Changes In Malondialdehyde Content Research Articles

Transgenic Alfalfa with GsPPCK1 and Its Alkaline Tolerance Analysis

Environmental stresses, such as drought, high salty and alkali, adversely affect plant growth and productivity. Plants adapt to these environmental stresses by inducing numerous genes at the transcriptional level and by protein phosphorylation. Phosphoenolpyruvate carboxylase kinase (PPCK) is a Ca2+ independent kinase in response to a range of signals in different plant tissues which plays a key role in the control of plant metabolism. As an important extension of our earlier studies summarized above on global transcriptome profiling of wild soybean under NaHCO3 treatment, an alkaline (NaHCO3) related gene GsPPCK1 was identified and subsequently cloned from Glycine soja, which has 99% similarity with PPCK1 of Glycine max (AAQ83695.1), named as GsPPCK1. Expression of GsPPCK1 mRNA was induced by NaHCO3 stress in roots and leaves. GsPPCK1 transcripts increased during 3 hour exposures to NaHCO3 stress. These results indicated that wild soybean PPCK1 was an early responded gene to alkaline stress. We transformed GsPPCK1 gene into alfalfa using a developed method, and transgenic alfalfa showed observably enhanced tolerance to NaHCO3 stress compared with wild-type plants. Transgenic alfalfa grew well in the conditions of 100 mmol L–1 NaHCO3 , while wild type plants exhibited discoloration and stunted growth, or even death. There were significantly changes in malondialdehyde content and relative membrane permeability caused by saline-alkaline stress in non-transgenic lines compared to transgenic lines (P0.05). Moreover, compared with non-transgenic, transgenic alfalfa had higher levels of chlorophyll content and root activity under alkali stress conditions. The result indicated that over-expression of GsPPCK1 in alfalfa could enhance alkaline tolerance. All results showed that GsPPCK1 gene could improve the tolerance of transgenic alfalfa to alkali stress; therefore, the study on this field is of significance not only in theory but also in practice.

Over-expressing GsGST14 from Glycine soja enhances alkaline tolerance of transgenic Medicago sativa

Glutathione-S-transferases (GSTs) are ubiquitous enzymes that play a key role in stress tolerance and cellular detoxification. The GST gene GsGST14 selected from the gene expression profiles of Glycine soja under alkaline stress was transformed into alfalfa (Medicago sativa L.). Transgenic alfalfa plants showed 1.73–1.99 times higher GST activity than wild-type plants. Transgenic alfalfa grew well in the presence of 100 mM NaHCO3, while wild-type plants exhibited chlorosis and stunted growth, even death. There were marked changes in malondialdehyde content and relative membrane permeability caused by alkaline stress in non-transgenic lines compared to transgenic lines. The results indicate that the gene GsGST14 could enhance alkaline resistance in transgenic alfalfa.

Over-expressing GsGST14 from Glycine soja enhances alkaline tolerance of transgenic Medicago sativa

Glutathione-S-transferases (GSTs) are ubiquitous enzymes that play a key role in stress tolerance and cellular detoxification. The GST gene GsGST14 selected from the gene expression profiles of Glycine soja under alkaline stress was transformed into alfalfa (Medicago sativa L.). Transgenic alfalfa plants showed 1.73-1.99 times higher GST activity than wild-type plants. Transgenic alfalfa grew well in the presence of 100 mM NaHCO3, while wild-type plants exhibited chlorosis and stunted growth, even death. There were marked changes in malondialdehyde content and relative membrane permeability caused by alkaline stress in non-transgenic lines compared to transgenic lines. The results indicate that the gene GsGST14 could enhance alkaline resistance in transgenic alfalfa.

Effects of polycyclic aromatic hydrocarbons exposure on antioxidant system activities and proline content in Kandelia candel

Abstract The antioxidant system effects of Kandelia candel were investigated under four different levels of PAH stress. The activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), the responses to the change of malondialdehyde (MDA) contents and the accumulation of proline in K. candel were determined. Our results suggested that the activities of SOD, CAT, POD increased significantly in leaves and roots of K. candel (p≤0.05) with the increase of the external PAH concentrations, while in stems, the activities of these antioxidant enzymes were all significantly inhibited (p≤0.01). We also observed an increase of MDA in leaves, stems and roots, and an obvious correlation between MDA content and PAH concentrations in three locations, which showed that the change of MDA content could be used as a biomarker of K. candel under PAH stress. The proline content was found remarkably enhanced in leaves, stems and roots. However, a significant inverse correlation was observed between the proline content and SOD (r=−0.99, p≤0.01), POD (r=−0.95, p≤0.05) activities in stems. This study suggested that the antioxidative system of K. candel has an obvious organ-dependent feature when exposed to PAH contamination as revealed by discriminant analysis (DA).

Biochemical effects of acute phoxim administration on antioxidant system and acetylcholinesterase in Oxya chinensis (Thunberg) (Orthoptera: Acrididae)

The study was undertaken to evaluate the effects of different concentrations of phoxim on acetylcholinesterase (AChE) and esterase (EST) activities, and antioxidant system after topical application to Oxya chinensis. The results showed that phoxim inhibited AChE activity, and did not cause significant changes in the EST activity and the levels of malondialdehyde (MDA) and reduced glutathione (GSH). After phoxim administration, superoxide (SOD) and catalase (CAT) activities showed a biphasic response with an initial increase followed by a decline in their activities. Glutathione reductase (GR) and glutathione peroxidase (GPx) activities were inhibited in comparison with the control. Glutathione S-transferase (GST) activity showed irregular changes. Its activity increased significantly at the concentrations of 0.06 and 0.12 μg/μL and decreased at the concentrations of 0.09 and 0.24 μg/μL compared with the control. Changes in SOD, CAT, GST, GPx, and GR activities indicated that phoxim caused oxidative damage in O. chinensis. However, no significant changes in MDA content suggested that these enzymes played important roles in scavenging the oxidative free radicals induced by phoxim in O. chinensis. The formation of oxygen free radicals might be a factor in the toxicity of phoxim.

Accumulation of Lignin and Malondialdehyde in Relation to Quality Changes of Button Mushrooms (Agaricus bisporus) Stored in Modified Atmosphere

Whole fresh button mushrooms (Agaricus bisporus) were stored in unsealed bags in two types of modified atmosphere packaging (MAP), namely, active and passive, at 4 °C. The packaging film was 0.04 mm low-density polyethylene and the gas composition of the active MAP was 12% O(2), 2.5% CO(2) and 85.5% N(2). Firmness of Mushroom showed a positive correlation with the accumulation of lignin in the tissue. On the other hand, changes of malondialdehyde content with storage time were proportional to the evolution of browning. The button mushrooms in control treatment developed severe browning at the end of the 15-day storage, while the mushrooms of both active and passive MAP treatments browned slightly. MAP treatments could not inhibit phenylalanine ammonia lyase activity; however, it can reduce the lignification process by the inhibition of peroxidase (POD) activity and the accumulation of lignin. Correlation between the cinnamyl alcohol dehydrogenase activity and lignin accumulation was not obvious. Our results suggested that an increase in the firmness of mushrooms during senescence may be a consequence of tissue lignification, a process associated with increase in POD activity. Both active and passive MAPs were useful for the conservation of tenderness and whiteness in button mushrooms.

Biochemical and physiological changes in jack bean under mycorrhizal symbiosis growing in soil with increasing Cu concentrations

The influence of jack bean [ Canavalia ensiformis (L.) D.C.] mycorrhization, by the arbuscular mycorrhizal (AM) fungus Glomus etunicatum, in response to increasing Cu concentrations in soil (0, 50, 150 and 450 mg dm −3) was studied. In the highest Cu dose, mycorrhiza decreased Cu concentrations in plant organs and promoted biomass accumulation. In addition, mycorrhizal colonization was not affected by Cu suggesting certain tolerance of the inoculated AM fungus to this metal. Cu-induced proline accumulation and an increase in soluble amino acid contents in leaves, with higher proline contents in AM plants. Marked differences in foliar soluble amino acid composition were also observed in response to Cu in the soil. The activity of key antioxidant enzymes increased mainly in the leaves of non-AM plants, indicating increased production of reactive oxygen species. However, changes in malondialdehyde content were not observed suggesting an effective antioxidant system. Independent of mycorrhization, glutathione content in leaves decreased as Cu increased in the soil. Phytochelatins were detected in the leaves of both Cu treated and untreated plants, and quantitative and qualitative differences were observed due to mycorrhization. In summary, the AM fungus was able to maintain an efficient symbiosis with jack bean plants in soil containing high Cu concentrations. A combination of physiological and nutritional changes caused by the symbiotic association that might be of interest for phytoremediation strategies in Cu-contaminated soils.

Induction of heat tolerance in wheat coleoptiles by calcium ions and its relation to oxidative stress

Effects of Ca2+ ions on the intensity of lipid peroxidation, activities of guaiacol peroxidase, superoxide dismutase (SOD), and catalase, as well as on heat resistance of winter wheat (Triticum aestivium L.) coleoptiles were examined. A preliminary incubation of coleoptile segments in a 5 mM CaCl2 solution was shown to improve their survival rates after an injuring heat treatment (43.5°C). The effect of Ca2+ was suppressed by the inhibitor of Ca2+ channels (1 mM LaCl3). An incubation of coleoptiles in the presence of 5 mM CaCl2 prior to the stress treatment elevated the content of lipid peroxidation product, malondialdehyde (MDA) and stimulated the activities of guaiacol peroxidase, SOD, and catalase. After the heat exposure of untreated and Ca2+-treated seedlings, differential changes in MDA content and in activities of guaiacol peroxidase, SOD, and catalase were observed. It is concluded that a short-term oxidative stress arising in Ca2+-enriched plant tissues after the heat treatment is unrelated to their irreversible damage.

The effects of oxidative stress on the liver sieve

Background/Aims Oxidative stress is implicated in the pathogenesis of age-related and disease-associated changes in the hepatic sinusoid. We studied the effects of oxidative stress on the morphology of the liver, focusing specifically on the hepatic sinusoidal endothelium (the ‘liver sieve’). Methods The effects of tert-butyl hydroperoxide on the intact liver and isolated sinusoidal endothelial cells were assessed by electron microscopy, immunohistochemistry and biochemical analysis. Results Immunohistochemistry revealed a dose-dependent increase in peri-sinusoidal 3-nitrotyrosine staining, particularly in the regions adjacent to the portal triads. Electron microscopy showed dose-dependent formation of large intracellular gaps in the sinusoidal endothelium with reduction in the diameter of the remaining endothelial fenestrations. Activated Kupffer cells extending processes through the fenestrations to contact hepatocytes were noted. Biochemical analysis of total liver tissue showed no significant changes in malondialdehyde content but a decrease in the ratio of GSH to GSSG. tert-Butyl hydroperoxide administered directly onto isolated liver sinusoidal endothelial cells was associated with similar gap formation, indicating a direct effect on the endothelial cells by tert-butyl hydroperoxide. Conclusions Oxidative stress selectively damages hepatic sinusoidal endothelial cells. This has implications for those processes associated with changes in the sinusoidal endothelium such as ageing, cirrhosis and exposure to hepatotoxins.

Responses of Xanthoria parietina thalli to environmentally relevant concentrations of hexavalent chromium.

Thalli of the lichen Xanthoria parietina (L.) Th. Fr. were soaked for either 24 or 48 h in a buffered medium in the presence of environmentally relevant concentrations (4.8 and 9.6 μM) of hexavalent chromium [Cr(VI)]. Treatment effects on the antioxidant status, differential distribution and fate of Cr(VI) among the mycobiont and the photobiont cells, and potential damage to cell ultrastructure in the two bionts, were evaluated. The adopted conditions of low Cr(VI) stress caused: (i) an increase in the level of ascorbic acid and a decrease in that of reduced glutathione, as well as a moderate increase in guaiacol peroxidase activity, only observed after treatment with 9.6 μM Cr(VI); (ii) no changes in malondialdehyde content; (iii) a remarkable Cr accumulation in the mycobiont cytosol and compartmentalisation in the mycobiont vacuoles;(iv) a modest apoplastic Cr immobilisation by the outer part of the cell walls, of both the mycobiont and the photobiont. The response of X.parietina to low concentrations of Cr(VI) appears to be a complex phenomenon, which might reflect maintenance of cellular homeostatic equilibria, rather than specific response pathways.

Changes in the antioxidant enzyme efficacy in two high yielding genotypes of mulberry ( Morus alba L.) under NaCl salinity

Changes in the activity of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), peroxidase (POD: EC 1.11.1.7), catalase (CAT: EC 1.11.1.6), glutathione reductase (GR: EC 1.6.4.2), glutathione S-transferase (GST: EC 2.5.1.18), cell membrane stability (CMS) and the rate of lipid peroxidation in terms of malondialdehyde (MDA) content in two high yielding genotypes (S1 and ATP, salt tolerant and salt susceptible, respectively) of mulberry under NaCl salinity were studied. After salt stress, antioxidative enzymes were altered in mulberry and the extent of alteration varied between the cultivar S1 and ATP, leading to the higher amounts of antioxidative enzymes in S1 supporting its salt tolerance. The levels of lipid peroxidation as indicated by MDA formation was high in the sensitive variety (ATP), while the tolerant variety (S1) showed no change in MDA content under NaCl salinity. Further, the salt tolerance of S1 was supported by CMS, having comparatively lower amounts of electrolyte leakage. The relative tolerance of these two cultivars is discussed.

The Effect of Quinacrine on Oxidative Stress in Kidney Tissue Stored at Low Temperature after Warm Ischemic Injury

Rabbit kidney cortex tissue slices were made ischemic (37°C) for 60 min and then either reperfused in warm (37°C) oxygenated physiologic buffer for 210 min or placed in UW Na gluconate solution (± quinacrine; 100 μmol/L) for 18 h followed by warm aerobic reperfusion. Slices were sampled at intervals and analyzed for malondialdehyde (MDA) content by HPLC. Control (nonischemic) slices had no change in MDA content over the duration of the experiment. Hypothermic storage of nonischemic slices did not result in any increase in MDA during reperfusion. Ischemic slices showed significant increases in MDA content during the first 1.5 h of reperfusion and remained elevated for the remainder of the experiment. Hypothermic storage of warm ischemic kidney slices resulted in a significant decrease in MDA content during the storage period. However, MDA content in these slices increased during warm reperfusion and was significantly higher than that in nonischemic controls. Quinacrine added during hypothermic storage of warm ischemic slices significantly decreased slice MDA content during warm reperfusion, an effect which was lost by increasing the storage solution calcium content. This study shows that aerobic hypothermic storage can aid in reducing oxidative stress in warm ischemic kidney tissue during reperfusion. This study suggests that the effects of quinacrine are at the level of the mitochondrion and not as an antioxidant compound.

Effect of angiotensin convertase inhibitors on lipid peroxidation and peroxyl radical-trapping capacity in rats with experimental diabetes.

Effect of two angiotensin convertase inhibitors, enalapril and captopril, on blood plasma and erythrocyte lipid peroxidation and plasma peroxyl radical-trapping capacity was studied in rats with streptozotocin-induced diabetes. A progressive increase in blood erythrocyte malondialdehyde (MDA) level was observed in diabetic rats after 6 and 12 weeks. Blood plasma MDA level increased while plasma peroxyl radical-trapping capacity was decreased after 12 weeks. Captopril (2 mg/kg body weight) augmented the diabetes-induced changes in MDA content after 6 weeks and prevented them after 12 weeks increasing also the peroxyl radical-trapping capacity. Enalapril (1 mg/kg body weight) counteracted the diabetes-induced changes in MDA content after both 6 and 12 weeks but did not affect the plasma peroxyl radical-trapping capacity. These results suggest a possibility of a therapeutic use of angiotensin convertase inhibitors to attenuate the effects of oxidative stress in diabetes.

Changes in malondialdehyde content and in superoxide dismutase, catalase and glutathione reductase activities in sunflower seeds as related to deterioration during accelerated aging

Sunflower (Helianthus annuus L.) seeds progressively lost their ability to germinate at 25°C, the optimal temperature for germination, after accelerated aging was carried out at 45°C (a temperature too high to permit germination) in water or at 76 or 100% relative humidity (RH). The deleterious effects of the high‐temperature treatment increased with increasing seed moisture content. Incubation of seeds at 45°C in water resulted in electrolyte leakage, which indicated a loss of membrane integrity. A relationship between leakage and loss of seed viability could not be assumed, since no increase in electrolyte efflux occurred after aging al 100% RH. Accelerated aging induced accumulation of malondialdehyde, suggesting that seed deterioration was associated with lipid peroxidation. However, there was no direct relationship between lipid peroxidation and deterioration in membrane integrity. Loss of seed viability was also associated with a decrease in superoxide dismutase, catalase and glutathione reductase activities. Finally, the results obtained suggest that sunflower seed deterioration during accelerated aging is closely related to a decrease in the activities of detoxifying enzymes and to lipid peroxidation.

Changes in malondialdehyde content and in superoxide dismutase, catalase and glutathione reductase activities in sunflower seeds as related to deterioration during accelerated aging

Changes in malondialdehyde content and in superoxide dismutase, catalase and glutathione reductase activities in sunflower seeds as related to deterioration during accelerated aging

Contribution of Leukocyte Infiltration to Lipoperoxidation Occurring in the Non-Ischemic Region of the Rat Heart Submitted to Permanent Left Coronary Artery Occlusion

Previous studies have shown that during regional myocardial ischemia, the non-ischemic zone may be submitted to metabolic and structural alterations. In the present study, we have examined whether an inflammatory process could be responsible for increased lipoperoxidation in the non-ischemic zone of the rat heart subjected to permanent coronary artery ligation. Forty-eight hours after coronary artery ligation, tissue levels of malondialdehyde (MDA), taken as an index of lipoperoxidation, measured in the non-ischemic zone was increased by 25% when compared to sham operated hearts. Furthermore, an infiltration of polymorphonuclears was observed by immunofluorescence in the non-ischemic zone, while the activity of the neutrophil-specific myeloperoxidase enzyme (MPO) was significantly increased in that same zone (ligated 1.26 ± 0.17 U/100 mg wet wt. v sham 0.33 ± 0.01 U/100 mg wet wt.; P < 0.01). Examination of the temporal changes in MDA content and of MPO activity showed a significant linear decrease in both parameters of 6 to 48 h post-ligation. When compared to placebo, treatment with indomethacin (1 mg/kg, 5 min prior to ligation, then at 12 h intervals up to the harvesting of the hearts) led to a significant reduction in MDA content measured 6.24 or 48 h after ligation. The treatment had no effect on infarct size measured 48 h after ligation. These results suggest that in the rat heart, permanent regional ischemia is associated with the rapid development of an inflammatory process in the non-ischemic zone which could in part account for the accumulation of lipoperoxidation products in that region.

Antioxidant changes in heart hypertrophy: significance during hypoxia-reoxygenation injury.

Because hypertrophied rat hearts display an increase in antioxidant enzyme activities and because hypoxia-reoxygenation injury is known to involve free radicals, we tested the hypothesis that the hypertrophied heart may be more resistant to this type of injury. Hypertrophied rat hearts after 10 weeks of chronic pressure overload showed elevated superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities and a decrease in lipid peroxidation as indicated by malondialdehyde (MDA) content. Glucose-free hypoxia for 15 min resulted in a complete failure of developed tension and about 200% increase in resting tension in both hypertrophied and sham control groups (p < 0.05). Upon reoxygenation for up to 30 min, hypertrophied hearts recovered developed tension to 60% and resting tension was higher by only 80% of prehypoxic values. In contrast, sham hearts showed only a 25% recovery of developed tension, whereas resting tension remained 130% higher than prehypoxic control values. During hypoxia, the SOD activity was significantly reduced in both sham and hypertrophied groups, whereas GSHPx was reduced only in the sham group. Upon reoxygenation there was no further change in these enzyme activities. Both the SOD and GSHPx activities in the hypertrophied group remained significantly higher than the corresponding reoxygenated sham hearts. During hypoxia, there was no apparent change in MDA content in either the sham or hypertrophied hearts. However, reoxygenation resulted in a significant increase in MDA content in both sham and hypertrophied hearts, but the MDA content was significantly less in the hypertrophied group (p < 0.05). It is suggested that maintenance of an adequate endogenous antioxidant reserve during hypoxia may be important in recovery upon reoxygenation.

Kinetics of oxygen metabolism indices in the course of histamine secretion from rat mast cells

In this study data are presented on the kinetics of changes in malondialdehyde content (MDA), lipoxygenase activity (LO), superoxide dismutase activity (SOD), glutathione peroxidase activity (GSH-Px) and glutathione reductase activity (GSSG-Red) during the course of histamine secretion from rat mast cells. Both receptor-mediated (antigen, polymyxin B, compound 48/80) and non-receptor (the calcium ionophore A23187) stimuli of mast cell activation were investigated. A similar alteration in all the studied indices was observed after challenge with receptor-mediated stimuli. The earliest event was a decrease in SOD-activity, which coincided with the increase in histamine secretion. SOD-activity then gradually increased above the baseline levels. Similar changes in GSSG-Red- and GSH-Px-activities were also observed. The increase in MDA content occurred slightly later. Challenge with the calcium ionophore A 23187 did not cause a reduction in SOD-activity, only the increase in activity was observed. Histamine release induced by all stimuli was accompanied by a marked elevation in enzymatic peroxidation (LO-activity). Diethyldithiocarbamate (DTC), which inhibits SOD, not only blocked the enzyme activity but also caused a dose-dependent inhibition of histamine release and an inhibition of the elevation of enzymatic peroxidation in mast cells challenged with compound 48/80.