Carotenoids as a Protection Mechanism against Oxidative Stress in Haloferax mediterranei

Haloarchaea are extremophilic microorganisms that in their natural ecosystem encounter several sources of oxidative stress. They have developed different strategies to cope with these harsh environmental conditions, among which bacterioruberin production is a very notable strategy. Bacterioruberin (BR) is a C50 carotenoid synthesized in response to different types of stress. Previous works demonstrated that it shows interesting antioxidant properties with potential applications in biotechnology. In this study, Haloferax mediterranei strain R-4 was exposed to different concentrations of the oxidant compound H2O2 to evaluate the effect on carotenoid production focusing the attention on the synthesis of bacterioruberin. Hfx. mediterranei was able to grow in the presence of H2O2 from 1 mM to 25 mM. Cells produced between 16% and 78% (w/v) more carotenoids under the induced oxidative stress compared to control cultures. HPLC-MS analysis detected BR as the major identified carotenoid and confirmed the gradual increase of BR content as higher concentrations of hydrogen peroxide were added to the medium. These results shed some light on the biological role of bacterioruberin in haloarchaea, provide interesting information about the increase of the cellular pigmentation under oxidative stress conditions and will allow the optimization of the production of this pigment at large scale using these microbes as biofactories.

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Situational Breakdowns

10.1093/oso/9780190922061.001.0001 ◽

2019 ◽

Cited By ~ 8

Author(s):

Anne Nassauer

Keyword(s):

United States ◽

Large Scale ◽

Contextual Factors ◽

The United States ◽

Social Outcomes ◽

Dynamic Processes ◽

Collective Decisions ◽

Different Types ◽

The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

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Protective Role of Natural and Semi-Synthetic Tocopherols on TNFα-Induced ROS Production and ICAM-1 and Cl-2 Expression in HT29 Intestinal Epithelial Cells

Antioxidants ◽

10.3390/antiox10020160 ◽

2021 ◽

Vol 10 (2) ◽

pp. 160

Author(s):

Vladana Domazetovic ◽

Irene Falsetti ◽

Caterina Viglianisi ◽

Kristian Vasa ◽

Cinzia Aurilia ◽

...

Keyword(s):

Oxidative Stress ◽

Antioxidant Properties ◽

Intestinal Barrier ◽

Protective Role ◽

Intercellular Adhesion Molecule ◽

Intestinal Epithelial ◽

Intercellular Adhesion Molecule 1 ◽

Beneficial Effects ◽

Bowel Diseases

Vitamin E, a fat-soluble compound, possesses both antioxidant and non-antioxidant properties. In this study we evaluated, in intestinal HT29 cells, the role of natural tocopherols, α-Toc and δ-Toc, and two semi-synthetic derivatives, namely bis-δ-Toc sulfide (δ-Toc)2S and bis-δ-Toc disulfide (δ-Toc)2S2, on TNFα-induced oxidative stress, and intercellular adhesion molecule-1 (ICAM-1) and claudin-2 (Cl-2) expression. The role of tocopherols was compared to that of N-acetylcysteine (NAC), an antioxidant precursor of glutathione synthesis. The results show that all tocopherol containing derivatives used, prevented TNFα-induced oxidative stress and the increase of ICAM-1 and Cl-2 expression, and that (δ-Toc)2S and (δ-Toc)2S2 are more effective than δ-Toc and α-Toc. The beneficial effects demonstrated were due to tocopherol antioxidant properties, but suppression of TNFα-induced Cl-2 expression seems not only to be related with antioxidant ability. Indeed, while ICAM-1 expression is strongly related to the intracellular redox state, Cl-2 expression is TNFα-up-regulated by both redox and non-redox dependent mechanisms. Since ICAM-1 and Cl-2 increase intestinal bowel diseases, and cause excessive recruitment of immune cells and alteration of the intestinal barrier, natural and, above all, semi-synthetic tocopherols may have a potential role as a therapeutic support against intestinal chronic inflammation, in which TNFα represents an important proinflammatory mediator.

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Acute Stress Induced Behavioral Deficits In Rats: Relationship With Oxidative Stress, Leptin And HPA Axis

Journal of the chemical society of pakistan ◽

10.52568/000804/jcsp/41.05.2019 ◽

2019 ◽

Vol 41 (5) ◽

pp. 859-859

Author(s):

Erum Shireen Erum Shireen ◽

Wafa Binte Ali Wafa Binte Ali ◽

Maria Masroor Maria Masroor ◽

Saeeda Bano Saeeda Bano ◽

Samina Iqbal Samina Iqbal ◽

...

Keyword(s):

Oxidative Stress ◽

Open Field ◽

Hpa Axis ◽

Acute Stress ◽

Antioxidant Properties ◽

Oxidative Enzymes ◽

Behavioral Deficits ◽

Glucose Estimation ◽

Dark Transition

Acute exposure to stress is connected to many disorders that promote the toxicity of oxygen radical generators leading to increase in the levels of enzymes and also the activation of the HPA axis. The present study uses a preclinical approach to elucidate some prospective stress-induced behavioral and biochemical effects. The aim of current study was to investigate the relationship between stress and behavioral changes after exposing animals to 2h immobilization stress. We also evaluated the concentration of corticosterone, glucose and endogenous leptin levels in unstressed and stressed animals to explore the possible role of HPA axis in the modulation of stressed induced behavioral deficits. Rats were divided into stressed and unstressed groups. Behavioral activities were monitored in open field activity and light dark transition box after the termination of 2h immobilization period. Animals were then decapitated and plasma samples were collected for catalase, SOD, corticosterone, and glucose estimation. Results showed that exposure to acute stress produced a significant decrease in the activity of rats in the novel environment (open field) and light dark transition box. On the other hand, concomitant elevated level of peripheral markers of oxidative stress such as oxidative enzymes, corticosterone and endogenous leptin were also observed. Therefore, current study seems to suggest an important role of compounds having antioxidant properties for the treatment of stress and related disorders.

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ON THE CHARACTERISTICS OF INNOVATIVE FIRMS IN KOREA: THE ROLE OF R&D AND INNOVATION TYPE

International Journal of Innovation Management ◽

10.1142/s1363919699000062 ◽

1999 ◽

Vol 03 (01) ◽

pp. 111-131 ◽

Cited By ~ 11

Author(s):

YONG-TAE PARK ◽

CHUL-HYUN KIM ◽

JI-HYO LEE

Keyword(s):

Large Scale ◽

Data Gathering ◽

Policy Implications ◽

Future Research ◽

Different Types ◽

Innovative Firms ◽

Unexpected Findings ◽

Innovation Type ◽

Recent Extension

In spite of the recent extension of our knowledge on technological innovation, little inquiry has been made of the distinctive characteristics between R&D firms and non-R&D firms, as well as between product-innovative firms and process-innovative firms. To this end, the main objective of this empirical study, grounded on a large-scale innovation survey of Korean manufacturing firms, is to contrast these two types of firms. The results were mixed. Some hypotheses were confirmed while others were discordant with expectation. By and large, R&D firms and product-innovative firms seem to share a similar propensity, whereas non-R&D firms and process-innovative firms are alike in character. However, there were some unexpected findings which merit attention and are worthy of in-depth examination. Although the study is subject to limitations in terms of its research design and data gathering, the results render some important policy implications. Furthermore, comparative analyses between different types of innovations need to be addressed more extensively in future research.

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In Vitro Study of Antioxidant Activity of Serum and Plasma Samples As Well As Glutathione Exposed to Various Exogenous Stress Factors

10.21203/rs.3.rs-630921/v1 ◽

2021 ◽

Author(s):

Małgorzata Olszowy-Tomczyk ◽

Łukasz Paprotny ◽

Agnieszka Celejewska ◽

Dorota Szewczak ◽

Dorota Wianowska

Keyword(s):

Oxidative Stress ◽

Antioxidant Activity ◽

Antioxidant Properties ◽

In Vitro Study ◽

Stress Factors ◽

Plasma Samples ◽

Serum Samples ◽

Exogenous Stress

Abstract The imbalance between the production of Reactive Oxygen Species (ROS) and their sequestration promotes the formation of so-called oxidative stress conditions which are considered crucial in the aging process and development of many human diseases. Glutathione plays an essential role in the antioxidative barricade against ROS. Its role in the detoxification process of xenobiotics and carcinogen is also known. However, there are no comparative studies on the antioxidant properties of both biological samples and glutathione as well as the change in these properties as a result of exposure to various stress factors. This paper fills this gap comparing the antioxidant activity of serum and plasma samples of the known glutathione content with the activity of glutathione itself assessed by the different methods. In addition, it reveals a significant role of environmental xenobiotics in oxidative stress and differentiates the stress induced by different groups of drugs, among which the greatest one has been demonstrated for antiarrhythmic drugs and cytostatics. More importantly, it proves that human plasma is more resistant to stress factors and N-acetylcysteine clearly promotes the extension of antioxidant properties of both the plasma and serum samples. The latter conclusion is consistent with the implied preventive and/or supportive action of this drug against SARS-CoV-2.

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Oxidative Stress and Marine Carotenoids: Application by Using Nanoformulations

Marine Drugs ◽

10.3390/md18080423 ◽

2020 ◽

Vol 18 (8) ◽

pp. 423 ◽

Cited By ~ 3

Author(s):

Yasin Genç ◽

Hilal Bardakci ◽

Çiğdem Yücel ◽

Gökçe Şeker Karatoprak ◽

Esra Küpeli Akkol ◽

...

Keyword(s):

Oxidative Stress ◽

Antioxidant Properties ◽

Chemical Diversity ◽

Biologically Active ◽

Bioactive Molecules ◽

Photosynthetic Organisms ◽

Stress Markers ◽

Potential Applications ◽

Health Promoting ◽

Cancer Types

Carotenoids are natural fat-soluble pigments synthesized by plants, algae, fungi and microorganisms. They are responsible for the coloration of different photosynthetic organisms. Although they play a role in photosynthesis, they are also present in non-photosynthetic plant tissues, fungi, and bacteria. These metabolites have mainly been used in food, cosmetics, and the pharmaceutical industry. In addition to their utilization as pigmentation, they have significant therapeutically applications, such as improving immune system and preventing neurodegenerative diseases. Primarily, they have attracted attention due to their antioxidant activity. Several statistical investigations indicated an association between the use of carotenoids in diets and a decreased incidence of cancer types, suggesting the antioxidant properties of these compounds as an important factor in the scope of the studies against oxidative stress. Unusual marine environments are associated with a great chemical diversity, resulting in novel bioactive molecules. Thus, marine organisms may represent an important source of novel biologically active substances for the development of therapeutics. Marine carotenoids (astaxanthin, fucoxanthin, β-carotene, lutein but also the rare siphonaxanthin, sioxanthin, and myxol) have recently shown antioxidant properties in reducing oxidative stress markers. Numerous of bioactive compounds such as marine carotenoids have low stability, are poorly absorbed, and own very limited bioavailability. The new technique is nanoencapsulation, which can be used to preserve marine carotenoids and their original properties during processing, storage, improve their physiochemical properties and increase their health-promoting effects. This review aims to describe the role of marine carotenoids, their potential applications and different types of advanced nanoformulations preventing and treating oxidative stress related disorders.

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Effect of Blueberry Anthocyanins Malvidin and Glycosides on the Antioxidant Properties in Endothelial Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/1591803 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 31

Author(s):

Wuyang Huang ◽

Yunming Zhu ◽

Chunyang Li ◽

Zhongquan Sui ◽

Weihong Min

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Endothelial Cells ◽

Functional Food ◽

Functional Role ◽

Antioxidant Properties ◽

Heme Oxygenase 1 ◽

Oxygen Species ◽

Good Resource

The objective of this research was to survey the antioxidant functional role of the main anthocyanins of blueberries in endothelial cells. Changes on the reactive oxygen species (ROS), xanthine oxidase-1 (XO-1), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) in cells of malvidin and the two glycosides were investigated. The results showed that these anthocyanins decreased the levels of ROS and XO-1 but increased the levels of SOD and HO-1. Glycosides improved the antioxidant capacity of malvidin to a great extent. The changes in the antioxidant properties of malvidin-3-glucoside were more pronounced than malvidin-3-galactoside. Variation in levels of malvidin-3-glucoside and malvidin-3-galactoside had a significant impact on antioxidant properties to different extents. It indicates that blueberries are a good resource of anthocyanins, which can protect cells from oxidative deterioration and use blueberry as a potential functional food to prevent diseases related to oxidative stress.

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Melatonin Modulation of Sirtuin-1 Attenuates Liver Injury in a Hypercholesterolemic Mouse Model

BioMed Research International ◽

10.1155/2018/7968452 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 11

Author(s):

Francesca Bonomini ◽

Gaia Favero ◽

Luigi Fabrizio Rodella ◽

Mohammed H. Moghadasian ◽

Rita Rezzani

Keyword(s):

Oxidative Stress ◽

Biochemical Markers ◽

Antioxidant Properties ◽

Sirtuin 1 ◽

Oral Supplementation ◽

Stress Markers ◽

Serum Biochemical ◽

Stress Signals

Hypercholesterolemia increases and exacerbates stress signals leading also to liver damage (LD) and failure. Sirtuin1 (SIRT1) is involved in lifespan extension and it plays an essential role in hepatic lipid metabolism. However, its involvement in liver hypercholesterolemic damage is not yet completely defined. This in vivo study evaluated the role of SIRT1 in the hypercholesterolemic-related LD and, then, investigated how oral supplementation of melatonin, pleiotropic indoleamine, may be protective. Control mice and apolipoprotein E-deficient mice (ApoE−/−) of 6 and 15 weeks of age were treated or not treated with melatonin at the dose of 10 mg/kg/day for 9 weeks. In this study, we evaluated serum biochemical markers, liver SIRT1 expression, and oxidative stress markers. We observed that hypercholesterolemia increased significantly serum cholesterol and triglycerides, reduced significantly liver SIRT1, and, in turn, induced hepatic oxidative stress in untreated ApoE−/− mice with respect to control mice. Interestingly, melatonin treatment improved serum biochemical markers and hepatic morphological impairment and inhibited oxidative stress through its antioxidant properties and also by SIRT1 upregulation. In summary, melatonin oral supplementation may represent a new protective approach to block hypercholesterolemic liver alterations involving also a SIRT1-dependent mechanism.

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Antioxidant Properties of Bee Products Derived from Medicinal Plants as Beekeeping Sources

Agriculture ◽

10.3390/agriculture11111136 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1136

Author(s):

Alessandra Durazzo ◽

Massimo Lucarini ◽

Manuela Plutino ◽

Giuseppe Pignatti ◽

Ioannis K. Karabagias ◽

...

Keyword(s):

Oxidative Stress ◽

Medicinal Plants ◽

Royal Jelly ◽

Antioxidant Properties ◽

Natural Antioxidants ◽

Study Approach ◽

Potential Source ◽

Bee Foraging ◽

Medicinal Properties

Plant species are fundamental source of nectar in beekeeping since bees access nectar and pollen from flowers. Consequently, bee products are strongly linked to the bee foraging flora source, and, depending on this, they acquire defined features, including their health and medicinal properties. Medicinal plants contribute greatly to increase the beneficial properties of bee products, such as honey, pollen, royal jelly, and propolis. Bee products represent a potential source of natural antioxidants that can counteract the effects of oxidative stress underlying the pathogenesis of many diseases. The antioxidant properties of bee products have been widely studied and there is an abundance of information available in the literature. Notwithstanding, the uniqueness of the presented perspective is to provide an updated overview of the antioxidant properties of bee products derived from medicinal plants as beekeeping sources. This topic is divided and discussed in the text in different sections as follows: (i) beekeeping and the impacts of environmental factors; (ii) an overview of the role of medicinal plants for bee products; (iii) definition and categorization of the main medicinal bee plants and related bee products; (iv) the study approach of the antioxidant properties; (v) the conventional and innovative assays used for the measurement of the antioxidant activity; and (vi) the antioxidant properties of bee products from medicinal plants.

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Optimization of Growth and Carotenoid Production by Haloferax mediterranei Using Response Surface Methodology

Marine Drugs ◽

10.3390/md16100372 ◽

2018 ◽

Vol 16 (10) ◽

pp. 372 ◽

Cited By ~ 11

Author(s):

Zaida Montero-Lobato ◽

Adrián Ramos-Merchante ◽

Juan Fuentes ◽

Ana Sayago ◽

Ángeles Fernández-Recamales ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Large Scale ◽

Antioxidant Properties ◽

Carotenoid Content ◽

Scale Production ◽

Optimal Conditions ◽

Haloferax Mediterranei ◽

Carotenoid Production ◽

Total Carotenoid Content

Haloferax mediterranei produces C50 carotenoids that have strong antioxidant properties. The response surface methodology (RSM) tool helps to accurately analyze the most suitable conditions to maximize C50 carotenoids production by haloarchaea. The effects of temperature (15–50 °C), pH (4−10), and salinity (5–28% NaCl (w/v)) on the growth and carotenoid content of H. mediterranei were analyzed using the RSM approach. Growth was determined by measuring the turbidity at 600 nm. To determine the carotenoid content, harvested cells were lysed by freeze/thawing, then re-suspended in acetone and the total carotenoid content determined by measuring the absorbance at 494 nm. The analysis of carotenoids was performed by an HPLC system coupled with mass spectrometry. The results indicated the theoretical optimal conditions of 36.51 or 36.81 °C, pH of 8.20 or 8.96, and 15.01% or 12.03% (w/v) salinity for the growth of haloarchaea (OD600 = 12.5 ± 0.64) and production of total carotenoids (3.34 ± 0.29 mg/L), respectively. These conditions were validated experimentally for growth (OD600 = 13.72 ± 0.98) and carotenoid production (3.74 ± 0.20 mg/L). The carotenoid profile showed four isomers of bacterioruberin (89.13%). Our findings suggest that the RSM approach is highly useful for determining optimal conditions for large-scale production of bacterioruberin by haloarchaea.

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