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1.
J. venom. anim. toxins incl. trop. dis ; 27: e20200179, 2021. tab, graf, ilus
Article in English | ID: biblio-1279402

ABSTRACT

Neutrophils play a pivotal role in innate immunity and in the inflammatory response. Neutrophils are very motile cells that are rapidly recruited to the inflammatory site as the body first line of defense. Their bactericidal activity is due to the release into the phagocytic vacuole, called phagosome, of several toxic molecules directed against microbes. Neutrophil stimulation induces release of this arsenal into the phagosome and induces the assembly at the membrane of subunits of the NAPDH oxidase, the enzyme responsible for the production of superoxide anion that gives rise to other reactive oxygen species (ROS), a process called respiratory burst. Altogether, they are responsible for the bactericidal activity of the neutrophils. Excessive activation of neutrophils can lead to extensive release of these toxic agents, inducing tissue injury and the inflammatory reaction. Envenomation, caused by different animal species (bees, wasps, scorpions, snakes etc.), is well known to induce a local and acute inflammatory reaction, characterized by recruitment and activation of leukocytes and the release of several inflammatory mediators, including prostaglandins and cytokines. Venoms contain several molecules such as enzymes (phospholipase A2, L-amino acid oxidase and proteases, among others) and peptides (disintegrins, mastoporan, parabutoporin etc.). These molecules are able to stimulate or inhibit ROS production by neutrophils. The present review article gives a general overview of the main neutrophil functions focusing on ROS production and summarizes how venoms and venom molecules can affect this function.(AU)


Subject(s)
Animals , Poisons/administration & dosage , Reactive Oxygen Species , NADPH Oxidases , L-Amino Acid Oxidase , Neutrophils , Anti-Inflammatory Agents
2.
Rev. cuba. hematol. inmunol. hemoter ; 36(2): e1102, abr.-jun. 2020. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1149897

ABSTRACT

Introducción: La enfermedad granulomatosa crónica es una inmunodeficiencia primaria causada por mutaciones en la enzima NADPH oxidasa. Esta compromete la producción de especies reactivas del oxígeno, que son importantes contra patógenos. La prueba de la oxidación de la dihidrorodamina es un método eficaz para diagnosticar la enfermedad. Objetivo: Demostrar la utilidad de la prueba de la oxidación de la dihidrorodamina y del patrón de herencia en la confirmación del diagnóstico de la enfermedad granulomatosa crónica de un paciente. Métodos: Estudio de caso de una familia con diagnóstico de enfermedad granulomatosa crónica. Se tomó muestra de sangre periférica para citometría de flujo a tres individuos. Se realizó la prueba de la oxidación de la dihidrorodamina bajo estímulo con acetato de forbolmiristato y se evaluaron las subpoblaciones linfocitarias. Las muestras se leyeron en un citómetro GALLIOS, Beckman Coulter. Los datos obtenidos se analizaron en el programa informático Kaluza. Resultados: El paciente masculino tuvo un valor de oxidación de la dihidrorodamina positiva de 0,87 por ciento, que confirmó un patrón de herencia ligado al cromosoma X; mientras que la madre y hermana gemela portadoras tuvieron valores de 46,76 por ciento y 37,32 por ciento, respectivamente. Se encontraron alteraciones en las subpoblaciones linfocitarias. Conclusiones: La prueba de la oxidación de la dihidrorodamina es un método muy efectivo, rápido y sencillo que confirma el diagnóstico de la enfermedad granulomatosa crónica y determina el patrón de herencia y fenotipo de la enfermedad. Además, permite identificar a las mujeres portadoras según la distribución de los neutrófilos normales y los que tienen el gen CYBB mutado(AU)


Introduction: Chronic granulomatous disease is a primary immunodeficiency caused by mutations in the NADPH oxidase enzymes. This compromises the production of oxygen reactive species, which are important against pathogens. The dihydrorhodamine oxidation test is an effective method for diagnosing the disease. Objective: To demonstrate the usefulness of the dihydrorhodamine oxidation test and the inheritance pattern in confirming the diagnosis of chronic granulomatous disease in a patient. Methods: A case study of a family with a diagnosis of chronic granulomatous disease. A peripheral blood sample was taken from three individuals and by flow cytometry. The dihydrorhodamine oxidation test was performed under stimulation with phorbolmyristate acetate, and lymphocyte subpopulations were evaluated. The samples were read on a GALLIOS, Beckman Coulter cytometer. The data obtained were analyzed using the computer program Kaluza. Results: The male patient had a positive dihydrorhodamine oxidation value of 0.87 percent, which confirmed an inheritance pattern linked to the X chromosome; while the carrier mother and twin sister had values 8203;8203;of 46.76 percent and 37.32 percent, respectively. Alterations were found in the lymphocyte subpopulations. Conclusions: The dihydrorhodamine oxidation test is a very effective, fast and simple method that confirms the diagnosis of chronic granulomatous disease and determines the inheritance pattern and phenotype of the disease. In addition, it allows the identification of female carriers according to the distribution of normal neutrophils and those with the CYBB mutation(AU)


Subject(s)
Humans , Carrier State/congenital , NADPH Oxidases/analysis , Inheritance Patterns/genetics , Granulomatous Disease, Chronic/diagnosis , Case Reports , Cuba , Genetic Carrier Screening/methods , Medical History Taking/methods
3.
Article in English | WPRIM | ID: wpr-785705

ABSTRACT

BACKGROUND: Chronic exposure to elevated levels of free fatty acids contributes to pancreatic β-cell dysfunction. Although it is well known that metformin induces cellular energy depletion and a concomitant activation of AMP-activated protein kinase (AMPK) through inhibition of the respiratory chain, previous studies have shown inconsistent results with regard to the action of metformin on pancreatic β-cells. We therefore examined the effects of metformin on pancreatic β-cells under lipotoxic stress.METHODS: NIT-1 cells and mouse islets were exposed to palmitate and treated with 0.05 and 0.5 mM metformin. Cell viability, glucose-stimulated insulin secretion, cellular adenosine triphosphate, reactive oxygen species (ROS) levels and Rho kinase (ROCK) activities were measured. The phosphorylation of AMPK was evaluated by Western blot analysis and mRNA levels of endoplasmic reticulum (ER) stress markers and NADPH oxidase (NOX) were measured by real-time quantitative polymerase chain reaction analysis.RESULTS: We found that metformin has protective effects on palmitate-induced β-cell dysfunction. Metformin at a concentration of 0.05 mM inhibits NOX and suppresses the palmitate-induced elevation of ER stress markers and ROS levels in a AMPK-independent manner, whereas 0.5 mM metformin inhibits ROCK activity and activates AMPK.CONCLUSION: This study suggests that the action of metformin on β-cell lipotoxicity was implemented by different molecular pathways depending on its concentration. Metformin at a usual therapeutic dose is supposed to alleviate lipotoxic β-cell dysfunction through inhibition of oxidative stress and ER stress.


Subject(s)
Adenosine Triphosphate , AMP-Activated Protein Kinases , Animals , Blotting, Western , Cell Survival , Electron Transport , Endoplasmic Reticulum , Endoplasmic Reticulum Stress , Fatty Acids, Nonesterified , Insulin , Insulin-Secreting Cells , Metformin , Mice , NADPH Oxidases , Oxidative Stress , Phosphorylation , Polymerase Chain Reaction , Reactive Oxygen Species , rho-Associated Kinases , RNA, Messenger
4.
Article in English | WPRIM | ID: wpr-764060

ABSTRACT

BACKGROUND AND OBJECTIVES: Patients suffer from long-term diabetes can result in severe complications in multiple organs through induction of vascular dysfunctions. However, the effects of chronic hyperglycemic conditions on hematopoiesis and the microenvironment in the bone marrow (BM) are not yet well understood. METHODS: BM cells were harvested from femurs of mice and analyzed using flow cytometry. Human PVCs were cultured in serum-free α-MEM. After 24hrs, PVC-CM was collected and filtered through a 0.22 μm filter. RESULTS: In this study, we showed that hyperglycemia alters hematopoietic composition in the BM, which can partially be restored via paracrine mechanisms, including perivascular cells (PVCs) and NADPH oxidase (NOX) inhibition in mice with streptozotocin-induced diabetes. Prolonged hyperglycemic conditions resulted in an increase in the frequency and number of long-term hematopoietic stem cells as well as the number of total BM cells. The altered hematopoiesis in the BM was partially recovered by treatment with PVC-derived conditioned medium (CM). Long-term diabetes also increased the number of myeloid-derived suppressor cells in the BM, which was partially restored by the administration of PVC-CM and diphenyleneiodonium (DPI), a NOX inhibitor. We further showed the downregulation of ERK and p38 phosphorylation in BM cells of diabetic mice treated with PVC-CM and DPI. This may be associated with dysfunction of hematopoietic cells and promotion of subsequent diabetic complications. CONCLUSIONS: Our data suggested that alterations in BM hematopoietic composition due to prolonged hyperglycemic conditions might be restored by improvement of the hematopoietic microenvironment and modulation of NOX activity.


Subject(s)
Animals , Bone Marrow , Culture Media, Conditioned , Diabetes Complications , Down-Regulation , Femur , Flow Cytometry , Hematopoiesis , Hematopoietic Stem Cells , Humans , Hyperglycemia , Mice , NADP , NADPH Oxidases , Phosphorylation
5.
Mycobiology ; : 105-111, 2019.
Article in English | WPRIM | ID: wpr-760521

ABSTRACT

Many of the fungicides and antibiotics currently available against plant pathogens are of limited use due to the emergence of resistant strains. In this study, we examined the effects of diphenyleneiodonium chloride (DPIC), an inhibitor of the superoxide producing enzyme NADPH oxidase, against fungal and bacterial plant pathogens. We found that DPIC inhibits fungal spore germination and bacterial cell proliferation. In addition, we demonstrated the potent antibacterial activity of DPIC using rice heads infected with the bacterial pathogen Burkholderia glumae which causes bacterial panicle blight (BPB). We found that treatment with DPIC reduced BPB when applied during the initial flowering stage of the rice heads. These results suggest that DPIC could serve as a new and useful antimicrobial agent in agriculture.


Subject(s)
Agriculture , Anti-Bacterial Agents , Burkholderia , Cell Proliferation , Flowers , Germination , Head , NADPH Oxidases , Plants , Spores, Fungal , Superoxides
6.
Korean Circulation Journal ; : 866-876, 2019.
Article in English | WPRIM | ID: wpr-759469

ABSTRACT

BACKGROUND AND OBJECTIVES: Elevated endothelin (ET)-1 level is strongly correlated with the pathogenesis of pulmonary arterial hypertension (PAH). Expression level of nicotinamide adenine dinucleotide phosphate oxidase (NOX) 4 is increased in the PAH patients. Ambrisentan, a selective endothelin receptor A (ERA) antagonist, is widely used in PAH therapy. The current study was undertaken to evaluate the effects of ambrisentan treatment in the monocrotaline (MCT)-induced PAH rat model. METHODS: Rats were categorized into control group (C), monocrotaline group (M) and ambrisentan group (Am). The M and Am were subcutaneously injected 60 mg/kg MCT at day 0, and in Am, ambrisentan was orally administered the day after MCT injection for 4 weeks. The right ventricle (RV) pressure was measured and pathological changes of the lung tissues were observed by Victoria blue staining. Protein expressions of ET-1, ERA, endothelial nitric oxide synthase (eNOS) and NOX4 were confirmed by western blot analysis. RESULTS: Ambrisentan treatment resulted in a recovery of the body weight and RV/left ventricle+septum at week 4. The RV pressure was lowered at weeks 2 and 4 after ambrisentan administration. Medial wall thickening of pulmonary arterioles and the number of intra-acinar arteries were also attenuated by ambrisentan at week 4. Protein expression levels of ET-1 and eNOS were recovered at weeks 2 and 4, and ERA levels recovered at week 4. CONCLUSIONS: Ambrisentan administration resulted in the recovery of ET-1, ERA and eNOS protein expression levels in the PAH model. However, the expression level of NOX4 remained unaffected after ambrisentan treatment.


Subject(s)
Animals , Arteries , Arterioles , Blotting, Western , Body Weight , Endothelin Receptor Antagonists , Endothelins , Gene Expression , Heart Ventricles , Humans , Hypertension , Hypertension, Pulmonary , Lung , Models, Animal , Monocrotaline , NADP , NADPH Oxidases , Nitric Oxide Synthase Type III , Oxidoreductases , Rats , Receptors, Endothelin , Victoria
7.
Article in Chinese | WPRIM | ID: wpr-813021

ABSTRACT

Nicotinamide adenine dinucleotide phosphate oxidase (NOX) is a major source of reactive oxygen species (ROS) in the cardiovascular system. The family of NOX includes seven isoforms, and expressed in different cardiovascular cell types and cell compartments, modulating multiple functions, such as cell proliferation, migration, differentiation, apoptosis, senescence, and inflammatory responses. The NOX-derived ROS are involved in many processes associated with cardiovascular diseases, such as hypertension, atherosclerosis, diabetic vascular disease, ventricular remodeling after myocardial infarction, and so on.


Subject(s)
Cardiovascular Diseases , Humans , Hypertension , NADPH Oxidases , Oxidation-Reduction , Oxidative Stress , Reactive Oxygen Species
8.
Braz. j. biol ; 78(4): 686-690, Nov. 2018. graf
Article in English | LILACS | ID: biblio-951609

ABSTRACT

Abstract Kiwifruit are a popular fruit worldwide; however, plant growth is threatened by abiotic stresses such as drought and high temperatures. Niacin treatment in plants has been shown to increase NADPH levels, thus enhancing abiotic stresses tolerance. Here, we evaluate the effect of niacin solution spray treatment on NADPH levels in the kiwifruit cultivars Hayward and Xuxiang. We found that spray treatment with niacin solution promoted NADPH and NADP+ levels and decreased both O2·- production and H2O2 contents in leaves during a short period. In fruit, NADPH contents increased during early development, but decreased later. However, no effect on NADP+ levels has been observed throughout fruit development. In summary, this report suggests that niacin may be used to increase NADPH oxidases, thus increasing stress-tolerance in kiwifruit during encounter of short-term stressful conditions.


Resumo Kiwis são uma fruta popular em todo o mundo; No entanto, o crescimento das plantas é ameaçado por estresses abióticos como a seca e as altas temperaturas. O tratamento com niacina em plantas mostrou aumentar os níveis de NADPH, aumentando assim a tolerância a stress abiótico. Aqui, avaliamos o efeito do tratamento com spray de solução de niacina sobre os níveis de NADPH nos cultivares de kiwis Hayward e Xuxiang. Descobrimos que o tratamento por spray com solução de niacina promoveu níveis de NADPH e NADP + e diminuiu a produção de O2·- e os teores de H2O2 nas folhas durante um curto período. Nos frutos, os teores de NADPH aumentaram durante o desenvolvimento precoce, mas diminuíram mais tarde. No entanto, não se observou qualquer efeito nos níveis de NADP + ao longo do desenvolvimento do fruto. Em resumo, este relatório sugere que a niacina pode ser utilizada para aumentar NADPH oxidases, aumentando assim a tolerância ao estresse em kiwis durante o encontro de condições estressantes de curto prazo.


Subject(s)
NADPH Oxidases/drug effects , Actinidia/drug effects , Fruit/drug effects , Niacin/pharmacology , Oxidation-Reduction , Plant Leaves/drug effects , Plant Leaves/metabolism , Free Radicals/metabolism , Fruit/growth & development , NADP/metabolism
9.
Article in English | WPRIM | ID: wpr-773640

ABSTRACT

The aims of the present study were to evaluate the effects of puerarin on angiotensin II-induced cardiac fibroblast proliferation and to explore the molecular mechanisms of action. Considering the role of HO in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, we hypothesized that modulating catalase activity would be a potential target in regulating the redox-sensitive pathways. Our results showed that the activation of Rac1 was dependent on the levels of intracellular HO. Puerarin blocked the phosphorylation of extracellular regulated protein kinases (ERK)1/2, abolished activator protein (AP)-1 binding activity, and eventually attenuated cardiac fibroblast proliferation through the inhibition of HO-dependent Rac1 activation. Further studies revealed that angiotensin II treatment resulted in decreased catalase protein expression and enzyme activity, which was disrupted by puerarin via the upregulation of catalase protein expression at the transcriptional level and the prolonged protein degradation. These findings indicated that the anti-proliferation mechanism of puerarin was mainly through blocking angiontensin II-triggered downregulation of catalase expression and HO-dependent Rac1 activation.


Subject(s)
Angiotensin II , Pharmacology , Angiotensin II Type 1 Receptor Blockers , Pharmacology , Animals , Animals, Newborn , Catalase , Genetics , Metabolism , Cell Proliferation , Cells, Cultured , Extracellular Signal-Regulated MAP Kinases , Metabolism , Fibroblasts , Gene Expression Regulation , Heart , Hydrogen Peroxide , Metabolism , Pharmacology , Isoflavones , Pharmacology , Mice , Myocardium , Cell Biology , Metabolism , NADPH Oxidases , Metabolism , Neuropeptides , Metabolism , Signal Transduction , Transcription Factor AP-1 , Metabolism , Transcriptional Activation , rac1 GTP-Binding Protein , Metabolism
10.
Frontiers of Medicine ; (4): 518-524, 2018.
Article in English | WPRIM | ID: wpr-772734

ABSTRACT

The increased levels of intracellular reactive oxygen species (ROS) in granulosa cells (GCs) may affect the pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared the in vitro fertilization and embryo transfer (IVF-ET) results of 22 patients with PCOS and 25 patients with tubal factor infertility and detected the ROS levels in the GCs of these two groups. Results showed that the PCOS group had significantly larger follicles on the administration day for human chorionic gonadotropin than the tubal factor group (P 0.05). PCOS group had slightly lower fertilization, cleavage, grade I/II embryo, clinical pregnancy, and implantation rates and higher miscarriage rate than the tubal factor group (P > 0.05). We further found a significantly higher ROS level of GCs in the PCOS group than in the tubal factor group (P < 0.05). The increased ROS levels in GCs caused GC apoptosis, whereas NADPH oxidase 2 (NOX2) specific inhibitors (diphenyleneiodonium and apocynin) significantly reduced the ROS production in the PCOS group. In conclusion, the increased ROS expression levels in PCOS GCs greatly induced cell apoptosis, which further affected the oocyte quality and reduced the positive IVF-ET pregnancy results of women with PCOS. NADPH oxidase pathway may be involved in the mechanism of ROS production in GCs of women with PCOS.


Subject(s)
Abortion, Spontaneous , Epidemiology , Acetophenones , Therapeutic Uses , Adult , Apoptosis , Embryo Transfer , Female , Fertilization in Vitro , Granulosa Cells , Metabolism , Humans , NADPH Oxidases , Onium Compounds , Therapeutic Uses , Oocyte Retrieval , Oxidative Stress , Polycystic Ovary Syndrome , Drug Therapy , Pregnancy , Pregnancy Rate , Reactive Oxygen Species , Metabolism
11.
Article in English | WPRIM | ID: wpr-741595

ABSTRACT

An isoform of NADPH oxidase (NOX), NOX2 is a superoxide-generating enzyme involved in diverse pathophysiological events. Although its potential as a therapeutic target has been validated, there is no clinically available inhibitor. Herein, NOX2-inhibitory activity was screened with the constituents isolated from Schisandra chinensis, which has been reported to have antioxidant and reactive oxygen species (ROS)-scavenging effects. Among the partitions prepared from crude methanolic extract, a chloroform-soluble partition showed the highest NOX2-inhibitory activity in PLB-985 cell-based NOX2 assay. A total of twenty nine compounds (1 – 29) were identified from the chloroform fraction, including two first isolated compounds; dimethyl-malate (25) and 2-(2-hydroxyacetyl) furan (27) from this plants. Of these constituents, two compounds (gomisin T, and pregomisin) exhibited an NOX2-inhibitory effect with the IC₅₀ of 9.4 ± 3.6, and 62.9 ± 11.3 µM, respectively. They are confirmed not to be nonspecific superoxide scavengers in a counter assay using a xanthine-xanthine oxidase system. These findings suggest the potential application of gomisin T (6) and other constituents of S. chinensis to inhibit NOX2.


Subject(s)
Chloroform , Fruit , Lignans , Methanol , NADP , NADPH Oxidases , Oxidoreductases , Reactive Oxygen Species , Schisandra , Superoxides
12.
Mem. Inst. Oswaldo Cruz ; 113(6): e140421, 2018. graf
Article in English | LILACS | ID: biblio-894933

ABSTRACT

BACKGROUND Streptococcus agalactiae can causes sepsis, pneumonia, and meningitis in neonates, the elderly, and immunocompromised patients. Although the virulence properties of S. agalactiae have been partially elucidated, the molecular mechanisms related to reactive oxygen species (ROS) generation in infected human endothelial cells need further investigation. OBJECTIVES This study aimed to evaluate the influence of oxidative stress in human umbilical vein endothelial cells (HUVECs) during S. agalactiae infection. METHODS ROS production during S. agalactiae-HUVEC infection was detected using the probe CM-H2DCFDA. Microfilaments labelled with phalloidin-FITC and p47phox-Alexa 546 conjugated were analysed by immunofluorescence. mRNA levels of p47phox (NADPH oxidase subunit) were assessed using Real Time qRT-PCR. The adherence and intracellular viability of S. agalactiae in HUVECs with or without pre-treatment of DPI, apocynin (NADPH oxidase inhibitors), and LY294002 (PI3K inhibitor) were evaluated by penicillin/gentamicin exclusion. Phosphorylation of p47phox and Akt activation by S. agalactiae were evaluated by immunoblotting analysis. FINDINGS Data showed increased ROS production 15 min after HUVEC infection. Real-Time qRT-PCR and western blotting performed in HUVEC infected with S. agalactiae detected alterations in mRNA levels and activation of p47phox. Pre-treatment of endothelial cells with NADPH oxidase (DPI and apocynin) and PI3K/Akt pathway (LY294002) inhibitors reduced ROS production, bacterial intracellular viability, and generation of actin stress fibres in HUVECs infected with S. agalactiae. CONCLUSIONS ROS generation via the NADPH oxidase pathway contributes to invasion of S. agalactiae in human endothelial cells accompanied by cytoskeletal reorganisation through the PI3K/Akt pathway, which provides novel evidence for the involvement of oxidative stress in S. agalactiae pathogenesis.


Subject(s)
Humans , Reactive Oxygen Species/analysis , NADPH Oxidases/analysis , NADPH Oxidases/metabolism , Human Umbilical Vein Endothelial Cells/microbiology , Signal Transduction/physiology , Real-Time Polymerase Chain Reaction
13.
Article in English | WPRIM | ID: wpr-713576

ABSTRACT

Chalcone, (2E)-1,3-Diphenylprop-2-en-1-one, and its synthetic derivatives are known to possess anti-oxidative and anti-inflammatory properties. In the present study, we prepared a novel synthetic chalcone compound, (E)-1-(4-hydroxyphenyl)-3-(2-(trifluoromethoxy)phenyl)prop-2-en-1-one name (YJI-7), and investigated its inhibitory effects on endotoxin-stimulated production of reactive oxygen species (ROS) and expression of inflammatory mediators in macrophages. We demonstrated that treatment of RAW 264.7 macrophages with YJI-7 significantly suppressed lipopolysaccharide (LPS)-stimulated ROS production. We also found that YJI-7 substantially decreased NADPH oxidase activity stimulated by LPS, indicating that YJI-7 regulates ROS production via modulation of NADPH oxidase in macrophages. Furthermore, YJI-7 strongly inhibited the expression of a number of inflammatory mediators in a gene-selective manner, suggesting that YJI-7 possesses potent anti-inflammatory properties, as well as anti-oxidative activity. In continuing experiments to investigate the mechanisms that could underlie such biological effects, we revealed that YJI-7 suppressed phosphorylation of p38MAPK and JNK stimulated by LPS, whereas no significant effect on ERK was observed. Furthermore, LPS-stimulated production of ROS, activation of NADPH oxidase and expression of inflammatory mediators were markedly suppressed by treatment with selective inhibitor of p38MAPK (SB203580) and JNK (SP600125). Taken together, these results demonstrated that YJI-7, a novel synthetic chalcone derivative, suppressed LPS-stimulated ROS production via modulation of NADPH oxidase and diminished expression of inflammatory mediators, at least in part, via down-regulation of p38MAPK and JNK signaling in macrophages.


Subject(s)
Chalcone , Down-Regulation , Macrophages , NADPH Oxidases , Phosphorylation , Reactive Oxygen Species
14.
Article in English | WPRIM | ID: wpr-713541

ABSTRACT

BACKGROUND/AIMS: NADPH (nicotinamide adenine dinucleotide phosphate) oxidase (NOX)-mediated oxidative stress plays a key role in promotion of oxidative injury in the cardiovascular system. The aim of this study is to evaluate the status of NOX in endothelial progenitor cells (EPCs) of hyperlipidemic patients and to assess the correlation between NOX activity and the functions EPCs. METHODS: A total of 30 hyperlipidemic patients were enrolled for this study and 30 age-matched volunteers with normal level of plasma lipids served as controls. After the circulating EPCs were isolated, the EPC functions (migration, adhesion and tube formation) were evaluated and the status of NOX (expression and activity) was examined. RESULTS: Compared to the controls, hyperlipidemic patients showed an increase in plasma lipids and a reduction in EPC functions including the attenuated abilities in adhesion, migration and tube formation, concomitant with an increase in NOX expression (NOX2 and NOX4), NOX activity, and reactive oxygen species production. The data analysis showed negative correlations between NOX activity and EPC functions. CONCLUSIONS: There is a positive correlation between the NOX-mediated oxidative stress and the dysfunctions of circulating EPCs in hyperlipidemic patients, and suppression of NOX might offer a novel strategy to improve EPCs functions in hyperlipidemia.


Subject(s)
Adenine , Cardiovascular System , Endothelial Progenitor Cells , Humans , Hyperlipidemias , NADP , NADPH Oxidases , Oxidative Stress , Oxidoreductases , Plasma , Reactive Oxygen Species , Statistics as Topic , Volunteers
15.
Yonsei Medical Journal ; : 366-375, 2018.
Article in English | WPRIM | ID: wpr-714674

ABSTRACT

PURPOSE: Vascular smooth muscle cell (VSMC) proliferation induced by native low-density lipoprotein (nLDL) stimulation is dependent on superoxide production from activated NADPH oxidase. The present study aimed to investigate whether the novel arginase inhibitor limonin could suppress nLDL-induced VSMC proliferation and to examine related mechanisms. MATERIALS AND METHODS: Isolated VSMCs from rat aortas were treated with nLDL, and cell proliferation was measured by WST-1 and BrdU assays. NADPH oxidase activation was evaluated by lucigenin-induced chemiluminescence, and phosphorylation of protein kinase C (PKC) βII and extracellular signal-regulated kinase (ERK) 1/2 was determined by western blot analysis. Mitochondrial reactive oxygen species (ROS) generation was assessed using MitoSOX-red, and intracellular L-arginine concentrations were determined by high-performance liquid chromatography (HPLC) in the presence or absence of limonin. RESULTS: Limonin inhibited arginase I and II activity in the uncompetitive mode, and prevented nLDL-induced VSMC proliferation in a p21Waf1/Cip1-dependent manner without affecting arginase protein levels. Limonin blocked PKCβII phosphorylation, but not ERK1/2 phosphorylation, and translocation of p47phox to the membrane was decreased, as was superoxide production in nLDL-stimulated VSMCs. Moreover, mitochondrial ROS generation was increased by nLDL stimulation and blocked by preincubation with limonin. Mitochondrial ROS production was responsible for the phosphorylation of PKCβII. HPLC analysis showed that arginase inhibition with limonin increases intracellular L-arginine concentrations, but decreases polyamine concentrations. L-Arginine treatment prevented PKCβII phosphorylation without affecting ERK1/2 phosphorylation. CONCLUSION: Increased L-arginine levels following limonin-dependent arginase inhibition prohibited NADPH oxidase activation in a PKCβII-dependent manner, and blocked nLDL-stimulated VSMC proliferation.


Subject(s)
Animals , Aorta , Arginase , Arginine , Blotting, Western , Bromodeoxyuridine , Cell Proliferation , Chromatography, High Pressure Liquid , Chromatography, Liquid , Lipoproteins , Luminescence , Membranes , Muscle, Smooth, Vascular , NADP , NADPH Oxidases , Phosphorylation , Phosphotransferases , Protein Kinase C , Rats , Reactive Oxygen Species , Superoxides
16.
Article in English | WPRIM | ID: wpr-716768

ABSTRACT

PURPOSE: Abnormal potassium channels expression affects vessel function, including vascular tone and proliferation rate. Diverse potassium channels, including voltage-gated potassium (Kv) channels, are involved in pathological changes of pulmonary arterial hypertension (PAH). Since the role of the Kv1.7 channel in PAH has not been previously studied, we investigated whether Kv1.7 channel expression changes in the lung tissue of a monocrotaline (MCT)-induced PAH rat model and whether this change is influenced by the endothelin (ET)-1 and reactive oxygen species (ROS) pathways. METHODS: Rats were separated into 2 groups: the control (C) group and the MCT (M) group (60 mg/kg MCT). A hemodynamic study was performed by catheterization into the external jugular vein to estimate the right ventricular pressure (RVP), and pathological changes in the lung tissue were investigated. Changes in protein and mRNA levels were confirmed by western blot and polymerase chain reaction analysis, respectively. RESULTS: MCT caused increased RVP, medial wall thickening of the pulmonary arterioles, and increased expression level of ET-1, ET receptor A, and NADPH oxidase (NOX) 4 proteins. Decreased Kv1.7 channel expression was detected in the lung tissue. Inward-rectifier channel 6.1 expression in the lung tissue also increased. We confirmed that ET-1 increased NOX4 level and decreased glutathione peroxidase-1 level in pulmonary artery smooth muscle cells (PASMCs). ET-1 increased ROS level in PASMCs. CONCLUSION: Decreased Kv1.7 channel expression might be caused by the ET-1 and ROS pathways and contributes to MCT-induced PAH.


Subject(s)
Animals , Arterioles , Blotting, Western , Catheterization , Catheters , Endothelins , Glutathione , Hemodynamics , Hypertension , Jugular Veins , Lung , Models, Animal , Monocrotaline , Myocytes, Smooth Muscle , NADPH Oxidases , Polymerase Chain Reaction , Potassium , Potassium Channels , Potassium Channels, Voltage-Gated , Pulmonary Artery , Rats , Reactive Oxygen Species , RNA, Messenger , Ventricular Pressure
17.
Chonnam Medical Journal ; : 159-166, 2018.
Article in English | WPRIM | ID: wpr-716580

ABSTRACT

The Amyloid β peptide (Aβ) is a main component of senile plaques in Alzheimer's disease. Currently, NADPH oxidase (NOX) and mitochondria are considered as primary sources of ROS induced by Aβ. However, the contribution of NOX and mitochondria to Aβ-induced ROS generation has not been well defined. To delineate the relative involvement of NOX and mitochondria in Aβ-induced ROS generation and neuronal death in mouse cortical cultures, we examined the effect of NOX inhibitors, apocynin and AEBSF, and the mitochondria-targeted antioxidants (MTAs), mitotempol and mitoquinone, on Aβ-induced ROS generation and neuronal deaths. Cell death was assessed by measuring lactate dehydrogenase efflux in bathing media at 24 and 48 hrs after exposure to Aβ₁₋₄₂. Aβ₁₋₄₂ induced dose- and time-dependent neuronal deaths in cortical cultures. Treatment with 20 µM Aβ₁₋₄₂ markedly and continuously increased not only the DHE fluorescence (intracellular ROS signal), but also the DHR123 fluorescence (mitochondrial ROS signal) up to 8 hrs. Treatment with apocynin or AEBSF selectively suppressed the increase in DHE fluorescence, while treatment with mitotempol selectively suppressed the increase in DHR123 fluorescence. Each treatment with apocynin, AEBSF, mitotempol or mitoquinone significantly attenuated the Aβ₁₋₄₂-induced neuronal deaths. However, any combined treatment with apocynin/AEBSF and mitotempol/mitoquinone failed to show additive effects. These findings indicate that 20 µM Aβ₁₋₄₂ induces oxidative neuronal death via inducing mitochondrial ROS as well as NOX activation in mixed cortical cultures, but combined suppression of intracellular and mitochondrial ROS generation fail to show any additive neuroprotective effects against Aβ neurotoxicity.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Amyloid , Animals , Antioxidants , Baths , Cell Death , Fluorescence , L-Lactate Dehydrogenase , Mice , Mitochondria , NADP , NADPH Oxidases , Neurons , Neuroprotective Agents , Oxidative Stress , Plaque, Amyloid
18.
Article in English | WPRIM | ID: wpr-812430

ABSTRACT

The aims of the present study were to evaluate the effects of puerarin on angiotensin II-induced cardiac fibroblast proliferation and to explore the molecular mechanisms of action. Considering the role of HO in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, we hypothesized that modulating catalase activity would be a potential target in regulating the redox-sensitive pathways. Our results showed that the activation of Rac1 was dependent on the levels of intracellular HO. Puerarin blocked the phosphorylation of extracellular regulated protein kinases (ERK)1/2, abolished activator protein (AP)-1 binding activity, and eventually attenuated cardiac fibroblast proliferation through the inhibition of HO-dependent Rac1 activation. Further studies revealed that angiotensin II treatment resulted in decreased catalase protein expression and enzyme activity, which was disrupted by puerarin via the upregulation of catalase protein expression at the transcriptional level and the prolonged protein degradation. These findings indicated that the anti-proliferation mechanism of puerarin was mainly through blocking angiontensin II-triggered downregulation of catalase expression and HO-dependent Rac1 activation.


Subject(s)
Angiotensin II , Pharmacology , Angiotensin II Type 1 Receptor Blockers , Pharmacology , Animals , Animals, Newborn , Catalase , Genetics , Metabolism , Cell Proliferation , Cells, Cultured , Extracellular Signal-Regulated MAP Kinases , Metabolism , Fibroblasts , Gene Expression Regulation , Heart , Hydrogen Peroxide , Metabolism , Pharmacology , Isoflavones , Pharmacology , Mice , Myocardium , Cell Biology , Metabolism , NADPH Oxidases , Metabolism , Neuropeptides , Metabolism , Signal Transduction , Transcription Factor AP-1 , Metabolism , Transcriptional Activation , rac1 GTP-Binding Protein , Metabolism
19.
Acta cir. bras ; 32(11): 913-923, Nov. 2017. tab, graf
Article in English | LILACS | ID: biblio-886181

ABSTRACT

Abstract Purpose: To investigate the effects of hyperbaric oxygenation (HBO) on intestinal ischemia and reperfusion (IR) injury, we evaluated the expression of 84 genes related to oxidative stress and the antioxidant response in mouse hearts. Methods: Four groups were subjected to 60 minutes of intestinal ischemia followed by 60 minutes of reperfusion: IRG, ischemia and reperfusion group without HBO; HBO-IG, which received HBO during ischemia; HBO-RG, which received HBO during reperfusion; and HBO-IRG, which received HBO during ischemia and reperfusion. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes. The (RT-qPCR) method was applied. Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student's t-test p<0.05). Results: Eight genes (9.52%) were hyperexpressed in the IRG. When the HBO groups were compared to the IRG, we found a decrease in the expression of eight genes in the HBO-IG, five genes in the HBO-RG, and seven genes in the HBO-IRG. Conclusion: The reduction in the expression of genes related to oxidative stress and antioxidant defense following HBO in mouse hearts resulting from intestinal IR injury was more favorable during the ischemic period than during the reperfusion period.


Subject(s)
Animals , Male , Mice , Reperfusion Injury/prevention & control , Gene Expression , Oxidative Stress/genetics , Hyperbaric Oxygenation/methods , Intestines/blood supply , Reperfusion Injury/metabolism , Polymerase Chain Reaction , Oxidative Stress/drug effects , NADPH Oxidases/metabolism , Coronary Vessels/enzymology , Disease Models, Animal , Heart , Heart Diseases , Ischemia/metabolism , Mice, Inbred C57BL , Antioxidants/metabolism , Antioxidants/pharmacology
20.
Pesqui. vet. bras ; 37(4): 331-338, Apr. 2017. tab, graf
Article in English | ID: biblio-895411

ABSTRACT

The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8µg/ml for doxycycline, >4µg/ml for valnemulin, 8µg/ml for tiamulin, 32µg/ml for tylvalosin, >64µg/ml for lincomycin and >128µg/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.(AU)


Os objetivos deste trabalho foram a caracterização de isolados de Brachyspira hyodysenteriae e avaliar os padrões de sensibilidade antimicrobiana de isolados obtidos a partir de suínos no Brasil com base no teste de concentração inibitória mínima (MIC). A MIC foi realizada em 22 isolados de B. hyodysenteriae obtidos entre 2011 a 2013 usando os seguintes antimicrobianos: tilosina, tiamulina, valnemulina, doxiciclina, lincomicina e tilvalosina. Surtos de disenteria suína foram diagnosticados com base na apresentação clínica, isolamento bacteriano, lesões macroscópicas e microscópicas, PCR duplex para B. hyodysenteriae e B. pilosicoli e sequenciamento do gene nox. Todos os valores de MIC obtidos foram consistentemente mais elevados ou igual ao ponto de corte microbiológica descrito na literatura. Os valores de MIC 90 para os fármacos testados foram de 8 µg / mL para a doxiciclina, > 4 µg/ml de valnemulina, 8 µg / mL para a tiamulina, 32 µg / ml para tilvalosina, > 64 µg / ml para a lincomicina e > 128 µg / ml de tilosina. Estes resultados corroboram em grande parte com os relatados na literatura. Tiamulina, doxiciclina e tilvalosina apresentaram os menores resultados de MIC. Todas as amostras submetidas à análise filogenética com base na sequência do gene nox exibiram resultados semelhantes, indicando 100% de identidade com B. hyodysenteriae. Este é o primeiro estudo que descreve o padrão MIC de B. hyodysenteriae isoladas no Brasil.(AU)


Subject(s)
Microbial Sensitivity Tests/veterinary , Brachyspira hyodysenteriae/isolation & purification , NADPH Oxidases , Polymerase Chain Reaction/veterinary , Dysentery/veterinary
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