Nitric oxide chemistry and cellular signaling

Gow, Andrew J.; Ischiropoulos, Harry

doi:10.1002/jcp.1085

Cited by 139 publications

(94 citation statements)

References 67 publications

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“…Cells were counted by trypan blue exclusion following assay completion, and data were normalized as nitrite produced/h/1 ϫ 10 6 cells. In a separate experiment, in vitro AS activity was assayed by measuring conversion of [ 3 39 Ci/mmol) was used. Whole cell lysates were prepared by lysing the cells in 10 mM Tris-HCl containing protease inhibitors, 0.5 mM citrulline, and 0.5 mM aspartate followed by three cycles of freeze-thaw in a dry ice ethanol bath.…”

Section: Rna Isolation and Quantitative Reverse Transcriptase (Rt)-pcr-mentioning

confidence: 99%

“…Nitric oxide (NO) 1 is an important modulator for a wide range of functions including vasodilation of blood vessels, immune system function, angiogenesis, inhibition of leukocyte adhesion and platelet aggregation, gene regulation, and apoptosis (1)(2)(3). Moreover, NO has a dual role in cell viability depending on the tissue type and concentration.…”

mentioning

confidence: 99%

“…Although the expression of AS and AL in the liver is high, both enzymes are found in most mammalian tissues, although at significantly lower levels. The discovery of arginine-derived NO, catalyzed by nitric-oxide synthases (NOSs), revealed a second role for AS and AL (1)(2)(3). Together with NOS, they function as part of a citrulline-NO cycle where AS and AL convert citrulline to arginine, which is then oxidized to form NO and citrulline by NOS.…”

mentioning

confidence: 99%

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Argininosuccinate Synthase Expression Is Required to Maintain Nitric Oxide Production and Cell Viability in Aortic Endothelial Cells

Goodwin

Solomonson

Eichler

2004

Journal of Biological Chemistry

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Although cellular levels of arginine greatly exceed the apparent K m for endothelial nitric-oxide synthase, current evidence suggests that the bulk of this arginine may not be available for nitric oxide (NO) production. We propose that arginine regeneration, that is the recycling of citrulline back to arginine, defines the essential source of arginine for NO production. To support this proposal, RNA interference analysis was used to selectively reduce the expression of argininosuccinate synthase (AS), because the only known metabolic role for AS in endothelial cells is in the regeneration of L-arginine from L-citrulline. Western blot analysis demonstrated a significant and dose-dependent reduction of AS protein as a result of AS small interfering RNA treatment with a corresponding diminished capacity to produce basal or stimulated levels of NO, despite saturating levels of arginine in the medium. Unanticipated, however, was the finding that the viability of AS small interfering RNA-treated endothelial cells was significantly decreased when compared with control cells. Trypan blue exclusion analysis suggested that the loss of viability was not because of necrosis. Two indicators, reduced expression of Bcl-2 and an increase in caspase activity, which correlated directly with reduced expression of AS, suggested that the loss of viability was because of apoptosis. The exposure of cells to an NO donor prevented apoptosis associated with reduced AS expression. Overall, these results demonstrate the essential role of AS for endothelial NO production and cell viability.Nitric oxide (NO) 1 is an important modulator for a wide range of functions including vasodilation of blood vessels, immune system function, angiogenesis, inhibition of leukocyte adhesion and platelet aggregation, gene regulation, and apoptosis (1-3). Moreover, NO has a dual role in cell viability depending on the tissue type and concentration. Either very high or very low concentrations of NO may induce cell death, whereas basal concentrations may inhibit apoptosis (4 -7). Previous work has shown that NO protects against serum starvation-(8), H 2 O 2 -(9), TNF-␣-(10), and oxidized low density lipoprotein-induced apoptosis (11, 12) in endothelial cells.Argininosuccinate synthase (AS), the rate-limiting step (13) in the regeneration of arginine from citrulline, catalyzes the synthesis of argininosuccinate, AMP, and inorganic pyrophosphate from citrulline, ATP, and aspartate. Argininosuccinate is then cleaved by argininosuccinate lyase (AL) to produce Larginine and fumarate. In the liver, AS and AL function together as components of the urea cycle, ultimately to form arginine from citrulline. Although the expression of AS and AL in the liver is high, both enzymes are found in most mammalian tissues, although at significantly lower levels. The discovery of arginine-derived NO, catalyzed by nitric-oxide synthases (NOSs), revealed a second role for AS and AL (1-3). Together with NOS, they function as part of a citrulline-NO cycle where AS and AL convert citrul...

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Section: Rna Isolation and Quantitative Reverse Transcriptase (Rt)-pcr-mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

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Argininosuccinate Synthase Expression Is Required to Maintain Nitric Oxide Production and Cell Viability in Aortic Endothelial Cells

Goodwin

Solomonson

Eichler

2004

Journal of Biological Chemistry

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“…Cell Culture-Bovine aortic endothelial cells (BAEC) were cultured in Dulbecco's modified Eagle's medium (1 g/liter glucose, Mediatech) supplemented with 10% fetal bovine serum (Hyclone Laboratories), 100 units/ml penicillin, and 100 g/ml streptomycin (Mediatech) at 37°C and 5% CO 2 .…”

Section: Methodsmentioning

confidence: 99%

Regulation of Endothelial Argininosuccinate Synthase Expression and NO Production by an Upstream Open Reading Frame

Pendleton

Goodwin

Solomonson

et al. 2005

Journal of Biological Chemistry

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Argininosuccinate synthase (AS) catalyzes the ratelimiting step in the recycling of citrulline to arginine, which in endothelial cells, is tightly coupled to the production of nitric oxide (NO). In previous work, we established that endothelial AS mRNA can be initiated from multiple start sites, generating co-expressed mRNA variants with different 5-untranslated regions (5-UTRs). One of the 5-UTRs, the shortest form, represents greater than 90% of the total AS mRNA. Two other extended 5-UTR forms of AS mRNA, resulting from upstream initiations, contain an out-of-frame, upstream open reading frame (uORF). In this study, the function of the extended 5-UTRs of AS mRNA was investigated. Single base insertions to place the uORF in-frame, and mutations to extend the uORF, demonstrated functionality, both in vitro with AS constructs and in vivo with luciferase constructs. Overexpression of the uORF suppressed endothelial AS protein expression, whereas specific silencing of the uORF AS mRNAs resulted in the coordinate up-regulation of AS protein and NO production. Expression of the full-length of the uORF was necessary to mediate a trans-suppressive effect on endothelial AS expression, demonstrating that the translation product itself affects regulation. In conclusion, the uORF found in the extended, overlapping 5-UTR AS mRNA species suppresses endothelial AS expression, providing a novel mechanism for regulating endothelial NO production by limiting the availability of arginine. Nitric oxide (NO)1 synthesized from arginine by endothelial nitric-oxide synthase is a potent vasodilator and a critical modulator of blood flow and blood pressure. In addition, it mediates vasoprotective actions through inhibiting smooth muscle proliferation, platelet aggregation, and leukocyte adhesion (1-3). Under pathophysiological conditions associated with endothelial dysfunction, such as heart failure (4), hypertension, hypercholesterolemia, atherosclerosis (5), and diabetes (6), the ability to produce NO seems to be impaired. Paradoxically, NO production can be impaired by limited availability of the substrate arginine, despite apparently saturating levels of intracellular and extracellular arginine (7-10). We have previously shown that under normal conditions, the essential arginine available for NO production is derived from the recycling of citrulline to arginine, catalyzed by two enzymes, argininosuccinate synthase (AS) and argininosuccinate lyase (AL) (11,12). Although these two enzymes have been studied extensively in liver, where they participate in the urea cycle (13), it was not until the discovery of NO that their function in non-hepatic tissues was clarified. In endothelial cells, AS and AL play a critical role in the operation of a citrulline-NO cycle, which supports endothelial NO production (14 -17).Because AS catalyzes the rate-limiting step in the citrulline-NO cycle (15), our initial studies have focused on the molecular basis for the functional role of endothelial AS. Endothelial and hepatic AS appear to have the same ...

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“…NO synthesis is tightly regulated by the arginine-and Ca 2 + -dependent system, because NO is the product of L-arginine transformation to L-citrulline, and because two of the three isoforms of nitric oxide synthases (nNOS and eNOS) are Ca 2 + /calmodulin dependent, while only iNOS is insensitive to Ca 2 + . NO synthesis requires homodimerization and proper phosphorylation status of the NOS enzymes, as well as the presence of three co-substrates (L-arginine, NADPH, and molecular oxygen) and five cofactors (calmodulin, FAD, FMN, heme, and tetrahydrobiopterin) (37). In contrast to ROS, the physiological concentrations of NO generated by Ca 2 + -activated NOS enzymes are considered nontoxic (2).…”

Section: Cysteine S-nitrosylationmentioning

confidence: 99%

Reactive Nitrogen Species and Hydrogen Sulfide as Regulators of Protein Tyrosine Phosphatase Activity

Heneberg

2014

Antioxidants & Redox Signaling

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Significance: Redox modifications of thiols serve as a molecular code enabling precise and complex regulation of protein tyrosine phosphatases (PTPs) and other proteins. Particular gasotransmitters and even the redox modifications themselves affect each other, of which a typical example is S-nitrosylation-mediated protection against the further oxidation of protein thiols. Recent Advances: For a long time, PTPs were considered constitutively active housekeeping enzymes. This view has changed substantially over the last two decades, and the PTP family is now recognized as a group of tightly and flexibly regulated fundamental enzymes. In addition to the conventional ways in which they are regulated, including noncovalent interactions, phosphorylation, and oxidation, the evidence that has accumulated during the past two decades suggests that many of these enzymes are also modulated by gasotransmitters, namely by nitric oxide (NO) and hydrogen sulfide (H 2 S). Critical Issues: The specificity and selectivity of the methods used to detect nitrosylation and sulfhydration remains to be corroborated, because several researchers raised the issue of false-positive results, particularly when using the most widespread biotin switch method. Further development of robust and straightforward proteomic methods is needed to further improve our knowledge of the full extent of the gasotransmitters-mediated changes in PTP activity, selectivity, and specificity. Further Directions: Results of the hitherto performed studies on gasotransmitter-mediated PTP signaling await translation into clinical medicine and pharmacotherapeutics. In addition to directly affecting the activity of particular PTPs, the use of reversible S-nitrosylation as a protective mechanism against oxidative stress should be of high interest. Antioxid. Redox Signal. 20, 2191-2209.

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Nitric oxide chemistry and cellular signaling

Cited by 139 publications

References 67 publications

Argininosuccinate Synthase Expression Is Required to Maintain Nitric Oxide Production and Cell Viability in Aortic Endothelial Cells

Argininosuccinate Synthase Expression Is Required to Maintain Nitric Oxide Production and Cell Viability in Aortic Endothelial Cells

Regulation of Endothelial Argininosuccinate Synthase Expression and NO Production by an Upstream Open Reading Frame

Reactive Nitrogen Species and Hydrogen Sulfide as Regulators of Protein Tyrosine Phosphatase Activity

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