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Protein Carbonyl Content (protein + carbonyl_content)
Selected AbstractsHigh total antioxidant activity and uric acid in tracheobronchial aspirate fluid of preterm infants during oxidative stress: an adaptive response to hyperoxia?ACTA PAEDIATRICA, Issue 3 2000G Vento The effect of O2 exposure, expressed by mean daily fractional inspired oxygen concentration (FiO2), was evaluated during the first 6 d of life in the tracheobronchial aspirate fluid of 16 mechanically ventilated preterm infants in terms of both antioxidant response and oxidative damage, by measuring total antioxidant activity, uric acid concentrations and protein carbonyl content. Each day linear regression analysis was performed and a positive correlation was found between total antioxidant activity and FiO2 during the study period, especially on day 2 of life (r= 0.91, p < 0.0001), but uric acid correlated only in the first 3 d, especially on the 2nd day (r= 0.83, p < 0.0001). No correlation was found between carbonyl content and FiO2. The highest values of total antioxidant activity (416 and 790 ,mol l,1) were found in 2 babies ventilated with highest FiO2: 1 and 0.80, respectively. Total antioxidant activity was not detectable or was very low in the babies not requiring O2 therapy. The highest value of uric acid (270 ,mol l,1) was found in the baby ventilated with 100% oxygen. Uric acid concentrations obtained in these babies were much higher then those reported in the bronchoalveolar lavage fluid of adults. Preterm babies seem to have an antioxidant response in the tracheobronchial aspirate fluid following an oxidative stress and uric acid may be physiologically important as an antioxidant of the respiratory tract, especially during the first days of life. [source] Free radical generation and oxidative stress with ageing and exercise: Differential effects in the myocardium and liverACTA PHYSIOLOGICA, Issue 4 2000Bejma Reactive oxygen species and other oxidants are implicated in the mechanisms of biological ageing and exercise-induced tissue damage. The present study examined the effects of ageing and an acute bout of exercise on intracellular oxidant generation, lipid peroxidation, protein oxidation and glutathione (GSH) status in the heart and liver of young adult (8 month, N=24) and old (24 month, N=24) male Fischer 344 rats. Young rats ran on treadmill at 25 m min,1, 5% grade until exhaustion (55.4 ± 2.7 min), whereas old rats ran at 15 m min,1, 5% until exhaustion (58.0 ± 2.7 min). Rate of dichlorofluorescin (DCFH) oxidation, an indication of intracellular oxidant production, was significantly higher in the homogenates of aged heart and liver compared with their young counterparts. In the isolated heart and liver mitochondria, ageing increased oxidant production by 29 and 32% (P < 0.05), respectively. Acute exercise increased oxidant production in the aged heart but not in the liver. When nicodinamide dinucleotide phosphate (reduced), adenosine diphosphate and Fe3+ were included in the assay, DCFH oxidation rate was 47 and 34% higher (P < 0.05) in the aged heart and liver homogenates, respectively, than the young ones. The age differences in the induced state reached 83 and 140% (P < 0.01) in isolated heart and liver mitochondria, respectively. Lipid peroxidation was increased in the aged liver and exercised aged heart, whereas protein carbonyl content was elevated only in the aged heart (P < 0.05). Although our data using DCFH method probably underestimated cellular oxidant production because of time delay and antioxidant competition, it is clear that oxidative stress was enhanced in both heart and liver with old age. Furthermore, aged myocardium showed greater susceptibility to oxidative stress after heavy exercise. [source] Evidence supporting an increased presence of reactive oxygen species in the diseased equine jointEQUINE VETERINARY JOURNAL, Issue 5 2000A. N. Dimock Summary Reactive oxygen species (ROS) are capable of degrading many components of the joint in the presence of insufficient antioxidant defences, and as a result have been implicated in the pathogenesis of joint disease in horses. However, to our knowledge, evidence of ROS occurring in diseased joints of horses has not been reported. The objective of this experiment was to compare differences in synovial fluid protein carbonyl content (as a marker of oxidative modification of synovial fluid proteins by ROS) and the antioxidant status of synovial fluid between clinically normal and diseased equine joints. Synovial fluid was collected from the metacarpophalangeal, metatarsophalangeal, carpal and tarsal joints of 4 horses, age 2,5 years, as controls, and from diseased joints (metacarpophalangeal, metatarsophalangeal, carpal, tarsal and/or femoropatellar) of 61 horses, age 2,5 years. Synovial fluid protein carbonyl content was higher (P<0.01) in diseased joints as compared to controls. Antioxidant status of synovial fluid from diseased joints was higher, but not significantly, than that of controls (P = 0.0595). These findings require further study to determine their contribution to the overall disease process. [source] Ferulic acid, a natural protector against carbon tetrachloride-induced toxicityFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 4 2005M. Srinivasan Abstract The present work is aimed at evaluating the protective effect of ferulic acid (FA), a naturally occurring phenolic compound on CCl4 induced toxicity. The activities of liver markers (alanine transaminase, aspartate transaminase, alkaline phosphatase, , -glutamyl transferase), lipid peroxidative index (thiobarbituric acid-reactive substances, hydroperoxides, nitric oxide, protein carbonyl content), the antioxidant status (superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione) were used as biomarkers to monitor the protective role of FA. The liver marker enzymes in plasma and lipid peroxidative index in liver and kidney were increased in CCl4 -treated groups, which were decreased significantly on treatment with FA. The antioxidants, which were depleted in CCl4 -treated groups, were improved significantly by FA treatment. Administration of FA to normal rats did not produce any harmful effects. Thus our results show that FA is an effective antioxidant without any side-effects and may be a great gain in the current search for natural therapy. [source] Protective effect of arjunolic acid against arsenic-induced oxidative stress in mouse brain,JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 1 2008Mahua Sinha Abstract Arsenic, a notoriously poisonous metalloid, is ubiquitous in the environment, and it affects nearly all organ systems of animals including humans. The present study was designed to investigate the preventive role of a triterpenoid saponin, arjunolic acid against arsenic-induced oxidative damage in murine brain. Sodium arsenite was selected as a source of arsenic for this study. The free-radical-scavenging activity and the in vivo antioxidant power of arjunolic acid were determined from its 2,2-diphenyl-1-picryl hydrazyl radical scavenging ability and ferric reducing/antioxidant power assay, respectively. Oral administration of sodium arsenite at a dose of 10 mg/kg body weight for 2 days significantly decreased the activities of antioxidant enzymes, superoxide dismutase, catalase, glutathione- S -transferase, glutathione reductase and glutathione peroxidase, the level of cellular metabolites, reduced glutathione, total thiols and increased the level of oxidized glutathione. In addition, it enhanced the levels of lipid peroxidation end products and protein carbonyl content. Treatment with arjunolic acid at a dose of 20 mg/kg body weight for 4 days prior to arsenic administration almost normalized above indices. Histological findings due to arsenic intoxication and arjunolic acid treatment supported the other biochemical changes in murine brains. Results of 2,2-diphenyl-1-picryl hydrazyl radical scavenging and ferric reducing/antioxidant power assays clearly showed the in vitro radical scavenging as well as the in vivo antioxidant power of arjunolic acid, respectively. The effect of a well-established antioxidant, vitamin C, has been included in the study as a positive control. Combining all, results suggest that arjunolic acid possessed the ability to ameliorate arsenic-induced oxidative insult in murine brain and is probably due to its antioxidant activity. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:15,26, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20209 [source] Aging induces cardiac diastolic dysfunction, oxidative stress, accumulation of advanced glycation endproducts and protein modificationAGING CELL, Issue 2 2005Shi-Yan Li Summary Evidence suggests that aging, per se, is a major risk factor for cardiac dysfunction. Oxidative modification of cardiac proteins by non-enzymatic glycation, i.e. advanced glycation endproducts (AGEs), has been implicated as a causal factor in the aging process. This study was designed to examine the role of aging on cardiomyocyte contractile function, cardiac protein oxidation and oxidative modification. Mechanical properties were evaluated in ventricular myocytes from young (2-month) and aged (24,26-month) mice using a MyoCam® system. The mechanical indices evaluated were peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR90) and maximal velocity of shortening/relengthening (± dL/dt). Oxidative stress and protein damage were evaluated by glutathione and glutathione disulfide (GSH/GSSG) ratio and protein carbonyl content, respectively. Activation of NAD(P)H oxidase was determined by immunoblotting. Aged myocytes displayed a larger cell cross-sectional area, prolonged TR90, and normal PS, ± dL/dt and TPS compared with young myocytes. Aged myocytes were less tolerant of high stimulus frequency (from 0.1 to 5 Hz) compared with young myocytes. Oxidative stress and protein oxidative damage were both elevated in the aging group associated with significantly enhanced p47phox but not gp91phox expression. In addition, level of cardiac AGEs was ,2.5-fold higher in aged hearts than young ones determined by AGEs-ELISA. A group of proteins with a molecular range between 50 and 75 kDa with pI of 4,7 was distinctively modified in aged heart using one- or two-dimension SDS gel electrophoresis analysis. These data demonstrate cardiac diastolic dysfunction and reduced stress tolerance in aged cardiac myocytes, which may be associated with enhanced cardiac oxidative damage, level of AGEs and protein modification by AGEs. [source] Oxidative stress and metabolism in animal model of colitis induced by dextran sulfate sodiumJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 11 2007Carlos R Damiani Abstract Background and Aim:, Ulcerative colitis is a chronic inflammatory disease of the gastrointestinal tract. Its etiology remains unclear, but it appears to result from a dysregulated immune response, with infiltration of phagocytic leukocytes into the mucosal interstitium. The production and release of reactive oxygen species by immune cells seems to play a crucial role in physiopathology of colitis. The aim of this work was to evaluate the effects of N-acetylcysteine (NAC) and deferoxamine (DFX) in the treatment of colitis induced by dextran sulfate sodium (DSS). Methods:, The effects of NAC and DRX on rats with DSS-induced colitis were determined by measuring intestinal parameters of oxidative stress and mitochondrial function, inflammatory response and bowel histopathological alterations. Results:, DSS increased white blood cells count and NAC and DFX did not prevent this effect. However, DSS increased mitochondrial respiratory chain complex IV in colon of rats and NAC and DFX prevented this alteration. In addition, thiobarbituric acid reactive substances were increased in colon of DSS-treated rats. NAC and DFX, when taken together, prevented this effect. Complex II and succinate dehydrogenase were not affected by DSS, as protein carbonyl content. Conclusions:, It is speculated that NAC and DFX might be useful for treatment of colitis, but further research is necessary to clarify these effects. [source] Inhibition of ascorbic acid-induced modifications in lens proteins by peptidesJOURNAL OF PEPTIDE SCIENCE, Issue 3 2003Mariana Argirova Abstract The effects of three dipeptides L -phenylalanyl-glycine, glycyl- L -phenylalanine, and aspartame (L -aspartyl- L -phenylalanine, methyl ester) as inhibitors of the ascorbic acid-induced modifications in lens proteins were studied. Their efficiency was compared to that of two known inhibitors,aminoguanidine and carnosine. The tested dipeptides diminished protein carbonyl content by 32,58% and most moderated the formation of chromophores, as measured by the absorbency at 325 nm of the glycated proteins. The appearance of non-tryptophan fluorescence (excitation 340 nm/emission 410 nm) was observed for proteins glycated with ascorbic acid. All of the dipeptides examined, as well as aminoguanidine, decreased this glycation-related fluorescence. The potential inhibitors prevented the intensive formation of very high molecular weight aggregates. A competitive mechanism of their inhibitory effect was proposed, based on the reactivity of individual substances toward ascorbic acid. These findings indicate that they have a potential for use as alternatives for aminoguanidine as an anti-glycation agent. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd. [source] Gastroprotective properties of Myristica malabarica against indometacin-induced stomach ulceration: a mechanistic explorationJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2007Debashish Banerjee The healing activity of the methanol extract of the spice rampatri, Myristica malabarica, (RM) and omeprazole against indometacin-induced stomach ulceration has been studied in a mouse model. Treatment with RM (40 mg kg,1 per day) and omeprazole (3 mg kg,1 per day) for 3 days could effectively heal the stomach ulceration, as revealed from the ulcer indices and histopathological studies. Compared with the ulcerated group, treatment with RM and omeprazole for 3 days reduced the macroscopic damage score by approximately 72% and 76%, respectively (P < 0.001), establishing the efficacy of RM. The extent of ulcer healing offered by 3 days' treatment with RM or omeprazole was better than that observed with natural recovery over 5 and 7 days (P < 0.05). The healing capacities of RM and omeprazole could be attributed to their antioxidant activity as well as the ability to enhance the mucin content of the gastric tissues. Both drugs reduced lipid peroxidation (by 42,44%) and protein carbonyl content (by 34%), and augmented non-protein thiol levels beyond normal values. Furthermore, RM improved the mucin level beyond the normal value, while omeprazole restored it to near normalcy. [source] Concentration-dependent effect of (,) epicatechin in hypertensive patientsPHYTOTHERAPY RESEARCH, Issue 10 2010Navneet Kumar Abstract Non-vitamin polyphenolic compounds are ubiquitous in food plants and therefore potentially present in human plasma in a diet-dependent concentration. The aim of this study was to evaluate the concentration-dependent effect of (,) epicatechin, a polyphenol present in green tea with antioxidant activity, on various biomarkers of oxidative stress. The current study examined the in vitro concentration-dependent (10,4,M to 10,7,M) effects of (,) epicatechin on biomarkers of oxidative stress viz. malondialdehyde (MDA), reduced glutathione (GSH), membrane sulfhydryl (-SH) group and protein carbonyl content in hypertensive patients and normal ones. This effect seems to be due to ability of (,) epicatechin to reduce MDA and protein carbonyl content while increase in GSH and membrane -SH group in hypertensive patients. It can be concluded that (-) epicatechin exerts an antioxidant action inside the cell, responsible for the observed modulation of cellular response to oxidative challenges. Copyright © 2010 John Wiley & Sons, Ltd. [source] Oxidative Damage of Biomolecules in Mouse Liver Induced by Morphine and Protected by AntioxidantsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2004Yun-Tao Zhang The oxidative damage of DNA as measured by single cell electrophoresis and high-performance liquid chromatography equipped with electrochemical and UV detection, the protein carbonyl content was measured by 2,4-dinitrophenylhydrazine method, and the malondialdehyde content was measured by the HPLC method. The activities of antioxidative enzymes, superoxide dismutase, catalase and glutathione peroxidase, and the activity of alanine aminotransferase were assayed by spectrophotometer method. Glutathione and oxidized glutathione were detected by fluorescence spectrophotometer method. All the indexes of oxidative damage, such as 8-OHdG, protein carbonyl group and malondialdehyde content, and the activity of alanine aminotransferase (n=27) increased significantly compared to those of control (n=27) (P<0.01) in livers of morphine-administered alone mice, while the indexes related with the in vivo antioxidative capacity, such as the ratio of glutathione and oxidized glutathione, activities of superoxide dismutase, catalase and glutathione peroxidase significantly decreased (P<0.01). When mice were treated with morphine combined with exogenous antioxidants, glutathione and ascorbic acid, all the indexes of oxidative damage and the activity of alanine aminotransferase showed no changes as compared to those of control (P>0.05), i.e., both glutathione and ascorbic acid completely abolished the damage of morphine on the hepatocyte. These results implied that morphine caused a seriously oxidative stress in mice livers and hence caused hepatotoxicity, while exogenous antioxidants were able to prevent the oxidative damage of biomolecules and hepatotoxicity caused by morphine. Thus, blocking oxidative damage may be a useful strategy for the development of a new therapy for opiate abuse. [source] Is correction for protein concentration appropriate for protein adduct dosimetry?CANCER SCIENCE, Issue 2 2007Hypothesis, clues from an aflatoxin B1-exposed population Protein adducts are useful biomarkers for assessing exposure, metabolism and risk of carcinogens. Aflatoxin B1,albumin adducts (AAA) and protein carbonyl content (PCC) have long been used for assessing aflatoxin exposure and oxidative stress to proteins, and the quantitative data are almost exclusively expressed per mg protein. Given the large variation in protein concentrations in plasma among populations, this may not be the most appropriate method. The objective was to test the hypothesis that AAA and PCC should be expressed per mL plasma in population studies. AAA and PCC were analyzed among 402 subjects from three regions of China with a gradient in hepatocellular carcinoma (HCC) mortality ranging from 21 to 97 per 100 000. When biomarker values were expressed per mL plasma, the AAA level was significantly associated with plasma PCC (r = 0.262, P < 0.001), and adjusted levels of AAA and PCC paralleled HCC mortalities in the three regions, suggesting a role for aflatoxin-related oxidative stress in hepatocarcinogenesis in this population. In addition, there were statistically significant associations between both protein biomarkers, expressed per mL plasma, and the levels of alanine aminotransferase and aspartate aminotransferase in hepatitis B virus-infected subjects, suggesting roles for aflatoxin exposure, oxidative stress and hepatitis B virus infection in the development of HCC. The present data suggest that interindividual variation in plasma protein concentration may influence the dosimetry and relevant interpretation of protein biomarkers. (Cancer Sci 2007; 98: 140,146) [source] | ||||||||||||||||