Faculty Opinions recommendation of The impact of increased oxygen conditions on metal-contaminated sediments part I: effects on redox status, sediment geochemistry and metal bioavailability.

Plant-growth-promoting bacteria (PGPB) are gaining attention as a sustainable alternative to current agrochemicals. This study evaluated the impact of three Bacillus spp. (5PB1, 1PB1, FV46) and one Brevibacillus sp. (C9F) on the important crop tomato (Solanum lycopersicum) using the model cv. ‘MicroTom’. The effects of these isolates were assessed on (a) seedlings’ growth and vigor, and (b) adult potted plants. In potted plants, several photosynthetic parameters (chlorophylls (a and b), carotenoids and anthocyanins contents, transpiration rate, stomatal conductance, net CO2 photosynthetic rate, and intercellular CO2 concentration, and on chlorophyll fluorescence yields of light- and dark-adapted leaves)), as well as soluble sugars and starch contents, were quantified. Additionally, the effects on redox status were evaluated. While the growth of seedlings was, overall, not influenced by the strains, some effects were observed on adult plants. The Bacillus safensis FV46 stimulated the content of pigments, compared to C9F. Bacillus zhangzhouensis 5PB1 increased starch levels and was positively correlated with some parameters of the photophosphorylation and the gas exchange phases. Interestingly, Bacillus megaterium 1PB1 decreased superoxide (O2−) content, and B. safensis FV46 promoted non-enzymatic antioxidant defenses, increasing total phenol content levels. These results, conducted on a model cultivar, support the theory that these isolates differently act on tomato plant physiology, and that their activity depends on the age of the plant, and may differently influence photosynthesis. It would now be interesting to analyze the influence of these bacteria using commercial cultivars.

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Imaging NAD(H) Redox Alterations in Cryopreserved Alveolar Macrophages from Ozone-Exposed Mice and the Impact of Nutrient Starvation during Long Lag Times

Antioxidants ◽

10.3390/antiox10050767 ◽

2021 ◽

Vol 10 (5) ◽

pp. 767

Author(s):

He N. Xu ◽

Joanna Floros ◽

Lin Z. Li ◽

Shaili Amatya

Keyword(s):

Oxidative Stress ◽

Alveolar Macrophages ◽

Redox State ◽

Redox Status ◽

Nutrient Starvation ◽

Ozone Exposure ◽

Reduced Form ◽

Time Period ◽

Lag Times ◽

The Impact

Employing the optical redox imaging technique, we previously identified a significant redox shift of nicotinamide adenine dinucleotide (NAD and the reduced form NADH) in freshly isolated alveolar macrophages (AM) from ozone-exposed mice. The goal here was twofold: (a) to determine the NAD(H) redox shift in cryopreserved AM isolated from ozone-exposed mice and (b) to investigate whether there is a difference in the redox status between cryopreserved and freshly isolated AM. We found: (i) AM from ozone-exposed mice were in a more oxidized redox state compared to that from filtered air (FA)-exposed mice, consistent with the results obtained from freshly isolated mouse AM; (ii) under FA exposure, there was no significant NAD(H) redox difference between fresh AM that had been placed on ice for 2.5 h and cryopreserved AM; however, under ozone exposure, fresh AM were more oxidized than cryopreserved AM; (iii) via the use of nutrient starvation and replenishment and H2O2-induced oxidative stress of an AM cell line, we showed that this redox difference between cryopreserved and freshly isolated AM is likely the result of the double “hit”, i.e., the ozone-induced oxidative stress plus nutrient starvation that prevented freshly isolated AM from a full recovery after being on ice for a prolonged time period. The cryopreservation technique we developed eliminates/minimizes the effects of oxidative stress and nutrient starvation on cells. This method can be adopted to preserve lung macrophages from animal models or clinical patients for further investigations.

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Oxygen-Dependent Changes in the N-Glycome of Murine Pulmonary Endothelial Cells

Antioxidants ◽

10.3390/antiox10121947 ◽

2021 ◽

Vol 10 (12) ◽

pp. 1947

Author(s):

Akos Tiboldi ◽

Johannes Führer ◽

Wolfgang Schaubmayr ◽

Eva Hunyadi-Gulyas ◽

Marie Louise Zach ◽

...

Keyword(s):

Molecular Mechanisms ◽

Lectin Binding ◽

Supplemental Oxygen ◽

Redox Status ◽

Blood Oxygenation ◽

Glycan Structure ◽

Pulmonary Endothelium ◽

Proteomic Approach ◽

Oxygen Conditions

Supplemental oxygen is frequently used together with mechanical ventilation to achieve sufficient blood oxygenation. Despite the undoubted benefits, it is vigorously debated whether too much oxygen can also have unpredicted side-effects. Uncertainty is also due to the fact that the molecular mechanisms are still insufficiently understood. The lung endothelium is covered with an exceptionally broad glycocalyx, carrying N- and O-glycans, proteoglycans, glycolipids and glycosaminoglycans. Glycan structures are not genetically determined but depend on the metabolic state and the expression level and activity of biosynthetic and glycan remodeling enzymes, which can be influenced by oxygen and the redox status of the cell. Altered glycan structures can affect cell interactions and signaling. In this study, we investigated the effect of different oxygen conditions on aspects of the glycobiology of the pulmonary endothelium with an emphasis on N-glycans and terminal sialylation using an in vitro cell culture system. We combined a proteomic approach with N-glycan structure analysis by LC-MS, qRT-PCR, sialic acid analysis and lectin binding to show that constant and intermittent hyperoxia induced time dependent changes in global and surface glycosylation. An siRNA approach identified St6gal1 as being primarily responsible for the early transient increase of α2-6 sialylated structures in response to hyperoxia.

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Mineral Micronutrients in Asthma

Nutrients ◽

10.3390/nu13114001 ◽

2021 ◽

Vol 13 (11) ◽

pp. 4001

Author(s):

Dominika Zajac

Keyword(s):

Oxidative Stress ◽

Risk Factors ◽

Air Pollution ◽

Defense Mechanisms ◽

Redox Status ◽

Chronic Inflammatory Disease ◽

Modern World ◽

Medical Issues ◽

Persistent Inflammation ◽

The Impact

Asthma represents one of the most common medical issues in the modern world. It is a chronic inflammatory disease characterized by persistent inflammation of the airways and disturbances in redox status, leading to hyperresponsiveness of bronchi and airway obstruction. Apart from classical risk factors such as air pollution, family history, allergies, or obesity, disturbances of the levels of micronutrients lead to impairments in the defense mechanisms of the affected organism against oxidative stress and proinflammatory stimuli. In the present review, the impact of micronutrients on the prevalence, severity, and possible risk factors of asthma is discussed. Although the influence of classical micronutrients such as selenium, copper, or zinc are well known, the effects of those such as iodine or manganese are only rarely mentioned. As a consequence, the aim of this paper is to demonstrate how disturbances in the levels of micronutrients and their supplementation might affect the course of asthma.

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Diagenetic formation of uranium-silica polymers in lake sediments over 3,300 years

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2021844118 ◽

2021 ◽

Vol 118 (4) ◽

pp. e2021844118

Author(s):

Pierre Lefebvre ◽

Alkiviadis Gourgiotis ◽

Arnaud Mangeret ◽

Pierre Sabatier ◽

Pierre Le Pape ◽

...

Keyword(s):

Contaminated Sediments ◽

Mining Areas ◽

Subsurface Environments ◽

Geochemical Reactivity ◽

High Silica ◽

Long Term Behavior ◽

The Impact ◽

X Ray Absorption

The long-term fate of uranium-contaminated sediments, especially downstream former mining areas, is a widespread environmental challenge. Essential for their management is the proper understanding of uranium (U) immobilization mechanisms in reducing environments. In particular, the long-term behavior of noncrystalline U(IV) species and their possible evolution to more stable phases in subsurface conditions is poorly documented, which limits our ability to predict U long-term geochemical reactivity. Here, we report direct evidence for the evolution of U speciation over 3,300 y in naturally highly U-enriched sediments (350–760 µg ⋅ g−1 U) from Lake Nègre (Mercantour Massif, Mediterranean Alps, France) by combining U isotopic data (δ238U and (234U/238U)) with U L3-edge X-ray absorption fine structure spectroscopy. Constant isotopic ratios over the entire sediment core indicate stable U sources and accumulation modes, allowing for determination of the impact of aging on U speciation. We demonstrate that, after sediment deposition, mononuclear U(IV) species associated with organic matter transformed into authigenic polymeric U(IV)–silica species that might have partially converted to a nanocrystalline coffinite (UIVSiO4·nH2O)-like phase. This diagenetic transformation occurred in less than 700 y and is consistent with the high silica availability of sediments in which diatoms are abundant. It also yields consistency with laboratory studies that proposed the formation of colloidal polynuclear U(IV)–silica species, as precursors for coffinite formation. However, the incomplete transformation observed here only slightly reduces the potential lability of U, which could have important implications to evaluate the long-term management of U-contaminated sediments and, by extension, of U-bearing wastes in silica-rich subsurface environments.

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Safranal Attenuates Excitotoxin-Induced Oxidative OLN-93 Cells Injury

Drug Research ◽

10.1055/a-0790-8200 ◽

2018 ◽

Vol 69 (06) ◽

pp. 323-329 ◽

Cited By ~ 2

Author(s):

Mohaddeseh Sadat Alavi ◽

Sahar Fanoudi ◽

Ameneh Veisi Fard ◽

Mohammad Soukhtanloo ◽

Mahmoud Hosseini ◽

...

Keyword(s):

Cell Viability ◽

Toxic Effect ◽

Redox Status ◽

Demyelinating Diseases ◽

Crocus Sativus ◽

Oxygen Species ◽

Pharmacological Effects ◽

Active Constituent ◽

Ros Accumulation ◽

The Impact

Abstract Objectives Researches have been shown that glutamic acid (GA) or quinolinic acid (QA) can play role in neuroinflammatory and demyelinating diseases including multiple sclerosis (MS), mainly via oligodendrocytes activation and extreme free radicals generation. Recent studies have demonstrated that safranal, an active constituent of Crocus sativus, has several pharmacological effects such as antioxidant, anti-inflammatory and neuroprotective properties. Since there is no data about the impact of safranal on MS, this study was designed to investigate the protective effect of safranal on OLN-93 oligodendrocytes injury induced by GA or QA. Materials and Methods At first, the potential toxic effect of safranal on OLN-93 viability was evaluated. Also, the cells were pretreated with safranal (0.1, 1, 10, 50, 100 and 200 μM) for 2 h and then subjected to GA (16 mM) or QA (8 mM) toxicity for 24 h, in which the same treatments were applied. The cell viability and parameters of redox status such as the levels of intracellular reactive oxygen species (ROS) and lipid peroxidation were measured. Results Safranal at concentration ranges of 1–800 μM had no toxic effect on cell viability (p>0.05). Treatment with safranal significantly increased cell viability following GA or QA insults at concentrations higher than 1 μM (p<0.01). The cytoprotective potential of safranal was also accompanied by decreased ROS accumulation (p<0.001) and malondialdehyde level (p<0.001) following GA or QA insults. Conclusion The data suggests that safranal exhibits oligoprotection potential by means of inhibiting oxidative stress parameters.

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Buprenorphine and Methadone as Opioid Maintenance Treatments for Heroin-Addicted Patients Induce Oxidative Stress in Blood

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/9417048 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Christonikos Leventelis ◽

Nikolaos Goutzourelas ◽

Aikaterini Kortsinidou ◽

Ypatios Spanidis ◽

Georgia Toulia ◽

...

Keyword(s):

Oxidative Stress ◽

Thiobarbituric Acid ◽

Redox Status ◽

Protein Carbonyls ◽

Healthy Individuals ◽

Thiobarbituric Acid Reactive Substances ◽

Antioxidant Defence ◽

Total Antioxidant ◽

Beneficial Action ◽

The Impact

Buprenorphine and methadone are two substances widely used in the substitution treatment of patients who are addicted to opioids. Although it is known that they partly act efficiently towards this direction, there is no evidence regarding their effects on the redox status of patients, a mechanism that could potentially improve their action. Therefore, the aim of the present investigation was to examine the impact of buprenorphine and methadone, which are administered as substitutes to heroin-dependent patients on specific redox biomarkers in the blood. From the results obtained, both the buprenorphine (n=21) and the methadone (n=21) groups exhibited oxidative stress and compromised antioxidant defence. This was evident by the decreased glutathione (GSH) concentration and catalase activity in erythrocytes and the increased concentrations of thiobarbituric acid reactive substances (TBARS) and protein carbonyls in the plasma, while there was no significant alteration of plasma total antioxidant capacity (TAC) compared to the healthy individuals (n=29). Furthermore, methadone revealed more severe oxidant action compared to buprenorphine. Based on relevant studies, the tested substitutes mitigate the detrimental effects of heroin on patient redox status; still it appears that they need to be boosted. Therefore, concomitant antioxidant administration could potentially enhance their beneficial action, and most probably, buprenorphine that did not induce oxidative stress in such a severe mode as methadone, on the regulation of blood redox status.

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Looking beyond stratification: a model-based analysis of the biological drivers of oxygen deficiency in the North Sea

Biogeosciences ◽

10.5194/bg-13-2511-2016 ◽

2016 ◽

Vol 13 (8) ◽

pp. 2511-2535 ◽

Cited By ~ 21

Author(s):

Fabian Große ◽

Naomi Greenwood ◽

Markus Kreus ◽

Hermann-Josef Lenhart ◽

Detlev Machoczek ◽

...

Keyword(s):

North Sea ◽

Oxygen Deficiency ◽

Low Oxygen ◽

The North ◽

Oxygen Conditions ◽

Southern Central ◽

The North Sea ◽

Central North Sea ◽

The Impact ◽

Oxygen Dynamics

Abstract. Low oxygen conditions, often referred to as oxygen deficiency, occur regularly in the North Sea, a temperate European shelf sea. Stratification represents a major process regulating the seasonal dynamics of bottom oxygen, yet, lowest oxygen conditions in the North Sea do not occur in the regions of strongest stratification. This suggests that stratification is an important prerequisite for oxygen deficiency, but that the complex interaction between hydrodynamics and the biological processes drives its evolution. In this study we use the ecosystem model HAMSOM-ECOHAM to provide a general characterisation of the different zones of the North Sea with respect to oxygen, and to quantify the impact of the different physical and biological factors driving the oxygen dynamics inside the entire sub-thermocline volume and directly above the bottom. With respect to oxygen dynamics, the North Sea can be subdivided into three different zones: (1) a highly productive, non-stratified coastal zone, (2) a productive, seasonally stratified zone with a small sub-thermocline volume, and (3) a productive, seasonally stratified zone with a large sub-thermocline volume. Type 2 reveals the highest susceptibility to oxygen deficiency due to sufficiently long stratification periods (>  60 days) accompanied by high surface productivity resulting in high biological consumption, and a small sub-thermocline volume implying both a small initial oxygen inventory and a strong influence of the biological consumption on the oxygen concentration. Year-to-year variations in the oxygen conditions are caused by variations in primary production, while spatial differences can be attributed to differences in stratification and water depth. The large sub-thermocline volume dominates the oxygen dynamics in the northern central and northern North Sea and makes this region insusceptible to oxygen deficiency. In the southern North Sea the strong tidal mixing inhibits the development of seasonal stratification which protects this area from the evolution of low oxygen conditions. In contrast, the southern central North Sea is highly susceptible to low oxygen conditions (type 2). We furthermore show that benthic diagenetic processes represent the main oxygen consumers in the bottom layer, consistently accounting for more than 50 % of the overall consumption. Thus, primary production followed by remineralisation of organic matter under stratified conditions constitutes the main driver for the evolution of oxygen deficiency in the southern central North Sea. By providing these valuable insights, we show that ecosystem models can be a useful tool for the interpretation of observations and the estimation of the impact of anthropogenic drivers on the North Sea oxygen conditions.

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