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Biochimica Et Biophysica Acta.... Jun 2024This review explores the nuanced role of reactive oxygen species (ROS) in cell fate, challenging the traditional view that equates ROS with cellular damage. Through... (Review)
Review
This review explores the nuanced role of reactive oxygen species (ROS) in cell fate, challenging the traditional view that equates ROS with cellular damage. Through significant technological advancements in detecting localized redox states and identifying oxidized cysteines, a paradigm shift has emerged: from ROS as merely damaging agents to crucial players in redox signaling. We delve into the intricacies of redox mechanisms, which, although confined, exert profound influences on cellular physiological responses. Our analysis extends to both the positive and negative impacts of these mechanisms on cell death processes, including uncontrolled and programmed pathways. By unraveling these complex interactions, we argue against the oversimplified notion of a 'stress response', advocating for a more nuanced understanding of redox signaling. This review underscores the importance of localized redox states in determining cell fate, highlighting the sophistication and subtlety of ROS functions beyond mere damage.
Topics: Reactive Oxygen Species; Oxidation-Reduction; Humans; Signal Transduction; Oxidative Stress; Animals; Apoptosis
PubMed: 38615720
DOI: 10.1016/j.bbamcr.2024.119722 -
Frontiers in Immunology 2023Novel biomarkers of inflammation and oxidative stress might enhance the early recognition, management, and clinical outcomes of patients with rheumatic diseases (RDs).... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Novel biomarkers of inflammation and oxidative stress might enhance the early recognition, management, and clinical outcomes of patients with rheumatic diseases (RDs). We assessed the available evidence regarding the pathophysiological role of neopterin, the oxidation product of 7,8-dihydroneopterin, a pteridine generated in macrophages activated by interferon-γ, by conducting a systematic review and meta-analysis of studies reporting its concentrations in biological fluids in RD patients and healthy controls.
METHODS
We searched electronic databases for relevant articles published between inception and 31 August 2023. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and the Grades of Recommendation, Assessment, Development and Evaluation Working Group system, respectively.
RESULTS
In 37 studies, when compared to healthy controls, RD patients had significantly higher concentrations of neopterin both in plasma or serum (standard mean difference, SMD=1.31, 95% CI 1.01 to 1.61; p<0.001; moderate certainty of evidence) and in the urine (SMD=1.65, 95% CI 0.86 to 2.43, p<0.001; I = 94.2%, p<0.001; low certainty of evidence). The results were stable in sensitivity analysis. There were non-significant associations in meta-regression and subgroup analysis between the effect size and age, male to female ratio, year of publication, sample size, RD duration, C-reactive protein, erythrocyte sedimentation rate, specific type of RD, presence of connective tissue disease, analytical method used, or biological matrix investigated (plasma . serum). By contrast, the effect size was significantly associated with the geographical area in studies assessing serum or plasma and with the type of RD in studies assessing urine.
DISCUSSION
Pending additional studies that also focus on early forms of disease, our systematic review and meta-analysis supports the proposition that neopterin, a biomarker of inflammation and oxidative stress, can be useful for the identification of RDs. (PROSPERO registration number: CRD42023450209).
SYSTEMATIC REVIEW REGISTRATION
PROSPERO, identifier CRD42023450209.
Topics: Humans; Male; Female; Neopterin; Inflammation; Oxidation-Reduction; Oxidative Stress; Rheumatic Diseases; Biomarkers
PubMed: 37799718
DOI: 10.3389/fimmu.2023.1271383 -
Environmental Science & Technology Nov 2023Water quality and its impacts on human and ecosystem health presents tremendous global challenges. While oxidative water treatment can solve many of these problems... (Review)
Review
Water quality and its impacts on human and ecosystem health presents tremendous global challenges. While oxidative water treatment can solve many of these problems related to hygiene and micropollutants, identifying and predicting transformation products from a large variety of micropollutants induced by dosed chemical oxidants and in situ formed radicals is still a major challenge. To this end, a better understanding of the formed transformation products and their potential toxicity is needed. Currently, no theoretical tools alone can predict oxidatively induced transformation products in aqueous systems. Coupling experimental and theoretical studies has advanced the understanding of reaction kinetics and mechanisms significantly. This perspective article highlights the key progress made concerning experimental and computational approaches to predict transformation products. Knowledge gaps are identified, and the research required to advance the predictive capability is discussed.
Topics: Humans; Ecosystem; Water Pollutants, Chemical; Oxidation-Reduction; Oxidants; Models, Theoretical; Kinetics
PubMed: 37824098
DOI: 10.1021/acs.est.3c04086 -
Scientific Reports Sep 2023Maintaining life (respiration), cell death (apoptosis), oxygen transport and immunity are main biological functions of heme containing proteins. These functions are...
Maintaining life (respiration), cell death (apoptosis), oxygen transport and immunity are main biological functions of heme containing proteins. These functions are controlled by the axial ligands and the redox status of the iron ion (oscillations between Fe and Fe) in the heme group. This paper aims to evaluate the current state of knowledge on oxidation and oxygenation effects in heme proteins. We determined the redox status of the iron ion in whole blood (without and with anticoagulant), hemoglobin in erythrocytes, in isolated cytochrome c and cytochrome c in mitochondria of the human lung cancer cells using UV-VIS electronic absorption spectroscopy, Raman spectroscopy and Raman imaging. Here we discussed the mechanism responsible for the Q electronic absorption band spectral behavior, i.e., its splitting, and its change in extinction coefficient, as well as vibrational modifications upon oxygenation and oxidation. We compared the redox status of heme in hemoglobin of human erythrocytes and cytochrome c in mitochondria of human lung cancer cells. Presented results allow simultaneous identification of oxy- and deoxy-Hb, where 1547 and 1604 cm vibrations correspond to deoxygenated hemoglobin, while 1585 and 1638 cm correspond to oxyhemoglobin, respectively. Our results extend knowledge of oxidation and oxygenation effects in heme proteins. We demonstrated experimentally the mechanism of electronic-vibrational coupling for the Q band splitting. Presented results extend knowledge on oxidation and oxygenation effects in heme proteins and provide evidence that both processes are strongly coupled. We showed that retinoic acid affects the redox state of heme in cytochrome c in mitochondria. The change of the redox status of cytochrome c in mitochondria from the oxidized form to the reduced form has very serious consequences in dysfunction of mitochondria resulting in inhibition of respiration, apoptosis and cytokine induction.
Topics: Humans; Cytochromes c; Hemoglobins; Erythrocytes; Lung Neoplasms; Oxidation-Reduction; Hemeproteins; Heme; Lung
PubMed: 37679473
DOI: 10.1038/s41598-023-41858-z -
Environmental Science & Technology Aug 2023Bioelectrochemical systems (BESs) are considered to be energy-efficient to convert ammonium, which is present in wastewater. The application of BESs as a technology to...
Bioelectrochemical systems (BESs) are considered to be energy-efficient to convert ammonium, which is present in wastewater. The application of BESs as a technology to treat wastewater on an industrial scale is hindered by the slow removal rate and lack of understanding of the underlying ammonium conversion pathways. This study shows ammonium oxidation rates up to 228 ± 0.4 g-N m d under microoxic conditions (dissolved oxygen at 0.02-0.2 mg-O/L), which is a significant improvement compared to anoxic conditions (120 ± 21 g-N m d). We found that this enhancement was related to the formation of hydroxylamine (NHOH), which is rate limiting in ammonium oxidation by ammonia-oxidizing microorganisms. NHOH was intermediate in both the absence and presence of oxygen. The dominant end-product of ammonium oxidation was dinitrogen gas, with about 75% conversion efficiency in the presence of a microoxic level of dissolved oxygen and 100% conversion efficiency in the absence of oxygen. This work elucidates the dominant pathways under microoxic and anoxic conditions which is a step toward the application of BESs for ammonium removal in wastewater treatment.
Topics: Ammonium Compounds; Wastewater; Bioreactors; Oxidation-Reduction; Oxygen; Nitrogen
PubMed: 37498945
DOI: 10.1021/acs.est.3c02227 -
Biochemistry. Biokhimiia Oct 2023An overview of current notions on the mechanism of generation of a transmembrane electric potential difference (Δψ) during the catalytic cycle of a bd-type triheme... (Review)
Review
An overview of current notions on the mechanism of generation of a transmembrane electric potential difference (Δψ) during the catalytic cycle of a bd-type triheme terminal quinol oxidase is presented in this work. It is suggested that the main contribution to Δψ formation is made by the movement of H+ across the membrane along the intra-protein hydrophilic proton-conducting pathway from the cytoplasm to the active site for oxygen reduction of this bacterial enzyme.
Topics: Membrane Potentials; Cytochrome b Group; Escherichia coli Proteins; Electron Transport Chain Complex Proteins; Cytochromes; Oxidation-Reduction
PubMed: 38105020
DOI: 10.1134/S0006297923100073 -
International Journal of Molecular... Nov 2023Oxidative stress is frequently described as the balance between the production of reactive species (including oxygen and nitrogen) in biological systems and the ability...
Oxidative stress is frequently described as the balance between the production of reactive species (including oxygen and nitrogen) in biological systems and the ability of the latter to defend itself through the sophisticated antioxidant machinery [...].
Topics: Reactive Oxygen Species; Oxidative Stress; Oxidation-Reduction; Antioxidants
PubMed: 37959000
DOI: 10.3390/ijms242116018 -
Molecules (Basel, Switzerland) Dec 2023Nitrogenases have the remarkable ability to catalyze the reduction of dinitrogen to ammonia under physiological conditions. How does this happen? The current view of the... (Review)
Review
Nitrogenases have the remarkable ability to catalyze the reduction of dinitrogen to ammonia under physiological conditions. How does this happen? The current view of the nitrogenase mechanism focuses on the role of hydrides, the binding of dinitrogen in a reductive elimination process coupled to loss of dihydrogen, and the binding of substrates to a binuclear site on the active site cofactor. This review focuses on recent experimental characterizations of turnover relevant forms of the enzyme determined by cryo-electron microscopy and other approaches, and comparison of these forms to the resting state enzyme and the broader family of iron sulfur clusters. Emerging themes include the following: (i) The obligatory coupling of protein and electron transfers does not occur in synthetic and small-molecule iron-sulfur clusters. The coupling of these processes in nitrogenase suggests that they may involve unique features of the cofactor, such as hydride formation on the trigonal prismatic arrangement of irons, protonation of belt sulfurs, and/or protonation of the interstitial carbon. (ii) Both the active site cofactor and protein are dynamic under turnover conditions; the changes are such that more highly reduced forms may differ in key ways from the resting-state structure. Homocitrate appears to play a key role in coupling cofactor and protein dynamics. (iii) Structural asymmetries are observed in nitrogenase under turnover-relevant conditions by cryo-electron microscopy, although the mechanistic relevance of these states (such as half-of-sites reactivity) remains to be established.
Topics: Nitrogenase; Cryoelectron Microscopy; Hydrogen; Iron; Sulfur; Oxidation-Reduction
PubMed: 38138444
DOI: 10.3390/molecules28247952 -
Current Opinion in Chemical Biology Dec 2023Due to its nucleophilicity, the thiol group of cysteine is chemically very versatile. Hence, cysteine often has important functions in a protein, be it as the active... (Review)
Review
Due to its nucleophilicity, the thiol group of cysteine is chemically very versatile. Hence, cysteine often has important functions in a protein, be it as the active site or, in extracellular proteins, as part of a structural disulfide. Within the cytosol, cysteines are typically reduced. But the nucleophilicity of its thiol group makes it also particularly prone to post-translational oxidative modifications. These modifications often lead to an alteration of the function of the affected protein and are reversible in vivo, e.g. by the thioredoxin and glutaredoxin system. The in vivo-reversible nature of these modifications and their genesis in the presence of localized high oxidant levels led to the paradigm of thiol-based redox regulation, the adaptation, and modulation of the cellular metabolism in response to oxidative stimuli by thiol oxidation in regulative proteins. Consequently, the proteomic study of these oxidative posttranslational modifications of cysteine plays an indispensable role in redox biology.
Topics: Sulfhydryl Compounds; Cysteine; Proteomics; Oxidation-Reduction; Protein Processing, Post-Translational
PubMed: 37797572
DOI: 10.1016/j.cbpa.2023.102390 -
Antioxidative Effect of Dihydrosphingosine (d18:0) and α-Tocopherol on Tridocosahexaenoin (DHA-TAG).Journal of Agricultural and Food... Oct 2023Sphingoid bases have shown promise as effective antioxidants in fish oils together with α-tocopherol, and the effect has been attributed to products resulting from...
Sphingoid bases have shown promise as effective antioxidants in fish oils together with α-tocopherol, and the effect has been attributed to products resulting from amino-carbonyl reactions (lipation products) between the sphingoid base amine group and carbonyl compounds from lipid oxidation. In this study, the synergistic effect of dihydrosphingosine (d18:0) and α-tocopherol was studied on pure docosahexaenoic acid (DHA) triacylglycerols with an omics-type liquid- and gas-chromatographic mass spectrometric approach to verify the synergistic effect, to get a comprehensive view on the effect of d18:0 on the oxidation pattern, and to identify the lipation products. The results confirmed that d18:0 rapidly reacts further in the presence of lipid oxidation products and α-tocopherol. α-Tocopherol and d18:0 showed an improved antioxidative effect after 12 h of oxidation, indicating the formation of antioxidants through carbonyl-amine reactions. Imines formed from the carbonyls and d18:0 could be tentatively identified.
Topics: Antioxidants; alpha-Tocopherol; Docosahexaenoic Acids; Sphingosine; Oxidation-Reduction
PubMed: 37751317
DOI: 10.1021/acs.jafc.3c02668