Nitric Oxide Overproduction by cue1 Mutants Differs on Developmental Stages and Growth Conditions

The cue1 nitric oxide (NO) overproducer mutants are impaired in a plastid phosphoenolpyruvate/phosphate translocator, mainly expressed in Arabidopsis thaliana roots. cue1 mutants present an increased content of arginine, a precursor of NO in oxidative synthesis processes. However, the pathways of plant NO biosynthesis and signaling have not yet been fully characterized, and the role of CUE1 in these processes is not clear. Here, in an attempt to advance our knowledge regarding NO homeostasis, we performed a deep characterization of the NO production of four different cue1 alleles (cue1-1, cue1-5, cue1-6 and nox1) during seed germination, primary root elongation, and salt stress resistance. Furthermore, we analyzed the production of NO in different carbon sources to improve our understanding of the interplay between carbon metabolism and NO homeostasis. After in vivo NO imaging and spectrofluorometric quantification of the endogenous NO levels of cue1 mutants, we demonstrate that CUE1 does not directly contribute to the rapid NO synthesis during seed imbibition. Although cue1 mutants do not overproduce NO during germination and early plant development, they are able to accumulate NO after the seedling is completely established. Thus, CUE1 regulates NO homeostasis during post-germinative growth to modulate root development in response to carbon metabolism, as different sugars modify root elongation and meristem organization in cue1 mutants. Therefore, cue1 mutants are a useful tool to study the physiological effects of NO in post-germinative growth.

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Involvement of Nitric Oxide in Iodine Deficiency-Induced Microvascular Remodeling in the Thyroid Gland: Role of Nitric Oxide Synthase 3 and Ryanodine Receptors

Endocrinology ◽

10.1210/en.2014-1729 ◽

2014 ◽

Vol 156 (2) ◽

pp. 707-720 ◽

Cited By ~ 13

Author(s):

J. Craps ◽

C. Wilvers ◽

V. Joris ◽

B. De Jongh ◽

J. Vanderstraeten ◽

...

Keyword(s):

Nitric Oxide ◽

Blood Flow ◽

Thyroid Gland ◽

Mrna Expression ◽

Iodine Deficiency ◽

Ryanodine Receptors ◽

No Production

Iodine deficiency (ID) induces microvascular changes in the thyroid gland via a TSH-independent reactive oxygen species-hypoxia inducible factor (HIF)-1α-vascular endothelial growth factor (VEGF) pathway. The involvement of nitric oxide (NO) in this pathway and the role of calcium (Ca2+) and of ryanodine receptors (RYRs) in NO synthase 3 (NOS3) activation were investigated in a murine model of goitrogenesis and in 3 in vitro models of ID, including primary cultures of human thyrocytes. ID activated NOS3 and the production of NO in thyrocytes in vitro and increased the thyroid blood flow in vivo. Using bevacizumab (a blocking antibody against VEGF-A) in mice, it appeared that NOS3 is activated upstream of VEGF-A. L-nitroarginine methyl ester (a NOS inhibitor) blocked the ID-induced increase in thyroid blood flow in vivo and NO production in vitro, as well as ID-induced VEGF-A mRNA and HIF-1α expression in vitro, whereas S-nitroso-acetyl-penicillamine (a NO donor) did the opposite. Ca2+ is involved in this pathway as intracellular Ca2+ flux increased after ID, and thapsigargin activated NOS3 and increased VEGF-A mRNA expression. Two of the 3 known mammalian RYR isoforms (RYR1 and RYR2) were shown to be expressed in thyrocytes. RYR inhibition using ryanodine at 10μM decreased ID-induced NOS3 activation, HIF-1α, and VEGF-A expression, whereas RYR activation with ryanodine at 1nM increased NOS3 activation and VEGF-A mRNA expression. In conclusion, during the early phase of TSH-independent ID-induced microvascular activation, ID sequentially activates RYRs and NOS3, thereby supporting ID-induced activation of the NO/HIF-1α/VEGF-A pathway in thyrocytes.

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Nitric oxide mediation of chemoregulation but not autoregulation of cerebral blood flow in primates

Journal of Neurosurgery ◽

10.3171/jns.1996.84.1.0071 ◽

1996 ◽

Vol 84 (1) ◽

pp. 71-78 ◽

Cited By ~ 80

Author(s):

B. Gregory Thompson ◽

Ryszard M. Pluta ◽

Mary E. Girton ◽

Edward H. Oldfield

Keyword(s):

Nitric Oxide ◽

Blood Flow ◽

Cerebral Blood Flow ◽

No Production ◽

Direct Role ◽

Content Type ◽

Continuous Release ◽

Fine Print

✓ The authors sought to develop a model for assessing in vivo regulation of cerebral vasoregulation by nitric oxide (NO), originally described as endothelial-derived relaxing factor, and to use this model to establish the role of NO in the regulation of cerebral blood flow (CBF) in primates. By using regional intraarterial perfusion, the function of NO in cerebral vasoregulation was examined without producing confounding systemic physiological effects. Issues examined were: whether resting vasomotor tone requires NO; whether NO mediates vasodilation during chemoregulation and autoregulation of CBF; and whether there is a relationship between the degree of hypercapnia and hypotension and NO production. Twelve anesthetized (0.5% isoflurane) cynomolgus monkeys were monitored continuously for cortical CBF, PaCO2, and mean arterial pressure (MAP), which were systematically altered to provide control and experimental curves of chemoregulation (CBF vs. PaCO2) and autoregulation (CBF vs. MAP) during continuous intracarotid infusion of 1) saline and 2) an NO synthase inhibitor (NOSI), either l-n-monomethyl arginine or nitro l-arginine. During basal conditions (PaCO2 of 38–42 mm Hg) NOSI infusion of internal carotid artery (ICA) reduced cortical CBF from 62 (saline) to 53 ml/100 g/per minute (p < 0.01), although there was no effect on MAP. Increased CBF in response to hypercapnia was completely blocked by ICA NOSI. The difference in regional (r)CBF between ICA saline and NOSI infusion increased linearly with PaCO2 when PaCO2 was greater than 40 mm Hg, indicating a graded relationship of NO production, increasing PaCO2, and increasing CBF. Diminution of CBF with NOSI infusion was reversed by simultaneous ICA infusion of l-arginine, indicating a direct role of NO synthesis in the chemoregulation of CBF. Hypotension and hypertension were induced with trimethaphan camsylate (Arfonad) and phenylephrine at constant PaCO2 (40 ± 1 mm Hg). Autoregulation in response to changes in MAP from 50 to 140 mm Hg was unaffected by ICA infusion of NOSI. In primates, cerebral vascular tone is modulated in vivo by NO; continuous release of NO is necessary to maintain homeostatic cerebral vasodilation; vasodilation during chemoregulation of CBF is mediated directly by NO production; autoregulatory vasodilation with hypotension is not mediated by NO; and increasing PaCO2 induces increased NO production.

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RAP2.3 negatively regulates nitric oxide biosynthesis and related responses through a rheostat-like mechanism in Arabidopsis

Journal of Experimental Botany ◽

10.1093/jxb/eraa069 ◽

2020 ◽

Vol 71 (10) ◽

pp. 3157-3171 ◽

Cited By ~ 2

Author(s):

José León ◽

Álvaro Costa-Broseta ◽

Mari Cruz Castillo

Keyword(s):

Nitric Oxide ◽

Root Elongation ◽

Guard Cells ◽

No Production ◽

Aba Signaling ◽

Inhibition Of Growth ◽

Genome Wide ◽

Molecular Rheostat ◽

No Signaling

Abstract Nitric oxide (NO) is sensed through a mechanism involving the degradation of group-VII ERF transcription factors (ERFVIIs) that is mediated by the N-degron pathway. However, the mechanisms regulating NO homeostasis and downstream responses remain mostly unknown. To explore the role of ERFVIIs in regulating NO production and signaling, genome-wide transcriptome analyses were performed on single and multiple erfvii mutants of Arabidopsis following exposure to NO. Transgenic plants overexpressing degradable or non-degradable versions of RAP2.3, one of the five ERFVIIs, were also examined. Enhanced RAP2.3 expression attenuated the changes in the transcriptome upon exposure to NO, and thereby acted as a brake for NO-triggered responses that included the activation of jasmonate and ABA signaling. The expression of non-degradable RAP2.3 attenuated NO biosynthesis in shoots but not in roots, and released the NO-triggered inhibition of hypocotyl and root elongation. In the guard cells of stomata, the control of NO accumulation depended on PRT6-triggered degradation of RAP2.3 more than on RAP2.3 levels. RAP2.3 therefore seemed to work as a molecular rheostat controlling NO homeostasis and signaling. Its function as a brake for NO signaling was released upon NO-triggered PRT6-mediated degradation, thus allowing the inhibition of growth, and the potentiation of jasmonate- and ABA-related signaling.

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Plant Nitric Oxide Signaling under Drought Stress

Plants ◽

10.3390/plants10020360 ◽

2021 ◽

Vol 10 (2) ◽

pp. 360

Author(s):

Su-Ee Lau ◽

Mohd Fadhli Hamdan ◽

Teen-Lee Pua ◽

Noor Baity Saidi ◽

Boon Chin Tan

Keyword(s):

Nitric Oxide ◽

Abiotic Stress ◽

Drought Stress ◽

Higher Plants ◽

Genetic Manipulation ◽

Growth Conditions ◽

No Production ◽

Stress Signaling ◽

Nitric Oxide Signaling

Water deficit caused by drought is a significant threat to crop growth and production. Nitric oxide (NO), a water- and lipid-soluble free radical, plays an important role in cytoprotection. Apart from a few studies supporting the role of NO in drought responses, little is known about this pivotal molecular amendment in the regulation of abiotic stress signaling. In this review, we highlight the knowledge gaps in NO roles under drought stress and the technical challenges underlying NO detection and measurements, and we provide recommendations regarding potential avenues for future investigation. The modulation of NO production to alleviate abiotic stress disturbances in higher plants highlights the potential of genetic manipulation to influence NO metabolism as a tool with which plant fitness can be improved under adverse growth conditions.

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Plant Nitric Oxide Signaling under Drought Stress

10.20944/preprints202101.0616.v1 ◽

2021 ◽

Author(s):

Su-Ee Lau ◽

Mohd Fadhli Hamdan ◽

Teen-Lee Pua ◽

Noor Baity Saidi ◽

Boon Chin Tan

Keyword(s):

Nitric Oxide ◽

Abiotic Stress ◽

Drought Stress ◽

Higher Plants ◽

Genetic Manipulation ◽

Growth Conditions ◽

No Production ◽

Stress Signaling ◽

Nitric Oxide Signaling

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l-Arginine Availability Modulates Local Nitric Oxide Production and Parasite Killing in Experimental Trypanosomiasis

Infection and Immunity ◽

10.1128/iai.68.8.4653-4657.2000 ◽

2000 ◽

Vol 68 (8) ◽

pp. 4653-4657 ◽

Cited By ~ 113

Author(s):

Alain P. Gobert ◽

Sylvie Daulouede ◽

Michel Lepoivre ◽

Jean Luc Boucher ◽

Bernard Bouteille ◽

...

Keyword(s):

Nitric Oxide ◽

Peritoneal Macrophages ◽

No Production ◽

Nitrite Production ◽

Common Substrate ◽

Nos Inhibitor

ABSTRACT Nitric oxide (NO) is an important effector molecule of the immune system in eliminating numerous pathogens. Peritoneal macrophages fromTrypanosoma brucei brucei-infected mice express type II NO synthase (NOS-II), produce NO, and kill parasites in the presence ofl-arginine in vitro. Nevertheless, parasites proliferate in the vicinity of these macrophages in vivo. The present study shows thatl-arginine availability modulates NO production. Trypanosomes use l-arginine for polyamine synthesis, required for DNA and trypanothione synthesis. Moreover, arginase activity is up-regulated in macrophages from infected mice from the first days of infection. Arginase competes with NOS-II for their common substrate, l-arginine. In vitro, arginase inhibitors decreased urea production, increased macrophage nitrite production, and restored trypanosome killing. In vivo, a dramatic decrease inl-arginine concentration was observed in plasma from infected mice. In situ restoration of NO production and trypanosome killing were observed when excess l-arginine, but notd-arginine or l-arginine plusN ω-nitro-l-arginine (a NOS inhibitor), was injected into the peritoneum of infected mice. These data indicate the role of l-arginine depletion, induced by arginase and parasites, in modulating the l-arginine–NO pathway under pathophysiological conditions.

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The Signaling Pathways in Nitric Oxide Production by Neutrophils Exposed to N-nitrosodimethylamine

Letters in Drug Design & Discovery ◽

10.2174/1570180815666180426121503 ◽

2018 ◽

Vol 16 (2) ◽

pp. 194-199

Author(s):

Wioletta Ratajczak-Wrona ◽

Ewa Jablonska

Keyword(s):

Nitric Oxide ◽

Signaling Pathways ◽

Molecular Mechanisms ◽

Polymorphonuclear Neutrophils ◽

Microbial Pathogens ◽

Human Neutrophils ◽

No Production ◽

Oxide Synthase ◽

Inducible Nitric Oxide

Background: Polymorphonuclear neutrophils (PMNs) play a crucial role in the innate immune system’s response to microbial pathogens through the release of reactive nitrogen species, including Nitric Oxide (NO). </P><P> Methods: In neutrophils, NO is produced by the inducible Nitric Oxide Synthase (iNOS), which is regulated by various signaling pathways and transcription factors. N-nitrosodimethylamine (NDMA), a potential human carcinogen, affects immune cells. NDMA plays a major part in the growing incidence of cancers. Thanks to the increasing knowledge on the toxicological role of NDMA, the environmental factors that condition the exposure to this compound, especially its precursors- nitrates arouse wide concern. Results: In this article, we present a detailed summary of the molecular mechanisms of NDMA’s effect on the iNOS-dependent NO production in human neutrophils. Conclusion: This research contributes to a more complete understanding of the mechanisms that explain the changes that occur during nonspecific cellular responses to NDMA toxicity.

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Vasculoprotective Role of Inducible Nitric Oxide Synthase at Inflammatory Coronary Lesions Induced by Chronic Treatment With Interleukin-1β in Pigs in Vivo

Circulation ◽

10.1161/01.cir.96.9.3104 ◽

1997 ◽

Vol 96 (9) ◽

pp. 3104-3111 ◽

Cited By ~ 27

Author(s):

Yoshihiro Fukumoto ◽

Hiroaki Shimokawa ◽

Toshiyuki Kozai ◽

Toshiaki Kadokami ◽

Kouichi Kuwata ◽

...

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Inducible Nitric Oxide Synthase ◽

Chronic Treatment ◽

Interleukin 1Β ◽

Coronary Lesions ◽

Oxide Synthase ◽

Inducible Nitric Oxide

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Phaseolin Attenuates Lipopolysaccharide-Induced Inflammation in RAW 264.7 Cells and Zebrafish

Biomedicines ◽

10.3390/biomedicines9040420 ◽

2021 ◽

Vol 9 (4) ◽

pp. 420

Author(s):

Su-Jung Hwang ◽

Ye-Seul Song ◽

Hyo-Jong Lee

Keyword(s):

Nitric Oxide ◽

Nuclear Translocation ◽

Raw 264.7 Cells ◽

Network Pharmacology ◽

Raw 264.7 ◽

Dependent Manner ◽

Bioactive Constituents

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.

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Novel Insights on the Role of Nitric Oxide in the Ovary: A Review of the Literature

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18030980 ◽

2021 ◽

Vol 18 (3) ◽

pp. 980

Author(s):

Maria Cristina Budani ◽

Gian Mario Tiboni

Keyword(s):

Nitric Oxide ◽

In Vivo Studies ◽

Published Data ◽

Vitro Fertilization ◽

Peripheral Neurons ◽

Relevant Role ◽

Oocyte Meiotic Maturation

Nitric oxide (NO) is formed during the oxidation of L-arginine to L-citrulline by the action of multiple isoenzymes of NO synthase (NOS): neuronal NOS (nNOS), endotelial NOS (eNOS), and inducible NOS (iNOS). NO plays a relevant role in the vascular endothelium, in central and peripheral neurons, and in immunity and inflammatory systems. In addition, several authors showed a consistent contribution of NO to different aspects of the reproductive physiology. The aim of the present review is to analyse the published data on the role of NO within the ovary. It has been demonstrated that the multiple isoenzymes of NOS are expressed and localized in the ovary of different species. More to the point, a consistent role was ascribed to NO in the processes of steroidogenesis, folliculogenesis, and oocyte meiotic maturation in in vitro and in vivo studies using animal models. Unfortunately, there are few nitric oxide data for humans; there are preliminary data on the implication of nitric oxide for oocyte/embryo quality and in-vitro fertilization/embryo transfer (IVF/ET) parameters. NO plays a remarkable role in the ovary, but more investigation is needed, in particular in the context of human ovarian physiology.

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