Nejvíce citovaný článek - PubMed ID 31284470
Mechanism of the Formation of Electronically Excited Species by Oxidative Metabolic Processes: Role of Reactive Oxygen Species
The oxidative damage induced by abiotic stress factors such as salinity, drought, extreme temperatures, heavy metals, pollution, and high irradiance has been studied in Arabidopsis thaliana. Ultra-weak photon emission (UPE) is presented as a signature reflecting the extent of the oxidation process and/or damage. It can be used to predict the physiological state and general health of plants. This study presents an overview of a potential research platform where the technique can be applied. The results presented can aid in providing invaluable information for developing strategies to mitigate abiotic stress in crops by improving plant breeding programs with a focus on enhancing tolerance. This study evaluates the applicability of charged couple device (CCD) imaging in evaluating plant stress and degree of damage and to discuss the advantages and limitations of the claimed non-invasive label-free tool.
- Klíčová slova
- Antioxidants, Reactive oxygen species, Stress imaging, Two-dimensional photon emission imaging, Wounding,
- MeSH
- Arabidopsis * fyziologie MeSH
- fotony * MeSH
- fyziologický stres * MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Technologies based on pulsed electric field (PEF) are increasingly pervasive in medical and industrial applications. However, the detailed understanding of how PEF acts on biosamples including proteins at the molecular level is missing. There are indications that PEF might act on biomolecules via electrogenerated reactive oxygen species (ROS). However, it is unclear how this action is modulated by the pro- and antioxidants, which are naturally present components of biosamples. This knowledge gap is often due to insufficient sensitivity of the conventionally utilized detection assays. To overcome this limitation, here we employed an endogenous (bio)chemiluminescence sensing platform, which enables sensitive detection of PEF-generated ROS and oxidative processes in proteins, to inspect effects of pro-and antioxidants. Taking bovine serum albumin (BSA) as a model protein, we found that the chemiluminescence signal arising from its solution is greatly enhanced in the presence of H 2 O 2 as a prooxidant, especially during PEF treatment. In contrast, the chemiluminescence signal decreases in the presence of antioxidant enzymes (catalase, superoxide dismutase), indicating the involvement of both H 2 O 2 and electrogenerated superoxide anion in oxidation-reporting chemiluminescence signal before, during, and after PEF treatment. We also performed additional biochemical and biophysical assays, which confirmed that BSA underwent structural changes after H 2 O 2 treatment, with PEF having only a minor effect. We proposed a scheme describing the reactions leading from interfacial charge transfer at the anode by which ROS are generated to the actual photon emission. Results of our work help to elucidate the mechanisms of action of PEF on proteins via electrogenerated reactive oxygen species and open up new avenues for the application of PEF technology. The developed chemiluminescence technique enables label-free, in-situ and non-destructive sensing of interactions between ROS and proteins. The technique may be applied to study oxidative damage of other classes of biomolecules such as lipids, nucleic acids or carbohydrates.
- MeSH
- antioxidancia * metabolismus MeSH
- elektřina MeSH
- katalasa metabolismus MeSH
- luminiscence MeSH
- luminiscenční měření * metody MeSH
- oxidace-redukce * MeSH
- peroxid vodíku metabolismus MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- sérový albumin hovězí * metabolismus MeSH
- skot MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antioxidancia * MeSH
- katalasa MeSH
- peroxid vodíku MeSH
- reaktivní formy kyslíku * MeSH
- sérový albumin hovězí * MeSH
Anthropogenic activities and subsequent global climate change instigate drastic crop productivity and yield changes. These changes comprise a rise in the number and severity of plant stress factors, which can arise simultaneously or sequentially. When abiotic stress factors are combined, their impact on plants is more substantial than that of a singleton stress factor. One such impact is the alteration of redox cellular homeostasis, which, in turn, can regulate downstream stress-responsive gene expression and resistance response. The epigenetic regulation of gene expression in response to varied stress factors is an interesting phenomenon, which, conversely, can be stable and heritable. The epigenetic control in plants in response to abiotic stress combinations and their interactions with cellular redox alteration is an emerging field to commemorate crop yield management under climate change. The article highlights the integration of the redox signaling pathways and epigenetic regulations as pivotal components in the complex network of plant responses against multi-combinatorial stresses across time and space. This review aims to lay the foundation for developing novel approaches to mitigate the impact of environmental stresses on crop productivity, bridging the gap between theoretical understanding and practical solutions in the face of a changing climate and anthropogenic disturbances.
- Klíčová slova
- abiotic stress, anthropogenic disturbances, crop resilience, epigenetic regulation, histone modification, reactive oxygen species,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Extracellular vesicles (EVs) are a type of cytoplasmic vesicles secreted by a variety of cells. EVs originating from cells have been known to participate in cell communication, antigen presentation, immune cell activation, tolerance induction, etc. These EVs can also carry the active form of Nicotinamide Adenine Dinucleotide Phosphate Oxidase Hydrogen (NADPH) oxidase, which is very essential for the production of reactive oxygen species (ROS) and that can then modulate processes such as cell regeneration. The aim of this study is to characterize the EVs isolated from U-937 and THP-1 cells, identify the NADPH oxidase (NOX) isoforms, and to determine whether EVs can modulate NOX4 and NOX2 in monocytes and macrophages. In our study, isolated EVs of U-937 were characterized using dynamic light scattering (DLS) spectroscopy and immunoblotting. The results showed that the exogenous addition of differentiation agents (either phorbol 12-myristate 13-acetate (PMA) or ascorbic acid) or the supplementation of EVs used in the study did not cause any stress leading to alterations in cell proliferation and viability. In cells co-cultured with EVs for 72 h, strong suppression of NOX4 and NOX2 is evident when monocytes transform into macrophagic cells. We also observed lower levels of oxidative stress measured using immunoblotting and electron paramagnetic resonance spectroscopy under the EVs co-cultured condition, which also indicates that EVs might contribute significantly by acting as an antioxidant source, which agrees with previous studies that hypothesized the role of EVs in therapeutics. Therefore, our results provide evidence for NOX regulation by EVs in addition to its role as an antioxidant cargo.
- Klíčová slova
- NADPH oxidase, NOX2, NOX4, extracellular vesicles, free radicals, macrophages, monocytes, reactive oxygen species,
- Publikační typ
- časopisecké články MeSH
In this study, we investigated the properties of ascorbic acid (vitamin C), which is a naturally occurring water-soluble vitamin. Our goal is to evaluate its pro-oxidative and/or antioxidant capabilities. To do this, we initially used a confocal laser scanning microscope (CLSM) to visualize the differentiation pattern in U-937 cells under the treatment of variable concentrations of ascorbic acid. Prior to induction, U-937 cells showed a spherical morphology. After treatment, significant morphological changes were observed in the form of prominent pseudopodia and amoeboid structures. Interestingly, pseudopodia incidences increased with an increase in ascorbic acid concentrations. In addition, our analysis of protein modification using anti-malondialdehyde antibodies showed changes in more than one protein. The findings reveal the link between the differentiation of U-937 cells into macrophages and the protein modifications triggered by the production of reactive oxygen species when U-937 cells are exposed to ascorbic acid. Furthermore, the transformation of ascorbic acid from a pro-oxidative to an antioxidant property is also demonstrated.
- Klíčová slova
- Antioxidants, Human cells, Pro-oxidant, Reactive oxygen species, Vitamin C,
- Publikační typ
- časopisecké články MeSH
Skin plays an important role in protection, metabolism, thermoregulation, sensation, and excretion whilst being consistently exposed to environmental aggression, including biotic and abiotic stresses. During the generation of oxidative stress in the skin, the epidermal and dermal cells are generally regarded as the most affected regions. The participation of reactive oxygen species (ROS) as a result of environmental fluctuations has been experimentally proven by several researchers and is well known to contribute to ultra-weak photon emission via the oxidation of biomolecules (lipids, proteins, and nucleic acids). More recently, ultra-weak photon emission detection techniques have been introduced to investigate the conditions of oxidative stress in various living systems in in vivo, ex vivo and in vitro studies. Research into two-dimensional photon imaging is drawing growing attention because of its application as a non-invasive tool. We monitored spontaneous and stress-induced ultra-weak photon emission under the exogenous application of a Fenton reagent. The results showed a marked difference in the ultra-weak photon emission. Overall, these results suggest that triplet carbonyl (3C=O∗) and singlet oxygen (1O2) are the final emitters. Furthermore, the formation of oxidatively modified protein adducts and protein carbonyl formation upon treatment with hydrogen peroxide (H2O2) were observed using an immunoblotting assay. The results from this study broaden our understanding of the mechanism of the generation of ROS in skin layers and the formation/contribution of various excited species can be used as tools to determine the physiological state of the organism.
- Klíčová slova
- malondialdehyde, oxidative radical reaction, porcine skin, protein carbonyls, protein modification, reactive oxygen species, two-dimensional imaging, ultra-weak photon emission,
- MeSH
- kůže * metabolismus MeSH
- oxidace-redukce MeSH
- oxidační stres MeSH
- peroxid vodíku * metabolismus MeSH
- proteiny metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- peroxid vodíku * MeSH
- proteiny MeSH
- reaktivní formy kyslíku MeSH
Reactive oxygen species (ROS) represent a group of molecules with a signaling role that are involved in regulating human cell proliferation and differentiation. Increased ROS concentrations are often associated with the local nonspecific oxidation of biological macromolecules, especially proteins and lipids. Free radicals, in general, may randomly damage protein molecules through the formation of protein-centered radicals as intermediates that, in turn, decay into several end oxidation products. Malondialdehyde (MDA), a marker of free-radical-mediated lipid oxidation and cell membrane damage, forms adducts with proteins in a nonspecific manner, leading to the loss of their function. In our study, we utilized U-937 cells as a model system to unveil the effect of four selected bioactive compounds (chlorogenic acid, oleuropein, tomatine, and tyrosol) to reduce oxidative stress associated with adduct formation in differentiating cells. The purity of the compounds under study was confirmed by an HPLC analysis. The cellular integrity and changes in the morphology of differentiated U-937 cells were confirmed with confocal microscopy, and no significant toxicity was found in the presence of bioactive compounds. From the Western blot analysis, a reduction in the MDA adduct formation was observed in cells treated with compounds that underlaid the beneficial effects of the compounds tested.
- Klíčová slova
- antioxidants, bioactive compounds, macrophage, malondialdehyde, monocyte, nutraceuticals, phorbol 12-myristate 13-acetate, protein modification, reactive oxygen species, redox reactions,
- MeSH
- lidé MeSH
- malondialdehyd MeSH
- oxidace-redukce MeSH
- oxidační stres * MeSH
- reaktivní formy kyslíku farmakologie MeSH
- volné radikály metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- malondialdehyd MeSH
- reaktivní formy kyslíku MeSH
- volné radikály MeSH
Reactive oxygen species (ROS) are formed in photosystem II (PSII) under various types of abiotic and biotic stresses. It is considered that ROS play a role in chloroplast-to-nucleus retrograde signaling, which changes the nuclear gene expression. However, as ROS lifetime and diffusion are restricted due to the high reactivity towards biomolecules (lipids, pigments, and proteins) and the spatial specificity of signal transduction is low, it is not entirely clear how ROS might transduce signal from the chloroplasts to the nucleus. Biomolecule oxidation was formerly connected solely with damage; nevertheless, the evidence appears that oxidatively modified lipids and pigments are be involved in chloroplast-to-nucleus retrograde signaling due to their long diffusion distance. Moreover, oxidatively modified proteins show high spatial specificity; however, their role in signal transduction from chloroplasts to the nucleus has not been proven yet. The review attempts to summarize and evaluate the evidence for the involvement of ROS in oxidative signaling in PSII.
- Klíčová slova
- Chloroplast-to-nucleus retrograde signaling, Lipid peroxidation, Protein oxidation, Reactive oxygen species,
- MeSH
- chloroplasty * metabolismus MeSH
- fotosystém II (proteinový komplex) * metabolismus MeSH
- lipidy MeSH
- oxidační stres MeSH
- reaktivní formy kyslíku metabolismus MeSH
- signální transdukce fyziologie MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- fotosystém II (proteinový komplex) * MeSH
- lipidy MeSH
- reaktivní formy kyslíku MeSH
Free radical-mediated activation of inflammatory macrophages remains ambiguous with its limitation to study within biological systems. U-937 and HL-60 cell lines serve as a well-defined model system known to differentiate into either macrophages or dendritic cells in response to various chemical stimuli linked with reactive oxygen species (ROS) production. Our present work utilizes phorbol 12-myristate-13-acetate (PMA) as a stimulant, and factors such as concentration and incubation time were considered to achieve optimized differentiation conditions. ROS formation likely hydroxyl radical (HO●) was confirmed by electron paramagnetic resonance (EPR) spectroscopy combined with confocal laser scanning microscopy (CLSM). In particular, U-937 cells were utilized further to identify proteins undergoing oxidation by ROS using anti-DMPO (5,5-dimethyl-1-pyrroline N-oxide) antibodies. Additionally, the expression pattern of NADPH Oxidase 4 (NOX4) in relation to induction with PMA was monitored to correlate the pattern of ROS generated. Utilizing macrophages as a model system, findings from the present study provide a valuable source for expanding the knowledge of differentiation and protein expression dynamics.
- Klíčová slova
- HL-60 cells, NADPH oxidase, NOX4, U-937 cells, macrophages, phorbol 12-myristate 13-acetate, protein-centered radicals,
- MeSH
- acetofenony farmakologie MeSH
- barvení a značení MeSH
- buněčná diferenciace * účinky léků MeSH
- elektronová paramagnetická rezonance MeSH
- HL-60 buňky MeSH
- hydroxylový radikál MeSH
- lidé MeSH
- monocyty cytologie účinky léků metabolismus MeSH
- NADP metabolismus MeSH
- proliferace buněk účinky léků MeSH
- proteiny metabolismus MeSH
- tetradekanoylforbolacetát farmakologie MeSH
- tvar buňky účinky léků MeSH
- U937 buňky MeSH
- viabilita buněk účinky léků MeSH
- volné radikály metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acetofenony MeSH
- acetovanillone MeSH Prohlížeč
- hydroxylový radikál MeSH
- NADP MeSH
- proteiny MeSH
- tetradekanoylforbolacetát MeSH
- volné radikály MeSH
Nowadays, modern medicine is looking for new, more gentle, and more efficient diagnostic methods. A pathological state of an organism is often closely connected with increased amount of reactive oxygen species. They can react with biomolecules and subsequent reactions can lead to very low endogenous light emission (biological autoluminescence-BAL). This phenomenon can be potentially used as a non-invasive and low-operational-cost tool for monitoring oxidative stress during diseases. To contribute to the understanding of the parameters affecting BAL, we analyzed the BAL from yeast Saccharomyces cerevisiae as a representative eukaryotic organism. The relationship between the BAL intensity and the amount of reactive oxygen species that originates as a result of the Fenton reaction as well as correlation between spontaneous BAL and selected physical and chemical parameters (pH, oxygen partial pressure, and cell concentration) during cell growth were established. Our results contribute to real-time non-invasive methodologies for monitoring oxidative processes in biomedicine and biotechnology.
