scholarly journals Formation of Oxidatively Modified Lipids as the Basis for a Cellular Epilipidome

2020 ◽  
Vol 11 ◽  
Author(s):  
Corinne M. Spickett
Keyword(s):  
Biological Effects ◽  
Oxidative Modification ◽  
Oxygen Species ◽  
Radical Oxygen Species ◽  
Chemical Mechanisms ◽  
Control Gene Expression ◽  
Lipid Species ◽  
Regulatory Effects ◽  
Oxidatively Modified ◽  
The Stability

While often regarded as a subset of metabolomics, lipidomics can better be considered as a field in its own right. While the total number of lipid species in biology may not exceed the number of metabolites, they can be modified chemically and biochemically leading to an enormous diversity of derivatives, many of which retain the lipophilic properties of lipids and thus expand the lipidome greatly. Oxidative modification by radical oxygen species, either enzymatically or chemically, is one of the major mechanisms involved, although attack by non-radical oxidants also occurs. The modified lipids typically contain more oxygens in the form of hydroxyl, epoxide, carbonyl and carboxylic acid groups, and nitration, nitrosylation, halogenation or sulfation can also occur. This article provides a succinct overview of the types of species formed, the reactive compounds involved and the specific molecular sites that they react with, and the biochemical or chemical mechanisms involved. In many cases, these modifications reduce the stability of the lipid, and breakdown products are formed, which themselves have interesting properties such as the ability to react with other biomolecules. Publications on the biological effects of modified lipids are growing rapidly, supporting the concept that some of these biomolecules have potential signaling and regulatory effects. The question therefore arises whether modified lipids represent an “epilipidome”, analogous to the epigenetic modifications that can control gene expression.

scholarly journals Amino acid oxidation of the D1 and D2 proteins by oxygen radicals during photoinhibition of Photosystem II

2017 ◽  
Vol 114 (11) ◽  
pp. 2988-2993 ◽  
Author(s):  
Ravindra Kale ◽  
Annette E. Hebert ◽  
Laurie K. Frankel ◽  
Larry Sallans ◽  
Terry M. Bricker ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Amino Acid ◽  
Photosystem Ii ◽  
Light Stress ◽  
Reactive Oxygen ◽  
Nonheme Iron ◽  
Oxidative Modification ◽  
Oxygen Species ◽  
Oxidatively Modified ◽  
D1 And D2 Proteins

The Photosystem II reaction center is vulnerable to photoinhibition. The D1 and D2 proteins, lying at the core of the photosystem, are susceptible to oxidative modification by reactive oxygen species that are formed by the photosystem during illumination. Using spin probes and EPR spectroscopy, we have determined that both O2•− and HO• are involved in the photoinhibitory process. Using tandem mass spectroscopy, we have identified a number of oxidatively modified D1 and D2 residues. Our analysis indicates that these oxidative modifications are associated with formation of HO• at both the Mn4O5Ca cluster and the nonheme iron. Additionally, O2•− appears to be formed by the reduction of O2 at either PheoD1 or QA. Early oxidation of D1:332H, which is coordinated with the Mn1 of the Mn4O5Ca cluster, appears to initiate a cascade of oxidative events that lead to the oxidative modification of numerous residues in the C termini of the D1 and D2 proteins on the donor side of the photosystem. Oxidation of D2:244Y, which is a bicarbonate ligand for the nonheme iron, induces the propagation of oxidative reactions in residues of the D-de loop of the D2 protein on the electron acceptor side of the photosystem. Finally, D1:130E and D2:246M are oxidatively modified by O2•− formed by the reduction of O2 either by PheoD1•− or QA•−. The identification of specific amino acid residues oxidized by reactive oxygen species provides insights into the mechanism of damage to the D1 and D2 proteins under light stress.

scholarly journals Effect of Natural Food Antioxidants Against LDL and DNA Oxidative Changes

2018 ◽  
Author(s):  
Sotirios Kiokias ◽  
Charalampos Proestos ◽  
Vassilki Oreopoulou
Keyword(s):  
Lipid Peroxidation ◽  
Oxidative Damage ◽  
Review Paper ◽  
Oxidative Modification ◽  
Natural Food ◽  
Antioxidant Compounds ◽  
Oxygen Species ◽  
Radical Oxygen Species ◽  
Dna Oxidative Damage

Radical oxygen species formed in human tissue cells by many endogenous and exogenous pathways, cause extensive oxidative damage, which has been linked to various human diseases. This review paper provides an overview of lipid peroxidation and focuses on the free-radicals initiated processes of LDL oxidative modification and DNA oxidative damage, which are widely associated to the initiation and development of atherosclerosis and carcinogenesis, respectively. The article subsequently provides an overview of the recent human trials or even in vitro investigations on the potential of natural antioxidant compounds (such as carotenoids, vitamins C and E) to monitor LDL and DNA oxidative changes.

Characterization and functional properties of new everbearing strawberry (Fragaria x ananasa Duch.) cultivar, ‘Summertiara’ berries

2014 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
Takeshi Nagai ◽  
Misuzu Tamai ◽  
Masato Sato ◽  
Yasuhiro Tanoue ◽  
Norihisa Kai ◽  
...  
Keyword(s):  
Vitamin C ◽  
Sensory Evaluation ◽  
Functional Properties ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Antihypertensive Activity ◽  
Oxygen Species ◽  
Total Anthocyanins ◽  
Strawberry Cultivar ◽  
The Stability

Background: In recent years, a new everbearing strawberry cultivar, ‘Summertiara’ was cultivated to supply the strawberries in pre-harvest season from July to October in Japan. For highly research and development of processing of this cultivar, ‘Summertiara’ berries, the objective of this study was to characterize these berries, with relation to chemical parameters, total phenols, total flavonoids, total vitamin C, and total anthocyanins, and was to investigate the solubility and the stability of anthocyanins from the berries. Moreover, the functional properties such as antioxidative activity, active oxygen species scavenging activity, and antihypertensive activity were also evaluated.Methods: Chemical analysis, colour measurement, and sensory evaluation of new everbearing strawberry cultivar, ‘Summertiara’ berries were performed. Next, the solubility of anthocyanins from the berries and stability of these against pH, temperature, and an incandescent lighting were investigated. Moreover, functional properties of the extracts prepared from berries were elucidated using 5 different methods.Results: The contents of water, proteins, lipids, carbohydrates, and ash were the same as those of other cultivar berries. The sugar-acid ratio in the berries was low; these were acidulous. By sensory evaluation, the main factors were vivid red colour, aroma, and acidity. The berries were rich in phenols, flavonoids, vitamin C, and anthocyanins. The anthocyanins of the berries became unstable by heat treatment and light exposures such as visible rays. On the other hand, the extracts prepared from the berries showed the functionalities such as antioxidant activity, active oxygen species scavenging activities, and antihypertensive activity.  Conclusions: The strawberry cultivar, ‘Summertiara’ berries were the most suitable for processing ingredient of strawberry-derived products with superior health promoting functionalities.Keywords: Summertiara, everbearing strawberry cultivar, characterization, sensory evaluation, color and storage, functional property

scholarly journals CLytA-DAAO Chimeric Enzyme Bound to Magnetic Nanoparticles. A New Therapeutical Approach for Cancer Patients?

2021 ◽  
Vol 22 (3) ◽  
pp. 1477
Author(s):  
María Fuentes-Baile ◽  
Elizabeth Pérez-Valenciano ◽  
Pilar García-Morales ◽  
Camino de Juan Romero ◽  
Daniel Bello-Gil ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Colorectal Carcinoma ◽  
Acid Oxidase ◽  
Oxygen Species ◽  
Cell Models ◽  
Amino Acid Oxidase ◽  
Direct Addition ◽  
Alginate Capsules ◽  
Anti Cancer ◽  
The Stability

D-amino acid oxidase (DAAO) is an enzyme that catalyzes the oxidation of D-amino acids generating H2O2. The enzymatic chimera formed by DAAO bound to the choline-binding domain of N-acetylmuramoyl-L-alanine amidase (CLytA) induces cytotoxicity in several pancreatic and colorectal carcinoma and glioblastoma cell models. In the current work, we determined whether the effect of CLytA-DAAO immobilized in magnetic nanoparticles, gold nanoparticles, and alginate capsules offered some advantages as compared to the free CLytA-DAAO. Results indicate that the immobilization of CLytA-DAAO in magnetic nanoparticles increases the stability of the enzyme, extending its time of action. Besides, we compared the effect induced by CLytA-DAAO with the direct addition of hydrogen peroxide, demonstrating that the progressive generation of reactive oxygen species by CLytA-DAAO is more effective in inducing cytotoxicity than the direct addition of H2O2. Furthermore, a pilot study has been initiated in biopsies obtained from pancreatic and colorectal carcinoma and glioblastoma patients to evaluate the expression of the main genes involved in resistance to CLytA-DAAO cytotoxicity. Based on our findings, we propose that CLytA-DAAO immobilized in magnetic nanoparticles could be effective in a high percentage of patients and, therefore, be used as an anti-cancer therapy for pancreatic and colorectal carcinoma and glioblastoma.

TiO2 suspension exposed to H2O2 in ambient light or darkness: Degradation of methylene blue and EPR evidence for radical oxygen species

2013 ◽  
Vol 142-143 ◽  
pp. 662-667 ◽  
Author(s):  
Luis Domínguez Sánchez ◽  
Sébastien Francis Michel Taxt-Lamolle ◽  
Eli Olaug Hole ◽  
André Krivokapić ◽  
Einar Sagstuen ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Oxygen Species ◽  
Ambient Light ◽  
Radical Oxygen Species

Rescue of anaemia and autoimmune responses in SOD1-deficient mice by transgenic expression of human SOD1 in erythrocytes

2009 ◽  
Vol 422 (2) ◽  
pp. 313-320 ◽  
Author(s):  
Yoshihito Iuchi ◽  
Futoshi Okada ◽  
Rina Takamiya ◽  
Noriko Kibe ◽  
Satoshi Tsunoda ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Energy Charge ◽  
Reactive Oxygen ◽  
Oxidative Modification ◽  
Autoimmune Response ◽  
Oxygen Species ◽  
Autoantibody Production ◽  
Deficient Mice ◽  
Human Sod1

Oxidative stress has been implicated as a cause of various diseases such as anaemia. We found that the SOD1 [Cu,Zn-SOD (superoxide dismutase)] gene deficiency causes anaemia, the production of autoantibodies against RBCs (red blood cells) and renal damage. In the present study, to further understand the role of oxidative stress in the autoimmune response triggered by SOD1 deficiency, we generated mice that had the hSOD1 (human SOD1) transgene under regulation of the GATA-1 promoter, and bred the transgene onto the SOD1−/− background (SOD1−/−;hSOD1tg/+). The lifespan of RBCs, levels of intracellular reactive oxygen species, and RBC content in SOD1−/−;hSOD1tg/+ mice, were approximately equivalent to those of SOD1+/+ mice. The production of antibodies against lipid peroxidation products, 4-hydroxy-2-nonenal and acrolein, as well as autoantibodies against RBCs and carbonic anhydrase II were elevated in the SOD1−/− mice, but were suppressed in the SOD1−/−;hSOD1tg/+ mice. Renal function, as judged by blood urea nitrogen, was improved in the transgenic mice. These results rule out the involvement of a defective immune system in the autoimmune response of SOD1-deficient mice, because SOD1−/−;hSOD1tg/+ mice carry the hSOD1 protein only in RBCs. Metabolomic analysis indicated a shift in glucose metabolism to the pentose phosphate pathway and a decrease in the energy charge potential of RBCs in SOD1-deficient mice. We conclude that the increase in reactive oxygen species due to SOD1 deficiency accelerates RBC destruction by affecting carbon metabolism and increasing oxidative modification of lipids and proteins. The resulting oxidation products are antigenic and, consequently, trigger autoantibody production, leading to autoimmune responses.

scholarly journals Revisiting the Oxidation of Flavonoids: Loss, Conservation or Enhancement of Their Antioxidant Properties

Antioxidants ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 133
Author(s):  
Hernan Speisky ◽  
Fereidoon Shahidi ◽  
Adriano Costa de Camargo ◽  
Jocelyn Fuentes
Keyword(s):  
Antioxidant Capacity ◽  
Antioxidant Properties ◽  
Oxidative Modification ◽  
Oxygen Species ◽  
Ros Scavenging ◽  
High Susceptibility ◽  
Comprehensive Description ◽  
Health Promoting ◽  
Endogenous Antioxidant ◽  
Electrophilic Character

Flavonoids display a broad range of health-promoting bioactivities. Among these, their capacity to act as antioxidants has remained most prominent. The canonical reactive oxygen species (ROS)-scavenging mode of the antioxidant action of flavonoids relies on the high susceptibility of their phenolic moieties to undergo oxidation. As a consequence, upon reaction with ROS, the antioxidant capacity of flavonoids is severely compromised. Other phenol-compromising reactions, such as those involved in the biotransformation of flavonoids, can also markedly affect their antioxidant properties. In recent years, however, increasing evidence has indicated that, at least for some flavonoids, the oxidation of such residues can in fact markedly enhance their original antioxidant properties. In such apparent paradoxical cases, the antioxidant activity arises from the pro-oxidant and/or electrophilic character of some of their oxidation-derived metabolites and is exerted by activating the Nrf2–Keap1 pathway, which upregulates the cell’s endogenous antioxidant capacity, and/or, by preventing the activation of the pro-oxidant and pro-inflammatory NF-κB pathway. This review focuses on the effects that the oxidative and/or non-oxidative modification of the phenolic groups of flavonoids may have on the ability of the resulting metabolites to promote direct and/or indirect antioxidant actions. Considering the case of a metabolite resulting from the oxidation of quercetin, we offer a comprehensive description of the evidence that increasingly supports the concept that, in the case of certain flavonoids, the oxidation of phenolics emerges as a mechanism that markedly amplifies their original antioxidant properties. An overlooked topic of great phytomedicine potential is thus unraveled.

scholarly journals Modifications of proteins of membrane-cytoskeleton complex and production of reactive oxygen species in erythrocytes cryopreserved with polyethylene glycol

2021 ◽  
Vol 67 (2) ◽  
pp. 44-52
Author(s):  
N.G. Zemlianskykh ◽  
◽  
L.O. Babiychuk ◽  
Keyword(s):  
Reactive Oxygen Species ◽  
Polyethylene Glycol ◽  
Protein Profile ◽  
Control Level ◽  
Reactive Oxygen ◽  
Fold Increase ◽  
Oxygen Species ◽  
Membrane Cytoskeleton ◽  
Extreme Factors ◽  
The Stability

Protein modifications in the membrane-cytoskeleton complex (MCC) of human erythrocytes, as well as changes in the intensity of reactive oxygen species (ROS) production upon cell cryopreservation with polyethylene glycol (PEG) were investigated. The protein profile of ghosts of erythrocytes frozen with PEG has common features with both the control and cells frozen without cryoprotectant. PEG makes it possible to restrict the structural rearrangements of the main MCC proteins under the effect of extreme factors and to restrain the amount of high molecular weight polypeptide complexes induced by the protein-cross-linking reagent diamide at the control level, in contrast to cells frozen without a cryoprotectant. However, changes related to the protein peroxiredoxin 2 in ghosts of erythrocytes cryopreserved with PEG are also attributed to cells frozen without a cryoprotectant that may be associated with the activation of oxidative processes. This is evidenced by a 10-fold increase in ROS formation in erythrocytes frozen under PEG protection. Thus, upon cryopreservation of erythrocytes with PEG, certain disorders in MCC proteins may be associated with increased formation of ROS, which may contribute to the disorganization of the structural components of MCC and disrupt the stability of cryopreserved cells under physiological conditions.

scholarly journals Thymol improves salinity tolerance of tobacco by increasing the Na+ efflux and enhancing the content of NO and GSH

2021 ◽  
Author(s):  
liang xu ◽  
Jia-Qian Song ◽  
yuelin wang ◽  
Xiao-Han Liu ◽  
Xue-Li Li ◽  
...  
Keyword(s):  
Salt Stress ◽  
Salt Tolerance ◽  
Root Growth ◽  
Abiotic Stresses ◽  
Nature Medicine ◽  
Oxygen Species ◽  
Plant Tolerance ◽  
Ros Accumulation ◽  
Na Efflux ◽  
The Stability

Abstract Plants have evolved a lot of strategies to improve salt tolerance to cope with salt stress. Recent studies have suggested that thymol (a nature medicine) enhances the plant tolerance against abiotic stresses, but the mechanisms are rarely known. Here, we found that thymol played an important role in maintaining root growth under salt stress. Thymol rescued root growth from salt stress via ameliorating ROS (reactive oxygen species) accumulation, lipid peroxidation, and cell death. In addition, thymol enhanced the level of NO (nitric oxide) and GSH (glutathione) to repress ROS accumulation, further protecting the stability of cell membrane. Thymol-induced Na+ efflux in roots and leaves under salt stress may depend on the upregulation of SOS1, HKT1 and NHX1. Consequently, all of these evidences suggested that thymol improved tobacco salt tolerance via enhancing NO and GSH content as well as inducing Na+ efflux.

Oxidation of Plasmalogens Produces Highly Effective Modulators of Macrophage Function

2000 ◽  
Vol 55 (1-2) ◽  
pp. 115-120 ◽  
Author(s):  
Helmut Heinle ◽  
Nadja Gugeler ◽  
Roswitha Felde ◽  
Dagmar Okech ◽  
Gerhard Spiteller
Keyword(s):  
Degradation Products ◽  
Oxidative Degradation ◽  
Oxidative Modification ◽  
Oxygen Species ◽  
Cytotoxic Effects ◽  
Macrophage Function ◽  
Enhanced Chemiluminescence ◽  
Derivatives Of ◽  
Assay Conditions

Abstract Model derivatives of plasmalogens and chemically synthesized oxidative degradation products as found e.g. during oxidation of low density lipoproteins show strong effects on phagocytosis induced secretion of reactive oxygen species of macrophages which was measured by luminol-enhanced chemiluminescence. Whereas a plasmalogen epoxide showed enhancing effects in submicromolar range, inhibition was found with higher concentrations as well as with a-hydroxyaldehydes. The substances showed only little effects on the non-cellular ROSdependent chemiluminescence of the reaction between hydrogen peroxide and opsonized zymosan and no cytotoxic effects under the assay conditions used. These results show that oxidative modification and degradation of plasmalogens occuring also under pathophysiological situations in vivo produces effective modulators of macrophage function which could be important; e.g. during inflammation or atherogenesis.

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