RESUMEN

This review summarises the data from long-term experimental studies and literature data on the role of oxidatively modified low-density lipoproteins (LDL) in atherogenesis and diabetogenesis. It was shown that not "oxidized" (lipoperoxide-containing) LDL, but dicarbonyl-modified LDL are atherogenic (actively captured by cultured macrophages with the help of scavenger receptors), and also cause expression of lectin like oxidized low density lipoprotein receptor 1 (LOX-1) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 1 (NOX-1) genes in endotheliocytes, which stimulate apoptosis and endothelial dysfunction. The obtained data allowed us to justify new approaches to pharmacotherapy of atherosclerosis and diabetes mellitus.

RESUMEN

Human space activities have been continuously increasing. Astronauts experiencing spaceflight are faced with health problems caused by special space environments such as microgravity, and the investigation of cell injury is fundamental. The development of a platform capable of cell culture and injury detection is the prerequisite for the investigation. Constructing a platform suitable for special conditions in space life science research is the key issue. The ground-based investigation is an indispensable part of the research. Accordingly, a simulated microgravity (SMG)-oriented integrated chip platform capable of 3D cell culture and in situ visual detection of superoxide anion radical (O2•-) is developed. SMG can cause oxidative stress in human cells, and O2•- is one of the signaling molecules. Thus, a O2•--responsive aggregation-induced emission (AIE) probe is designed, which shows high selectivity and sensitivity to O2•-. Moreover, the probe exhibits abilities of long-term and wash-free staining to cells due to the AIE behavior, which is precious for space cell imaging. Meanwhile, a chip with a high-aspect-ratio chamber for adequate medium storage for the lack of the perfusion system during the SMG experiment and a cell culture chamber which can integrate the extracellular matrix (ECM) hydrogel for the bioinspired 3D cell culture is fabricated. In addition, a porous membrane is introduced between the chambers to prevent the hydrogel from separating during the SMG experiment. The afforded AIE probe-ECM hydrogel-integrated chip can achieve 3D culturing of U87-MG cells and in situ fluorescent detection of endogenous O2•- in the cells after long-term staining under SMG. The chip provides a powerful and potential platform for ground-based investigation in space life science and biomedical research.

Asunto(s)

RESUMEN

Opuntia plants are abundant but still underexplored edible resources of the Algerian region. This work chemically characterizes extracts of different parts of the fruit of the commercial Opuntia ficus-indica (L.) Mill. and the wild Opuntia stricta (Haw.) Haw. growing in Bejaia, and evaluates their anti-inflammatory potential through different cell and cell-free bioassays. The LC-ESI-UHR-QqTOF-MS/MS analysis enabled the identification of 18 compounds, with azelaic acid and 1-O-vanilloyl-ß-d-glucose reported here for the first time. Aqueous extracts of seeds were the most effective in scavenging superoxide anion radical (IC50 = 111.08 µg/mL) and presented the best anti-inflammatory potential in LPS-stimulated macrophages (IC50 = 206.30 µg/mL). The pulp of O. stricta suggested potential for addressing post-inflammatory hyperpigmentation, with piscidic and eucomic acids predicted with the strongest binding affinity towards tyrosinase, exhibiting higher scoring values than the reference inhibitor kojic acid. This pioneer study brings valuable perspectives for the pharmacological, nutritional and economic valorization of the wild O. stricta for functional foods.

Asunto(s)

RESUMEN

The pressing need for highly efficient antibacterial strategies arises from the prevalence of microbial biofilm infections and the emergence of rapidly evolving antibiotic-resistant strains of pathogenic bacteria. Photodynamic therapy represents a highly efficient and compelling antibacterial approach, offering promising prospects for effective control of the development of bacterial resistance. However, the effectiveness of many photosensitizers is limited due to the reduced generation of reactive oxygen species (ROS) in hypoxic microenvironment, which commonly occur in pathological conditions such as inflammatory and bacteria-infected wounds. Herein, we designed and prepared two phenothiazine-derived photosensitizers (NB-1 and NB-2), which can effectively generate superoxide anion radicals (O2●-) through the type I process. Both photosensitizers demonstrate significant efficacy in vitro for the eradication of broad-spectrum bacteria. Moreover, NB-2 possesses distinct advantages including strong membrane binding and strong generation of O2●-, rendering it an exceptionally efficient antibacterial agent against mature biofilms. In addition, laser activated NB-2 could be applied to treat MRSA-infected wound in vivo, which offers new opportunities for potential practical applications.

Asunto(s)

RESUMEN

Reactive oxygen species (ROS) are produced by energy transfer and electron transport in plant chloroplast thylakoids at non-toxic levels under normal growth conditions, but at threatening levels under adverse or fluctuating environmental conditions. Among chloroplast ROS, singlet oxygen and superoxide anion radical, respectively, produced by photosystem II (PSII) and PSI, are known to be the major ROS under several stress conditions. Both are very unlikely to diffuse out of chloroplasts, but they are instead capable of triggering ROS-mediated chloroplast operational retrograde signalling to activate defence gene expression in concert with hormones and other molecular compounds. Therefore, their detection, identification and localization in vivo or in biological preparations is a priority for a deeper understanding of their role in (concurrent) regulation of plant growth and defence responses. Here, we present two EPR spin traps, abbreviated as TEMPD-HCl and DEPMPO, to detect and identify ROS in complex systems, such as isolated thylakoids, together with some hints and cautions to perform reliable spin trapping experiments.

Asunto(s)

RESUMEN

Cyanobacteria are among the oldest organisms colonizing Earth. Their great biodiversity and ability to biosynthesize secondary metabolites through a variety of routes makes them attractive resources for biotechnological applications and drug discovery. In this pioneer study, four filamentous cyanobacteria (Cephalothrix lacustris LEGE 15493, Leptolyngbya boryana LEGE 15486, Nodosilinea nodulosa LEGE 06104 and Leptothoe sp. LEGE 11479) were explored for their anti-inflammatory potential in cell and cell-free in vitro bioassays, involving different inflammatory mediators and enzymes. Extracts of different polarities were sequentially prepared and chemically characterized for their content of phycobiliproteins (PBPs) and carotenoids. HPLC-PDA analysis of the acetone extracts revealed ß-carotene to be the dominant carotenoid (18.4-44.3 mg/g) and zeaxanthin as the dominant xanthophyll (52.7-192.9 mg/g), with Leptothoe sp. LEGE 11479 and Nodosilinea nodulosa LEGE 06104, respectively, being the richest strains. The PBP profile was in accordance with the color presented by the aqueous extracts, with Leptolyngbya boryana LEGE 15486 being the richest in phycocyanin (204.5 µg/mg) and Leptothoe sp. LEGE 11479 the richest in phycoerythrin (78.5 µg/mg). Aqueous extracts were more effective in superoxide anion radical scavenging, while acetone ones were more effective in scavenging nitric oxide radical (●NO) and in inhibiting lipoxygenase. Acetone extracts also reduced ●NO production in lipopolysaccharide-stimulated RAW 264.7 macrophages, with the mechanistic study suggesting a downregulation of the inducible nitric oxide synthase expression. Nodosilinea nodulosa LEGE 06104 and Leptothoe sp. LEGE 11479 acetone extracts presented the lowest IC50 values for the mentioned assays, pointing them out as promising resources for the development of new multi-target anti-inflammatory therapies.

Asunto(s)

RESUMEN

Nanoplastics (NPs) is a novel plastic contaminant that could be taken up by cells and lead to severe biotoxicity toxicity, NPs in cells can cause oxidant damage by inducing reactive oxygen species (ROS) production and lead to acute inflammation. As a major ROS which related to many kinds of physiological and pathological processes, superoxide anion radical (O2•-) could be utilized as a signal of oxidant damage effected by NPs exposure in vivo. To detect the toxic damage mechanism of NPs, a fluorescence probe Bcy-OTf has been developed to monitor O2•- fluctuations content in cells and aquatic organisms after exposure to NPs. The probe has a high sensitivity (LOD = 20 nM) and a rapid responsive time (within 6 min), and it has high selectivity and low cytotoxicity to analysis the levels of the endogenous O2•-. Endogenous O2•- induced by NPs in living cells, Daphnia magna and larval zebrafish were analyzed. Moreover, the results confirmed the key role of MAPK and NF-κB pathway in NPs stimulation mechanisms in cells. This study indicated that Bcy-OTf can precisely assess the fluctuations of endogenous O2•-, which has potential for applying in further analysis mechanisms of NPs biological risks.

Asunto(s)

RESUMEN

Lactic acid bacteria (LAB) produce important metabolites during fermentation processes, such as exopolysaccharides (EPS), which represent powerful natural antioxidants. On the other hand, H. sabdariffa L. anthocyanin extracts protect LAB and support their development. This study uncovers for the first time, the antioxidant profile of Weissella confusa PP29 probiotic media and focuses on elevating its impressive antioxidant attributes by synergistically integrating H. sabdariffa L. anthocyanin extract. The multifaceted potential of this innovative approach is explored and the results are remarkable, allowing us to understand the protective capacity of the fermented product on the intestinal mucosa. The total phenolic content was much lower at the end of the fermentation process compared to the initial amount, confirming their LAB processing. The DPPH radical scavenging and FRAP of the fermented products were higher compared to ascorbic acid and antioxidant extracts, while superoxide anion radical scavenging and lipid peroxidation inhibitory activity were comparable to that of ascorbic acid. The antioxidant properties of the fermented products were correlated with the initial inoculum and anthocyanin concentrations. All these properties were preserved for 6 months, demonstrating the promising efficacy of this enriched medium, underlining its potential as a complex functional food with enhanced health benefits.

RESUMEN

Cyanobacteria have been recognized for their advantageous impact on plant growth and development. The application of certain techniques has the potential to enhance various aspects of plant development, including growth, yield, proximate content (such as protein and carbohydrate levels), as well as the ability to withstand abiotic stresses such as herbicide exposure. The current investigation focused on examining the influence of bioactive compounds derived from the cyanobacterium Neowestiellopsis persica strain A1387 on enhancing the antioxidant and anyimicrobial activity of wheat plants in their defense against the plant pathogenic Sunn pest. The findings of the study indicate that the levels of H2O2 and GPx in wheat plants that were infected with aphids were significantly elevated compared to the treatments where aphids and cyanobacteria extract were present. The confirmation of these results was achieved through the utilization of confocal and fluorescent microscope tests, respectively. Furthermore, the findings indicated that the constituents of the cyanobacterial extract augmented the plant's capacity to withstand stress by enhancing its defense mechanisms. In a broader context, the utilization of cyanobacterial extract demonstrated the ability to regulate the generation and impact of oxygen (O2) and hydrogen peroxide (H2O2), while concurrently enhancing the functionality of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) enzymes within wheat plants. This facilitation enabled the plants to effectively manage oxidative stress. Moreover, the findings of the antibacterial activity assessment conducted on the extract derived from cyanobacteria demonstrated notable susceptibility. The bacteria that exhibited the highest sensitivity to the extract of cyanobacterium Neowestiellopsis persica strain A1387 were staphylococcus aureus and pseudomonas aeruginosa. Conversely, salmonella typhi demonstrated the greatest resistance to the aforementioned extract. The potential impact of cyanobacteria extract on the antioxidative response of wheat plants to sunn pest infestation represents a novel contribution to the existing body of knowledge on the interaction between wheat plants and aphids.

Asunto(s)

RESUMEN

To examine the effects of membrane charge, the electrolyte species and glycosyl on the distribution of negatively charged radical of superoxide anion (·O2-) around the cell membrane, different phospholipid bilayer systems containing ·O2- radicals, different electrolytes and phospholipid bilayers were constructed through Charmm-GUI and Amber16. These systems were equilibrated with molecular dynamics by using Gromacs 5.0.2 to analyze the statistical behaviors of ·O2- near the lipid membrane under different conditions. It was found that in the presence of potassium rather than sodium, the negative charge of the phospholipid membrane is more likely to rarefy the superoxide anion distribution near the membrane surface. Further, the presence of glycosyl significantly reduced the density of ·O2- near the phospholipid bilayer by 78.3% compared with that of the neutral lipid membrane, which may have a significant contribution to reducing the lipid peroxidation from decreasing the ·O2- density near the membrane.

Asunto(s)

RESUMEN

Oxidative stress in soybean seedlings and the length of the soybean stem lesions infected with the fungus Macrophomina phaseolina (Tassi) Goid were evaluated to determine the most tolerant soybean cultivar to this pathogen. The level of superoxide anion radical (O2•-) production, the activity of the antioxidant enzyme superoxide-dismutase (SOD), and the intensity of lipid peroxidation (LP) were measured in four soybean cultivars: Favorit, Atlas, Victoria, and Rubin. Results showed that O2•- radical production and SOD activity were the most elevated in the cv. Favorit inoculated with M. phaseolina, while the level of lipid peroxidation intensity was the lowest compared to the control. This indicates that the soybean cv. Favorit has managed to prevent infection with M. phaseolina. Furthermore, higher O2•- radical production and lower SOD enzyme activity were measured in cv. Victoria, with enhanced lipid peroxidation. This means that the cv. Victoria was infected with M. phaseolina, and was the most sensitive. None of the tested oxidative stress parameters showed a significant difference in the cvs. Atlas and Rubin compared to the control. Furthermore, the highest lesion length was measured in the cv. Victoria, followed by cv. Favorit, while the lowest lesion length was measured in the cv. Atlas followed by the cv. Rubin; and thus, the cv. Atlas followed by the cv. Rubin, were the most tolerant soybean cultivars to this pathogen.

RESUMEN

Reactive oxygen species (ROS) play an essential role as both signaling molecule and damage agent during salt stress. As a signaling molecule, proper accumulation of H2O2 is crucial to trigger stress response and enhance stress tolerance. However, the dynamic regulation mechanism of H2O2 remains unclear. Here, we show that MhCAT2 (catalase 2 in Malus hupehensis) undergoes oxidative modification in an O2•--dependent manner and that oxidation at His225 residue reduces the MhCAT2 activity. Furthermore, the substitution of His225 with Tyr weakens the activity of MhCAT2. The oxidation modification provides a post-translational brake mechanism for the excessive scavenging of H2O2 caused by salt stress-induced catalase (CAT) over-expression. Overall, this finding provides mechanistic insights on stress tolerance augmentation by an O2•--mediated switch that regulates H2O2 homeostasis in Malus hupehensis.

Asunto(s)

RESUMEN

Tattooing on different parts of the body is a very common fashion trend in all sections of society globally. Skin allergies and other related skin diseases are very common among tattoo users. Benzo[ghi]perylene (BP) is a PAH and an important component of tattoo ink that showed prominent absorption under ultraviolet radiation (UVR) region. Therefore, to provide safety to the skin, a thorough safety study of BP exposed under UVR and Sunlight is very essential to understand their hazardous impact on the skin. BP showed a strong absorption of UVA and UVB radiation of sunlight. It is photolabile and degraded under UVA, UVB, and Sunlight in progressing order of time (1-4 h) without generating any novel photoproducts. Further, BP showed a specific generation of O2.- and OH radicals via activation of type I photodynamic reaction under exposure to UVA, UVB and Sunlight. Photocytotoxicity results illustrated concentration-dependent cell viability reduction in all exposure conditions of UVA, UVB, and Sunlight, respectively. Fluorescent probes (2',7'-dichlorofluorescein diacetate and dihydroethidium) for intracellular reactive oxygen species (ROS) generation supported the involvement of ROS in the phototoxicity of BP in the HaCaT cell line. Hoechst staining showed significant genomic insult induced by BP under UVA and UVB. Photoexcited BP promoted cell cycle arrest in the G1 phase and induced apoptosis confirmed via acridine orange/ethidium bromide staining. The findings of gene expression also supported apoptotic cell death in photoexcited BP via an increase in the level of pro-apoptotic gene (Bax) and a decrease in the level of anti-apoptotic gene (Bcl-2). The aforementioned finding indicates that tattoo users should avoid using BP since it can cause skin damage/diseases if they are exposed to UVR or Sunlight while tattooing on the body.

Asunto(s)

RESUMEN

Biochar activated peroxymonosulfate has been widely used to degrade organic pollutants. However, the chemical inertness of the sp2 hybrid conjugated carbon framework and the limited number of active sites on the pristine biochar resulted in the low catalytic activity of the system, restricting its further application. In this study, nitrogen-doped biochar was prepared following a simple one-step synthesis method taking advantage of the similar atomic radius and significant difference in electronegativity of N and C atoms to explore the properties and mechanisms of biochar-mediated peroxymonosulfate activation to degrade 2,4-dichlorophenol. Results from degradation experiments revealed that the catalytic efficiency of the prepared nitrogen-doped biochar was approximately 37.8 times higher than that of the undoped biochar. Quenching experiments combined with Electron paramagnetic resonance (EPR) analysis illustrated that the generated singlet oxygen (1O2) and superoxide anion radical (O2•-) were the main reactive oxidative species that dominated the target organics removal processes. This work will provide a theoretical basis for expanding the practical application of nitrogen-doped biochar to remediate water pollution via peroxymonosulfate activation.

Asunto(s)

RESUMEN

Oxidative stress is an important pathophysiological mechanism in the development of numerous cardiovascular disorders, but few studies have examined the levels of oxidative stress in adults with congenital heart disease (CHD). The objective of this study was to investigate oxidative stress levels in adults with CHD and the association with inflammation, exercise capacity and endothelial function. To this end, 36 adults with different types of CHD and 36 age- and gender-matched healthy controls were enrolled. Blood cell counts, hs-CRP, NT-proBNP, fasting glucose, cholesterol levels, iron saturation and folic acid concentrations were determined in venous blood samples. Levels of superoxide anion radical in whole blood were determined using electron paramagnetic resonance spectroscopy in combination with the spin probe CMH. Physical activity was assessed with the IPAQ-SF questionnaire. Vascular function assessment (EndoPAT) and cardiopulmonary exercise testing were performed in the patient group. Superoxide anion radical levels were not statistically significantly different between adults with CHD and the matched controls. Moreover, oxidative stress did not correlate with inflammation, or with endothelial function or cardiorespiratory fitness in CHD; however, a significant negative correlation with iron saturation was observed. Overall, whole blood superoxide anion radical levels in adults with CHD were not elevated, but iron levels seem to play a more important role in oxidative stress mechanisms in CHD than in healthy controls. More research will be needed to improve our understanding of the underlying pathophysiology of CHD.

RESUMEN

This paper describes the gangliopexy method, a method for creating a new center of local neurohumoral regulation, based on the formation of new connections discovered between the nervous system and the vascular system. The prospects for the development of this method are studied. At the same time, novel concepts about the cycles of nitric oxide and the superoxide anion radical are introduced. A possible role of these cycles is examined in the protection of cells and the body as a whole against oxidative and nitrosative stress, which develops when (in 5-30% of cases) destructive changes in the displaced ganglion lead to vascular complications and an increased risk of mortality. Mechanisms that can protect nerve cells, prevent the development of destructive changes in these cells and reduce the risk of mortality are also investigated.

RESUMEN

Hypertensive cardiovascular disease is a persistent threat to public health. Elucidating the pathogenesis of hypertension is expected to provide more highly targeted therapies for patients. To date, reactive oxygen species (ROS) induced endothelial nitric oxide synthase (eNOS) uncoupling are generally considered to be common phenomena in hypertension. However, the critical factor contribute to persistent eNOS uncoupling remains poorly understood. Herein, we established a fluorescence probe, GolROS, for the multicolored and simultaneous detection of Golgi O2•- and H2O2 in situ. We successfully detected increases in Golgi ROS levels in hypertensive mice and evaluated the pharmaceutical effects of various antihypertensive drugs. More importantly, we identified the ROS post-transcriptional modification sites on dihydrofolate reductase (DHFR). Altogether, we propose a novel therapeutic target for hypertension, which will promote the development of new antihypertensive drugs, and also developed an ideal fluorescence probe to study in situ Golgi O2•- and H2O2 changes in various biochemical processes.

Asunto(s)

RESUMEN

Light capture by chlorophylls and photosynthetic electron transport bury the risk of the generation of reactive oxygen species (ROS) including singlet oxygen, superoxide anion radicals and hydrogen peroxide. Rapid changes in light intensity, electron fluxes and accumulation of strong oxidants and reductants increase ROS production. Superoxide is mainly generated at the level of photosystem I while photosystem II is the main source of singlet oxygen. ROS can induce oxidative damage of the photosynthetic apparatus, however, ROS are also important to tune processes inside the chloroplast and participate in retrograde signalling regulating the expression of genes involved in acclimation responses. Under most physiological conditions light harvesting and photosynthetic electron transport are regulated to keep the level of ROS at a non-destructive level. Photosystem II is most prone to photoinhibition but can be quickly repaired while photosystem I is protected in most cases. The size of the transmembrane proton gradient is central for the onset of mechanisms that protect against photoinhibition. The proton gradient allows dissipation of excess energy as heat in the antenna systems and it regulates electron transport. pH-dependent slowing down of electron donation to photosystem I protects it against ROS generation and damage. Cyclic electron transfer and photoreduction of oxygen contribute to the size of the proton gradient. The yield of singlet oxygen production in photosystem II is regulated by changes in the midpoint potential of its primary quinone acceptor. In addition, numerous antioxidants inside the photosystems, the antenna and the thylakoid membrane quench or scavenge ROS.

Asunto(s)

RESUMEN

Antibiotics are widely supplied over all the world to animals and humans to fight and heal bacteriological diseases. The uptake of antibiotics has largely increased the average-life expectancy of living beings. However, these recalcitrant products have been detected at low concentrations in natural waters, with potential health risks due to alterations in food chains and an increase in the resistance to bacterial infection, control of infectious diseases, and damage of the beneficial bacteria. The high stability of antibiotics at mild conditions prevents their effective removal in conventional wastewater treatment plants. A powerful advanced oxidation processes such as the electro-Fenton (EF) process is being developed as a guarantee for their destruction by •OH generated as strong oxidant. This review presents a critical, exhaustive, and detailed analysis on the application of EF to remediate synthetic and real wastewaters contaminated with common antibiotics, covering the period 2017-2021. Homogeneous EF and heterogeneous EF involving iron solid catalysts or iron functionalized cathodes, as well as their hybrid and sequential treatments, are exhaustively examined. Their fundamentals and characteristics are detailed, and the main results obtained for the removal of the most used antibiotic families are carefully described and discussed. The role of generated oxidizing agents is explained, and the by-products generated, and reaction sequences proposed are detailed.

Asunto(s)

RESUMEN

Mitochondria actively participate in oxygenic metabolism and are one of the major sources of reactive oxygen species (ROS) production in plant cells. However, instead of measuring ROS concentrations in organelles it is more worthwhile to observe active ROS generation or downstream oxidation products, because the steady state level of ROS is easily buffered. Here, we describe how to measure the in vitro production of superoxide anion radicals (O2·-) by mitochondria and the release of O2·- into the cytosol. A method to determine glutathione, which is the most abundant mitochondrial low-mass antioxidant, is presented since changes in the redox state of glutathione can be indicative of the oxidative action of ROS. The identification of oxidative damage to mitochondrial components is the ultimate symptom that ROS homeostasis is not under control. We present how to determine the extent of oxidation of membrane lipids and the carbonylation of mitochondrial proteins. In summary, oxidative stress symptoms have to be analyzed at different levels, including ROS production, scavenging capacity, and signs of destruction, which only together can be considered markers of mitochondrial ROS status.

Asunto(s)