Effect of culture Po2on macrophage (RAW 264.7) nitric oxide production

Macrophages are commonly cultured at a Po2of 149 Torr, but tissue macrophages in vivo live in an environment of much lower oxygen tension. Despite the many potential mechanisms for changes in oxygen tension to influence nitric oxide (NO) synthesis, there have been few reports investigating the effect of Po2on macrophage NO production. With the use of a culture chamber designed to rigorously control oxygen tension, we investigated the effects of culture Po2on macrophage NO production, inducible nitric oxide synthase (iNOS) activity, iNOS protein, and tumor necrosis factor production. NO production and iNOS activity were linearly related in the range of 39.4 to 677 Torr, but not in the range of 1.03 to 39.4 Torr. Therefore, results obtained in vitro for the high oxygen tensions commonly used in cell culture were quantitatively and qualitatively different from results obtained in cells cultured at the lower oxygen tensions that more accurately reflect the in vivo environment. The influence of oxygen tension on NO production has implications for cell culture methodology and for the relationship between microcirculatory dysfunction and inflammatory responses in rodent models of sepsis.

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Effects of chitosan on nitric oxide production and inducible nitric oxide synthase activity and mRNA expression in weaned piglets

Czech Journal of Animal Science ◽

10.17221/8405-cjas ◽

2018 ◽

Vol 60 (No. 8) ◽

pp. 359-366

Author(s):

J. Li ◽

B. Shi ◽

S. Yan ◽

L. Jin ◽

Y. Guo ◽

...

Keyword(s):

Nitric Oxide ◽

Mrna Expression ◽

Inducible Nitric Oxide Synthase ◽

No Production ◽

Weaned Piglets ◽

Inos Activity ◽

Oxide Synthase ◽

Inducible Nitric Oxide

The effects of chitosan on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity and gene expression in vivo or vitro were investigated in weaned piglets. In vivo, 180 weaned piglets were assigned to five dietary treatments with six replicates. The piglets were fed on a basal diet supplemented with 0 (control), 100, 500, 1000, and 2000 mg chitosan/kg feed, respectively. In vitro, the peripheral blood mononuclear cells (PBMCs) from a weaned piglet were cultured respectively with 0 (control), 40, 80, 160, and 320 µg chitosan/ml medium. Results showed that serum NO concentrations on days 14 and 28 and iNOS activity on day 28 were quadratically improved with increasing chitosan dose (P < 0.05). The iNOS mRNA expressions were linearly or quadratically enhanced in the duodenum on day 28, and were improved quadratically in the jejunum on days 14 and 28 and in the ileum on day 28 (P < 0.01). In vitro, the NO concentrations, iNOS activity, and mRNA expression in unstimulated PBMCs were quadratically enhanced by chitosan, but the improvement of NO concentrations and iNOS activity by chitosan were markedly inhibited by N-(3-[aminomethyl] benzyl) acetamidine (1400w) (P < 0.05). Moreover, the increase of NO concentrations, iNOS activity, and mRNA expression in PBMCs induced by lipopolysaccharide (LPS) were suppressed significantly by chitosan (P < 0.05). The results indicated that the NO concentrations, iNOS activity, and mRNA expression in piglets were increased by feeding chitosan in a dose-dependent manner. In addition, chitosan improved the NO production in unstimulated PBMCs but inhibited its production in LPS-induced cells, which exerted bidirectional regulatory effects on the NO production via modulated iNOS activity and mRNA expression.

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In Vitro Study of Nitric Oxide Metabolites Effects on Human Hydatid ofEchinococcus granulosus

Journal of Parasitology Research ◽

10.1155/2009/624919 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 17

Author(s):

Razika Zeghir-Bouteldja ◽

Manel Amri ◽

Saliha Aitaissa ◽

Samia Bouaziz ◽

Dalila Mezioug ◽

...

Keyword(s):

Nitric Oxide ◽

Hydatid Cyst ◽

Echinococcus Granulosus ◽

In Vitro Study ◽

No Production ◽

In Vitro Effects ◽

Nitric Oxide Metabolites

Hydatidosis is characterized by the long-term coexistence of larvaEchinococcus granulosusand its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO2−), nitrate (NO3−) and peroxynitrite (ONOO−) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity ofNO2−andONOO−24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated thatONOO−is more cytotoxic thanNO2−. In contrast,NO3−has no effect. These results suggest possible involvement ofNO2−andONOO−in antihydatic action and point the efficacy of these metabolites as scolicidal agents.

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In vitro and in vivo anti-inflammatory activities of a sterol-enriched fraction from freshwater green alga, Spirogyra sp.

Fisheries and Aquatic Sciences ◽

10.1186/s41240-020-00172-9 ◽

2020 ◽

Vol 23 (1) ◽

Author(s):

Lei Wang ◽

You-Jin Jeon ◽

Jae-Il Kim

Keyword(s):

Nitric Oxide ◽

Green Alga ◽

Raw 264.7 Cells ◽

Ros Generation ◽

Prostaglandin E ◽

No Production ◽

Raw 264.7 ◽

Anti Inflammatory

Abstract Background Inflammation plays a crucial role in the pathogenesis of many diseases such as arthritis and atherosclerosis. In the present study, we evaluated anti-inflammatory activity of sterol-rich fraction prepared from Spirogyra sp., a freshwater green alga, in an effort to find bioactive extracts derived from natural sources. Methods The sterol content of ethanol extract of Spirogyra sp. (SPE) was enriched by fractionation with hexane (SPEH), resulting 6.7 times higher than SPE. Using this fraction, the in vitro and in vivo anti-inflammatory activities were evaluated in lipopolysaccharides (LPS)-stimulated RAW 264.7 cells and zebrafish. Results SPEH effectively and dose-dependently decreased the production of nitric oxide (NO) and prostaglandin E2 (PGE2). SPEH suppressed the production of pro-inflammatory cytokines including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and IL-1β through downregulating nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW 264.7 cells without cytotoxicity. The in vivo test results indicated that SPEH significantly and dose-dependently reduced reactive oxygen species (ROS) generation, cell death, and NO production in LPS-stimulated zebrafish. Conclusions These results demonstrate that SPEH possesses strong in vitro and in vivo anti-inflammatory activities and has the potential to be used as healthcare or pharmaceutical material for the treatment of inflammatory diseases.

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Heme proteins mediate the conversion of nitrite to nitric oxide in the vascular wall

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00374.2008 ◽

2008 ◽

Vol 295 (2) ◽

pp. H499-H508 ◽

Cited By ~ 83

Author(s):

Wael F. Alzawahra ◽

M. A. Hassan Talukder ◽

Xiaoping Liu ◽

Alexandre Samouilov ◽

Jay L. Zweier

Keyword(s):

Nitric Oxide ◽

Heme Proteins ◽

Soluble Guanylyl Cyclase ◽

Vascular Wall ◽

Rat Aorta ◽

No Production ◽

Paramagnetic Resonance ◽

Physiological Importance

Nitric oxide (NO) has been shown to be the endothelium-derived relaxing factor (EDRF), and its impairment contributes to a variety of cardiovascular disorders. Recently, it has been recognized that nitrite can be an important source of NO; however, questions remain regarding the activity and mechanisms of nitrite bioactivation in vessels and its physiological importance. Therefore, we investigated the effects of nitrite on in vivo hemodynamics in rats and in vitro vasorelaxation in isolated rat aorta under aerobic conditions. Studies were performed to determine the mechanisms by which nitrite is converted to NO. In anesthetized rats, nitrite dose dependently decreased both systolic and diastolic blood pressure with a threshold dose of 10 μM. Similarly, nitrite (10 μM-2 mM) caused vasorelaxation of aortic rings, and NO was shown to be the intermediate factor responsible for this activity. With the use of electrochemical as well as electron paramagnetic resonance (EPR) spectroscopy techniques NO generation was measured from isolated aortic vessels following nitrite treatment. Reduction of nitrite to NO was blocked by heating the vessel, suggesting that an enzymatic process is involved. Organ chamber experiments demonstrated that aortic relaxation induced by nitrite could be blocked by both hemoglobin and soluble guanylyl cyclase (sGC) inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ). In addition, both electrochemical and EPR spin-trapping measurements showed that ODQ inhibits nitrite-mediated NO production. These findings thus suggest that nitrite can be a precursor of EDRF and that sGC or other heme proteins inhibited by ODQ catalyze the reduction of nitrite to NO.

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The effects of disodium pamidronate on human polymorphonuclear leukocytes and platelets: An in vitro study

Cellular & Molecular Biology Letters ◽

10.2478/s11658-009-0012-6 ◽

2009 ◽

Vol 14 (3) ◽

Cited By ~ 5

Author(s):

Eleonora Salvolini ◽

Monia Orciani ◽

Arianna Vignini ◽

Roberto Primio ◽

Laura Mazzanti

Keyword(s):

Nitric Oxide ◽

In Vitro Study ◽

Protective Mechanism ◽

No Production ◽

Myeloperoxidase Activity ◽

Inflammatory Processes ◽

Anti Inflammatory ◽

Constitutive Nitric Oxide Synthase

AbstractRecent reports have indicated that, as well as having antiresorptive effects, bisphosphonates could have an application as anti-inflammatory drugs. Our aim was to investigate whether this anti-inflammatory action could be mediated by the nitric oxide (NO) released by the leukocytes migrating to the site of inflammation. In particular, we investigated in vitro the intracellular calcium concentration ([Ca2+]i), the level of NO released by PMN and platelets, and the PMN myeloperoxidase activity after incubation with disodium pamidronate, since there was a postulated modulatory effect of this aminosubstituted bisphosphonate on leukocytes both in vitro and in vivo. Our data shows that the pamidronate treatment provoked a significant increase in the [Ca2+]i parallel to the enhancement in NO release, suggesting a possible activation of constitutive nitric oxide synthase, while the myeloperoxidase activity was significantly reduced. In conclusion, we hypothesized that treatment with pamidronate could stimulate NO-production by cells present near the bone compartment, thus constituting a protective mechanism against bone resorption occurring during inflammation. In addition, PMN- and platelet-derived NO could act as a negative feed-back signal to restrict the inflammatory processes.

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Crambescin C1 Acts as A Possible Substrate of iNOS and eNOS Increasing Nitric Oxide Production and Inducing In Vivo Hypotensive Effect

Frontiers in Pharmacology ◽

10.3389/fphar.2021.694639 ◽

2021 ◽

Vol 12 ◽

Author(s):

Juan A. Rubiolo ◽

Emilio Lence ◽

Concepción González-Bello ◽

María Roel ◽

José Gil-Longo ◽

...

Keyword(s):

Nitric Oxide ◽

Active Site ◽

In Silico ◽

Hypotensive Effect ◽

Docking Studies ◽

No Production ◽

Guanidine Alkaloids ◽

Endogenous Substrate

Crambescins are guanidine alkaloids from the sponge Crambe crambe. Crambescin C1 (CC) induces metallothionein genes and nitric oxide (NO) is one of the triggers. We studied and compared the in vitro, in vivo, and in silico effects of some crambescine A and C analogs. HepG2 gene expression was analyzed using microarrays. Vasodilation was studied in rat aortic rings. In vivo hypotensive effect was directly measured in anesthetized rats. The targets of crambescines were studied in silico. CC and homo-crambescine C1 (HCC), but not crambescine A1 (CA), induced metallothioneins transcripts. CC increased NO production in HepG2 cells. In isolated rat aortic rings, CC and HCC induced an endothelium-dependent relaxation related to eNOS activation and an endothelium-independent relaxation related to iNOS activation, hence both compounds increase NO and reduce vascular tone. In silico analysis also points to eNOS and iNOS as targets of Crambescin C1 and source of NO increment. CC effect is mediated through crambescin binding to the active site of eNOS and iNOS. CC docking studies in iNOS and eNOS active site revealed hydrogen bonding of the hydroxylated chain with residues Glu377 and Glu361, involved in the substrate recognition, and explains its higher binding affinity than CA. The later interaction and the extra polar contacts with its pyrimidine moiety, absent in the endogenous substrate, explain its role as exogenous substrate of NOSs and NO production. Our results suggest that CC serve as a basis to develop new useful drugs when bioavailability of NO is perturbed.

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L-Theanine Reduced the Development of Knee Osteoarthritis in Rats via Its Anti-Inflammation and Anti-Matrix Degradation Actions: In Vivo and In Vitro Study

Nutrients ◽

10.3390/nu12071988 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1988 ◽

Cited By ~ 1

Author(s):

Hui Bai ◽

Zhiheng Zhang ◽

Yue Li ◽

Xiaopeng Song ◽

Tianwen Ma ◽

...

Keyword(s):

Nitric Oxide ◽

Inflammatory Cytokines ◽

Inflammatory Responses ◽

Quantitative Polymerase Chain Reaction ◽

Hydrolytic Enzyme ◽

Enzyme Linked Immunosorbent Assay ◽

Matrix Degradation ◽

In Vivo Animal Model

The etiology of osteoarthritis (OA) is multifactorial, with no effective disease-modifying-drugs. L-theanine has been reported to inhibit inflammatory responses in some diseases and this study aimed to investigate the effect of L-theanine on Interleukin-1(IL-1)β-stimulated chondrocytes, and in an injury-induced OA rat model. Primary chondrocytes were stimulated by IL-1β (10 ng/mL) for 24 h and then co-cultured with L-theanine for 24 h. The effects of L-theanine on IL-1β-stimulated expression of pro-inflammatory cytokines and hydrolytic enzyme were analyzed using Western blotting, quantitative polymerase chain reaction (q-PCR) and enzyme-linked immunosorbent assay (ELISA) kits. An immunofluorescence assay was used to detect nuclear factor kappa B (NF-κB) phosphorylation. OA was induced by anterior cruciate ligament transection (ACLT) surgery in rats and celecoxib was used as a positive control. OA severity was measured using the Osteoarthritis Research Society International (OARSI) grading system to describe histological changes. The results showed that L-theanine decreased the expression of pro-inflammatory mediators, including cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE-2), inducible nitric oxide synthase (iNOS), and nitric oxide (NO), both in vivo and in vitro. L-theanine treatment inhibited IL-1β-induced upregulation of matrix metalloproteinases (MMP)-3 and MMP-13, as well as inhibited NF-κB p65 activation. In vivo animal model showed that L-theanine administration (200 mg/kg) significantly alleviated OA lesions and decreased OARSI score. Our data indicated that L-theanine decreased inflammatory cytokines and protected extracellular matrix degradation through inhibition of the NF-κB pathway, and L-theanine may be considered a promising therapeutic strategy in OA prevention.

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Anti-Inflammatory Functions of Alverine via Targeting Src in the NF-κB Pathway

Biomolecules ◽

10.3390/biom10040611 ◽

2020 ◽

Vol 10 (4) ◽

pp. 611

Author(s):

Chae Young Lee ◽

Han Gyung Kim ◽

Sang Hee Park ◽

Seok Gu Jang ◽

Kyung Ja Park ◽

...

Keyword(s):

Nitric Oxide ◽

Inflammatory Responses ◽

Contractile Activity ◽

Hek293 Cells ◽

Poly I:C ◽

Raw264.7 Cells ◽

Gastric Ulcers ◽

Anti Inflammatory

Alverine, a smooth muscle relaxant, is used to relieve cramps or spasms of the stomach and intestine. Although the effects of alverine on spontaneous and induced contractile activity are well known, its anti-inflammatory activity has not been fully evaluated. In this study, we investigated the anti-inflammatory effects of alverine in vitro and in vivo. The production of nitric oxide (NO) in RAW264.7 cells activated by lipopolysaccharide (LPS) or polyinosinic:polycytidylic acid (poly (I:C)) was reduced by alverine. The mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) was also dose-dependently inhibited by treatment with alverine. In reporter gene assays, alverine clearly decreased luciferase activity, mediated by the transcription factor nuclear factor κB (NF-κB) in TIR-domain-containing adapter-inducing interferon-β (TRIF)- or MyD88-overexpressing HEK293 cells. Additionally, phosphorylation of NF-κB subunits and upstream signaling molecules, including p65, p50, AKT, IκBα, and Src was downregulated by 200 μM of alverine in LPS-treated RAW264.7 cells. Using immunoblotting and cellular thermal shift assays (CETSAs), Src was identified as the target of alverine in its anti-inflammatory response. In addition, HCl/EtOH-stimulated gastric ulcers in mice were ameliorated by alverine at doses of 100 and 200 mg/kg. In conclusion, alverine reduced inflammatory responses by targeting Src in the NF-κB pathway, and these findings provide new insights into the development of anti-inflammatory drugs.

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Effect of Peganum Harmala Seeds Extract on Nitric Oxide in U937 Monocytes and Macrophages

International Journal of Medical Laboratory ◽

10.18502/ijml.v7i4.4803 ◽

2020 ◽

Author(s):

Nima Rahmati ◽

Fatemeh Hajighasemi

Keyword(s):

Nitric Oxide ◽

Aqueous Extract ◽

Calf Serum ◽

Peritoneal Macrophages ◽

No Production ◽

Peganum Harmala ◽

Logarithmic Growth Phase ◽

Anti Inflammatory

Background and Aims: Nitric oxide (NO) has an essential role in inflammation and has been related to pathogenesis and the progress of numerous inflammatory-based diseases, including some cancers. Peganum harmala (P. harmala) is a medicinal plant used for the treatment of numerous diseases such as several infections. Also, anti-inflammatory effects of P. harmala extracts and its derivatives (harmaline and harmine) by suppressing myeloperoxidase, NO, and other mediators have been demonstrated in vivo. In this study, the effect of P. harmala seeds aqueous extract on NO production in U937 monocytic cells and peritoneal macrophages has been evaluated in vitro. Materials and Methods: U937 and mice peritoneal macrophages were cultured in Roswell Park Memorial institute-1640 with 10% fetal calf serum. Then, the cells at the logarithmic growth phase were incubated with different concentrations of aqueous extract of P. harmala seeds (0.1-1 mg/ml) for 24 hours. Next, NO production was assessed by the Griess method in the culture medium. Results: P. harmala seeds aqueous extract did not significantly affect lipopolysaccharide-induced NO production in U937 cells and peritoneal macrophages after 24 hours incubation time compared with untreated control cells. Conclusion: These results suggest that the anti-inflammatory effects of P. harmala may be mediated through NO-independent mechanism(s). However, further studies are warranted to define the P. harmala aqueous extract impact on NO expression in other related normal and cancerous cells.

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