The Differential Reactive Oxygen Species Production of Tear Neutrophils in Response to Various Stimuli In Vitro

A large number of polymorphonuclear neutrophils (PMNs) invade the ocular surface during prolonged eye closure (sleep); these leukocytes are commonly referred as tear PMNs. PMNs contribute to homeostasis and possess an arsenal of inflammatory mediators to protect against pathogens and foreign materials. This study examined the ability of tear PMNs to generate reactive oxygen species (ROS), an essential killing mechanism for PMNs which can lead to oxidative stress and imbalance. Cells were collected after sleep from healthy participants using a gentle eye wash. ROS production in stimulated (phorbol-12-myristate-13-acetate (PMA), lipopolysaccharides (LPS) or N-Formylmethionyl-leucyl-phenylalanine (fMLP)) and unstimulated tear PMNs was measured using luminol-enhanced chemiluminescence for 60 min. A high level of constitutive/spontaneous ROS production was observed in tear PMNs in the absence of any stimulus. While tear PMNs were able to produce ROS in response to PMA, they failed to appropriately respond to LPS and fMLP, although fMLP-stimulated tear PMNs generated ROS extracellularly in the first three minutes. Higher ROS generation was observed in isolated tear PMNs which may be due to priming from the magnetic bead cell separation system. The differential responses of tear PMNs in ROS generation provide further evidence of their potential inflammatory roles in ocular complications involving oxidative stress.

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Impact of CD14 on Reactive Oxygen Species Production from Human Leukocytes Primed byEscherichia coliLipopolysaccharides

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/6043245 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Dmitry S. Kabanov ◽

Olga Yu. Vwedenskaya ◽

Marina A. Fokina ◽

Elena M. Morozova ◽

Sergey V. Grachev ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Reactive Oxygen ◽

Polymorphonuclear Neutrophils ◽

Ros Generation ◽

Ros Production ◽

Oxygen Species ◽

Human Pmns ◽

Species Production ◽

The Impact ◽

Priming Activity

Lipopolysaccharides (LPS) from Gram-negative bacteria prime human polymorphonuclear neutrophils (PMNs) via multicomponent receptor cluster including CD14 and MD-2·TLR4 for the enhanced release of reactive oxygen species (ROS) were triggered by bacterial derived peptideN-formyl-methionyl-leucyl-phenylalanine (fMLP). In this study, we investigated the impact of CD14 on LPS-induced priming of human PMNs for fMLP-triggered ROS generation (respiratory or oxidative) burst. Monoclonal antibodies against human CD14 (mAbs) as well as isotype-matched IgG2a did not influence significantly fMLP-triggered ROS production from LPS-unprimed PMNs. Anti-CD14 mAbs (clone UCHM-1) attenuated LPS-induced priming of PMNs as it had been mirrored by fMLP-triggered decrease of ROS production. Similar priming activity of S-LPS or Re-LPS fromEscherichia colifor fMLP-triggered ROS release from PMNs was found. Obtained results suggest that glycosylphosphatidylinositol-anchored CD14 is the key player in LPS-induced PMN priming for fMLP-triggered ROS production. We believe that blockade of CD14 on the cell surface and clinical use of anti-CD14 mAbs or their Fab fragments may diminish the production of ROS and improve outcomes during cardiovascular diseases manifested by LPS-induced inflammation.

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Extracellular Reactive Oxygen Species (ROS) Production in Fresh Donkey Sperm Exposed to Reductive Stress, Oxidative Stress and NETosis

Antioxidants ◽

10.3390/antiox10091367 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1367

Author(s):

Iván Yánez-Ortiz ◽

Jaime Catalán ◽

Yentel Mateo-Otero ◽

Marta Dordas-Perpinyà ◽

Sabrina Gacem ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Hydrogen Peroxide ◽

Selection Process ◽

Reactive Oxygen ◽

Polymorphonuclear Neutrophils ◽

Ros Production ◽

Oxygen Species ◽

Oxidative Stresses ◽

Stress Oxidative

Jenny shows a large endometrial reaction after semen influx to the uterus with a large amount of polymorphonuclear neutrophils (PMN) migrating into the uterine lumen. PMN act as a sperm selection mechanism through phagocytosis and NETosis (DNA extrudes and, together with proteins, trap spermatozoa). While a reduced percentage of spermatozoa are phagocytosed by PMN, most are found to be attached to neutrophil extracellular traps (NETs). This selection process together with sperm metabolism produces a large amount of reactive oxygen species (ROS) that influence the reproductive success. The present study aimed to determine the extracellular ROS production in both sperm and PMN. With this purpose, (1) donkey sperm were exposed to reductive and oxidative stresses, through adding different concentrations of reduced glutathione (GSH) and hydrogen peroxide (H2O2), respectively; and (2) PMN were subjected to NETosis in the presence of the whole semen, sperm, seminal plasma (SP) or other activators such as formyl-methionyl-leucyl-phenylalanine (FMLP). Extracellular ROS production (measured as H2O2 levels) was determined with the Amplex® Red Hydrogen Peroxide/Peroxidase Assay Kit. Donkey sperm showed more resilience to oxidative stress than to the reductive one, and GSH treatments led to greater H2O2 extracellular production. Moreover, not only did SP appear to be the main inducer of NETosis in PMN, but it was also able to maintain the extracellular H2O2 levels produced by sperm and NETosis.

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Reactive oxygen species in bovine oocyte maturation in vitro

Reproduction Fertility and Development ◽

10.1071/rd08198 ◽

2009 ◽

Vol 21 (4) ◽

pp. 608 ◽

Cited By ~ 43

Author(s):

Sergio A. Morado ◽

Pablo D. Cetica ◽

Martha T. Beconi ◽

Gabriel C. Dalvit

Keyword(s):

Reactive Oxygen Species ◽

Oocyte Maturation ◽

Reactive Oxygen ◽

Potassium Cyanide ◽

Ros Generation ◽

Ros Production ◽

Oxygen Species ◽

Bovine Oocyte ◽

Concomitant Reduction

The role of reactive oxygen species (ROS) in the in vitro maturation (IVM) of oocytes remains controversial. The aim of the present study was to determine possible fluctuations in ROS production during bovine oocyte IVM in the presence of different modulators of ROS generation. Cumulus–oocyte complexes were cultured in medium 199 (control) in the absence or presence of 0.6 mm cysteine, 1mm 1-choro-2,4-dinitro benzene (CDNB), 2μm diphenyliodonium, 0.5 mm N-nitro-l-arginine methyl ester or 10 μm sodium nitroprusside (SNP) at 39°C, in 5% CO2 in humidified air for 22 h. In addition, the respiratory chain effectors potassium cyanide (KCN; 1 mm) and carbonyl cyanide m-chlorophenylhydrazone (0.42 μm) were used. Meiotic maturation was determined by the presence of MII. ROS production was evaluated in denuded oocytes at different time points as the ratio of 2′,7′-dichlorodihydrofluorescein diacetate (DCHF-DA) to fluorescein diacetate (FDA). ROS levels, expressed as DCHF-DA : FDA, fluctuated throughout the 22 h of maturation depending on the treatment applied. At 12 h incubation in the presence of KCN and SNP, ROS levels were increased, whereas ROS levels after 12 h in the presence of cysteine were reduced (P < 0.05). Both CDNB and SNP impaired meiotic progression. The higher metabolic activity demand during bovine oocyte maturation coincides with a concomitant reduction in ROS generation. These results suggest that 12 h would be a critical point for bovine oocyte IVM because it is closely related to the production of ROS at this time.

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IκB kinase promotes Nrf2 ubiquitination and degradation by phosphorylating cylindromatosis, aggravating oxidative stress injury in obesity-related nephropathy

Molecular Medicine ◽

10.1186/s10020-021-00398-w ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Yin-Yin Chen ◽

Han Hong ◽

Yu-Ting Lei ◽

Jia Zou ◽

Yi-Ya Yang ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Reactive Oxygen ◽

Related Factor ◽

Ros Production ◽

Oxygen Species ◽

Stress Injury ◽

Oxidative Stress Injury ◽

Iκb Kinase

Abstract Background Obesity-related nephropathy (ORN) has become one of the leading causes of end-stage renal disease and has tripled over the past decade. Previous studies have demonstrated that decreased reactive oxygen species production may contribute to improving ORN by ameliorating oxidative stress injury. Here, IκB kinase (IKK) was hypothesized to inactivate the deubiquitination activity of cylindromatosis (CYLD) by activating the phosphorylation of CYLD, thus promoting the ubiquitination of NF-E2-related factor 2 (Nrf2) and further aggravating oxidative stress injury of the kidney in ORN. This study was aimed to confirm this hypothesis. Methods Haematoxylin and eosin (HE), periodic acid-Schiff (PAS) and Oil Red O staining were performed to assess histopathology. Dihydroethidium (DHE) staining and MDA, SOD, CAT, and GSH-PX assessments were performed to measure reactive oxygen species (ROS) production. Immunohistochemical (IHC) staining, qRT–PCR and/or western blotting were performed to assess the expression of related genes. JC-1 assays were used to measure the mitochondrial membrane potential (ΔΨm) of treated HK-2 cells. Co-immunoprecipitation experiments (Co-IP) were used to analyse the interaction between CYLD and Nrf2 in ORN. Results ORN in vivo and in vitro models were successfully constructed, and oxidative stress injury was detected in the model tissues and cells. Compared with the control groups, the phosphorylation level of CYLD increased while Nrf2 levels decreased in ORN model cells. An IKK inhibitor reduced lipid deposition, ROS production, CYLD phosphorylation levels and ΔΨm in vitro, which were reversed by knockdown of CYLD. Nrf2 directly bound to CYLD and was ubiquitinated in ORN cells. The proteasome inhibitor MG132 activated the Nrf2/ARE signalling pathway, thereby reversing the promoting effect of CYLD knockdown on oxidative stress. Conclusion IKK inactivates the deubiquitination activity of CYLD by activating the phosphorylation of CYLD, thus promoting the ubiquitination of Nrf2 and further aggravating oxidative stress injury of the kidney in ORN. This observation provided a feasible basis for the treatment of kidney damage caused by ORN.

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Reactive Oxygen Species in Host Plant Are Required for an Early Defense Response against Attack of Stagonospora nodorum Berk. Necrotrophic Effectors SnTox

Plants ◽

10.3390/plants10081586 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1586

Author(s):

Svetlana Veselova ◽

Tatyana Nuzhnaya ◽

Guzel Burkhanova ◽

Sergey Rumyantsev ◽

Igor Maksimov

Keyword(s):

Reactive Oxygen Species ◽

Early Stage ◽

Reactive Oxygen ◽

Triticum Aestivum L ◽

Redox Status ◽

Stagonospora Nodorum ◽

Ros Generation ◽

Ros Production ◽

Oxygen Species ◽

Necrotrophic Effectors

Reactive oxygen species (ROS) play a central role in plant immune responses. The most important virulence factors of the Stagonospora nodorum Berk. are multiple fungal necrotrophic effectors (NEs) (SnTox) that affect the redox-status and cause necrosis and/or chlorosis in wheat lines possessing dominant susceptibility genes (Snn). However, the effect of NEs on ROS generation at the early stages of infection has not been studied. We studied the early stage of infection of various wheat genotypes with S nodorum isolates -Sn4VD, SnB, and Sn9MN, carrying a different set of NE genes. Our results indicate that all three NEs of SnToxA, SnTox1, SnTox3 significantly contributed to cause disease, and the virulence of the isolates depended on their differential expression in plants (Triticum aestivum L.). The Tsn1–SnToxA, Snn1–SnTox1and Snn3–SnTox3 interactions played an important role in inhibition ROS production at the initial stage of infection. The Snn3–SnTox3 inhibited ROS production in wheat by affecting NADPH-oxidases, peroxidases, superoxide dismutase and catalase. The Tsn1–SnToxA inhibited ROS production in wheat by affecting peroxidases and catalase. The Snn1–SnTox1 inhibited the production of ROS in wheat by mainly affecting a peroxidase. Collectively, these results show that the inverse gene-for gene interactions between effector of pathogen and product of host sensitivity gene suppress the host’s own PAMP-triggered immunity pathway, resulting in NE-triggered susceptibility (NETS). These results are fundamentally changing our understanding of the development of this economical important wheat disease.

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A Novel Tetrapeptide Derivative Exhibits In Vitro Inhibition of Neutrophil-Derived Reactive Oxygen Species and Lysosomal Enzymes Release

Oxidative Medicine and Cellular Longevity ◽

10.1155/2013/853210 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Sumitra Miriyala ◽

Manikandan Panchatcharam ◽

Meera Ramanujam ◽

Rengarajulu Puvanakrishnan

Keyword(s):

Reactive Oxygen Species ◽

Superoxide Anion ◽

Lysosomal Enzymes ◽

Reactive Oxygen ◽

Peptide Sequence ◽

Ros Generation ◽

Oxygen Species ◽

Complement Factors

Neutrophil infiltration plays a major role in the pathogenesis of myocardial injury. Oxidative injury is suggested to be a central mechanism of the cellular damage after acute myocardial infarction. This study is pertained to the prognostic role of a tetrapeptide derivative PEP1261 (BOC-Lys(BOC)-Arg-Asp-Ser(tBu)-OtBU), a peptide sequence (39–42) of lactoferrin, studied in the modulation of neutrophil functions in vitro by measuring the reactive oxygen species (ROS) generation, lysosomal enzymes release, and enhanced expression of C proteins. The groundwork experimentation was concerned with the isolation of neutrophils from the normal and acute myocardial infarct rats to find out the efficacy of PEP1261 in the presence of a powerful neutrophil stimulant, phorbol 12-myristate 13 acetate (PMA). Stimulation of neutrophils with PMA resulted in an oxidative burst of superoxide anion and enhanced release of lysosomal enzymes and expression of complement proteins. The present study further demonstrated that the free radicals increase the complement factors in the neutrophils confirming the role of ROS. PEP1261 treatment significantly reduced the levels of superoxide anion and inhibited the release of lysosomal enzymes in the stimulated control and infarct rat neutrophils. This study demonstrated that PEP1261 significantly inhibited the effect on the ROS generation as well as the mRNA synthesis and expression of the complement factors in neutrophils isolated from infarct heart.

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Hyperglycemia Induces Generation of Reactive Oxygen Species and Accelerates Apoptotic Cell Death in Salivary Gland Cells

Pathobiology ◽

10.1159/000512639 ◽

2021 ◽

pp. 1-8

Author(s):

Naoyuki Matsumoto ◽

Daisuke Omagari ◽

Ryoko Ushikoshi-Nakayama ◽

Tomoe Yamazaki ◽

Hiroko Inoue ◽

...

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Salivary Gland ◽

Tissue Injury ◽

Ros Production ◽

Oxygen Species ◽

Saliva Secretion ◽

Salivary Gland Tissue ◽

Gland Tissue

Introduction: Type-2 diabetes mellitus (T2DM) is associated with several systemic vascular symptoms and xerostomia. It is considered that hyperglycemia-induced polyuria and dehydration cause decreased body-water volume, leading to decreased saliva secretion and, ultimately, xerostomia. In T2DM, increased production of reactive oxygen species (ROS) causes tissue damage to vascular endothelial cells as well as epithelial tissue, including pancreas and cornea. Hence, a similar phenomenon may occur in other tissues and glands in a hyperglycemic environment. Methods: Salivary gland tissue injury was examined, using T2DM model mouse (db/db). Transferase‐mediated dUTP nick‐end labeling (TUNEL) was conducted to evaluate tissue injury. The levels of malondialdehyde (MDA) and 8-hydroxy-2′-deoxyguanosine, Bax/Bcl-2 ratio were measured as indicator of oxidative stress. Moreover, in vitro ROS production and cell injury was evaluated by mouse salivary gland-derived normal cells under high-glucose condition culture. Results: In vivo and in vitro analysis showed a higher percentage of TUNEL-positive cells and higher levels of MDA and 8-hydroxy-2′-deoxyguanosine in salivary gland tissue of db/db mice. This suggests damage of saliva secretion-associated lipids and DNA by hyperglycemic-induced oxidative stress. To analyze the mechanism by which hyperglycemia promotes ROS production, mouse salivary gland-derived cells were isolated. The cell culture with high-glucose medium enhanced ROS production and promotes apoptotic and necrotic cell death. Conclusion: These findings suggest a novel mechanism whereby hyperglycemic-induced ROS production promotes salivary gland injury, resulting in hyposalivation.

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Abstract 19967: Differential Roles of the NADPH-Oxidase 1 and 2 in Platelet Activation and Thrombosis

Circulation ◽

10.1161/circ.132.suppl_3.19967 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Michael K Delaney ◽

Kyungho Kim ◽

Brian Estevez ◽

Aleksandra Stojanovic-Terpo ◽

Bo Shen ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Platelet Activation ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Reactive Oxygen ◽

Ros Generation ◽

Ros Production ◽

Oxygen Species ◽

General Role ◽

Glycoprotein Vi ◽

Activation Pathways

Objective: Reactive oxygen species (ROS) generated from activated platelets is known to regulate platelet activation. However, it remains unclear whether and how different isoforms of nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) oxidases (NOXs) play roles in different platelet activation pathways. Here we investigated the role of NOX1 and NOX2 in different platelet activation pathways using NOX1 and NOX2 knockout mice. Approach and Results: NOX1-/- platelets showed selective defects in G protein coupled receptor (GPCR)-mediated platelet activation induced by thrombin, protease-activated receptor 4 agonist peptide (PAR4AP) and thromboxane A2 analog U46619, but was not affected in platelet activation induced by collagen-related peptide (CRP), a glycoprotein VI (GPVI) agonist. In contrast, NOX2-/- platelets showed potent inhibition of CRP-induced platelet activation, and also showed partial inhibition of thrombin-induced platelet aggregation and secretion. Consistently, production of reactive oxygen species (ROS) was inhibited in NOX1-/- platelets stimulated with thrombin, but not CRP, whereas NOX2-/- platelets showed reduced ROS generation induced by CRP or thrombin. Interestingly, laser-induced arterial thrombosis was impaired in NOX2-/- mice, and in thrombocytopenic mice transfused with NOX2-/- platelets, suggesting an important role for NOX2-dependent platelet ROS production in the laser-induced injury model of thrombosis. Conclusions: NOX1 and NOX2 play differential roles in different platelet activation pathways: NOX1 mediates GPCR-mediated ROS production and platelet activation, whereas NOX2 plays a general role in GPVI- and GPCR-induced ROS production and platelet activation in vitro , and in laser-induced thrombosis in vivo .

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Plasmonic Hot-Electron Reactive Oxygen Species Generation: Fundamentals for Redox Biology

Frontiers in Chemistry ◽

10.3389/fchem.2020.591325 ◽

2020 ◽

Vol 8 ◽

Author(s):

Elisa Carrasco ◽

Juan Carlos Stockert ◽

Ángeles Juarranz ◽

Alfonso Blázquez-Castro

Keyword(s):

Reactive Oxygen Species ◽

Near Infrared ◽

Chemical Reactivity ◽

Reactive Oxygen Species Generation ◽

Reactive Oxygen ◽

Ros Generation ◽

Oxygen Species ◽

Hot Electron ◽

Redox Biology

For decades, the possibility to generate Reactive Oxygen Species (ROS) in biological systems through the use of light was mainly restricted to the photodynamic effect: the photoexcitation of molecules which then engage in charge- or energy-transfer to molecular oxygen (O2) to initiate ROS production. However, the classical photodynamic approach presents drawbacks, like per se chemical reactivity of the photosensitizing agent or fast molecular photobleaching due to in situ ROS generation, to name a few. Recently, a new approach, which promises many advantages, has entered the scene: plasmon-driven hot-electron chemistry. The effect takes advantage of the photoexcitation of plasmonic resonances in metal nanoparticles to induce a new cohort of photochemical and redox reactions. These metal photo-transducers are considered chemically inert and can undergo billions of photoexcitation rounds without bleaching or suffering significant oxidative alterations. Also, their optimal absorption band can be shape- and size-tailored in order to match any of the near infrared (NIR) biological windows, where undesired absorption/scattering are minimal. In this mini review, the basic mechanisms and principal benefits of this light-driven approach to generate ROS will be discussed. Additionally, some significant experiments in vitro and in vivo will be presented, and tentative new avenues for further research will be advanced.

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Impacts of Oxidative Stress and Antioxidants on Semen Functions

Veterinary Medicine International ◽

10.4061/2011/686137 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7 ◽

Cited By ~ 154

Author(s):

Amrit Kaur Bansal ◽

G. S. Bilaspuri

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Sperm Quality ◽

Reactive Oxygen ◽

The Body ◽

Atp Depletion ◽

Contributory Factor ◽

Ros Generation ◽

Oxygen Species ◽

High Concentrations

Oxidative stress (OS) has been considered a major contributory factor to the infertility. Oxidative stress is the result of imbalance between the reactive oxygen species (ROS) and antioxidants in the body which can lead to sperm damage, deformity, and eventually male infertility. Although high concentrations of the ROS cause sperm pathology (ATP depletion) leading to insufficient axonemal phosphorylation, lipid peroxidation, and loss of motility and viability but, many evidences demonstrate that low and controlled concentrations of these ROS play an important role in sperm physiological processes such as capacitation, acrosome reaction, and signaling processes to ensure fertilization. The supplementation of a cryopreservation extender with antioxidant has been shown to provide a cryoprotective effect on mammalian sperm quality. This paper reviews the impacts of oxidative stress and reactive oxygen species on spermatozoa functions, causes of ROS generation, and antioxidative strategies to reduce OS. In addition, we also highlight the emerging concept of utilizing OS as a tool of contraception.

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