethodsTwenty-five male albino rats were assigned into five equal groups. Control rats were fed standard basal diet (SBD). Another group was fed high-fat diet (HFD) without supplements. The other three groups were fed HFD containing 0, 400, and 800 mg of chitosan per kilogram diet, in presence of calcium and vitamins A and E supplements, daily for 10 weeks.ResultsAs compared to controls, rats fed HFD without supplements showed significant elevations in body weight gain, feed consumption, relative weights of the heart and liver, serum levels of total cholesterol, triglycerides, low-density lipoprotein cholesterols, very low-lipoprotein triglycerides, urea, creatinine, and malondialdehyde, as well as serum activities of alanine and aspartate aminotransferases, alkaline phosphatase, and creatine kinase. Moreover, significant declines in the relative kidney weight, serum levels of high-density lipoprotein cholesterols, total proteins, albumin, globulin, calcium, vitamins A and E, erythrocyte glutathione content, and superoxide dismutase activity were recorded. Histopathological alterations were observed in rats fed HFD with or without supplements. On contrary, rats fed HFD containing chitosan and supplements showed remarkable improvement in all the studied parameters towards control values, in dose-dependent manner.ConclusionChitosan, calcium, and vitamins A and E attenuated the adverse effects caused by HFD intake in rats.

The Effects of Swimming Training in Cold Water on Antioxidant Enzyme Activity and Lipid Peroxidation in Erythrocytes of Male and Female Aged Rats.

The aim of this study was to verify whether eight-week-long swimming exercise training would evaluate the level of selected indicators of the pro-oxidant/antioxidant status in response to cold water in comparison with swimming under thermoneutral conditions in sedentary male and female elderly rats. The exercise-trained groups swam four min/day and five days a week during eight weeks of housing. Exercise was performed by swimming in glass tanks containing tap water maintained according to group at 5 °C and 36 °C. At the end of treatment (48 h after the last session), all rats were anaesthetized. The level of chosen biomarkers of oxidative stress and antioxidant enzyme activity was determined in the red blood cells and plasma. The results of study show that female rats seem to be better adapted to changing thermal conditions of the environment, developing not only morphological, but also antioxidant, defense mechanisms, mainly in the form of increased erythrocyte superoxide dismutase (SOD) activity and glutathione (GSH) concentration to restore the pro-oxidant/oxidant balance of the organism. Significantly higher concentrations of GSH were observed in the female rats of the group swimming in cold water (by 15.4% compared to the control group and by 20.5% in relation to the group of female rats swimming at 36 °C). In the group exposed to swimming training exercise in cold water, a significantly higher activity of SOD1 (by 13.4%) was found compared to the control group. On the other hand, the organs of ageing male rats show a reduced capacity to increase the metabolic response to low temperatures compared to female ones. In addition, it was demonstrated that cold exposure leads to an increase in lipid peroxidation in tissues. On the other hand, the repeated exposure to low levels of oxidative stress may result in some adaptive changes in organisms that help them to resist stress-induced damage.

Variation in the Markers of Nutritional and Oxidative State in a Long-Lived Seabird: Associations with Age and Longevity

Age-related declines in life-history traits have been widely observed in free-living animals. Several theories link senescence to oxidative stress. The aim of this study was to measure several widely used markers of oxidative and nutritional state in a long-lived seabird, the common gull (Larus canus), in order to assess the suitability of these markers for describing deterioration in physiological condition associated with chronological age and survival. Associations with longevity and individual consistency of these parameters over the years (repeatability) were also assessed. Senescence in fitness parameters was observed during the study period: in females, laying date and clutch mass were related to bird age in a curvilinear manner, with middle-aged birds breeding earlier and laying heavier eggs. The only parameter associated with aging processes was glutathione concentration in erythrocytes, which was lower in female birds with longer life spans. Of indexes of nutritional state, plasma triglyceride concentration showed a between-individual increase with age, suggesting selective mortality of birds with low levels. Additionally, total plasma protein levels of individual males increased with age. The mostly negative results of this study hint that the commonly used parameters of physiological condition and oxidative state used in this study do not adequately reflect an individual's long-term health condition. Alternatively, it is possible that in common gulls, senescence occurs in reproductive mechanisms but not in mechanisms responsible for maintaining an organism's redox balance, consistent with the idea that different aspects of an organism's physiological condition age at different rates. Significant interannual repeatability was detected in three plasma constituents-carotenoids, uric acid, and total protein-all of which can possibly be linked to variation in dietary habits.

GLUTATHIONE SYSTEM INDICES AND CHOLESTASIS ENZYMES IN ACUTE ALCOHOLIC INTOXICATION

Aim. The aim of the study was to assess in experiment the changes in glutathione system and activity of cholestasis system in acute alcoholic intoxication against the background of preliminary alcoholization. Materials and methods. The study was performed on 64 white rats. Acute ethanol intoxication was modeled on intact animals against the background of preliminary alcoholization. Acute poisoning was caused by intragastric introduction of 40 % ethanol solution in the dose of 0,5 LD50. Gamma-glutamiltranspeptidase and leucinaminopeptidase activity was determined spectrophotometrically in blood plasma, reduced glutathione content and glutathionreductase activity were assessed in blood erythrocytes. Results. In case of acute ethanol poisoning, blood plasma leucinaminopeptidase and gamma-glutamiltranspeptidase activity was raised, erythrocyte gluthatione content was increased. In case of acute ethanol intoxication against the background of preliminary alcoholization, erythrocyte glutathione content is decreased, gamma-glutamiltranspeptidase activity remained elevated, but leucinaminopeptidase and glutathionreductase activity did not significantly differ from the control. Conclusions. Determination of reduced glutathione content in peripheral blood erythrocytes and cholestasis enzymes activity in blood plasma is significant for the assessment of severity of cytotoxic hepatic lesion and development of cholestasis in acute alcoholic intoxication.

Assessment of the role of thymol in combating chromium (VI)-induced oxidative stress in isolated rat erythrocytes in vitro

Thymol, the main phenolic compound in Thymus vulgaris, has been shown to have various biological effects. The main objective of this study was to investigate the efficacy of thymol on counteracting hexavalent chromium-induced oxidative damage in rat erythrocytes in vitro. The radical scavenging activity of thymol was examined using the 1, 1-diphenyl-2-picrylhydrazyl assay. Erythrocytes resistance to oxidative damage, lipid peroxidation, osmotic pressure, hemolysis as well as morphological alterations were evaluated in the presence of 2.5 µg thymol mL−1 with or without 5 µmol hexavalent chromium mL−1 of the incubation media. Results from the 1,1-diphenyl-2-picrylhydrazyl assay denoted good radical scavenging activity of thymol. Thymol caused a significant increase in superoxide dismutase and catalase activities and reduced glutathione content in erythrocytes intoxicated with hexavalent chromium. In contrast, the presence of thymol resulted in markedly less-elevated malondialdehyde levels, hemolysis, and destabilization of erythrocytes exposed to hexavalent chromium. Microscopically, thymol markedly reduced hexavalent chromium-induced morphological alterations in rat red blood cells. Conclusively, thymol counteracted hexavalent chromium-induced oxidative damage in rat erythrocytes.

Identification and Quantification of Flavonoids from Two Southern Italian Cultivars of Allium cepa L., Tropea (Red Onion) and Montoro (Copper Onion), and Their Capacity to Protect Human Erythrocytes from Oxidative Stress.

Onions (Allium cepa) are consumed worldwide and represent an important source of dietary phytochemicals with proven antioxidant properties, such as phenolic acids, flavonoids, thiosulfinates, and anthocyanins. Epidemiological and experimental data suggest that regular consumption of onions is associated with a reduced risk of degenerative disorders. Therefore, it is of interest to investigate the biological properties of different varieties of onions. Here, we characterized for the first time a variety of onion, called Ramata di Montoro (coppery onion from Montoro), grown in a niche area in southern Italy, and compared its phenolic profile and antioxidant properties to a commercial ecotype of red onion, Tropea, also present in southern Italy. An analytical method based on high-performance liquid chromatography coupled with UV detection and mass spectrometry was used to separate and characterize the phenolic fraction (anthocyanins and flavonols) extracted from both coppery and red types. The main compounds detected in the two ecotypes were quercetin and quercetin glucosides, isorhamnetin glucosides, kaempferol glucoside, and, among anthocyanins, cyanidin glucosides. Tropea ecotype onion showed a higher content of flavonols (632.82 mg/kg fresh weight) than Montoro type onion (252.91 mg/kg fresh weight). Accordingly, the antioxidant activity of the former was 2.8-fold higher compared to the latter. More pronounced were the differences existing between the four anthocyanins detected in the two ecotypes, with those in the Tropea ecotype onion present at concentrations 20-230-fold higher than in the Montoro type onion. Both extracts reduced LDL oxidation about 6-fold and protected human erythrocytes from oxidative damage induced by HClO by about 40%. In addition, as a consequence of HClO treatment, glutathione concentration in erythrocytes was reduced about 50% and pretreatment with onion extracts induced a recovery of glutathione level by about 15-22%. Qualitative differences highlighted in the chemical composition of the two phenolic extracts, especially the total content of anthocyanins, which was 30-fold higher in Montoro type onion compared to Tropea ecotype, can be associated with the protective effects measured against oxidative damage induced in human erythrocytes.

Amino acid supplementation in l-dopa treated Parkinson's disease patients

The correlation between Parkinson disease and malnutrition is well established, however a protein-restricted diet is usually prescribed because of potentially negative interactions between dietary amino acids and l-dopa pharmacokinetics. This strategy could increase the risk of further nutritional deficits. A monocentric, prospective, randomized, double-blind pilot study was performed on two groups of Parkinson-affected, protein-restricted, patients: Intervention (n = 7; amino acid supplementation twice daily) and Placebo (n = 7; placebo supplementation twice daily). At enrolment, after 3- and 6-month supplementation, neurological evaluations (UPDRS III, Hoenh-Yahr scale, l-dopa equivalent dose assessment) were performed and blood sample was collected to define insulin sensitivity (QUICKI index) and oxidative stress (oxidized and reduced glutathione). Repeated measure ANCOVA was applied to define time effect and time × treatment interaction. Participants were comparable at baseline for all assessed parameters. Neurological outcomes and l-dopa requirement were comparable in both group after 6-month of supplementation, without time × treatment interaction. The decrease in insulin sensitivity, as assessed by QUICKI index, observed after 6 months in both groups, was greater in Placebo than in Intervention (time effect p < 0.001; time × treatment interaction p = 0.01). Moreover, despite no changes in total erythrocyte glutathione concentrations, oxidized glutathione levels decreased by 28 ± 17% in the Intervention while increased by 55 ± 38% in Placebo (time effect p = 0.05; time × treatment interaction p = 0.05), after 6-month supplementation. Amino acid supplementation, assumed with shrewd temporal distribution, did not show detrimental effects on neurological and pharmacological control in protein-restricted Parkinson-affected patients, chronically treated with l-dopa. Furthermore, daily amino acid supplementation partially counteracted insulin resistance development and the loss in antioxidant availability.

Influence of Increased Dietary Selenium on Glutathione Peroxidase Activity and Glutathione Concentration in Erythrocytes of Lactating Sows

Abstract We studied the influence of different selenium (Se) levels on some parameters of the antioxidant potential of lactating sows. The experiment involved 15 sows of the Large White breed divided into 3 equal groups. The addition of Se (from Se-enriched yeast) amounted to 0.0, 0.25 and 0.50 mg per kg of diet in the control, Se1 and Se2 groups, respectively. Erythrocyte Se concentration, glutathione peroxidase (GPx) activity and reduced/oxygenated glutathione ratio were measured as some of the indicators of the sow’s antioxidant status. Supplementation of Se at 0.25 mg/kg of diet increased Se concentration (by 50.0%; P&lt;0.01), GPx activity (by 17.0%: P&lt;0.05) and reduced/ oxygenated glutathione ratio (by 29.7%; P&lt;0.05). Addition of Se at 0.50 mg/kg of diet increased Se concentration (by 63.6%; P&lt;0.01), GPx activity (by 34.7%; P&lt;0.01) and reduced/oxygenated glutathione ratio (by 64.0%; P&lt;0.01). A significant relationship (P&lt;0.01) was found between the Se concentrations and activity of GPx in erythrocytes from sows in the Se1 and Se2 groups (r=0.76 and 0.77, respectively). Percentage of piglets weaned/born was higher (P&gt;0.05) in the Se2 than in the Se1 and control groups. In summary, addition of 0.25 or 0.50 mg Se/kg of diet can improve antioxidant status of lactating sows, but addition of 0.25 mg Se/kg may be also sufficient.

Effect of transport on blood selenium and glutathione status in feeder lambs.

Stress from transport may be linked to increased generation of reactive oxygen species, the removal of which requires reduced glutathione and selenium. The aim of this experiment was to examine the effect of transport on glutathione and Se status of feeder lambs. Recently weaned lambs (n = 40) were blocked by gender and BW on d 0 of the experiment and randomly assigned to 2 treatment groups: group 1, no transport and full access to feed and water (control), and group 2, 8-h road transport followed by another 16 h of feed deprivation (transport). After 24 h, both treatment groups were treated the same. All lambs were weighed, and blood samples were collected at 0, 8, 24, and 72 h and analyzed for whole-blood (WB) and serum Se concentrations, serum NEFA concentrations, and erythrocyte concentrations of glutathione. Transport of feeder lambs for 8 h followed by another 16 h of feed deprivation transiently (significant at 24 h but no longer different at 72 h) decreased BW and erythrocyte glutathione concentrations and increased serum NEFA and blood Se concentrations compared with control lambs. Our results suggest that 8 h of transport followed by another 16 h of feed deprivation results in fatty acid and Se mobilization from tissue stores with a coincident decrease in erythrocyte glutathione concentrations.

Effects of randomized supplementation of methionine or alanine on cysteine and glutathione production during the early phase of treatment of children with edematous malnutrition

We have shown that a low glutathione concentration and synthesis rate in erythrocytes are associated with a shortage of protein-derived cysteine in children with edematous severe acute malnutrition (SAM). We tested the hypothesis that methionine supplementation may increase protein-derived cysteine and upregulate cysteine synthesis, thereby improving glutathione synthesis during the early treatment of edematous SAM. The cysteine flux, its de novo synthesis and release from protein breakdown, and erythrocyte glutathione synthesis rate were measured in 12 children with edematous SAM in the fed state by using stable isotope tracers at 3 clinical phases as follows: 3 ± 1 d (±SE) [clinical phase 1 (CP1)], 8 ± 1 d [clinical phase 2 (CP2)], and 14 ± 2 d (clinical phase 3) after admission. Subjects were randomly assigned to receive equimolar supplements (0.5 mmol ⋅ kg(-1) ⋅ d(-1)) of methionine or alanine (control) immediately after CP1. In the methionine compared with the alanine group, cysteine flux derived from protein breakdown was faster at CP2 than CP1 (P < 0.05), and the change in plasma cysteine concentration from CP1 to CP2 was greater (P < 0.05). However, there was no evidence of a difference in cysteine de novo synthesis and its total flux or erythrocyte glutathione synthesis rate and concentration between groups. Methionine supplementation increased cysteine flux from body protein but had no significant effect on glutathione synthesis rates. Although cysteine is made from methionine, increased dietary cysteine may be necessary to partially fulfill its demand in edematous SAM because glutathione synthesis rates and concentrations were less than previous values shown at full recovery. This study was registered at clinicaltrials.gov as NCT00473031.

The effect of lead-induced oxidative stress on blood viscosity and rheological properties of erythrocytes in lead exposed humans

Lead-induced oxidative stress has been identified as the essential factor in lead poisoning pathogenesis. Therefore, the present study examined the association between occupational lead exposure and blood rheological parameters with respect to malondialdehyde (a lipid peroxidation product), lipofuscin, and glutathione concentrations in erythrocytes. The examined group included 283 healthy male employees of lead-zinc works. In brief, 129 workers were classified as the low-exposure group, while the high-exposure group was composed of 154 workers. The mean blood levels of lead and zinc-protoporphyrin and the mean urine concentrations of delta-aminolevulinic acid were used as exposure markers. The control group consisted of 73 healthy male administrative workers. Whole blood viscosity was elevated in both exposure subgroups compared with the control group. Erythrocyte aggregability increased significantly; although the increase was greater in the low exposure group. Erythrocyte deformability decreased in both subgroups. The levels of malondialdehyde and lipofuscin were significantly elevated, whereas the glutathione content decreased. In conclusion, occupational exposure to lead may induce oxidative stress in erythrocytes. This stress elevates whole blood viscosity and disturbs erythrocyte aggregability and deformability. There is a dose-effect relationship between lead levels and blood rheological parameters.

Oxidative stress and antioxidant enzyme activity in South Indian male smokers with chronic obstructive pulmonary disease

Oxidative stress resulting from tobacco smoking has been suggested to play a role in the pathogenesis of chronic obstructive pulmonary disease (COPD). The aim of the present study was to evaluate the oxidant and antioxidant levels in smokers with and without COPD. Two hundred thirty-six patients with COPD and 150 smokers with no respiratory problems were selected. COPD diagnosis and staging was done based on the Global Initiative for Chronic Obstructive Lung Disease criteria. Plasma malondialdehyde (MDA) and erythrocyte glutathione (GSH) concentrations and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-s-transferase (GST) activities were assessed. COPD patients had higher levels of MDA and lower levels of antioxidants when compared with controls (P < 0.01). Analysis of variance revealed increase in MDA (P < 0.05) and decrease in CAT activity (P < 0.01) and GSH (P < 0.05) level with the progression of the disease. In patients, lung function positively correlated with CAT and SOD activities and negatively correlated with MDA levels (P < 0.01). Smoking history showed negative relation with forced expiratory volume in 1 s (FEV1 )/forced vital capacity (P < 0.05) and positive correlation with CAT activity (P < 0.01). MDA levels negatively correlated with SOD (r = -0.239; P < 0.01). In controls, MDA levels showed significant positive correlation with FEV1 and GPx (P < 0.05) and negative correlation with GSH (P < 0.01). Logistic regression showed association of higher MDA levels with increased risk and higher levels of CAT and GSH with decreased risk of progressing in the disease (odds ratio = 2.938, 2.538, 7.860). Our study demonstrates that there is an oxidant antioxidant imbalance in COPD patients and suggests the importance of GPx in maintaining lung function.