Degradation Product Of Lipid Peroxidation Research Articles

Periodic monitoring of persistent organic pollutants and molecular damage in Cyprinus carpio from Büyük Menderes River.

Concentrations of persistent organic pollutants (POPs) were quantified in river water and sediment, as well as in the liver and muscle tissues of Cyprinus carpio that were sampled four times in a year at three stations in the Büyük Menderes River (BMR). Potential biomarkers of possible cellular molecular damage, namely lipid peroxidation (LPO) degradation products, protein carbonyls (PCO) and DNA repair product 8-hydroxy-2'-deoxyguanosine (8-OHdG), were analysed. All the targeted pollutants were measurable both in biotic and abiotic samples. Interestingly, the results suggested that there was recent organochlorine pesticide (OCP) input into the river water in the first two sampling periods in all stations in contrast to prohibition, while input of polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs) was not detected. Liver POP concentrations were higher than in muscle, as expected, and were found to decrease from the first to the fourth sampling period in all stations, except PBDEs. Levels of LPO degradation products in the liver and in muscle tissues decreased from the first to the fourth sampling period. This suggests that these markers reflect the lipid damage in respective tissues due to the tissue burden of targeted POPs. Protein carbonyls were the highest in the first sampling period, followed by a dramatic decrease in the second, and then a gradual increase towards the fourth sampling period in all stations. 8-OHdG levels were lower in Sarayköy station in the first sampling period. Among the measured biomarkers, only several LPO degradation products were significantly correlated with OCPs and PCBs in liver tissue.

Investigation of UV–TiO2 photocatalysis and its mechanism in Bacillus subtilis spore inactivation

The inactivation levels of Bacillus subtilis spores for various disinfection processes (ultraviolet (UV), TiO2 and UV–TiO2) were compared. The results showed that the inactivation effect of B. subtilis spores by UV treatment alone was far below that for bacteria without endospores. TiO2 alone in the dark, as a control experiment, exhibited almost no inactivation effect. Compared with UV treatment alone, the inactivation effect increased significantly with the addition of TiO2. Increases of the UV irradiance and TiO2 concentration both contributed to the increase of the inactivation effect. Lipid peroxidation was found to be the underlying mechanism of inactivation. Malondialdehyde (MDA), the degradation product of lipid peroxidation, was used as an index to determine the extent of the reaction. The MDA concentration surged surprisingly to 3.24nmol/mg dry cell with the combination disinfection for 600sec (0.10mW/cm2 irradiance and 10mg/L TiO2). In contrast, for UV alone or TiO2 in the dark, the MDA concentration was 0.38 and 0.25nmol/mg dry cell, respectively, under the same conditions. This indicated that both UV and TiO2 were essential for lipid peroxidation. Changes in cell ultrastructure were observed by transmission electron microscopy. The cell membrane was heavily damaged and cellular contents were completely lysed with the UV–TiO2 process, suggesting that lipid peroxidation was the root of the enhancement in inactivation efficiency.

Effect of temperature on oxidative stress in fish: Lipid peroxidation and catalase activity in the muscle of juvenile seabass, Dicentrarchus labrax

The aim of this study was to investigate the effect of temperature on oxidative stress in fish. The response of the European seabass, Dicentrarchus labrax, was investigated through a long-term experiment in captivity, where 0-group juveniles were exposed to temperatures that reflect the average summer temperature that they encounter in coastal (18°C) and estuarine nurseries (24°C), and also the temperature that they endure inside estuaries during heat waves (28°C). The degradation product of lipid peroxidation, malondialdehyde (MDA), and catalase activity was assessed in white muscle throughout the long-term experiment (30 days). A similar pattern was observed for MDA and catalase activity. At 18°C, there was an increase of MDA and catalase activity over time. At 24°C, levels of MDA and catalase activity were lower than at 18°C, and the increase in concentration over time was also lower. At 28°C, MDA and catalase increased 2.7× and 6.9×, respectively, after 15 days, and then decreased to much lower values after 30 days. Oxidative stress response was not directly correlated to temperature. It was lowest at the optimal temperature (24°C) and it increased outside this species upper and lower optimum thermal limits. It was concluded that, although these biomarkers have been used mostly as indicators of the effects of contamination in field studies, they are very sensitive to temperature. Thus, comparison of sites subjected to different thermal regimes should be done with caution.

Oxidative damages of maize seedlings caused by exposure to a combination of potassium deficiency and salt stress

Soil salinity results in nutrient imbalances and potassium deficiency. However, very little work has been done on the damages of maize caused by exposure to a combination of potassium deficiency and salt-stress. Thus the influences of the combined stresses on the antioxidative defense system in maize seedlings were investigated. It was found that the growth of maize seedlings cultivated in a combination of potassium deficiency and salt stress was significantly inhibited, the compatible solute accumulation, permeability of plasma membrane, malondialdehyde as a degradation product of lipid peroxidation, reactive oxygen species such as superoxide radicals, hydrogen peroxide were higher than those of the individual potassium deficiency or salt-stress as expected. However, the antioxidative enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and antioxidants such as ascorbic acid and glutathione were lower than those of the individual potassium deficiency or salt-stress. Taken together, salt stress impairs K nutrition of maize seedlings, K deficiency at the cellular level might be a contributory factor to salt-induced oxidative stress and related cell damage.

Influence of Lanthanides on the Antioxidative Defense System in Maize Seedlings Under Cold Stress

The influence of LaCl(3), CeCl(3), and NdCl(3) on the antioxidative defense system in maize seedlings under cold stress was investigated. It was found that maize seedlings cultivated in cold stress developed distinct cold symptoms, and the plant growth was significantly inhibited as expected, while Ln-treated seedling growth was improved. Cold stress in maize seedlings also increased the permeability of plasma membrane, malondialdehyde as a degradation product of lipid peroxidation, and reactive oxygen species such as superoxide radicals and hydrogen peroxide, and decreased activities of the antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, and glutathione content; however, Ln treatments cultivated in cold stress decreased the permeability of plasma membrane, malondialdehyde, and reactive oxygen species, and increased activities of the antioxidative defense system. It implied that Ln could increase oxidative-stress resistance under cold stress. On the other hand, the assay of physiological and biochemical parameters demonstrated that Ce relieving chilling injury of maize seedlings caused by cold stress was most significant, medium in the Nd treatment, and last in the La treatment. These results suggested that the increase of cold resistance of maize seedlings caused by Ln might be closely related to its properties of 4f electron shell and variable valence.

Cerium under calcium deficiency—influence on the antioxidative defense system in spinach plants

The influence of calcium-deficiency and cerium addition on the antioxidative defense system in spinach leaves was investigated. It was found that spinach cultivated in calcium-deficiency media developed distinct calcium deficiency symptoms and the plant growth was significantly inhibited as expected. While cerium-treated spinach remained green and expanded, and plant growth was improved. Calcium deprivation in spinach also increased the permeability of plasma membrane, malondialdehyde as a degradation product of lipid peroxidation, reactive oxygen species such as superoxide radicals, hydrogen peoxide, and decreased activities of the antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase and glutathione content. However, cerium treatment cultivated in calcium-deficiency media decreased the permeability of plasma membrane, malondialdehyde and reactive oxygen species, and increased activities of the antioxidative defense system. This is viewed as evidence for cerium addition to calcium-deficiency media in the spinach plants could substitute calcium and enhance oxidative stress-resistance.

Analyses of representative biomarkers of exposure and effect by chromatographic, mass spectrometric, and nuclear magnetic resonance techniques: Method development and application in life sciences

Biomarkers are essential tools in monitoring studies, which include environmental monitoring, biological monitoring, biological effect monitoring, and health surveillance, as well as drug development processes. Their discovery, validation, and analysis require highly sensitive and selective analytical technologies. In this regard, gas and liquid chromatography, mass spectrometry, and nuclear magnetic resonance spectroscopy have facilitated great achievements in all these areas. In addition and closely related to biomarkers, the ongoing developments in these techniques promise a better understanding of the nature and mechanisms of toxic effects originating from various chemical, biological, or physical sources. This Review compiles studies performed on selected biomarkers with respect to both method development and application. Section 1 summarizes the concept of biomarkers; their application in various industrial/occupational, agricultural, drug developmental, and medical/clinical platforms. This section also focuses on biotransformation studies in close relation to biomarker discovery and validation, and on major techniques utilized in this area. In Section 2, biotransformation of volatile anesthetics in humans with a focus on mercapturic acid derivatives as potential biomarkers of effect is reviewed. The use of GC-ECD, GC/MS, and 19F-NMR in these studies is described. Section 3 focuses on the analysis of aldehydic lipid peroxidation degradation products by GC-ECD in mammalian cells in which oxidative stress induced chemically, and in humans after various challenges; anesthetic exposure, ischemia-reperfusion, and controlled endurance exercise. In Section 4, method development for protein and DNA oxidation products by LC-tandem MS and its application in mammalian cells and in humans are summarized. Possibilities, limitations, and future perspectives are discussed in Section 5.

Application of lipid peroxidation and protein oxidation biomarkers for oxidative damage in mammalian cells. A comparison with two fluorescent probes

We recently developed two biomarker sets for oxidative damage: one for determination of lipid peroxidation (LPO) degradation products; acetaldehyde, propanal, butanal, pentanal, hexanal, heptanal, octanal, nonanal, malondialdehyde and acetone, by a gas chromatography-electron capture detection method, and the other for protein oxidation products such as o, o′-dityrosine, by an isotope dilution high performance liquid chromatography–tandem mass spectrometry method. In the present study, we explored the possibility to utilize these biomarkers for determining the oxidative damage in liver mammalian cells in vitro. Two different treatments were chosen for inducing oxidative stress in Chinese Hamster ovary cells: menadione and copper plus hydrogen peroxide (Cu 2+/H 2O 2). Cells were incubated with the model compounds in the presence or absence of vitamin E and C, and cytotoxicity was evaluated by a nuclear-dye method. Results were compared to two fluorescent probes, H 2DCF-DA and C 11-BODIPY 581/591, which have been used for determining the formation of free radicals in the cells. From ten LPO degradation products, eight were increased significantly following incubation with menadione in cell lysate or incubation media. Menadione-induced oxidative stress was also confirmed by oxidation of fluorescent probes. However, no increased formation of protein oxidation products was observed. Vitamin E and C did not diminish the formation of LPO degradation products that were increased by menadione. Although Cu 2+/H 2O 2 did not induce oxidation of fluorescent probes, it induced formation of six out of ten LPO degradation products. Vitamin E and C did not diminish the formation of LPO degradation products; vitamin C even substantially increased the formation of acetaldehyde and propanal, which is in line with its reported prooxidant action under certain conditions. Vitamin C also caused two-fold increase in Cu 2+/H 2O 2-induced o, o′-dityrosine formation when applied simultaneously. In conclusion, our present results show that the LPO biomarker set can be used for evaluation of oxidant capacity and the toxic potential of various chemicals in an in vitro cell model. These biomarkers might even be more sensitive than measuring protein oxidation products or oxidation of fluorescent probes.

Fragmentation study of short‐chain products derived from oxidation of diacylphosphatidylcholines by electrospray tandem mass spectrometry: identification of novel short‐chain products

Lineloyl-palmitoyl (PLPC) and arachidonoyl-palmitoyl (PAPC) phosphatidylcholine were oxidized under Fenton reaction conditions (H2O2 and Fe2+), and the short-chain products formed were identified by electrospray ionization mass spectrometry (ESI-MS). The short-chain products resulted from beta-cleavage of oxygen-centered radicals and comprised aldehydes, hydroxyaldehydes and dicarboxylic acids that yielded both [MH]+ and [MNa]+ ions. The fragmentation of the [MH]+ and [MNa]+ ions of the peroxidation products was studied by tandem mass spectrometry (MS/MS). The MS/MS spectra of both ions showed ions resulting from characteristic losses of glycerophosphatidylcholine. Other product ions, resulting from C-C cleavages occurring in the vicinity of the functional group, and fragmentations involving the hydroxy groups, were the most informative since they allowed us to obtain structural information relating to the sn-2 acyl residue. Both fragmentation pathways are due to charge-remote fragmentation occurring by a 1,4-hydrogen elimination mechanism and/or by homolytic cleavage. Furthermore, the fragmentation pathway of some ions observed in the ESI-MS spectrum was not consistent with the fragmentation behavior expected for some of the short-chain species identified in the literature and allowed the reassignment of the ions as different structures. Isobaric ions were observed in the ESI-MS spectra of both oxidized phospholipids, and were differentiated based on distinct fragmentation. The detailed knowledge of lipid peroxidation degradation products is of major importance and should be very valuable in providing new markers for oxidative stress signaling and for disease states monitoring.

Oxidative status during late pregnancy and early lactation in dairy cows

In the last few years, the detection of free radical damage and the body's defences against it have become increasingly important in clinical medicine as a complementary tool in the evaluation of metabolic status. The aim of this study was to evaluate, under field conditions, the anti-oxidant status of healthy cows during late pregnancy and lactation onset using two parameters: (1) plasma levels of malondialdehyde (MDA), a degradation product of lipid peroxidation, and (2) total antioxidant status (TAS). Results were compared with those obtained in another group of cows with lesser metabolic demands. We also investigated possible relationships between antioxidant status markers and other relevant blood parameters. Our results confirmed the characteristic metabolic changes associated with late pregnancy and early lactation. MDA and TAS provided an accurate reflection of the internal physiological status of the animal. The data indicated increased lipid peroxidation around parturition, but with wide individual variations that may be attributable not only to the physiological stage but also to unknown factors that will have to be further considered in future studies.

Calcium deficiency - Influence on the antioxidative defense system in tomato plants

Summary In this study the influence of a deficient calcium supply on the antioxidative defense system in Lycopersicon lycopersicum leaves was investigated. Trials were performed in the greenhouse employing soilless culture technique. For the induction of calcium deficiency, calcium content in the nutrient solution was reduced from 2.9 mmol/L to 0.29 mmol/L. Within 6 weeks fruits and leaves developed distinct calcium deficiency symptoms. Chlorophyll fluorescence parameters, e.g. Fm and Fv/Fm, chlorophyll and tocopherol contents dropped below control level; also, superoxide dismutase activity was reduced. Additionally, malondialdehyde as a degradation product of lipid peroxidation increased in the calcium deficient leaves. Spray application of formulated CaCl 2 solution on a weekly basis reduced blossom-end rot symptoms to about 50 percnt;. Furthermore, chlorophyll fluorescence parameters Fm and Fv/Fm as well as chlorophyll and tocopherol contents were less affected than in the calcium deficient group. No differences in malondialdehyde production could be established. SOD activity was higher in the Ca 2+ -treated leaves, while PO activity was lower compared to calcium deficient leaves.

Simultaneous determination of eight lipid peroxidation degradation products in urine of rats treated with carbon tetrachloride using gas chromatography with electron-capture detection.

One of the major processes that occur as a result of radical-induced oxidative stress is lipid peroxidation (LPO). Degradation of lipid peroxides results in various products, including a variety of carbonyl compounds. In the present study eight different lipid degradation products, i.e., formaldehyde, acetaldehyde, acetone, propanal, butanal, pentanal, hexanal and malondialdehyde were identified and measured simultaneously and quantitatively in rat urine after derivatization with O-(2,3,4,5,6-pentafluorbenzyl)hydroxylamine hydrochloride, extraction with heptane and using gas chromatography-electron-capture detection (GC-ECD). The identity of the respective oximes in urine was confirmed by gas chromatography-negative ion chemical ionization mass spectrometry (GC-NCI-MS). Simultaneously measured standard curves were linear for all oxime-products and the detection limits were between 39.0 +/- 5.3 (n=9) and 500 +/- 23 (n=9) fmol per microl injected sample. Recoveries of all products from urine or water were 73.0 +/- 5.2% and higher. In urine of CCl4-treated rats an increase in all eight lipid degradation products in urine was found 24 h following exposure. ACON showed the most distinct increase, followed by PROPA, BUTA and MDA. It is concluded that the rapid, selective and sensitive analytical method based on GC-ECD presented here is well suited for routine measurement of eight different lipid degradation products. These products appear to be useful as non-invasive biomarkers for in vivo oxidative stress induced in rats by CCl4.

Evidence for carbon tetrachloride-induced lipid peroxidation in mouse liver

The involvement of lipid peroxidation in the mechanism of carbon tetrachloride-induced hepatotoxicity has been a point of controversy. Previous investigators have reported an absence of lipid peroxidative degradation products in mice after exposure to carbon tetrachloride and have used this evidence against the hypothesis that lipid peroxidation is an integral part of the events that cause tissue damage. We have compared the extent of lipid peroxidation caused by carbon tetrachloride between Sprague-Dawley rats and three strains of mice (A/J, BALB/cJ, and C57B1/6J) in in vitro and in vivo systems. Hepatic microsomes isolated from fasted mice of each strain produced more malondialdehyde (a degradation product of lipid peroxidation) per mg microsomal protein than those isolated from fasted rats at all times of incubation with CCl 4. In vivo lipid peroxidation was estimated by the lipid conjugated diene content in hepatic microsomes from the rat and three strains of mice. Increased conjugated diene formation was observed in microsomal lipids of these animals after intraperitoneal injection of CCl 4 (1 ifml/kg as a 20% solution in corn oil) when compared to animals given only corn oil, but no differences were found in the amount of conjugated dienes between mice and rats. Our observations show that the CCl 4-treated mouse undergoes hepatic lipid peroxidation at least as well as the rat, and indicate that lipid peroxidation cannot be excluded as a mechanism of carbon tetrachloride hepatotoxicity as has been claimed on the basis of its ineffectiveness in the mouse.