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1.
Proc Natl Acad Sci U S A ; 121(30): e2401452121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39018193

RESUMO

Nitrophenols present on the surface of particulates are ubiquitous in the atmosphere. However, its atmospheric photochemical transformation pathway remains unknown, for which the crucial effect of visible light is largely overlooked, resulting in an incomplete understanding of the effects of nitrophenols in the atmospheric environment. This study delves into the photolysis mechanism of 4-nitrophenol (4NP), one of the most abundant atmospheric nitrophenol compounds, on the surface of photoactive particulates under visible light irradiation. Unexpectedly, the nonradical species (singlet oxygen, 1O2) was identified as a dominant factor in driving the visible photolysis of 4NP. The pathways of HONO and p-benzoquinone (C6H4O2) generation were clarified by acquiring direct evidence of C-N and O-H bond breakage in the nitro (-NO2) and hydroxyl (-OH) groups of 4NP. The further decomposition of HONO results in the generation of NO and hydroxyl radicals, which could directly contribute to atmospheric oxidizing capacity and complicate the PM2.5 composition. Significantly, the behavior of 1O2-induced visible photolysis of 4NP was universal on the surface of common particulates in the atmosphere, such as A1 dust and Fe2O3. This work advances the understanding of the photochemical transformation mechanism of particulate-phase atmospheric nitrophenols, which is indispensable in elucidating the role of nitrophenols in atmospheric chemistry.

2.
Nano Lett ; 24(6): 2071-2080, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38305186

RESUMO

Ferroptosis is a novel type of nonapoptotic programmed cell death involving the accumulation of lipid peroxidation (LPO) to a lethal threshold. Herein, we propose tunable zeolitic imidazolate framework (ZIFs)-engineered biodegradable nanozymes for ferroptosis mediated by both reactive oxygen species (ROS) and nitrogen species (RNS). l-Arginine is utilized as an exogenous nitric oxide donor and loaded into hollow ZIFs@MnO2 artificial nanozymes, which are formed by etching ZIFs with potassium permanganate and simultaneously generating a MnO2 shell in situ. The constructed nanozymes with multienzyme-like activities including peroxidase, oxidase, and catalase can release satisfactory ROS and RNS through a cascade reaction, consequently promoting the accumulation of LPO. Furthermore, it can improve the efficiency of ferroptosis through a three-step strategy of glutathione (GSH) depletion; that is, the outer MnO2 layer consumes GSH under slightly acidic conditions and RNS downregulates SLC7A11 and glutathione reductase, thus directly inhibiting GSH biosynthesis and indirectly preventing GSH regeneration.


Assuntos
Ferroptose , Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Compostos de Manganês/farmacologia , Óxidos , Estresse Oxidativo , Glutationa
3.
Cell Immunol ; 399-400: 104811, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38518686

RESUMO

Helicobacter pylori-associated stomach infection is a leading cause of gastric ulcer and related cancer. H. pylori modulates the functions of infiltrated immune cells to survive the killing by reactive oxygen and nitrogen species (ROS and RNS) produced by these cells. Uncontrolled immune responses further produce excess ROS and RNS which lead to mucosal damage. The persistent oxidative stress is a major cause of gastric cancer. H. pylori regulates nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs), nitric oxide synthase 2 (NOS2), and polyamines to control ROS and RNS release through lesser-known mechanisms. ROS and RNS produced by these pathways differentiate macrophages and T cells from protective to inflammatory phenotype. Pathogens-associated molecular patterns (PAMPs) induced ROS activates nuclear oligomerization domain (NOD), leucine rich repeats (LRR) and pyrin domain-containing protein 3 (NLRP3) inflammasome for the release of pro-inflammatory cytokines. This study evaluates the role of H. pylori secreted concentrated proteins (HPSCP) related oxidative stress role in NLRP3 inflammasome activation and macrophage differentiation. To perceive the role of ROS/RNS, THP-1 and AGS cells were treated with 10 µM diphenyleneiodonium (DPI), 50 µM salicyl hydroxamic acid (SHX), 5 µM Carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone (FCCP), which are specific inhibitors of NADPH oxidase (NOX), Myeloperoxidase (MPO), and mitochondrial oxidative phosphorylation respectively. Cells were also treated with 10 µM of NOS2 inhibitor l-NMMA and 10 µM of N-acetyl cysteine (NAC), a free radical scavenger·H2O2 (100 µM) treated and untreated cells were used as positive controls and negative control respectively. The expression of gp91phox (NOX2), NOS2, NLRP3, CD86 and CD163 was analyzed through fluorescent microscopy. THP-1 macrophages growth was unaffected whereas the gastric epithelial AGS cells proliferated in response to higher concentration of HPSCP. ROS and myeloperoxidase (MPO) level increased in THP-1 cells and nitric oxide (NO) and lipid peroxidation significantly decreased in AGS cells. gp91phox expression was unchanged, whereas NOS2 and NLRP3 downregulated in response to HPSCP, but increased after inhibition of NO, ROS and MPO in THP-1 cells. HPSCP upregulated the expression of M1 and M2 macrophage markers, CD86 and CD163 respectively, which was decreased after the inhibition of ROS. This study concludes that there are multiple pathways which are generating ROS during H. pylori infection which further regulates other cellular processes. NO is closely associated with MPO and inhibition of NLRP3 inflammasome. The low levels of NO and MPO regulates gastrointestinal tract homeostasis and overcomes the inflammatory response of NLRP3. The ROS also plays crucial role in macrophage polarization hence alter the immune responses duing H. pylori pathogenesis.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Inflamassomos , Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Oxidativo , Espécies Reativas de Oxigênio , Humanos , Helicobacter pylori/imunologia , Espécies Reativas de Oxigênio/metabolismo , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/metabolismo , Inflamassomos/metabolismo , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Proteínas de Bactérias/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Células THP-1 , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Diferenciação Celular/imunologia
4.
Am J Physiol Regul Integr Comp Physiol ; 326(6): R552-R566, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38586887

RESUMO

Nitric oxide is produced at low micromolar levels following the induction of inducible nitric oxide synthase (iNOS) and is responsible for mediating the inhibitory actions of cytokines on glucose-stimulated insulin secretion by islets of Langerhans. It is through the inhibition of mitochondrial oxidative metabolism, specifically aconitase and complex 4 of the electron transport chain, that nitric oxide inhibits insulin secretion. Nitric oxide also attenuates protein synthesis, induces DNA damage, activates DNA repair pathways, and stimulates stress responses (unfolded protein and heat shock) in ß-cells. In this report, the time- and concentration-dependent effects of nitric oxide on the expression of six genes known to participate in the response of ß-cells to this free radical were examined. The genes included Gadd45α (DNA repair), Puma (apoptosis), Hmox1 (antioxidant defense), Hsp70 (heat shock), Chop (UPR), and Ppargc1α (mitochondrial biogenesis). We show that nitric oxide stimulates ß-cell gene expression in a narrow concentration range of ∼0.5-1 µM or levels corresponding to iNOS-derived nitric oxide. At concentrations greater than 1 µM, nitric oxide fails to stimulate gene expression in ß-cells, and this is associated with the inhibition of mitochondrial oxidative metabolism. This narrow concentration range of responses is ß-cell selective, as the actions of nitric oxide in non-ß-cells (α-cells, mouse embryonic fibroblasts, and macrophages) are concentration dependent. Our findings suggest that ß-cells respond to a narrow concentration range of nitric oxide that is consistent with the levels produced following iNOS induction, and that these concentration-dependent actions are selective for insulin-containing cells.


Assuntos
Proteínas Reguladoras de Apoptose , Regulação da Expressão Gênica , Células Secretoras de Insulina , Óxido Nítrico Sintase Tipo II , Óxido Nítrico , Animais , Óxido Nítrico/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição CHOP/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP70/genética , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase (Desciclizante)/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Insulina/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Ratos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas de Membrana , Heme Oxigenase-1
5.
New Phytol ; 244(3): 786-797, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39223868

RESUMO

Plant survival to a potential plethora of diverse environmental insults is underpinned by coordinated communication amongst organs to help shape effective responses to these environmental challenges at the whole plant level. This interorgan communication is supported by a complex signal network that regulates growth, development and environmental responses. Nitric oxide (NO) has emerged as a key signalling molecule in plants. However, its potential role in interorgan communication has only recently started to come into view. Direct and indirect evidence has emerged supporting that NO and related species (S-nitrosoglutathione, nitro-linolenic acid) are mobile interorgan signals transmitting responses to stresses such as hypoxia and heat. Beyond their role as mobile signals, NO and related species are involved in mediating xylem development, thus contributing to efficient root-shoot communication. Moreover, NO and related species are regulators in intraorgan systemic defence responses aiming an effective, coordinated defence against pathogens. Beyond its in planta signalling role, NO and related species may act as ex planta signals coordinating external leaf-to-leaf, root-to-leaf but also plant-to-plant communication. Here, we discuss these exciting developments and emphasise how their manipulation may provide novel strategies for crop improvement.


Assuntos
Óxido Nítrico , Óxido Nítrico/metabolismo , Transdução de Sinais , Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Xilema/metabolismo , Xilema/fisiologia
6.
Environ Sci Technol ; 58(39): 17510-17519, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39297779

RESUMO

The application of 222 nm far-UVC irradiation for degrading organic micropollutants in water shows promise. Nitrate (NO3-), found in nearly all water bodies, can significantly impact the performance of 222 nm far-UVC-driven systems. This work was the first to investigate the effect of NO3- on sulfamethoxazole (SMX) photodegradation at 222 nm, finding that NO3- significantly enhances SMX degradation in different dissociated forms. Besides the hydroxyl radical (•OH), reactive nitrogen species (RNS) also played important roles in SMX degradation. With increasing NO3- concentration, the RNS contribution to SMX degradation decreased from 25.7 to 8.6% at pH 3 but increased from 1.5 to 24.7% at pH 7, since the deprotonated SMX with electron-rich groups reacted more easily with RNS. The transformation mechanisms of SMX involving isomerization, bond cleavage, hydroxylation, nitrosation, and nitration processes were proposed. 15N isotope labeling experiments showed that the RNS-induced nitrated products even became the major products of SMX in the 222 nm far-UVC/NO3- system at pH 7 and exhibited a higher toxicity than SMX itself. Further research is necessary to avoid or eliminate these toxic byproducts. This study provides valuable insights for guiding the utilization of 222 nm far-UVC for treating antibiotics in NO3--containing water.


Assuntos
Nitratos , Espécies Reativas de Nitrogênio , Sulfametoxazol , Sulfametoxazol/química , Nitratos/química , Espécies Reativas de Nitrogênio/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Fotólise
7.
Environ Sci Technol ; 58(36): 16087-16099, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39205652

RESUMO

This study aims to fine-tune the plasma composition with a particular emphasis on reactive nitrogen species (RNS) including nitrogen dioxide (NO2), dinitrogen pentoxide (N2O5), and nitrous oxide (N2O), produced by a self-constructed cylindrical dielectric barrier discharge (CDBD). We demonstrated the effective manipulation of the plasma chemical profile by optimizing electrical properties, including the applied voltage and frequency, and by adjusting the nitrogen and oxygen ratios in the gas mixture. Additionally, quantification of these active species was achieved using Fourier transform infrared spectroscopy. The study further extends to exploring the aerosol polymerization of acrylamide (AM) into polyacrylamide (PAM), serving as a model reaction to evaluate the reactivity of different plasma-generated species, highlighting the significant role of NO2 in achieving high polymerization yields. Complementing our experimental data, molecular dynamics (MD) simulations, based on the ReaxFF reactive force field potential, explored the interactions between reactive oxygen species, specifically hydroxyl radicals (OH) and hydrogen peroxide (H2O2), with water molecules. Understanding these interactions, combined with the optimization of plasma chemistry, is crucial for enhancing the effectiveness of DBD plasma in environmental applications like air purification and water treatment.


Assuntos
Simulação de Dinâmica Molecular , Óxido Nitroso , Espécies Reativas de Nitrogênio , Espécies Reativas de Nitrogênio/química , Óxido Nitroso/química , Gases em Plasma/química , Dióxido de Nitrogênio/química , Peróxido de Hidrogênio/química
8.
Plant Cell Rep ; 43(7): 185, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951279

RESUMO

The Oryza genus, containing Oryza sativa L., is quintessential to sustain global food security. This genus has a lot of sophisticated molecular mechanisms to cope with environmental stress, particularly during vulnerable stages like flowering. Recent studies have found key involvements and genetic modifications that increase resilience to stress, including exogenous application of melatonin, allantoin, and trehalose as well as OsSAPK3 and OsAAI1 in the genetic realm. Due to climate change and anthropogenic reasons, there is a rise in sea level which raises a concern of salinity stress. It is tackled through osmotic adjustment and ion homeostasis, mediated by genes like P5CS, P5CR, GSH1, GSH2, and SPS, and ion transporters like NHX, NKT, and SKC, respectively. Oxidative damage is reduced by a complex action of antioxidants, scavenging RONS. A complex action of genes mediates cold stress with studies highlighting the roles of OsWRKY71, microRNA2871b, OsDOF1, and OsICE1. There is a need to research the mechanism of action of proteins like OsRbohA in ROS control and the action of regulatory genes in stress response. This is highly relevant due to the changing climate which will raise a lot of environmental changes that will adversely affect production and global food security if certain countermeasures are not taken. Overall, this study aims to unravel the molecular intricacies of ROS and RNS signaling networks in Oryza plants under stress conditions, with the ultimate goal of informing strategies for enhancing stress tolerance and crop performance in this important agricultural genus.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Transdução de Sinais , Estresse Fisiológico , Oryza/genética , Oryza/metabolismo , Oryza/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Espécies Reativas de Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
9.
Plant Cell Rep ; 43(8): 193, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008125

RESUMO

Soil salinity is a major constraint for sustainable agricultural productivity, which together with the incessant climate change may be transformed into a severe threat to the global food security. It is, therefore, a serious concern that needs to be addressed expeditiously. The overproduction and accumulation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are the key events occurring during salt stress, consequently employing nitro-oxidative stress and programmed cell death in plants. However, very sporadic studies have been performed concerning different aspects of nitro-oxidative stress in plants under salinity stress. The ability of plants to tolerate salinity is associated with their ability to maintain the cellular redox equilibrium mediated by both non-enzymatic and enzymatic antioxidant defense mechanisms. The present review emphasizes the mechanisms of ROS and RNS generation in plants, providing a detailed evaluation of how redox homeostasis is conserved through their effective removal. The uniqueness of this article stems from its incorporation of expression analyses of candidate genes for different antioxidant enzymes involved in ROS and RNS detoxification across various developmental stages and tissues of rice, utilizing publicly available microarray data. It underscores the utilization of modern biotechnological methods to improve salinity tolerance in crops, employing different antioxidants as markers. The review also explores how various transcription factors contribute to plants' ability to tolerate salinity by either activating or repressing the expression of stress-responsive genes. In summary, the review offers a thorough insight into the nitro-oxidative homeostasis strategy for extenuating salinity stress in plants.


Assuntos
Homeostase , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Tolerância ao Sal , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Tolerância ao Sal/genética , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Antioxidantes/metabolismo , Oxirredução , Plantas/metabolismo , Salinidade
10.
J Fish Dis ; 47(4): e13914, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38185743

RESUMO

Coccidiosis is an important disease in juvenile fish because of severe intestinal injury during infection. We first reported the mixed infection of intestinal coccidia and its association with health status and pathological findings in juvenile Asian seabass (Lates calcarifer) cultured in Thailand. Two groups of Asian seabass, 60-day fish and 90-day fish, were sampled to investigate prevalence and coccidian infection intensity using morphological characterization and PCR. Phylogenetic analysis of 18S rRNA gene amplified from the intestines revealed Eimeria sp. and Cryptosporidium sp. infection. The prevalence of Eimeria sp. and Cryptosporidium sp. in sampled fish was 100%. Clinical outcomes assessed, using health assessment index (HAI) scoring and semi-quantitative grading of intestinal lesions and inflammation, demonstrated that all fish developed variety of pathology and clinical illness; however, infection intensity in 60-day fish was significantly higher (p < .05) than 90-day fish. The HAI score of 60-day fish was poorer than 90-day fish, which correlated to a high infection intensity (r = .397), analysed by Pearson correlation coefficient. Overproduction of intestinal oxidants contributing to mucosal injury was examined by nitrotyrosine expression. The high production of reactive nitrogen species indicated severe inflammatory response, and intestinal injuries occurred mainly in the 60-day fish.


Assuntos
Criptosporidiose , Cryptosporidium , Eimeria , Doenças dos Peixes , Perciformes , Animais , Filogenia , Tailândia/epidemiologia , Cryptosporidium/genética , Doenças dos Peixes/epidemiologia , Peixes
11.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474253

RESUMO

The brain's unique characteristics make it exceptionally susceptible to oxidative stress, which arises from an imbalance between reactive oxygen species (ROS) production, reactive nitrogen species (RNS) production, and antioxidant defense mechanisms. This review explores the factors contributing to the brain's vascular tone's vulnerability in the presence of oxidative damage, which can be of clinical interest in critically ill patients or those presenting acute brain injuries. The brain's high metabolic rate and inefficient electron transport chain in mitochondria lead to significant ROS generation. Moreover, non-replicating neuronal cells and low repair capacity increase susceptibility to oxidative insult. ROS can influence cerebral vascular tone and permeability, potentially impacting cerebral autoregulation. Different ROS species, including superoxide and hydrogen peroxide, exhibit vasodilatory or vasoconstrictive effects on cerebral blood vessels. RNS, particularly NO and peroxynitrite, also exert vasoactive effects. This review further investigates the neuroprotective effects of antioxidants, including superoxide dismutase (SOD), vitamin C, vitamin E, and the glutathione redox system. Various studies suggest that these antioxidants could be used as adjunct therapies to protect the cerebral vascular tone under conditions of high oxidative stress. Nevertheless, more extensive research is required to comprehensively grasp the relationship between oxidative stress and cerebrovascular tone, and explore the potential benefits of antioxidants as adjunctive therapies in critical illnesses and acute brain injuries.


Assuntos
Lesões Encefálicas , Oxigênio , Humanos , Espécies Reativas de Oxigênio/metabolismo , Oxigênio/farmacologia , Nitrogênio/farmacologia , Estresse Oxidativo , Antioxidantes/farmacologia , Espécies Reativas de Nitrogênio/metabolismo , Niacinamida/farmacologia , Lesões Encefálicas/tratamento farmacológico
12.
Int J Mol Sci ; 25(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39125983

RESUMO

Reduction-oxidation (redox) chemistry plays a vital role in human homeostasis. These reactions play critical roles in energy generation, as part of innate immunity, and in the generation of secondary messengers with various functions such as cell cycle progression or the release of neurotransmitters. Despite this cornerstone role, if left unchecked, the body can overproduce reactive oxygen species (ROS) or reactive nitrogen species (RNS). When these overwhelm endogenous antioxidant systems, oxidative stress (OS) occurs. In neonates, OS has been associated with retinopathy of prematurity (ROP), leukomalacia, and bronchopulmonary dysplasia (BPD). Given its broad spectrum of effects, research has started to examine whether OS plays a role in necrotizing enterocolitis (NEC). In this paper, we will discuss the basics of redox chemistry and how the human body keeps these in check. We will then discuss what happens when these go awry, focusing mostly on NEC in neonates.


Assuntos
Enterocolite Necrosante , Oxirredução , Estresse Oxidativo , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Humanos , Enterocolite Necrosante/metabolismo , Enterocolite Necrosante/patologia , Espécies Reativas de Oxigênio/metabolismo , Recém-Nascido , Espécies Reativas de Nitrogênio/metabolismo , Antioxidantes/metabolismo , Animais
13.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474303

RESUMO

Underwater activities are characterized by an imbalance between reactive oxygen/nitrogen species (RONS) and antioxidant mechanisms, which can be associated with an inflammatory response, depending on O2 availability. This review explores the oxidative stress mechanisms and related inflammation status (Oxy-Inflammation) in underwater activities such as breath-hold (BH) diving, Self-Contained Underwater Breathing Apparatus (SCUBA) and Closed-Circuit Rebreather (CCR) diving, and saturation diving. Divers are exposed to hypoxic and hyperoxic conditions, amplified by environmental conditions, hyperbaric pressure, cold water, different types of breathing gases, and air/non-air mixtures. The "diving response", including physiological adaptation, cardiovascular stress, increased arterial blood pressure, peripheral vasoconstriction, altered blood gas values, and risk of bubble formation during decompression, are reported.


Assuntos
Mergulho , Oxigênio , Humanos , Mergulho/fisiologia , Nitrogênio , Hipóxia , Inflamação
14.
Int J Mol Sci ; 25(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39201563

RESUMO

Nitric oxide (NO) has been firmly established as a key signaling molecule in plants, playing a significant role in regulating growth, development and stress responses. Given the imperative of sustainable agriculture and the urgent need to meet the escalating global demand for food, it is imperative to safeguard crop plants from the effects of climate fluctuations. Plants respond to environmental challenges by producing redox molecules, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), which regulate cellular, physiological, and molecular processes. Nitric oxide (NO) plays a crucial role in plant stress tolerance, acting as a signaling molecule or free radical. NO is involved in various developmental processes in plants through diverse mechanisms. Exogenous NO supplementation can alleviate the toxicity of abiotic stresses and enhance plant resistance. In this review we summarize the studies regarding the production of NO in peroxisomes, and how its molecule and its derived products, (ONOO-) and S-nitrosoglutathione (GSNO) affect ROS metabolism in peroxisomes. Peroxisomal antioxidant enzymes including catalase (CAT), are key targets of NO-mediated post-translational modification (PTM) highlighting the dynamic metabolism of ROS and RNS in peroxisomes.


Assuntos
Óxido Nítrico , Peroxissomos , Processamento de Proteína Pós-Traducional , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Peroxissomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo
15.
Molecules ; 29(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611909

RESUMO

Dinitrosyl iron complexes (DNICs) stabilize nitric oxide in cells and tissues and constitute an important form of its storage and transportation. DNICs may comprise low-molecular-weight ligands, e.g., thiols, imidazole groups in chemical compounds with low molecular weight (LMWDNICs), or high-molecular-weight ligands, e.g., peptides or proteins (HMWDNICs). The aim of this study was to investigate the role of low- and high-molecular-weight ligands in DNIC formation. Lysosomal and proteasomal proteolysis was inhibited by specific inhibitors. Experiments were conducted on human erythroid K562 cells and on K562 cells overexpressing a heavy chain of ferritin. Cell cultures were treated with •NO donor. DNIC formation was monitored by electron paramagnetic resonance. Pretreatment of cells with proteolysis inhibitors diminished the intensity and changed the shape of the DNIC-specific EPR signal in a treatment time-dependent manner. The level of DNIC formation was significantly influenced by the presence of protein degradation products. Interestingly, formation of HMWDNICs depended on the availability of LMWDNICs. The extent of glutathione involvement in the in vivo formation of DNICs is minor yet noticeable, aligning with our prior research findings.


Assuntos
Óxido Nítrico , Óxidos de Nitrogênio , Humanos , Proteólise , Óxidos de Nitrogênio/farmacologia , Ferro
16.
J Sci Food Agric ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39268748

RESUMO

BACKGROUND: This study aimed to explore how interactions between reactive oxygen species (ROS) and reactive nitrogen species (RNS) affect oxidative properties, nitrosative properties, and myofibrillar protein degradation during postmortem aging of yak meat. RESULTS: Yak longissimus dorsi was incubated with saline, ROS activator (H2O2)/inhibitor N-Acetyl-L-cysteine (NAC) and RNS activator S-Nitrosoglutathione (GSNO)/inhibitor L-NAME hydrochloride (L-NAME) combined treatments at 4 °C for 12, 24, 72, 120, and 168 h. The results indicated that regardless of whether RNS was activated or inhibited, activated ROS played a dominant role in myofibrillar protein degradation by oxidative modification to increase carbonyl content, disulfide bonds, surface hydrophobicity, and dimerized tyrosine while decreasing sulfhydryl content, thereby degrading nebulin, titin, troponin-t and desmin. Notably, the Warner-Bratzler shear force (WBSF) of the H2O2 + L-NAME group was the smallest, whereas that of the NAC + GSNO group was smaller than that of the NAC + L-NAME group. CONCLUSION: These findings provide new insights into meat tenderization patterns through the interaction between ROS and RNS. © 2024 Society of Chemical Industry.

17.
Small ; 19(41): e2302331, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37246260

RESUMO

A therapeutic strategy that could address colitis of multiple etiologies while restoring the dysbiosis of gut microbiota is attractive. Here, Aurozyme, a novel nanomedicine comprised of gold nanoparticles (AuNPs) and glycyrrhizin (GL) with a glycol chitosan coating layer, as a promising approach for colitis, is demonstrated. The unique feature of Aurozyme is the conversion of harmful peroxidase-like activity of AuNPs to beneficial catalase-like activity due to the amine-rich environment provided by the glycol chitosan. This conversion process enables Aurozyme to oxidize the hydroxyl radicals derived from AuNP, producing water and oxygen molecules. In fact, Aurozyme effectively scavenges reactive oxygen/reactive nitrogen species (ROS/RNS) and damage-associated molecular patterns (DAMPs), which can attenuate the M1 polarization of macrophage. It exhibits prolonged adhesion to the lesion site, promoting sustained anti-inflammatory effects and restoring intestinal function in colitis-challenged mice. Additionally, it increases the abundance and diversity of beneficial probiotics, which are essential for maintaining microbial homeostasis in the gut. The work highlights the transformative potential of nanozymes for the comprehensive treatment of inflammatory disease and represents an innovative switching technology of enzyme-like activity by Aurozyme.


Assuntos
Colite , Nanopartículas Metálicas , Camundongos , Animais , Peroxidase , Catalase , Ouro , Colite/tratamento farmacológico , Antioxidantes , Espécies Reativas de Oxigênio , Oxigênio
18.
J Exp Bot ; 74(19): 5970-5988, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37668424

RESUMO

Deterioration and impoverishment of soil, caused by environmental pollution and climate change, result in reduced crop productivity. To adapt to hostile soils, plants have developed a complex network of factors involved in stress sensing, signal transduction, and adaptive responses. The chemical properties of reactive oxygen species (ROS) and reactive nitrogen species (RNS) allow them to participate in integrating the perception of external signals by fine-tuning protein redox regulation and signal transduction, triggering specific gene expression. Here, we update and summarize progress in understanding the mechanistic basis of ROS and RNS production at the subcellular level in plants and their role in the regulation of ion channels/transporters at both transcriptional and post-translational levels. We have also carried out an in silico analysis of different redox-dependent modifications of ion channels/transporters and identified cysteine and tyrosine targets of nitric oxide in metal transporters. Further, we summarize possible ROS- and RNS-dependent sensors involved in metal stress sensing, such as kinases and phosphatases, as well as some ROS/RNS-regulated transcription factors that could be involved in metal homeostasis. Understanding ROS- and RNS-dependent signaling events is crucial to designing new strategies to fortify crops and improve plant tolerance of nutritional imbalance and metal toxicity.


Assuntos
Óxido Nítrico , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo , Oxirredução , Metais/metabolismo , Canais Iônicos/metabolismo
19.
Int Arch Allergy Immunol ; 184(12): 1184-1197, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37703833

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Microbial infection, immune system dysfunction, and skin barrier defunctionalization have been regarded as the central events in AD pathogenesis. Cold atmospheric plasma (CAP) is an unbound system composed of many free electrons, ions, and neutral particles, with macroscopic time and spatial scales. Based on dielectric barrier discharge, glow discharge, corona discharge, or arch discharge, CAP is generated at normal atmospheric pressure. Its special physical properties maintain its temperature at 20°C-40°C, combining the advantages of high safety and strong ionic activity. CAP has been tentatively used in inflammatory or pruritic skin disorders such as psoriasis, pruritus, and ichthyosis. Increasing data suggest that CAP can attack the microbial structure due to its unique effects, such as heat, ultraviolet radiation, and free radicals, resulting in its inactivation. Meanwhile, CAP regulates reactive oxygen species and reactive nitrogen species in and out of the cells, thereby improving cell immunocompetence. In addition, CAP has a beneficial effect on the skin barrier function via changing the skin lipid contents and increasing the skin permeability to drugs. This review summarizes the potential effects of CAP on the major pathogenic causes of AD and discusses the safety of CAP application in dermatology in order to expand the clinical application value of CAP to AD.


Assuntos
Dermatite Atópica , Gases em Plasma , Dermatopatias , Humanos , Dermatite Atópica/terapia , Gases em Plasma/uso terapêutico , Gases em Plasma/química , Raios Ultravioleta , Pele
20.
Cell Biol Int ; 47(2): 327-340, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36342241

RESUMO

The serious problems of conventional breast cancer therapy strategies such as drug resistance, severe side effects, and lack of selectivity prompted the development of various cold atmospheric plasma (CAP) devices. Due to its advanced technology, CAP can produce a unique environment rich in reactive oxygen and nitrogen species (RONS), photons, charged ions, and an electric field, making it a promising revolutionary platform for cancer therapy. Despite substantial technological successes, CAP-based therapeutic systems are encounter with distinct limitations, including low control of the generated RONS, poor knowledge about its anticancer mechanisms, and challenges concerning designing, manufacturing, clinical translation, and commercialization, which must be resolved. The latest developments in CAP-based therapeutic systems for breast cancer treatment are discussed in this review. More significantly, the integration of CAP-based medicine approaches with other breast cancer therapies, including chemo- and nanotherapy is thoroughly addressed.


Assuntos
Neoplasias da Mama , Gases em Plasma , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Gases em Plasma/uso terapêutico , Espécies Reativas de Oxigênio , Espécies Reativas de Nitrogênio , Oxigênio
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