• Title/Summary/Keyword: Cyclooxygenase pathways

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Imperatorin Suppresses Degranulation and Eicosanoid Generation in Activated Bone Marrow-Derived Mast Cells

  • Jeong, Kyu-Tae;Lee, Eujin;Park, Na-Young;Kim, Sun-Gun;Park, Hyo-Hyun;Lee, Jiean;Lee, Youn Ju;Lee, Eunkyung
    • Biomolecules & Therapeutics
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    • v.23 no.5
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    • pp.421-427
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    • 2015
  • Imperatorin has been known to exert many biological functions including anti-inflammatory activity. In this study, we investigated the inhibitory effects of imperatorin on the production of inflammatory mediators in mouse bone marrow-derived mast cells (BMMC). Imperatorin inhibited degranulation and the generation of eicosanoids (leukotriene $C_4$ ($LTC_4$) and prostaglandin $D_2$ ($PGD_2$) in IgE/antigen (Ag)-stimulated BMMC. To elucidate the molecular mechanism involved in this process, we investigated the effect of imperatorin on intracellular signaling in BMMC. Biochemical analyses of the IgE/Ag-mediated signaling pathway demonstrated that imperatorin dramatically attenuated degranulation and the production of 5-lipoxygenase-dependent $LTC_4$ and cyclooxygenase-2-dependent $PGD_2$ through the inhibition of intracellular calcium influx/phospholipase $C{\gamma}1$, cytosolic phospholipase $A_2$/mitogen-activated protein kinases and/or nuclear factor-${\kappa}B$ pathways in BMMC. These results suggest that the effects of imperatorin on inhibition of degranulation and eicosanoid generation through the suppression of multiple steps of IgE/Ag-mediated signaling pathways would be beneficial for the prevention of allergic inflammation.

Korean Red Ginseng mitigates spinal demyelination in a model of acute multiple sclerosis by downregulating p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways

  • Lee, Min Jung;Chang, Byung Joon;Oh, Seikwan;Nah, Seung-Yeol;Cho, Ik-Hyun
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.436-446
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    • 2018
  • Background: The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated. Methods: We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination. Results: Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein $(MBP)_{68-82}$ peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-${\gamma}$, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor ${\beta}1$, transforming growth factor ${\beta}$, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-${\kappa}B$ signaling pathways in microglia/macrophages, T cells, and astrocytes. Conclusion: Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-${\kappa}B$ signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

Anti-Inflammatory Potential of Probiotic Strain Weissella cibaria JW15 Isolated from Kimchi through Regulation of NF-κB and MAPKs Pathways in LPS-Induced RAW 264.7 Cells

  • Yu, Hyung-Seok;Lee, Na-Kyoung;Choi, Ae-Jin;Choe, Jeong-Sook;Bae, Chun Ho;Paik, Hyun-Dong
    • Journal of Microbiology and Biotechnology
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    • v.29 no.7
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    • pp.1022-1032
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    • 2019
  • Probiotics are known to provide the host with immune-modulatory effects and are therefore of remarkable interest for therapeutic and prophylactic applications against various disorders, including inflammatory diseases. Weissella cibaria JW15 (JW15) has been reported to possess probiotic and antioxidant properties. However, the effect of JW15 on inflammatory responses has not yet been reported. Therefore, the objective of the current study was to evaluate the anti-inflammatory potential of JW15 against lipopolysaccharide (LPS) stimulation. The production of pro-inflammatory factors and the cellular signaling pathways following treatment with heat-killed JW15 was examined in LPS-induced RAW 264.7 cells. Treatment with heat-killed JW15 decreased nitric oxide and prostaglandin $E_2$ production via down-regulation of the inducible nitric oxide synthase and cyclooxygenase-2. In addition, treatment with heat-killed JW15 suppressed the expression of pro-inflammatory cytokines, interleukin $(IL)-1{\beta}$, IL-6, and tumor necrosis factor-${\alpha}$. The anti-inflammatory properties of treating with heat-killed JW15 were associated with mitogen-activated protein kinase signaling pathway-mediated suppression of nuclear factor-${\kappa}B$. These results indicated that JW15 possesses anti-inflammatory potential and provide a molecular basis regarding the development of functional probiotic products.

Fermentation enhances the antioxidant and anti-inflammatory effects of Bat Faeces (Ye Ming Sha) via the ERK, p38 MAPK and NF-κB signaling pathways in RAW 264.7 cells

  • Lee, Han-Saem;Chon, So-Hyun;Kim, Min-A;Park, Jeong-Eun;Lim, Yu-Mi;Kim, Eun-Jeong;Son, Eun-Kyung;Kim, Sang-Jun;So, Jai-Hyun
    • Journal of Applied Biological Chemistry
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    • v.62 no.1
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    • pp.57-66
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    • 2019
  • The ethyl acetate fraction of Bat Faeces (Ye Ming Sha: natural products used in Chinese Medicine) after fermentation (EFBF-AF) showed enhanced anti-oxidative effects in 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt assays. Fermentation of the Bat Faeces by using the crude enzyme extract from Aspergillus kawachii, significantly increased the anti-inflammatory effects. Fermented Bat Faeces markedly inhibited nitric oxide production, inducible nitric oxide synthase, and cyclooxygenase-2 expression in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The EFBF-AF reduced the nuclear translocation of nuclear factor kappa B ($NF-{\kappa}B$) via $IKK{\alpha}$ and $I{\kappa}B{\alpha}$ phosphorylation, and decreased the phosphorylated the extracellular signal-regulated kinases (ERK) and p38 expression in LPS-treated RAW 264.7 macrophages. In addition, the EFBF-AF suppressed the expression of pro-inflammatory genes, such as interleukin-$1{\beta}$, interleukin-6, and tumor necrosis $factor-{\alpha}$. These results suggest that fermented Bat Faeces may suppress pro-inflammatory responses in LPS-stimulated RAW 264.7 macrophages cells via ERK, p38 mitogen-activated protein kinase and $NF-{\kappa}B$ signaling pathways.

Cudrania Tricuspidata root extract (CTE) has an anti-platelet effect via cGMP-dependent VASP phosphorylation in human platelets (꾸지뽕나무 뿌리 추출물의 cGMP에 의한 VASP 인산화 기전을 통한 항혈소판 효과)

  • Ro, Ju-Ye;Cho, Hyun-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.298-305
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    • 2019
  • Cudrania tricuspidata has been reported to have many biological activities, including anti-inflammatory, anti-cancer, and antioxidant properties. However, the effects of C. tricuspidata root extract (CTE) on human platelet aggregation induced by collagen as well as the signaling pathways involved remain unknown. In the present study, we investigated the effect of CTE on human platelets. CTE inhibited platelet aggregation via down-regulation of thromboxane A2 (TXA2) by blocking cyclooxygenase-1 (COX-1) activity and intracellular Ca2+ mobilization in collagen-induced platelets. CTE also reduced the phosphorylation of phospholipase C (PLC) γ2 and syk. CTE regulated platelet aggregation via cyclic guanosine monophosphate (cGMP)-dependent phosphorylation of vasodilator-stimulated phosphoprotein (VASP) Ser239. In addition, administration of CTE (50 and 100 mg/kg) significantly reduced hyper-aggregated platelet aggregation by collagen (5 ㎍/mL) without hepatotoxicity in HFD (high fat diet)-fed rats. Taken together, these results suggest that CTE has anti-platelet effects both in vitro and in vivo. Therefore, CTE may be an effective therapeutic and preventive agent for cardiovascular disease, and is a safe and natural product.

Suppression of the Expression of Cyclooxygenase-2 Induced by Toll-like Receptor 2, 3, and 4 Agonists by 6-Shogaol (6-Shogaol의 Toll-like receptor 2, 3, 4 agonists에 의해서 유도된 cyclooxygenase-2 발현 억제)

  • Kim, Jeom-Ji;An, Sang-Il;Lee, Jeon-Su;Yun, Sae-Mi;Lee, Mi-Yeong;Yun, Hyeong-Seon
    • Korean Journal of Food Science and Technology
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    • v.40 no.3
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    • pp.332-336
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    • 2008
  • Ginger is widely used as a traditional herbal medicine. Both ginger and its extracts have been used to treat many chronic inflammatory conditions via the inhibition of nuclear factor-kappa B (NF-${\kappa}B$) activation, which results in the suppression of cyclooxygenase-2 (COX-2) expression. However, the mechanisms as to how ginger extracts mediate their health effects are largely unknown. Toll-like receptors (TLRs) trigger anti-microbial innate immune responses, recognizing conserved microbial structural molecules that are known as pathogen-associated molecular patterns. All TLR signaling pathways culminate in the activation of NF-${\kappa}B$. The activation of NF- ${\kappa}B$ leads to the induction of inflammatory gene products, including cytokines and COX-2. This study reports the biochemical evidence that 6-shogaol, an active compound in ginger, inhibits NF-${\kappa}B$ activation and COX-2 expression induced by TLR2, TLR3, and TLR4 agonists. Furthermore, 6-shogaol inhibited NF-${\kappa}B$ activation induced by the following downstream signaling components of the TLRs: MyD88, $IKK{\beta}$, and p65. These results imply that ginger can modulate immune responses that could potentially modify the risk of many chronic inflammatory diseases.

Fructose 1.6-diphosphate Prevents Cyclooxygenase-2 and Matrix Metalloproteinases Expression by Inhibition of UVB-induced Signaling Cascades in HaCaT Keratinocytes (인체각질형성세포에서 Fructose 1,6-diphosphate의 자외선에 의해 유도되는 Cyclooxygenase-2 and Matrix Metalloproteinases의 발현억제기전)

  • Soo Mi, Ahn;Ji Hyun, Kim;Byeong Gon, Lee;Soo Hwan, Lee;Ih Seoup, Chang
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.2
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    • pp.247-251
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    • 2004
  • UV radiation exerts various influences in the skin, including photoaging and inflammation (1). The MMPs (Matrix metalloproteinases), which are induced by UV irradiation, can degrade matrix proteins, and these results in a collagen deficiency in photodamaged skin that leads to skin wrinkling. It has been known that the production of PGE$_2$ stimulates MMPs expression, and inhibits procollagen (2). Thus, it is possible that the induction of MMPs and the inhibition of matrix protein synthesis by UV -induced PGE$_2$ may play some role in UV-induced collagen deficiency in photoaged skin. Fructose-1,6-diphosphate (FDP), a glycolytic metabolite, is reported to have cytoprotective effects against ischemia and postischemic reperfusion injury of brain and heart, presumably by augmenting anaerobic carbohydrate metabolism (3). And also, FDP significantly prevent skin aging by decreasing facial winkle compared with vehicle alone after 6 months of use. We studied the mechanism of anti-aging effect of FDP on UVB-irradiated HaCaT keratinocyte model. FDP has protective role in UVB injured keratinocyte by attenuating prostaglandin E$_2$ (PGE$_2$) production and COX-2 expression. And FDP also suppressed UVB-induced MMP-2 expression. Further, to delineate the inhibition of UVB-induced COX-2 and MMPs expression with cell signaling pathways, treatment of FDP to HaCaT keratinocytes resulted in marked inhibition of UVB-induced phosphorylation of ERK1/2, JNK. It also prevents UV induced NFB translocation, which are activated by cellular inflammatory signal. Our results indicate that FDP has protecting effects in UV-injured skin aging by decreasing UVB-induced COX-2 and MMPs expression, which are possibly through blocking UVB-induced signal cascades.

Eupatorium chinensis var. simplicifolium Root Extract Inhibits the Lipopolysaccharide-Induced Inflammatory Response in Raw 264.7 Macrophages by Inhibiting iNOS and COX-2 Expression (Raw 264.7 대식세포에서 등골나물 뿌리 추출물의 염증반응 조절 분자 iNOS와 COX-2 발현 억제 효과)

  • Lee, Jin-Ho;Kim, Dae-Hyun;Shin, Ji-Won;Park, Sae-Jin;Kim, Yoon-Suk;Shin, Yu-Su;Yu, Ji-Yeon;Kim, Tack-Joong
    • Journal of Life Science
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    • v.22 no.9
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    • pp.1137-1144
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    • 2012
  • Inflammation is a host defense mechanism that is activated in response to harmful substances or pathogens. However, an excessive inflammatory response is a problem in itself. Macrophages secrete inflammatory mediators such as nitric oxide (NO) or cytokines through various pathways such as the nuclear factor kappa B (NF-${\kappa}B$)-activated pathway after recognizing pathogen-like lipopolysaccharides (LPSs). In this study, anti-inflammatory effects of Eupatorium chinensis var. simplicifolium (EUC) extracts were investigated using LPS-stimulated RAW 264.7 macrophages. The EUC root extract significantly reduced NO production, inducible nitric oxide synthase (iNOS) expression, and cyclooxygenase-2 expression in a concentration-dependent manner. In addition, the EUC root extract reduced phosphorylation of mitogen-activated protein kinases and protein kinase B, which is upstream of NF-${\kappa}B$. The EUC root extract also reduced the degradation of inhibitory kappa B. These results indicate that EUC root extract exerts anti-inflammatory effects, which are mediated by inhibition of iNOS expression and the NF-${\kappa}B$ pathway.

Anti-inflammatory effect of naringenin-7-O-phosphate in LPS-induced RAW 264.7 cells (LPS로 유도된 RAW 264. 7 대식세포에서 Naringenin-7-O-phosphate의 항염증 활성)

  • Hyehyun Hong;Tae-Jin Park;Byeong Min Choi;Yu-Jung Yi;Seung-Young Kim
    • Journal of Applied Biological Chemistry
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    • v.66
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    • pp.46-52
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    • 2023
  • The most abundant flavanone of grapefruits, naringenin (NN), is well known for its hepatoprotective, anti-lipid peroxidation and anti-carcinogenic effects. We generated three derivatives from NN using this technique in previous studies. Among them, it was confirmed that naringenin-7-O-phosphate (N7P), whose biological and physicochemical properties were not reported, showed a water solubility 45 times higher than that of NN. Therefore, in this study, the anti-inflammatory activity was evaluated in RAW 264.7 cells to investigate the potential physiological activity of N7P. As a result, N7P showed nitric oxide (NO) inhibitory activity at concentrations that did not show toxicity. In addition, prostaglandin E2 (PGE2) showed significant inhibitory activity from the lowest concentration of 12.5 μM and showed increased inhibitory activity compared to NN. In addition, as a result of western blot, N7P showed increased cyclooxygenase-2 (COX-2) inhibitory activity than NN, and effectively inhibited NO and PGE2 by significantly inhibiting their expression pathways. N7P also inhibited inflammatory cytokines, including tumor necrosis factor-α, interleukin-6. Based on these results, we propose that N7P can be used as a potent antiinflammatory agent.

Alternative Mechanism of Aspirin in Anti-Thrombotic Therapy: Inhibition of Thrombin Activatable Fibrinolysis Inhibitor

  • An, Seong-Soo A.;Greenfield, Robert S.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.3048-3054
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    • 2012
  • The use of aspirin is widely recommended for the prevention of heart attacks owing to its ability to inhibit platelet activation by irreversibly blocking cyclooxygenase 1. However, aspirin also affects the fibrinolytic and hemostatic pathways by mechanisms that are not well understood, causing severe hemorrhagic complications. Here, we investigated the ability of aspirin and aspirin metabolites to inhibit thrombin-activatable fibrinolysis inhibitor (TAFI), the major inhibitor of plasma fibrinolysis. TAFI is activated via proteolytic cleavage by the thrombin-thrombomodulin complex to TAFIa, a carboxypeptidase B-like enzyme. TAFIa modulates fibrinolysis by removing the C-terminal arginine and lysine residues from partially degraded fibrin, which in turn inhibits the binding of plasminogen to fibrin clots. Aspirin and its major metabolites, salicylic acid, gentisic acid, and salicyluric acid, inhibit TAFIa carboxypeptidase activity. Salicyluric acid effectively blocks activation of TAFI by thrombin-thrombomodulin; however, salicylates do not inhibit carboxypeptidase N or pancreatic carboxypeptidase B. Aspirin and other salicylates accelerated the dissolution of fibrin clots and reduced thrombus formation in an in vitro model of fibrinolysis. Inhibition of TAFI represents a novel hemostatic mechanism that contributes to aspirin's therapy-associated antithrombotic activity and hemorrhagic complications.