Impact of nitric oxide on macrophage glucose metabolism and glyceraldehyde-3-phosphate dehydrogenase activity

1995 ◽  
Vol 268 (3) ◽  
pp. C669-C675 ◽  
Author(s):  
R. B. Mateo ◽  
J. S. Reichner ◽  
B. Mastrofrancesco ◽  
D. Kraft-Stolar ◽  
J. E. Albina

Conflicting evidence has been presented regarding the role of nitric oxide (NO) in the regulation of cellular glucose metabolism. While it enhances glucose uptake and utilization through glycolysis and the hexose monophosphate shunt in macrophages and other cells, NO also inhibits glyceraldehyde-3-phosphate dehydrogenase, an enzyme catalyzing the metabolism of intermediates generated by both pathways. Indeed, it has been proposed that NO modulates glycolytic flux by suppressing glyceraldehyde-3-phosphate dehydrogenase activity. To establish the relative impact of these apparently incompatible actions, the effects of exogenous or endogenous NO on different aspects of glucose metabolism in macrophages were investigated. Cell activation increased NO production, maximal glyceraldehyde-3-phosphate dehydrogenase activity, and glucose metabolism through glycolysis and the hexose monophosphate shunt. NO generated endogenously or from S-nitroso-N-acetylpenicillamine (> 500 microM) reduced maximal glyceraldehyde-3-phosphate dehydrogenase activity in culture. The suppression of maximal glyceraldehyde-3-phosphate dehydrogenase coincided with decreased lactate accumulation only in concert with a marked loss of viable cells in the cultures. The maximal glyceraldehyde-3-phosphate dehydrogenase activity did not appear to be rate limiting for glucose metabolism when moderately inhibited by NO. A potential causal relationship between profound glyceraldehyde-3-phosphate dehydrogenase inhibition and cell death remains to be established.

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2646 ◽  
Author(s):  
Silvia Grottelli ◽  
Rosa Amoroso ◽  
Lara Macchioni ◽  
Fiorella D’Onofrio ◽  
Katia Fettucciari ◽  
...  

Neurodegenerative diseases are associated with increased levels of nitric oxide (NO) mainly produced by microglial cells through inducible nitric oxide synthase (iNOS) whose expression is induced by inflammatory stimuli. NO can both exert cytotoxic functions and induce a metabolic switch by inhibiting oxidative phosphorylation and upregulating glycolytic flux. Here, we investigated whether two newly synthesized acetamidine based iNOS inhibitors, namely CM292 and CM544, could inhibit lipopolysaccharide (LPS)-induced BV2 microglial cell activation, focusing on both inflammatory and metabolic profiles. We found that CM292 and CM544, without affecting iNOS protein expression, reduced NO production and reverted LPS-induced inflammatory and cytotoxic response. Furthermore, in the presence of the inflammatory stimulus, both the inhibitors increased the expression of glycolytic enzymes. In particular, CM292 significantly reduced nuclear accumulation of pyruvate kinase M2, increased mitochondrial membrane potential and oxygen consumption rate, and augmented the expression of pyruvate dehydrogenase, pointing to a metabolic switch toward oxidative phosphorylation. These data confirm the role played by NO in the connection between cell bioenergetics profile and inflammation, and suggest the potential usefulness of iNOS inhibitors in redirecting microglia from detrimental to pro-regenerative phenotype.


2018 ◽  
Vol 16 (2) ◽  
pp. 194-199
Author(s):  
Wioletta Ratajczak-Wrona ◽  
Ewa Jablonska

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.


2005 ◽  
Vol 289 (6) ◽  
pp. F1324-F1332 ◽  
Author(s):  
Manish M. Tiwari ◽  
Robert W. Brock ◽  
Judit K. Megyesi ◽  
Gur P. Kaushal ◽  
Philip R. Mayeux

Acute renal failure (ARF) is a frequent and serious complication of endotoxemia caused by lipopolysaccharide (LPS) and contributes significantly to mortality. The present studies were undertaken to examine the roles of nitric oxide (NO) and caspase activation on renal peritubular blood flow and apoptosis in a murine model of LPS-induced ARF. Male C57BL/6 mice treated with LPS ( Escherichia coli) at a dose of 10 mg/kg developed ARF at 18 h. Renal failure was associated with a significant decrease in peritubular capillary perfusion. Vessels with no flow increased from 7 ± 3% in the saline group to 30 ± 4% in the LPS group ( P < 0.01). Both the inducible NO synthase inhibitor l- N6-1-iminoethyl-lysine (l-NIL) and the nonselective caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp fluoromethylketone (Z-VAD) prevented renal failure and reversed perfusion deficits. Renal failure was also associated with an increase in renal caspase-3 activity and an increase in renal apoptosis. Both l-NIL and Z-VAD prevented these changes. LPS caused an increase in NO production that was blocked by l-NIL but not by Z-VAD. Taken together, these data suggest NO-mediated activation of renal caspases and the resulting disruption in peritubular blood flow are an important mechanism of LPS-induced ARF.


Author(s):  
Antoine Berger ◽  
Alexandre Boscari ◽  
Alain Puppo ◽  
Renaud Brouquisse

Abstract The interaction between legumes and rhizobia leads to the establishment of a symbiotic relationship between plant and bacteria. This is characterized by the formation of a new organ, the nodule, which facilitates the fixation of atmospheric nitrogen (N2) by nitrogenase through the creation of a hypoxic environment. Nitric oxide (NO) accumulates at each stage of the symbiotic process. NO is involved in defense responses, nodule organogenesis and development, nitrogen fixation metabolism, and senescence induction. During symbiosis, either successively or simultaneously, NO regulates gene expression, modulates enzyme activities, and acts as a metabolic intermediate in energy regeneration processes via phytoglobin-NO respiration and the bacterial denitrification pathway. Due to the transition from normoxia to hypoxia during nodule formation, and the progressive presence of the bacterial partner in the growing nodules, NO production and degradation pathways change during the symbiotic process. This review analyzes the different source and degradation pathways of NO, and highlights the role of nitrate reductases and hemoproteins of both the plant and bacterial partners in the control of NO accumulation.


2017 ◽  
Vol 398 (3) ◽  
pp. 319-329 ◽  
Author(s):  
Christine C. Helms ◽  
Xiaohua Liu ◽  
Daniel B. Kim-Shapiro

Abstract Nitrite was once thought to be inert in human physiology. However, research over the past few decades has established a link between nitrite and the production of nitric oxide (NO) that is potentiated under hypoxic and acidic conditions. Under this new role nitrite acts as a storage pool for bioavailable NO. The NO so produced is likely to play important roles in decreasing platelet activation, contributing to hypoxic vasodilation and minimizing blood-cell adhesion to endothelial cells. Researchers have proposed multiple mechanisms for nitrite reduction in the blood. However, NO production in blood must somehow overcome rapid scavenging by hemoglobin in order to be effective. Here we review the role of red blood cell hemoglobin in the reduction of nitrite and present recent research into mechanisms that may allow nitric oxide and other reactive nitrogen signaling species to escape the red blood cell.


2003 ◽  
Vol 1 (3) ◽  
pp. 113-117 ◽  
Author(s):  
M. Myronidou ◽  
B. Kokkas ◽  
A. Kouyoumtzis ◽  
N. Gregoriadis ◽  
A. Lourbopoulos ◽  
...  

In these studies we investigated if losartan, an AT1- receptor blocker has any beneficial effect on NO production from the bovine aortic preparations in vitro while under stimulation from angiotensin II. Experiments were performed on intact specimens of bovine thoracic aorta, incubated in Dulbeco's MOD medium in a metabolic shaker for 24 hours under 95 % O2 and 5 % CO2 at a temperature of 37°C. We found that angiotensin II 1nM−10 μM does not exert any statistically significant action on NO production. On the contrary, angiotensin II 10nM increases the production of NO by 58.14 % (from 12.16 + 2.9 μm/l to 19.23 + 4.2 μm/l in the presence of losartan 1nM (P<0.05). Nitric oxide levels depend on both rate production and rate catabolism or chemical inactivation. Such an equilibrium is vital for the normal function of many systems including the cardiovascular one. The above results demonstrate that the blockade of AT1-receptors favors the biosynthesis of NO and indicate the protective role of losartan on the vascular wall.


2000 ◽  
Vol 279 (2) ◽  
pp. H726-H732 ◽  
Author(s):  
Don D. Sheriff ◽  
Christopher D. Nelson ◽  
Ryan K. Sundermann

We sought to test the role of nitric oxide (NO) in governing skeletal muscle (iliac) vascular conductance during treadmill locomotion in dogs ( n = 6; 3.2 and 6.4 km/h at 0% grade, and 6.4 km/h at 10% grade). As seen previously, the increase in muscle vascular conductance accompanying treadmill locomotion was little influenced by NO synthase inhibition alone with N ω-nitro-l-arginine methyl ester (l-NAME, 10 mg/kg iv), but the absolute value of conductance achieved during locomotion was reduced. Such ambiguous results provide an unclear picture regarding the importance of NO during locomotion. However, muscle vasodilation is normally restrained by the sympathetic system during locomotion. Thus a significant contribution by NO to the increase in vascular conductance that accompanies locomotion could be masked by partial withdrawal of the competing influence of sympathetic vasoconstrictor nerve activity secondary to the rise in arterial pressure following systemicl-NAME administration. To test this possibility, we compared the rise in muscle vascular conductance before and afterl-NAME treatment while ganglionic transmission was blocked by hexamethonium. Under these conditions, l-NAME significantly reduced both the rise in vascular conductance (by 32%, P < 0.001) and the absolute level of vascular conductance (by 30%, P < 0.001) achieved during locomotion with no effect on blood flow. Thus augmented NO production normally provides a significant drive to relax vascular smooth muscle in active skeletal muscle during locomotion. Potential deficits stemming from the absence of NO following l-NAME treatment are masked by less intense sympathetic restraint when autonomic function is intact.


Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1484 ◽  
Author(s):  
Tamara Lechón ◽  
Luis Sanz ◽  
Inmaculada Sánchez-Vicente ◽  
Oscar Lorenzo

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.


Sign in / Sign up

Export Citation Format

Share Document