16 results on '"NADPH oxidase (NOX)"'
Search Results
2. The NADPH Oxidase Inhibitor, Mitoapocynin, Mitigates DFP-Induced Reactive Astrogliosis in a Rat Model of Organophosphate Neurotoxicity.
- Author
-
Meyer, Christina, Grego, Elizabeth, S. Vasanthi, Suraj, Rao, Nikhil S., Massey, Nyzil, Holtkamp, Claire, Huss, Joselyn, Showman, Lucas, Narasimhan, Balaji, and Thippeswamy, Thimmasettappa
- Subjects
NADPH oxidase ,GLIOSIS ,ANIMAL disease models ,POTASSIUM channels ,NEUROTOXICOLOGY ,OXIDATIVE stress - Abstract
NADPH oxidase (NOX) is a primary mediator of superoxides, which promote oxidative stress, neurodegeneration, and neuroinflammation after diisopropylfluorophosphate (DFP) intoxication. Although orally administered mitoapocynin (MPO, 10 mg/kg), a mitochondrial-targeted NOX inhibitor, reduced oxidative stress and proinflammatory cytokines in the periphery, its efficacy in the brain regions of DFP-exposed rats was limited. In this study, we encapsulated MPO in polyanhydride nanoparticles (NPs) based on 1,6-bis(p-carboxyphenoxy) hexane (CPH) and sebacic anhydride (SA) for enhanced drug delivery to the brain and compared with a high oral dose of MPO (30 mg/kg). NOX2 (GP91
phox ) regulation and microglial (IBA1) morphology were analyzed to determine the efficacy of MPO-NP vs. MPO-oral in an 8-day study in the rat DFP model. Compared to the control, DFP-exposed animals exhibited significant upregulation of NOX2 and a reduced length and number of microglial processes, indicative of reactive microglia. Neither MPO treatment attenuated the DFP effect. Neurodegeneration (FJB+NeuN) was significantly greater in DFP-exposed groups regardless of treatment. Interestingly, neuronal loss in DFP+MPO-treated animals was not significantly different from the control. MPO-oral rescued inhibitory neuronal loss in the CA1 region of the hippocampus. Notably, MPO-NP and MPO-oral significantly reduced astrogliosis (absolute GFAP counts) and reactive gliosis (C3+GFAP). An analysis of inwardly rectifying potassium channels (Kir 4.1) in astroglia revealed a significant reduction in the brain regions of the DFP+VEH group, but MPO had no effect. Overall, both NP-encapsulated and orally administered MPO had similar effects. Our findings demonstrate that MPO effectively mitigates DFP-induced reactive astrogliosis in several key brain regions and protects neurons in CA1, which may have long-term beneficial effects on spontaneous seizures and behavioral comorbidities. Long-term telemetry and behavioral studies and a different dosing regimen of MPO are required to understand its therapeutic potential. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
3. Involvement of NOX2-derived ROS in human hepatoma HepG2 cell death induced by Entamoeba histolytica.
- Author
-
Young Ah Lee and Myeong Heon Shin
- Subjects
ENTAMOEBA histolytica ,CELL death ,REACTIVE oxygen species ,NADPH oxidase ,LIVER cells - Abstract
Entamoeba histolytica is an enteric tissue-invasive protozoan parasite causing amoebic colitis and liver abscesses in humans. Amoebic contact with host cells activates intracellular signaling pathways that lead to host cell death via generation of caspase-3, calpain, Ca
2+ elevation, and reactive oxygen species (ROS). We previously reported that various NADPH oxidases (NOXs) are responsible for ROS-dependent death of various host cells induced by amoeba. In the present study, we investigated the specific NOX isoform involved in ROS-dependent death of hepatocytes induced by amoebas. Co-incubation of hepatoma HepG2 cells with live amoebic trophozoites resulted in remarkably increased DNA fragmentation compared to cells incubated with medium alone. HepG2 cells that adhered to amoebic trophozoites showed strong dichlorodihydrofluorescein diacetate (DCF-DA) fluorescence, suggesting intracellular ROS accumulation within host cells stimulated by amoebic trophozoites. Pretreatment of HepG2 cells with the general NOX inhibitor DPI or NOX2-specific inhibitor GSK 2795039 reduced Entamoeba-induced ROS generation. Similarly, Entamoeba-induced LDH release from HepG2 cells was effectively inhibited by pretreatment with DPI or GSK 2795039. In NOX2-silenced HepG2 cells, Entamoeba-induced LDH release was also significantly inhibited compared with controls. Taken together, the results support an important role of NOX2-derived ROS in hepatocyte death induced by E. histolytica. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
4. Conjugated Linoleic Acid-Mediated Connexin-43 Remodeling and Sudden Arrhythmic Death in Myocardial Infarction.
- Author
-
Kelm, Natia Qipshidze, Solinger, Jane C., Piell, Kellianne M., and Cole, Marsha P.
- Subjects
- *
MYOCARDIAL infarction , *CONNEXIN 43 , *SUDDEN death , *VENTRICULAR tachycardia , *VENTRICULAR remodeling , *NADPH oxidase , *REACTIVE oxygen species - Abstract
Connexin 43 (Cx43) is expressed in the left and right ventricles and is primarily responsible for conducting physiological responses in microvasculature. Studies have demonstrated that NADPH oxidase (NOX) enzymes are essential in cardiac redox biology and are responsible for the generation of reactive oxygen species (ROS). NOX2 is linked to left ventricular remodeling following myocardial infarction (MI). It was hypothesized that conjugated linoleic acid (cLA) treatment increases NOX-2 levels in heart tissue and disrupts connexins between the myocytes in the ventricle. Data herein demonstrate that cLA treatment significantly decreases survival in a murine model of MI. The observance of cLA-induced ventricular tachyarrhythmia's (VT) led to the subsequent investigation of the underlying mechanism in this MI model. Mice were treated with cLA for 12 h, 24 h, 48 h, or 72 h to determine possible time-dependent changes in NOX and Cx43 signaling pathways in isolated left ventricles (LV) extracted from cardiac tissue. The results suggest that ROS generation, through the stimulation of NOX2 in the LV, triggers a decrease in Cx43 levels, causing dysfunction of the gap junctions following treatment with cLA. This cascade of events may initiate VT and subsequent death during MI. Taken together, individuals at risk of MI should use caution regarding cLA consumption. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. The Ambiguous Aspects of Oxygen
- Author
-
Gaetana Napolitano, Gianluca Fasciolo, and Paola Venditti
- Subjects
oxygen toxicity ,reactive oxygen species (ROS) ,superoxide dismutase (SOD) ,pollutants ,cigarette smoke ,NADPH oxidase (NOX) ,Analytical chemistry ,QD71-142 ,Inorganic chemistry ,QD146-197 - Abstract
For most living beings, oxygen is an essential molecule for survival, being the basis of biological oxidations, which satisfy most of the energy needs of aerobic organisms. Oxygen can also behave as a toxic agent posing a threat to the existence of living beings since it can give rise to reactive oxygen species (ROS) that can oxidise biological macromolecules, among which proteins and lipids are the preferred targets. Oxidative damage can induce cell, tissue, and organ dysfunction, which leads to severe body damage and even death. The survival of the aerobic organism depends on the development of an elaborate antioxidant defence system adapted to the normal level of atmospheric oxygen. The production of ROS in the aerobic organism can occur accidentally from exposure to pollutants or radiation, but occurs constantly during normal metabolic reactions. Cells have evolved using ROS to their advantage. Indeed, ROS are used as signalling molecules in numerous physiological processes, including muscle contraction, regulation of insulin release, and adaptation to environmental changes. Therefore, supplementation with antioxidants must be used wisely. A low level of ROS is essential for adaptation processes, so an excess of antioxidants can be harmful. Conversely, in conditions where ROS production increases, antioxidants can be useful to avoid cellular dysfunction.
- Published
- 2022
- Full Text
- View/download PDF
6. The NADPH Oxidase Inhibitor, Mitoapocynin, Mitigates DFP-Induced Reactive Astrogliosis in a Rat Model of Organophosphate Neurotoxicity
- Author
-
Christina Meyer, Elizabeth Grego, Suraj S. Vasanthi, Nikhil S. Rao, Nyzil Massey, Claire Holtkamp, Joselyn Huss, Lucas Showman, Balaji Narasimhan, and Thimmasettappa Thippeswamy
- Subjects
NADPH oxidase (NOX) ,GP91phox ,oxidative stress ,astrogliosis ,DFP (diisopropyl fluorophosphate) ,nanoparticles ,Therapeutics. Pharmacology ,RM1-950 - Abstract
NADPH oxidase (NOX) is a primary mediator of superoxides, which promote oxidative stress, neurodegeneration, and neuroinflammation after diisopropylfluorophosphate (DFP) intoxication. Although orally administered mitoapocynin (MPO, 10 mg/kg), a mitochondrial-targeted NOX inhibitor, reduced oxidative stress and proinflammatory cytokines in the periphery, its efficacy in the brain regions of DFP-exposed rats was limited. In this study, we encapsulated MPO in polyanhydride nanoparticles (NPs) based on 1,6-bis(p-carboxyphenoxy) hexane (CPH) and sebacic anhydride (SA) for enhanced drug delivery to the brain and compared with a high oral dose of MPO (30 mg/kg). NOX2 (GP91phox) regulation and microglial (IBA1) morphology were analyzed to determine the efficacy of MPO-NP vs. MPO-oral in an 8-day study in the rat DFP model. Compared to the control, DFP-exposed animals exhibited significant upregulation of NOX2 and a reduced length and number of microglial processes, indicative of reactive microglia. Neither MPO treatment attenuated the DFP effect. Neurodegeneration (FJB+NeuN) was significantly greater in DFP-exposed groups regardless of treatment. Interestingly, neuronal loss in DFP+MPO-treated animals was not significantly different from the control. MPO-oral rescued inhibitory neuronal loss in the CA1 region of the hippocampus. Notably, MPO-NP and MPO-oral significantly reduced astrogliosis (absolute GFAP counts) and reactive gliosis (C3+GFAP). An analysis of inwardly rectifying potassium channels (Kir4.1) in astroglia revealed a significant reduction in the brain regions of the DFP+VEH group, but MPO had no effect. Overall, both NP-encapsulated and orally administered MPO had similar effects. Our findings demonstrate that MPO effectively mitigates DFP-induced reactive astrogliosis in several key brain regions and protects neurons in CA1, which may have long-term beneficial effects on spontaneous seizures and behavioral comorbidities. Long-term telemetry and behavioral studies and a different dosing regimen of MPO are required to understand its therapeutic potential.
- Published
- 2023
- Full Text
- View/download PDF
7. ROS and DNA repair in spontaneous versus agonist-induced NETosis: Context matters
- Author
-
Dhia Azzouz and Nades Palaniyar
- Subjects
neutrophil extracellular traps (NETs) ,spontaneous NETosis ,reactive oxygen species (ROS) ,NADPH oxidase (NOX) ,DNA repair ,base excision repair (BER) ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Reactive oxygen species (ROS) is essential for neutrophil extracellular trap formation (NETosis). Nevertheless, how ROS induces NETosis at baseline and during neutrophil activation is unknown. Although neutrophils carry DNA transcription, replication and repair machineries, their relevance in the short-lived mature neutrophils that carry pre-synthesized proteins has remained a mystery for decades. Our recent studies show that (i) NETosis-inducing agonists promote NETosis-specific kinase activation, genome-wide transcription that helps to decondense chromatin, and (ii) excess ROS produced by NADPH oxidase activating agonists generate genome-wide 8-oxy-guanine (8-OG), and the initial steps of DNA repair are needed to decondense chromatin in these cells. These steps require DNA repair proteins necessary for the assembly and nicking at the damaged DNA sites (poly ADP ribose polymerase PARP, apurinic endonuclease APE1 and DNA ligase), but not the enzymes that mediate the repair DNA synthesis (Proliferating cell nuclear antigen (PCNA) and DNA Polymerases). In this study, we show that (i) similar to agonist-induced NETosis, inhibition of early steps of oxidative DNA damage repair proteins suppresses spontaneous NETosis, but (ii) the inhibition of late stage repair proteins DNA polymerases and PCNA drastically promotes baseline NETosis. Hence, in the absence of excessive ROS generation and neutrophil activation, DNA repair mediated by PCNA and DNA polymerases is essential to prevent chromatin decondensation and spontaneous NETosis. These findings indicate that ROS, oxidative DNA damage, transcription and DNA repair differentially regulate spontaneous and agonist-induced NETosis. Therefore, context matters.
- Published
- 2022
- Full Text
- View/download PDF
8. NADPH Oxidase Isoforms in COPD Patients and Acute Cigarette Smoke-Exposed Mice: Induction of Oxidative Stress and Lung Inflammation.
- Author
-
Wang, Xinjing, Murugesan, Priya, Zhang, Pan, Xu, Shiqing, Peng, Liang, Wang, Chen, and Cai, Hua
- Subjects
NADPH oxidase ,PNEUMONIA ,MYOFIBROBLASTS ,OXIDATIVE stress ,CHRONIC obstructive pulmonary disease - Abstract
Conclusions Our data demonstrate for the first time that NOX isoforms NOX1, NOX2, NOX4, and NOX5 all remained active in lung tissues of end-stage COPD patients, indicating critical roles of these enzymes in the pathogenesis of the advanced disease. Compared to the donor group, the protein expression of NOX isoforms NOX1, NOX2, NOX4, and NOX5 was significantly upregulated in lung tissue sections of patients with end-stage COPD. Chronic obstructive pulmonary disease (COPD), NOX1, NOX2, acute cigarette smoke (ACS), oxidative stress, lung inflammation, NADPH oxidase (NOX), NOX4, NOX5 Discussion In the present study, we investigated the expression profiles of NOX isoforms in end-stage COPD patients and the potential differential roles of NOX isoforms in ACS induced oxidative stress and lung inflammation in mice as a model for early COPD or early-stage COPD. Keywords: chronic obstructive pulmonary disease (COPD); NADPH oxidase (NOX); NOX1; NOX2; NOX4; NOX5; acute cigarette smoke (ACS); oxidative stress; lung inflammation EN chronic obstructive pulmonary disease (COPD) NADPH oxidase (NOX) NOX1 NOX2 NOX4 NOX5 acute cigarette smoke (ACS) oxidative stress lung inflammation N.PAG N.PAG 19 08/29/22 20220801 NES 220801 1. [Extracted from the article]
- Published
- 2022
- Full Text
- View/download PDF
9. Exercise Affects the Formation and Recovery of Alcoholic Liver Disease through the IL-6–p47 phox Oxidative–Stress Axis.
- Author
-
Cui, Wei, Li, Xiang, Xue, Weiyue, Wei, Huiting, Zhou, Gang, Qiu, Ye, and Cui, Di
- Subjects
- *
EXERCISE therapy , *BLOOD proteins , *ALCOHOL drinking , *ACTIVE recovery , *INTRAPERITONEAL injections - Abstract
(1) Background: To explore the effect of exercise on the formation and recovery of alcoholic liver disease (ALD) and whether the IL-6–p47phox oxidative–stress axis is involved in that process. (2) Methods: Firstly, 23 six-week-old male C57BL/6J mice were randomly divided into the Con group, ALD group, ALD + NOXI group, ALD + Ex group, and ALD + Ex + NOXI group. The Liber–DeCarli alcoholic liquid diet was used for 6 weeks to establish the ALD mice model, and the Con group was given the TP4030C control diet. The remaining groups were fed with the TP4030B alcoholic diet, and exercise intervention was started after the ALD model establishment and lasted for another 6 weeks, with or without administration of the NOX inhibitor apocynin by intraperitoneal injection on every exercise training day. Secondly, 28 mice were randomly divided into the Sed group, Eth group, Eth + Ex group and Eth + Ex + NOXI group. The Sed group was given the TP4030C control diet. The remaining groups were fed with the TP4030B alcoholic diet and exercise intervention was started synchronously combined with or without administration of intraperitoneal apocynin injections on every exercise training day for 5 weeks. After each individual experiment was accomplished, physiological assessment and biochemical analysis of blood and tissue samples were examined. (3) Results: The levels of TG in serum and IL-6 protein content in liver tissue in the ALD group were significantly increased compared to the Con group (p < 0.05); compared with ALD, p47phox expression in muscle was increased significantly in the ALD + NOXI group (p < 0.05), and TG in serum decreased in the ALD + Ex group (p < 0.05). TG in serum, AST/ALT ratio, and IL-6 content in both liver and muscle decreased (p < 0.05) in the ALD + Ex + NOXI group with MDA in muscle significantly increased (p < 0.01). The AST/ALT ratio, TG in serum, SOD in liver, and p47phox in both liver and muscle in the ALD + Ex + NOXI group were significantly decreased compared with the ALD + NOXI group (p < 0.01). Compared with the ALD + Ex group, the liver index and HDL-C levels in serum were decreased (p < 0.05) in the ALD + Ex + NOXI group. The degree of hepatocyte steatosis and inflammatory infiltration were ameliorated after exercise intervention. In the Eth group, the relative epididymal fat content, HDL-C level, and AST/ALT ratio were significantly decreased, and TG and gp91phox in liver were significantly higher than in the Sed group (p < 0.05, p < 0.01). Compared with the Eth group, the AST/ALT ratio, MDA in the liver, and NOX4 and p47phox protein expression in the liver were significantly increased, and body weight decreased significantly in the Eth + Ex group (p < 0.05, p < 0.01), as did TG in the liver and MDA in muscle. In the th + Ex + NOXI group, gp91phox expression in the liver and body weight were significantly decreased (p < 0.05, p < 0.01). In the Eth + Ex + NOXI group, the ratio of AST/ALT and MDA in muscle were increased when compared with the Eth + Ex group, and the protein expression of gp91phox and p47phox were much lower (p < 0.01). (4) Conclusions: 6 weeks of exercise intervention during the recovery phase of ALD ameliorates hepatocyte damage and dyslipidemia through the IL-6–p47phox oxidative–stress axis, and applying a NOX inhibitor in combination could optimize this. However, drinking alcohol during exercise exacerbates dyslipidemia and oxidative stress, with hepatocyte IL-6–p47phox downregulated. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
10. Basidiomycota Fungi and ROS: Genomic Perspective on Key Enzymes Involved in Generation and Mitigation of Reactive Oxygen Species
- Author
-
Hans Mattila, Janina Österman-Udd, Tuulia Mali, and Taina Lundell
- Subjects
reactive oxygen species (ROS) ,Basidiomycota ,superoxide dismutase ,catalase (CAT) ,thioredoxin (TRX) family proteins ,NADPH oxidase (NOX) ,Plant culture ,SB1-1110 - Abstract
Our review includes a genomic survey of a multitude of reactive oxygen species (ROS) related intra- and extracellular enzymes and proteins among fungi of Basidiomycota, following their taxonomic classification within the systematic classes and orders, and focusing on different fungal lifestyles (saprobic, symbiotic, pathogenic). Intra- and extracellular ROS metabolism-involved enzymes (49 different protein families, summing 4170 protein models) were searched as protein encoding genes among 63 genomes selected according to current taxonomy. Extracellular and intracellular ROS metabolism and mechanisms in Basidiomycota are illustrated in detail. In brief, it may be concluded that differences between the set of extracellular enzymes activated by ROS, especially by H2O2, and involved in generation of H2O2, follow the differences in fungal lifestyles. The wood and plant biomass degrading white-rot fungi and the litter-decomposing species of Agaricomycetes contain the highest counts for genes encoding various extracellular peroxidases, mono- and peroxygenases, and oxidases. These findings further confirm the necessity of the multigene families of various extracellular oxidoreductases for efficient and complete degradation of wood lignocelluloses by fungi. High variations in the sizes of the extracellular ROS-involved gene families were found, however, among species with mycorrhizal symbiotic lifestyle. In addition, there are some differences among the sets of intracellular thiol-mediation involving proteins, and existence of enzyme mechanisms for quenching of intracellular H2O2 and ROS. In animal- and plant-pathogenic species, extracellular ROS enzymes are absent or rare. In these fungi, intracellular peroxidases are seemingly in minor role than in the independent saprobic, filamentous species of Basidiomycota. Noteworthy is that our genomic survey and review of the literature point to that there are differences both in generation of extracellular ROS as well as in mechanisms of response to oxidative stress and mitigation of ROS between fungi of Basidiomycota and Ascomycota.
- Published
- 2022
- Full Text
- View/download PDF
11. NADPH Oxidase Isoforms in COPD Patients and Acute Cigarette Smoke-Exposed Mice: Induction of Oxidative Stress and Lung Inflammation
- Author
-
Xinjing Wang, Priya Murugesan, Pan Zhang, Shiqing Xu, Liang Peng, Chen Wang, and Hua Cai
- Subjects
chronic obstructive pulmonary disease (COPD) ,NADPH oxidase (NOX) ,NOX1 ,NOX2 ,NOX4 ,NOX5 ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Cigarette smoke (CS) is a major risk factor for chronic obstructive pulmonary disease (COPD), which represents the third leading cause of death worldwide. CS induces reactive oxygen species (ROS) production, leading to pulmonary inflammation and remodeling. NADPH oxidases (NOXs) represent essential sources of ROS production in the cardiovascular system. Whether and how NOX isoforms are activated in COPD patients and in response to acute cigarette smoke (ACS) remains incompletely understood. In the present study, the expression of NOX isoforms was examined in the lungs of end-stage COPD patients. In addition, mice silenced of NOX1 or NOX4 expression using in vivo RNA interference (RNAi), and NOX2-deficient (NOX2−/y) mice, were exposed to ACS for 1 h using a standard TE-10B smoking machine. In lung sections isolated from COPD patients undergoing lung transplantation, protein expression of NOX1, NOX2, NOX4, or NOX5 was markedly upregulated compared to non-smoking donor controls. Likewise, ACS upregulated protein expression of NOX1, NOX2, and NOX4, production of ROS, inflammatory cell infiltration, and mRNA expression of proinflammatory cytokines TNF-α and KC in the mouse lung. In vivo RNAi knockdown of NOX1 or NOX4 decreased ACS induced ROS production, inflammatory cell influx, and the expression of TNF-α and KC, which were accompanied by inhibition of the NF-κB-COX-2 axis. Although ACS induced ROS production was reduced in the lungs of NOX2−/y mice, inflammatory cell influx and expression of NF-κB/COX-2 were increased. Taken together, our results demonstrate for the first time that NOX isoforms 1, 2, 4 and 5 all remain activated in end-stage COPD patients, while NOX1 and NOX4 mediate oxidative stress and inflammatory responses in response to acute cigarette smoke. Therefore, targeting different isoforms of NOX might be necessary to treat COPD at different stages of the disease, which represents novel mechanistic insights enabling improved management of the devastating disease.
- Published
- 2022
- Full Text
- View/download PDF
12. Production of extracellular superoxide radical in microorganisms and its environmental implications: A review.
- Author
-
He, Zhanfei, Li, Qunqun, Xu, Yao, Zhang, Daoyong, and Pan, Xiangliang
- Subjects
POLLUTANTS ,RADICALS (Chemistry) ,EMERGING contaminants ,HEAVY metals ,NADPH oxidase ,NICOTINAMIDE adenine dinucleotide phosphate ,SUPEROXIDES - Abstract
Extracellular superoxide radical (O 2
•− ) is ubiquitous in microbial environments and has significant implications for pollutant transformation. Microbial extracellular O 2•− can be produced through multiple pathways, including electron leakage from the respiratory electron transport chain (ETC), NADPH oxidation by the transmembrane NADPH oxidase (NOX), and extracellular reactions. Extracellular O 2•− significantly influences the geochemical processes of various substances, including toxic metals and refractory organic pollutants. On one hand, extracellular O 2•− can react with variable-valence metals and detoxify certain highly toxic metals, such as As(III), Cr(VI), and Hg(II). On the other hand, extracellular O 2•− can directly or indirectly (via Bio-Fenton) degrade many organic pollutants, including a variety of emerging contaminants. In this work, we summarize the production mechanisms of microbial extracellular O 2•− , review its roles in the transformation of environmental pollutants, and discuss the potential applications, limiting factors, and future research directions in this field. [Display omitted] • ETC and NOX are the main production pathways of microbial extracellular O 2•− . • Environmental stresses usually increase the levels of microbial extracellular O 2•− . • Extracellular O 2•− can oxidize or reduce variable metals (Fe, Mn, Cr, Ag, Sb, etc.). • Extracellular O 2•− can degrade refractory organic pollutants (plastics, PPCPs, etc.). [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
13. Involvement of NOX2-derived ROS in human hepatoma HepG2 cell death induced by Entamoeba histolytica.
- Author
-
Lee YA and Shin MH
- Subjects
- Humans, Reactive Oxygen Species metabolism, Hep G2 Cells, Entamoeba histolytica metabolism, Carcinoma, Hepatocellular, Liver Neoplasms
- Abstract
Entamoeba histolytica is an enteric tissue-invasive protozoan parasite causing amoebic colitis and liver abscesses in humans. Amoebic contact with host cells activates intracellular signaling pathways that lead to host cell death via generation of caspase-3, calpain, Ca2+ elevation, and reactive oxygen species (ROS). We previously reported that various NADPH oxidases (NOXs) are responsible for ROS-dependent death of various host cells induced by amoeba. In the present study, we investigated the specific NOX isoform involved in ROS-dependent death of hepatocytes induced by amoebas. Co-incubation of hepatoma HepG2 cells with live amoebic trophozoites resulted in remarkably increased DNA fragmentation compared to cells incubated with medium alone. HepG2 cells that adhered to amoebic trophozoites showed strong dichlorodihydrofluorescein diacetate (DCF-DA) fluorescence, suggesting intracellular ROS accumulation within host cells stimulated by amoebic trophozoites. Pretreatment of HepG2 cells with the general NOX inhibitor DPI or NOX2-specific inhibitor GSK 2795039 reduced Entamoeba-induced ROS generation. Similarly, Entamoeba-induced LDH release from HepG2 cells was effectively inhibited by pretreatment with DPI or GSK 2795039. In NOX2-silenced HepG2 cells, Entamoeba-induced LDH release was also significantly inhibited compared with controls. Taken together, the results support an important role of NOX2-derived ROS in hepatocyte death induced by E. histolytica.
- Published
- 2023
- Full Text
- View/download PDF
14. Discovery of a NADPH oxidase inhibitor, (E)-3-cyclohexyl-5-(4-((2-hydroxyethyl)(methyl)amino)benzylidene)-1-methyl-2-thioxoimidazolidin-4-oneone, as a novel therapeutic for Parkinson's disease.
- Author
-
Shim, Seunghwan, Jeong, Da Un, Kim, Hyemi, Kim, Chae Yun, Park, Hyejun, Jin, Yinglan, Kim, Kyung Min, Lee, Hwa Jeong, Kim, Dong Hwan, Bae, Yun Soo, and Choi, Yongseok
- Subjects
- *
PARKINSON'S disease , *NADPH oxidase , *ORAL drug administration , *REACTIVE oxygen species , *CHEMILUMINESCENCE assay , *DOPAMINE receptors , *NICOTINAMIDE adenine dinucleotide phosphate , *LIPOPOLYSACCHARIDES - Abstract
Several lines of evidence indicated that generation of NADPH oxidase (Nox)-mediated reactive oxygen species are associated with neuronal inflammation, leading to Parkinson's disease (PD). Novel benzylidene-1-methyl-2-thioxoimidazolidin-one derivatives as Nox inhibitors were designed and synthesized in order to increase blood-brain barrier (BBB) permeability to target Nox in brain cells. In lucigenin chemiluminescence assay, eight compounds showed excellent inhibition activity against NADPH oxidases and parallel artificial membrane permeability assay (PAMPA) identified compound 11 with high passive permeability. To validate the effect of compound 11 on neuronal inflammation, we tested the regulatory activity of compound 11 in lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines in BV-2 microglial cells and LPS-mediated microglial migration. Treatment of BV2 cells with compound 11 resulted in suppressed production of pro-inflammatory cytokines and migration activity of BV2 cells in response to LPS. To evaluate the therapeutic efficacy of compound 11 in PD animal model, compound 11 was applied to MPTP-induced PD mouse model. Oral administration of compound 11 (30 mg/kg/daily, 4 weeks) into the mice resulted in suppression of dopaminergic neuronal death in substantia nigra (SN) and in striatum as well as inhibition of microglial migration into SN. These results implicate compound 11 as a novel therapeutic agent for the treatment of PD. [Display omitted] • ROS overproduction by NOX plays a key role in neuronal damage critical in Parkinson's disease. • Benzylidene-1-methyl-2-thioxoimidazolidinone derivatives showed potent inhibitory activities against NADPH oxidases. • Compound 11 could cross BBB and suppressed production of pro-inflammatory cytokines and migration activity of BV2 cells in response to LPS. • Compound 11 showed a good therapeutic efficacy in MPTP-induced Parkinson's disease animal model. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
15. Identification of the NADPH Oxidase (Nox) Subtype and the Source of Superoxide Production in the Micturition Centre.
- Author
-
Wu, Qin, Gurpinar, Ayse, Roberts, Maxwell, Camelliti, Patrizia, Ruggieri Sr., Michael R., and Wu, Changhao
- Subjects
- *
NADPH oxidase , *URINATION , *SUPEROXIDES , *REACTIVE oxygen species , *BLADDER , *OXYGEN - Abstract
Simple Summary: Reactive oxygen species (ROS) are chemically active oxygen-containing molecules and overproduction of ROS can cause oxidative damage to cells and tissues in the body. Oxidative damage to brain cells can not only cause lesions to the brain but also lead to disorders in peripheral organs under the control of the corresponding brain centres, such as the urinary bladder. A unique class of enzymes that produce ROS are the special oxidising enzymes called "Nox" enzymes. These are the body's only enzymes that can be selectively controlled without affecting normal cell activity. Therefore, Nox enzymes are considered to be a drug target. Whether Nox exists in the brain centres that control urination has not been examined. We investigated whether the type 2 Nox enzyme-Nox 2 exists in the brain urination control centre and whether such a Nox enzyme is functional. Our results show that the brain urination control centre has Nox 2 proteins, and the Nox enzyme produces a significant amount of ROS, higher than heart tissue, suggesting the importance of Nox-associated ROS production in physiology and pathology. These findings lay the groundwork for future investigation into Nox 2 and the associated oxidative damage in brain urination control centres and consequent bladder abnormalities. Oxidative inflammatory damage to specialised brain centres may lead to dysfunction of their associated peripheral organs, such as the bladder. However, the source of reactive oxygen species (ROS) in specific brain regions that regulate bladder function is poorly understood. Of all ROS-generating enzymes, the NADPH oxidase (Nox) family produces ROS as its sole function and offers an advantage over other enzymes as a drug-targetable molecule to selectively control excessive ROS. We investigated whether the Nox 2 subtype is expressed in the micturition regulatory periaqueductal gray (PAG) and Barrington's nucleus (pontine micturition centre, PMC) and examined Nox-derived ROS production in these structures. C57BL/6J mice were used; PAG, PMC, cardiac tissue, and aorta were isolated. Western blot determined Nox 2 expression. Lucigenin-enhanced chemiluminescence quantified real-time superoxide production. Western blot experiments demonstrated the presence of Nox 2 in PAG and PMC. There was significant NADPH-dependent superoxide production in both brain tissues, higher than that in cardiac tissue. Superoxide generation in these brain tissues was significantly suppressed by the Nox inhibitor diphenyleneiodonium (DPI) and also reduced by the Nox-2 specific inhibitor GSK2795039, comparable to aorta. These data provide the first evidence for the presence of Nox 2 and Nox-derived ROS production in micturition centres. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
16. [Effect of PKC inhibitor on renal podocyte slit diaphragm protein expression in exhausted rats].
- Author
-
An JF, Li H, Yang F, Xie WJ, Li PF, Liu J, Cui D, and Zhou G
- Subjects
- Animals, Blood Glucose, Kidney, Male, Proteinuria, Rats, Rats, Sprague-Dawley, Reactive Oxygen Species, Urea, Uric Acid, Podocytes
- Abstract
Objective: To investigate the expression level of podocyte slit diaphragm protein in rats after one-time exhaustive exercise, to explore the effect of PKC inhibitor on the protein expression level, and to reveal the mechanism of PKC in the formation of exercise-induced proteinuria. Methods: Thirty male SD rats were randomly divided into control group (C), exercise group (E) and exercise combining with PKC inhibitor group (EPI), with 10 rats in each group. Rats in group E and EPI performed one single bout of exhaustive exercise (25 m/min), rats in group EPI were intraperitoneally injected with a PKC inhibitor (chelerythrine, 5 mg/kg) 1 day and 1 hour before exercise respectively, while rats in group C and E were injected with the same volume of saline. Results: ①Compared with group C, the levels of urine protein, uric acid, urine sugar, blood urea, and blood uric acid of rats in group E were increased significantly ( P <0.05), the level of blood glucose was reduced significantly ( P <0.01), and renal ROS production was increased significantly ( P <0.01). The expressions of nephrin and podocin protein in renal tissue were decreased significantly ( P < 0.05), while the expressions of PKC, Nox2, and Nox4 protein were increased significantly ( P <0.05). ②Compared with group E, the levels of urinary protein,urine glucose and blood urea in EPI group were decreased significantly ( P <0.05), the level of blood glucose was increased significantly ( P <0.01), renal ROS production was reduced significantly ( P <0.01). the expressions of nephrin and podocin protein in renal tissues of the EPI group were increased significantly ( P <0.05), while the expressions of PKC and Nox2 protein was reduced significantly ( P <0.05, P <0.01). Conclusion: One-time exhaustive exercise can down-regulate the expressions of nephrin and podocin through PKC/Nox/ROS pathways in the kidney of rats; PKC inhibitor alleviates the decrease in the expression of podocyte slit diaphragm protein caused by exhaustive exercise, and prevents the occurrence of exercise-induced proteinuria.
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.