Suppression of Nitric Oxide Synthase by Thienodolin in Lipopolysaccharide-stimulated RAW 264.7 Murine Macrophage Cells

The measurement of nitric oxide in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells is used as a model for evaluating the anti-inflammatory or chemopreventive potential of substances. Thienodolin, isolated from a Streptomyces sp. derived from Chilean marine sediment, inhibited nitric oxide production in LPS-stimulated RAW 264.7 cells (IC50 = 17.2 ± 1.2 μM). At both the mRNA and protein levels, inducible nitric oxide synthase (iNOS) was suppressed in a dose-dependent manner. Mitogen-activated protein kinases (MAPKs), one major upstream signaling pathway involved in the transcription of iNOS, were not affected by treatment of thienodolin. However, the compound blocked the degradation of IκBα resulting in inhibition of NF-κB p65 nuclear translocation, and inhibited the phosphorylation of signal transducers and activators of transcription 1 (STAT1) at Tyr701. This study supports further exploration of thienodolin as a potential therapeutic agent with a unique mechanistic activity.

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Melatonin suppresses macrophage cyclooxygenase-2 and inducible nitric oxide synthase expression by inhibiting p52 acetylation and binding

Blood ◽

10.1182/blood-2005-09-3691 ◽

2006 ◽

Vol 108 (2) ◽

pp. 518-524 ◽

Cited By ~ 149

Author(s):

Wu-Guo Deng ◽

Shao-Tzu Tang ◽

Hui-Ping Tseng ◽

Kenneth K. Wu

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Inducible Nitric Oxide Synthase ◽

Nuclear Translocation ◽

Cyclooxygenase 2 ◽

Raw 264.7 Cells ◽

Dependent Manner ◽

Cox 2 ◽

Oxide Synthase ◽

Inducible Nitric Oxide

Melatonin has been shown to be produced by nonpineal cells and possess anti-inflammatory actions in animal models. In the present study, we tested the hypothesis that melatonin suppresses the expression of proinflammatory genes such as cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (INOS) by a common transcriptional mechanism. Melatonin but not tryptophan or serotonin inhibited lipopolysaccharide (LPS)–induced COX-2 and iNOS protein levels and promoter activities in RAW 264.7 cells in a time- and concentration-dependent manner. LPS or LPS plus interferon-γ (IFNγ) increased binding of all 5 isoforms of NF-κB to COX-2 and iNOS promoters. Melatonin selectively inhibited p52 binding without affecting p100 expression, p52 generation from p100, or p52 nuclear translocation. p52 acetylation was enhanced by LPS, which was abrogated by melatonin. Melatonin inhibited p300 histone acetyltransferase (HAT) activity and abrogated p300-augmented COX-2 and iNOS expression. HAT inhibitors suppressed LPS-induced p52 binding and acetylation to an extent similar to melatonin, and melatonin did not potentiate the effect of HAT inhibitors. These results suggest that melatonin inhibits COX-2 and iNOS transcriptional activation by inhibiting p300 HAT activity, thereby suppressing p52 acetylation, binding, and transactivation.

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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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Anti-inflammatory Activity of the Synthetic Chalcone Derivatives: Inhibition of Inducible Nitric Oxide Synthase-Catalyzed Nitric Oxide Production from Lipopolysaccharide-Treated RAW 264.7 Cells

Biological and Pharmaceutical Bulletin ◽

10.1248/bpb.30.1450 ◽

2007 ◽

Vol 30 (8) ◽

pp. 1450-1455 ◽

Cited By ~ 43

Author(s):

Young Hoon Kim ◽

Jeongsoo Kim ◽

Haeil Park ◽

Hyun Pyo Kim

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Inducible Nitric Oxide Synthase ◽

Inflammatory Activity ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Nitric Oxide Production ◽

Oxide Production ◽

Oxide Synthase ◽

Inducible Nitric Oxide

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Inhibitory Effect of 1,5-Dimethyl Citrate from Sea Buckthorn (Hippophae rhamnoides) on Lipopolysaccharide-Induced Inflammatory Response in RAW 264.7 Mouse Macrophages

Foods ◽

10.3390/foods9030269 ◽

2020 ◽

Vol 9 (3) ◽

pp. 269 ◽

Cited By ~ 1

Author(s):

Su Cheol Baek ◽

Dahae Lee ◽

Mun Seok Jo ◽

Kwang Ho Lee ◽

Yong Hoon Lee ◽

...

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Sea Buckthorn ◽

Raw 264.7 Cells ◽

No Production ◽

Raw 264.7 ◽

Tnf Α ◽

Mouse Macrophages ◽

Cox 2 ◽

Oxide Synthase

Hippophae rhamnoides L. (Elaeagnaceae; commonly known as “sea buckthorn” and “vitamin tree”), is a spiny deciduous shrub whose fruit is used in foods and traditional medicines. The H. rhamnoides fruit (berry) is rich in vitamin C, with a level exceeding that found in lemons and oranges. H. rhamnoides berries are usually washed and pressed to create pomace and juice. Today, the powder of the aqueous extract of H. rhamnoides berries are sold as a functional food in many countries. As part of our ongoing effort to identify bioactive constituents from natural resources, we aimed to isolate and identify those from the fruits of H. rhamnoides. Phytochemical analysis of the extract of H. rhamnoides fruits led to the isolation and identification of six compounds, namely, a citric acid derivative (1), a phenolic (2), flavonoids (3 and 4), and megastigmane compounds (5 and 6). Treatment with compounds 1–6 did not have any impact on the cell viability of RAW 264.7 mouse macrophages. However, pretreatment with these compounds suppressed lipopolysaccharide (LPS)-induced NO production in RAW 264.7 mouse macrophages in a concentration-dependent manner. Among the isolated compounds, compound 1 was identified as the most active, with an IC50 of 39.76 ± 0.16 μM. This value was comparable to that of the NG-methyl-L-arginine acetate salt, a nitric oxide synthase inhibitor with an IC50 of 28.48 ± 0.05 μM. Western blot analysis demonstrated that compound 1 inhibited the LPS-induced expression of IKKα/β (IκB kinase alpha/beta), I-κBα (inhibitor of kappa B alpha), nuclear factor kappa-B (NF-κB) p65, iNOS (inducible nitric oxide synthase), and COX-2 (cyclooxygenase-2) in RAW 264.7 cells. Furthermore, LPS-stimulated cytokine production was detected using a sandwich enzyme-linked immunosorbent assay. Compound 1 decreased interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) production in LPS-stimulated RAW 264.7 cells. In summary, the mechanism of action of 1 included the suppression of LPS-induced NO production in RAW 264.7 cells by inhibiting IKKα/β, I-κBα, NF-κB p65, iNOS, and COX-2, and the activities of IL-6 and TNF-α.

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