scholarly journals 4-Hydroxy-7-Methoxycoumarin Inhibits Inflammation in LPS-activated RAW264.7 Macrophages by Suppressing NF-κB and MAPK Activation

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4424
Author(s):  
Jin Kyu Kang ◽  
Chang-Gu Hyun

Coumarins are natural products with promising pharmacological activities owing to their anti-inflammatory, antioxidant, antiviral, anti-diabetic, and antimicrobial effects. Coumarins are present in many plants and microorganisms and have been widely used as complementary and alternative medicines. To date, the pharmacological efficacy of 4-hydroxy-7-methoxycoumarin (4H-7MTC) has not been reported yet. Therefore, in this study, we investigated the anti-inflammatory effects of 4H-7MTC in LPS-stimulated RAW264.7 cells as well as its mechanisms of action. Cells were treated with various concentrations of 4H-7MTC (0.3, 0.6, 0.9, and 1.2 mM) and 40 μM L-N6-(1-iminoethyl)-L-lysine (L-NIL) were used as controls. LPS-stimulated RAW264.7 cells showed that 4H-7MTC significantly reduced nitric oxide (NO) and prostaglandin E2 (PGE2) production without cytotoxic effects. In addition, 4H-7MTC strongly decreased the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2). Furthermore, 4H-7MTC reduced the production of proinflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. We also found that 4H-7MTC strongly exerted its anti-inflammatory actions by downregulating nuclear factor kappa B (NF-κB) activation by suppressing inhibitor of nuclear factor kappa B alpha (IκBα) degradation in macrophages. Moreover, 4H-7MTC decreased phosphorylation of extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase/stress-activated protein kinase (JNK), but not that of p38 MAPK. These results suggest that 4H-7MTC may be a good candidate for the treatment or prevention of inflammatory diseases such as dermatitis, psoriasis, and arthritis. Ultimately, this is the first report describing the effective anti-inflammatory activity of 4H-7MTC.

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2482 ◽  
Author(s):  
Yun-Da Yao ◽  
Xiu-Yu Shen ◽  
Jorge Machado ◽  
Jin-Fang Luo ◽  
Yi Dai ◽  
...  

Nardochinoid B (NAB) is a new compound isolated from Nardostachys chinensis. Although our previous study reported that the NAB suppressed the production of nitric oxide (NO) in lipopolysaccharide (LPS)-activated RAW264.7 cells, the specific mechanisms of anti-inflammatory action of NAB remains unknown. Thus, we examined the effects of NAB against LPS-induced inflammation. In this study, we found that NAB suppressed the LPS-induced inflammatory responses by restraining the expression of inducible nitric oxide synthase (iNOS) proteins and mRNA instead of cyclooxygenase-2 (COX-2) protein and mRNA in RAW264.7 cells, implying that NAB may have lower side effects compared with nonsteroidal anti-inflammatory drugs (NSAIDs). Besides, NAB upregulated the protein and mRNA expressions of heme oxygenase (HO)-1 when it exerted its anti-inflammatory effects. Also, NAB restrained the production of NO by increasing HO-1 expression in LPS-stimulated RAW264.7 cells. Thus, it is considered that the anti-inflammatory effect of NAB is associated with an induction of antioxidant protein HO-1, and thus NAB may be a potential HO-1 inducer for treating inflammatory diseases. Moreover, our study found that the inhibitory effect of NAB on NO is similar to that of the positive drug dexamethasone, suggesting that NAB has great potential for developing new drugs in treating inflammatory diseases.


2020 ◽  
Vol 21 (19) ◽  
pp. 7070
Author(s):  
Seul-Ki Mun ◽  
Kyung-Yun Kang ◽  
Ho-Yeol Jang ◽  
Yun-Ho Hwang ◽  
Seong-Gyeol Hong ◽  
...  

Lichens, composite organisms resulting from the symbiotic association between the fungi and algae, produce a variety of secondary metabolites that exhibit pharmacological activities. This study aimed to investigate the anti-inflammatory activities of the secondary metabolite atraric acid produced by Heterodermia hypoleuca. The results confirmed that atraric acid could regulate induced pro-inflammatory cytokine, nitric oxide, prostaglandin E2, induced nitric oxide synthase and cyclooxygenase-2 enzyme expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Meanwhile, atraric acid downregulated the expression of phosphorylated IκB, extracellular signal-regulated kinases (ERK) and nuclear factor kappa B (NFκB) signaling pathway to exhibit anti-inflammatory effects in LPS-stimulated RAW264.7 cells. Based on these results, the anti-inflammatory effect of atraric acid during LPS-induced endotoxin shock in a mouse model was confirmed. In the atraric acid treated-group, cytokine production was decreased in the peritoneum and serum, and each organ damaged by LPS-stimulation was recovered. These results indicate that atraric acid has an anti-inflammatory effect, which may be the underlying molecular mechanism involved in the inactivation of the ERK/NFκB signaling pathway, demonstrating its potential therapeutic value for treating inflammatory diseases.


2020 ◽  
Vol 19 (2) ◽  
pp. 164-171
Author(s):  
Feng Xue ◽  
Tingting Chen

Glioblastoma multiforme is the most common malignancy of central nervous system. Herein we have evaluated the effect of L-tetrahydropalmatine, an isoquinoline alkaloid, on the tumor growth both in vivo and in vitro using C6 glioblastoma multiforme cells and BALB/c mice injected subcutaneously with C6/luc2 cells. The results of these studies show that L-tetrahydropalmatine exhibited cytotoxic effect on C6 glioblastoma multiforme cells, suppressed nuclear factor-kappa B activity, suppressed the levels of tumor-linked proteins such as matrix metalloproteinase-2/9, Cyclin-D1, vascular endothelial growth factor, and X-linked inhibitor of apoptosis protein via ERK/nuclear factor-kappa B cascade. Further, L-tetrahydropalmatine inhibited the cell migration and invasion properties of C6 cells, and also suppressed the tumor weight and volume in mice. Immunohistochemical staining of tumor tissues suggested that L-tetrahydropalmatine inhibited the extracellular-signal-regulated kinase/nuclear factor-kappa B cascade and suppressed the levels of Cyclin-D1; matrix metalloproteinase-2/9; X-linked inhibitor of apoptosis protein; and vascular endothelial growth factor, and also the progression and growth of glioblastoma multiforme in mice. In summary, L-tetrahydropalmatine inhibits the ERK/nuclear factor-kappa B cascade, decreases the tumor volume, and inhibits the proteins responsible for tumor growth both in vivo and in vitro.


2006 ◽  
Vol 397 (3) ◽  
pp. 185-189 ◽  
Author(s):  
Eunyoung Ha ◽  
Kyung Hee Jung ◽  
Bong-Keun Choe ◽  
Jae-Hoon Bae ◽  
Dong-Hoon Shin ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Naren Bao ◽  
Bing Tang ◽  
Junke Wang

Acute kidney injury (AKI) is one of the most common and troublesome perioperative complications. Dexmedetomidine (DEX) is a potent α2-adrenoceptor (α2-AR) agonist with anti-inflammatory and renoprotective effects. In this study, a rat renal ischemia–reperfusion injury (IRI) model was induced. At 24 h after reperfusion, the IRI-induced damage and the renoprotection of DEX preconditioning were confirmed both biochemically and histologically. Changes in nuclear factor-kappa B (NF-κB), as well as its downstream anti-inflammatory factor A20 and proinflammatory factor tumor necrosis factor-α (TNF-α), were detected. Atipamezole, a nonselective antagonist, was then added 5 min before the administration of DEX to further analyze DEX’s effects on NF-κB, and another anti-inflammatory medicine, methylprednisolone, was used in comparison with DEX, to further analyze DEX’s effects on NF-κB. Different concentrations of DEX (0 nM, 0.1 nM, 1 nM, 10 nM, 100 nM, 1 μM, and 10 μM) were applied to preincubated human renal tubular epithelial cell line (HK-2) cells in vitro. After anoxia and reoxygenation, the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium assay and enzyme-linked immunosorbent assay (ELISA) were performed to evaluate the levels of NF-κB downstream anti-inflammatory cytokines. The results showed that, unlike methylprednisolone, DEX preconditioning led to a time-dependent biphasic change (first activation then inhibition) of NF-κB in the rat renal IRI models that were given 25 μg/kg i.p. It was accompanied by a similarly biphasic change of TNF-α and an early and persistent upregulation of A20. In vitro, DEX’s cellular protection showed a concentration-dependent biphasic change which was protective within the range of 0 to 100 nM but became opposite when concentrations are greater than 1 μM. The changes in the A20 and NF-κB messenger RNA (mRNA) levels were consistent with the renoprotective ability of DEX. In other words, DEX preconditioning protected the rats from renal IRI via regulation biphasic change of NF-κB signaling.


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