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Pediatric Research Oct 2023The study's objective is to evaluate if Molsidomine (MOL), an anti-oxidant, anti-inflammatory, and anti-apoptotic drug, is effective in treating hyperoxic lung injury...
BACKGROUND
The study's objective is to evaluate if Molsidomine (MOL), an anti-oxidant, anti-inflammatory, and anti-apoptotic drug, is effective in treating hyperoxic lung injury (HLI).
METHODS
The study consisted of four groups of neonatal rats characterized as the Control, Control+MOL, HLI, HLI + MOL groups. Near the end of the study, the lung tissue of the rats were evaluated with respect to apoptosis, histopathological damage, anti-oxidant and oxidant capacity as well as degree of inflammation.
RESULTS
Compared to the HLI group, malondialdehyde and total oxidant status levels in lung tissue were notably reduced in the HLI + MOL group. Furthermore, mean superoxide dismutase, glutathione peroxidase, and glutathione activities/levels in lung tissue were significantly higher in the HLI + MOL group as compared to the HLI group. Tumor necrosis factor-α and interleukin-1β elevations associated with hyperoxia were significantly reduced following MOL treatment. Median histopathological damage and mean alveolar macrophage numbers were found to be higher in the HLI and HLI + MOL groups when compared to the Control and Control+MOL groups. Both values were increased in the HLI group when compared to the HLI + MOL group.
CONCLUSIONS
Our research is the first to demonstrate that bronchopulmonary dysplasia may be prevented through the protective characteristics of MOL, an anti-inflammatory, anti-oxidant, and anti-apoptotic drug.
IMPACT
Molsidomine prophylaxis significantly decreased the level of oxidative stress markers. Molsidomine administration restored the activities of antioxidant enzymes. Molsidomine prophylaxis significantly reduced the levels of inflammatory cytokines. Molsidomine may provide a new and promising therapy for BPD in the future. Molsidomine prophylaxis decreased lung damage and macrophage infiltration in the tissue.
Topics: Rats; Animals; Lung Injury; Antioxidants; Molsidomine; Animals, Newborn; Rats, Wistar; Hyperoxia; Lung; Oxidative Stress; Oxidants; Anti-Inflammatory Agents
PubMed: 37179436
DOI: 10.1038/s41390-023-02643-w -
Advanced Materials (Deerfield Beach,... Feb 2024Excessive accumulation of reactive oxygen species (ROS) can lead to oxidative stress and oxidative damage, which is one of the important factors for aging and...
Excessive accumulation of reactive oxygen species (ROS) can lead to oxidative stress and oxidative damage, which is one of the important factors for aging and age-related diseases. Therefore, real-time monitoring and the moderate elimination of ROS is extremely important. In this study, a ROS-responsive circular dichroic (CD) at 553 nm and magnetic resonance imaging (MRI) dual-signals chiral manganese oxide (MnO ) nanoparticles (NPs) are designed and synthesized. Both the CD and MRI signals show excellent linear ranges for intracellular hydrogen peroxide (H O ) concentrations, with limits of detection (LOD) of 0.0027 nmol/10 cells and 0.016 nmol/10 cells, respectively. The lower LOD achieved with CD detection may be attributable to its higher anti-interference capability from the intracellular matrix. Importantly, ROS-induced cell aging is intervened by chiral MnO NPs via redox reactions with excessive intracellular ROS. In vivo experiments confirm that chiral MnO NPs effectively eliminate ROS in skin tissue, reduce oxidative stress levels, and alleviate skin aging. This approach provides a new strategy for the diagnosis and treatment of age-related diseases.
Topics: Reactive Oxygen Species; Oxides; Manganese Compounds; Nanoparticles; Hydrogen Peroxide
PubMed: 37766572
DOI: 10.1002/adma.202308469 -
Accounts of Chemical Research Nov 2023Aerobic organisms involve dioxygen-activating iron enzymes to perform various metabolically relevant chemical transformations. Among these enzymes, mononuclear non-heme...
Aerobic organisms involve dioxygen-activating iron enzymes to perform various metabolically relevant chemical transformations. Among these enzymes, mononuclear non-heme iron enzymes reductively activate dioxygen to catalyze diverse biological oxidations, including oxygenation of C-H and C═C bonds and C-C bond cleavage with amazing selectivity. Several non-heme enzymes utilize organic cofactors as electron sources for dioxygen reduction, leading to the generation of iron-oxygen intermediates that act as active oxidants in the catalytic cycle. These unique enzymatic reactions influence the design of small molecule synthetic compounds to emulate enzyme functions and to develop bioinspired catalysts for performing selective oxidation of organic substrates with dioxygen. Selective electron transfer during dioxygen reduction on iron centers of synthetic models by a sacrificial reductant requires appropriate design strategies. Taking lessons from the role of enzyme-cofactor complexes in the selective electron transfer process, our group utilized ternary iron(II)-α-hydroxy acid complexes supported by polydentate ligands for dioxygen reduction and bioinspired oxidations. This Account focuses on the role of coordinated sacrificial reductants in the selective electron transfer for dioxygen reduction by iron complexes and highlights the versatility of iron(II)-α-hydroxy acid complexes in affecting dioxygen-dependent oxidation/oxygenation reactions. The iron(II)-coordinated α-hydroxy acid anions undergo two-electron oxidative decarboxylation concomitant with the generation of reactive iron-oxygen oxidants. A nucleophilic iron(II)-hydroperoxo species was intercepted in the decarboxylation pathway. In the presence of a Lewis acid, the O-O bond of the nucleophilic oxidant is heterolytically cleaved to generate an electrophilic iron(IV)-oxo-hydroxo oxidant. Most importantly, the oxidants generated with or without Lewis acid can carry out -dihydroxylation of alkenes. Furthermore, the electrophilic iron-oxygen oxidant selectively hydroxylates strong C-H bonds. Another electrophilic iron(IV)-oxo oxidant, generated from the iron(II)-α-hydroxy acid complexes in the presence of a protic acid, carries out C-H bond halogenation by using a halide anion.Thus, different metal-oxygen intermediates could be generated from dioxygen using a single reductant, and the reactivity of the ternary complexes can be tuned using external additives (Lewis/protic acid). The catalytic potential of the iron(II)-α-hydroxy complexes in performing O-dependent oxygenations has been demonstrated. Different factors that govern the reactivity of iron-oxygen oxidants from ternary iron(II) complexes are presented. The versatile reactivity of the oxidants provides useful insights into developing catalytic methods for the selective incorporation of oxidized functionalities under environmentally benign conditions using aerial oxygen as the terminal oxidant.
Topics: Lewis Acids; Oxygen; Reducing Agents; Iron; Oxidation-Reduction; Oxidants; Ferrous Compounds; Hydroxy Acids
PubMed: 37938969
DOI: 10.1021/acs.accounts.3c00449 -
Water Research Oct 2023Microbial degradation to remove residual antibiotics in wastewater is of growing interest. However, biological treatment of antibiotics may cause resistance...
Microbial degradation to remove residual antibiotics in wastewater is of growing interest. However, biological treatment of antibiotics may cause resistance dissemination by mutations and horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). In this study, a Mn(Ⅱ)-oxidizing bacterium (MnOB), Pseudomonas aeruginosa MQ2, simultaneously degraded antibiotics, decreased HGT, and mitigated antibiotic resistance mutation. Intracellular Mn(II) levels increased during manganese oxidation, and biogenic manganese oxides (BioMnOx, including Mn(II), Mn(III) and Mn(IV)) tightly coated the cell surface. Mn(II) bio-oxidation mitigated antibiotic resistance acquisition from an E. coli ARG donor and mitigated antibiotic resistance inducement by decreasing conjugative transfer and mutation, respectively. BioMnOx also oxidized ciprofloxacin (1 mg/L) and tetracycline (5 mg/L), respectively removing 93% and 96% within 24 h. Transcriptomic analysis revealed that two new multicopper oxidase and one peroxidase genes are involved in Mn(II) oxidation. Downregulation of SOS response, multidrug resistance and type Ⅳ secretion system related genes explained that Mn(II) and BioMnOx decreased HGT and mitigated resistance mutation by alleviating oxidative stress, which makes recipient cells more vulnerable to ARG acquisition and mutation. A manganese bio-oxidation based reactor was constructed and completely removed tetracycline with environmental concentration within 4-hour hydraulic retention time. Overall, this study suggests that Mn (II) bio-oxidation process could be exploited to control antibiotic contamination and mitigate resistance propagation during water treatment.
Topics: Manganese; Anti-Bacterial Agents; Escherichia coli; Oxidation-Reduction; Oxides; Manganese Compounds; Tetracycline
PubMed: 37549546
DOI: 10.1016/j.watres.2023.120442 -
BMC Public Health Dec 2023In general, a slightly higher number of boys are born than girls, and the sex ratio at birth (number of male births/number of female births) is reported to be 1.03-1.07...
BACKGROUND
In general, a slightly higher number of boys are born than girls, and the sex ratio at birth (number of male births/number of female births) is reported to be 1.03-1.07 in many countries. However, pregnant women exposed to high levels of atmospheric particulate matter have a reduced sex ratio at birth. Exposure to air pollutants can also lead to premature birth, suggesting that inflammation within the body may affect pregnancy maintenance and fetal development. On the other hand, the effects of air pollutants carried from afar by monsoons on the sex ratio at birth in downstream areas have not been evaluated. We focused on the Goto Islands, where various air pollutants flow from the Eurasian continent. The objective of this study was to clarify the effects of the atmospheric level of each pollutant on the sex ratio at birth on the Goto Islands.
METHODS
We extracted observation data of particulate matter 2.5, sulfur dioxide, oxidants, nonmethane hydrocarbons, and methane from the National Institute for Environmental Studies database. In addition, the monthly sex ratio at birth was calculated using birth data from the National Statistics Center. To evaluate the effect of substance exposure just before fertilization on the sex ratio at birth, we analyzed the relationship between the observed pollutant level and the sex ratio at birth 9 months later. A stepwise generalized linear model was used to analyze the effects of air pollutant levels on the sex ratio at birth.
RESULTS
The observed values for all pollutants were significantly different between seasons, including the particulate matter 2.5 (p < 0.0001), sulfur dioxide (p = 0.0026), oxidant (p < 0.0001), nonmethane hydrocarbon (p < 0.0001), and methane (p < 0.0001) values. In the target population in the target period, the total number of births was 1835, and the sex ratio at birth was 0.967. Univariate analysis showed that the values of particulate matter 2.5 (p = 0.0157) and oxidants (p = 0.0047) correlated negatively with the sex ratio at birth. In addition, the results of multivariate analysis using the stepwise method in the model equation indicated that every 1 ppm increase in the observed OX value resulted in a 0.311 decrease in the sex ratio at birth (p = 0.0034).
CONCLUSIONS
We evaluated the relationship between seasonal variations in air pollutant levels and the sex ratio at birth 9 months later on the Goto Islands. We found that an increase in oxidant levels just before and after conception may be a risk factor for a lower sex ratio at birth. Due to the previously reported vulnerability of male fetuses, females who become pregnant when air pollutant concentrations are high may be more likely to have a female baby. It is necessary to evaluate the effects of oxidants on various aspects of pregnancy and childbirth.
Topics: Infant, Newborn; Female; Male; Humans; Pregnancy; Air Pollutants; Seasons; Sulfur Dioxide; Air Pollution; Japan; Sex Ratio; Particulate Matter; Oxidants; Methane
PubMed: 38082405
DOI: 10.1186/s12889-023-17418-5 -
Journal of Environmental Sciences... Sep 2023Manganese-based catalysts were widely developed for catalytic removal of ozone, and the low stability and water inactivation are major challenges. To improve removal...
Manganese-based catalysts were widely developed for catalytic removal of ozone, and the low stability and water inactivation are major challenges. To improve removal performance of ozone, three methods were applied to modify amorphous manganese oxides, including acidification, calcination and Ce modification. The physiochemical properties of prepared samples were characterized, and the catalytic activity for ozone removal was evaluated. All modification methods can promote the removal of ozone by amorphous manganese oxides, and Ce modification showed the most significant enhancement. It was confirmed that the introduction of Ce markedly changed the amount and property of oxygen vacancies in amorphous manganese oxides. Superior catalytic activity of Ce-MnO can be ascribed to its more content and enhanced formation ability of oxygen vacancies, larger specific surface area and higher oxygen mobility. Furthermore, the durability tests under high relative humidity (80%) determined that Ce-MnO showed excellent stability and water resistance. These demonstrate the promising potential of amorphously Ce-modified manganese oxides for catalytic removal of ozone.
Topics: Manganese; Ozone; Oxygen; Oxides; Water
PubMed: 37225376
DOI: 10.1016/j.jes.2022.08.021 -
Applied and Environmental Microbiology Aug 2023An important role of nitric oxide (NO) as either a free intermediate in the NH oxidation pathway or a potential oxidant for NH or NHOH has been proposed for...
An important role of nitric oxide (NO) as either a free intermediate in the NH oxidation pathway or a potential oxidant for NH or NHOH has been proposed for ammonia-oxidizing bacteria (AOB) and archaea (AOA), respectively. However, tracing NO metabolism at low concentrations remains notoriously difficult. Here, we use electrochemical sensors and the mild NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) to trace apparent NO concentration and determine production rates at low micromolar concentrations in the model AOB strain Nitrosomonas europaea. In agreement with previous studies, we found that PTIO does not affect NH oxidation instantaneously in both Nitrosospira briensis and Nitrosomonas europaea, unlike inhibitors for ammonia oxidation such as allylthiourea and acetylene, although it effectively scavenged NO from the cell suspensions. Quantitative analysis showed that NO production by amounted to 3.15% to 6.23% of NO production, whereas grown under O limitation produced NO equivalent to up to 40% of NO production at high substrate concentrations. In addition, we found that PTIO addition to grown under O limitation abolished NO production. These results indicate different turnover rates of NO during NH oxidation under O-replete and O-limited growth conditions in AOB. The results suggest that NO may not be a free intermediate or remain tightly bound to iron centers of enzymes during hydroxylamine oxidation and that only NH saturation and adaptation to O limitation may lead to significant dissociation of NO from hydroxylamine dehydrogenase. Ammonia oxidation by chemolithoautotrophic ammonia-oxidizing bacteria (AOB) is thought to contribute significantly to global nitrous oxide (NO) emissions and leaching of oxidized nitrogen, particularly through their activity in nitrogen (N)-fertilized agricultural production systems. Although substantial efforts have been made to characterize the N metabolism in AOB, recent findings suggest that nitric oxide (NO) may play an important mechanistic role as a free intermediate of hydroxylamine oxidation in AOB, further implying that besides hydroxylamine dehydrogenase (HAO), additional enzymes may be required to complete the ammonia oxidation pathway. However, the NO spin trap PTIO was found to not inhibit ammonia oxidation in AOB. This study provides a combination of physiological and spectroscopic evidence that PTIO indeed scavenges only free NO in AOB and that significant amounts of free NO are produced only during incomplete hydroxylamine oxidation or nitrifier denitrification under O-limited growth conditions.
Topics: Nitric Oxide; Ammonia; Hydroxylamine; Nitrogen Dioxide; Oxidation-Reduction; Nitrous Oxide; Archaea; Betaproteobacteria; Nitrogen; Hydroxylamines; Nitrification
PubMed: 37439697
DOI: 10.1128/aem.02173-22 -
Journal of Environmental Management Jan 2024Chromite oxidative dissolution has been recognized as an important process leading to elevated Cr(VI) in soil and groundwater. Under natural conditions, direct oxidation...
Chromite oxidative dissolution has been recognized as an important process leading to elevated Cr(VI) in soil and groundwater. Under natural conditions, direct oxidation of Cr(III) by O is very unfavorable, and a critical determinant of Cr(VI) generation in soil and groundwater is the interaction between chromite and Mn(II) or Mn(III/IV) oxides. Here, the effects of Mn(II) or Mn(IV) on the oxidative dissolution of chromite were investigated at pH values of 5, 7 and 9 during anoxic, oxic and anoxic-oxic processes. The results showed that the direct oxidation of Cr(III) by O was slow in aqueous-phase system, while the Mn oxides in chromite could oxidize dissolved Cr(III). The added Mn(II) can be catalytically oxidized to MnOOH on the chromite surface only under alkaline oxidation conditions, and the catalytic efficiency is slow, which has less effect on chromite oxidative dissolution. Compared with the direct oxidation of O and catalytic oxidation of Mn(II), the synthesized biogenic Mn oxides drove the oxidative dissolution of chromite to release more Cr(VI) and were the main threat to the long-term stability of chromite in the environment. Overall, both acidic and alkaline environments are favorable to the catalytic oxidation of chromite by O, Mn(II) and δ-MnO, while neutral conditions are favorable to the long-term stability of chromite. These above processes may occur in soils and sediments with redox fluctuations (e.g., rice paddies, river floodplains, wetlands, and peatlands), and the presence of Mn(II) and Mn(III/IV) may play an important role in the oxidation and mobilization of Cr(III), leading to elevated Cr(VI) levels in soils and groundwater.
Topics: Oxides; Manganese Compounds; Oxidation-Reduction; Chromium; Soil; Hydrogen-Ion Concentration
PubMed: 37922821
DOI: 10.1016/j.jenvman.2023.119475 -
Chemosphere Nov 2023This study upgrades the sustainability of environmental electrochemical technologies with a novel approach consisting of the in-situ cogeneration and use of two...
This study upgrades the sustainability of environmental electrochemical technologies with a novel approach consisting of the in-situ cogeneration and use of two important oxidants, hydrogen peroxide (HO) and Caro's acid (HSO), manufactured with the same innovative cell. This reactor was equipped with a gas diffusion electrode (GDE) to generate cathodically HO, from oxygen reduction reaction, a boron doped diamond (BDD) electrode to obtain HSO, via anodic oxidation of dilute sulfuric acid, and a proton exchange membrane to separate the anodic and the cathodic compartment, preventing the scavenging effect of the interaction of oxidants. A special design of the inlet helps this cell to reach simultaneous efficiencies as high as 99% for HO formation and 19.7% for Caro's acid formation, which means that the cogeneration reaches efficiencies over 100% in the uses of electric current to produce oxidants. The two oxidants' streams produced were used with different configurations for the degradation of three volatile organic compounds (benzene, toluene, and xylene) in a batch reactor equipped with a UVC-lamp. Among different alternatives studied, the combination HSO/HO under UVC irradiation showed the best results in terms of degradation efficiency, demonstrating important synergisms as compared to the bare technologies.
Topics: Oxidants; Hydrogen Peroxide; Oxidation-Reduction; Electrodes; Boron; Diamond; Water Pollutants, Chemical
PubMed: 37714487
DOI: 10.1016/j.chemosphere.2023.140171 -
Luminescence : the Journal of... Feb 2024Biological oxidants participate in many processes in the human body. Their excessive production causes organelle damage, which may result in the accumulation of...
Biological oxidants participate in many processes in the human body. Their excessive production causes organelle damage, which may result in the accumulation of cytotoxic mediators and cell degradation and may manifest itself in various diseases. Peroxynitrite (ONOO ), hypochlorous acid (HOCl), hydrogen peroxide (H O ), and peroxymonocarbonate (HOOCO ) are important oxidants in biology, toxicology, and various pathologies. Derivatives of coumarin, containing an oxidant-sensitive boronate group, have been recently developed for the fluorescent detection of inflammatory oxidants. Here, we report the synthesis and characterization of 4-[2-(morpholin-4-yl)-2-oxoethyl]-2-oxo-2H-chromen-7-yl boronic acid (MpC-BA) as a fluorescent probe for the detection of oxidants, with better solubility in water, high stability and fast response time toward peroxynitrite and hypochlorous acid. The effectiveness of the MpC-BA probe for the detection of peroxynitrite was measured by adding bolus ONOO or using the co-generating superoxide and nitrogen oxide system. MpC-BA is oxidized by ONOO to 7-hydroxy-4-[2-(morpholin-4-yl)-2-oxoethyl]-2H-chromen-2-one (MpC-OH). However, peroxynitrite-specific product (MpC-H) is formed in the minor reaction pathway. MpC-OH is also yielded in the reaction of MpC-BA with HOCl, and the subsequent formation of a chlorinated MpC-OH gives a specific product for HOCl (MpC-OHCl). H O slowly oxidizes MpC-BA. However, the addition of NaHCO increased the MpC-OH formation rate. We conclude that MpC-BA is potentially an improved fluorescent probe detecting peroxynitrite and hypochlorite in biological settings. Complementation of the fluorescence measurements by HPLC-based identification of chlorinated and reduced coumarin(s) will help identify the oxidants detected.
Topics: Humans; Oxidants; Fluorescent Dyes; Hypochlorous Acid; Peroxynitrous Acid; Oxidation-Reduction; Coumarins; Morpholines
PubMed: 38332465
DOI: 10.1002/bio.4685