• BMB Reports
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• 제48권3호
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• pp.172-177
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• 2015

Upregulation of pro-inflammatory mediators contributes to ${\beta}$-cell destruction and enhanced infiltration of immune cells into pancreatic islets during development of type 1 diabetes mellitus. In this study, we examined the regulatory effects and the mechanisms of action of celastrol against cytotoxicity and pro-inflammatory immune responses in the RINm5F rat pancreatic ${\beta}$-cell line stimulated with a combination of interleukin-1 beta, tumor necrosis factor-alpha, and interferon-${\gamma}$. Celastrol significantly restored cytokine-induced cell death and significantly inhibited cytokine-induced nitric oxide production. In addition, the protective effect of celastrol was correlated with a reduction in pro-inflammatory mediators, such as inducible nitric oxide synthase, cyclooxygenase-2, and CC chemokine ligand 2. Furthermore, celastrol significantly suppressed cytokine-induced signaling cascades leading to nuclear factor kappa B (NF-${\kappa}B$) activation, including $I{\kappa}B$-kinase (IKK) activation, $I{\kappa}B$ degradation, p65 phosphorylation, and p65 DNA binding activity. These results suggest that celastrol may exert its cytoprotective activity by suppressing cytokine-induced expression of pro-inflammatory mediators by inhibiting activation of NF-${\kappa}B$ in RINm5F cells.

• Preventive Nutrition and Food Science
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• 제17권1호
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• pp.22-28
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• 2012

Melaleuca leucadendron L. has been used as a tranquilizing, sedating, evil-dispelling and pain-relieving agent. We examined the effects of M. leucadendron L. extracts on oxidative stress and inflammation. M. leucadendron L. was extracted with methanol (MeOH) and then fractionated with chloroform ($CHCl_3$) and butanol (BuOH). Antioxidant activity of the MeOH extract and BuOH fraction were higher than that of both ${\alpha}$-tocopherol and butyrated hydroxytoluene (BHT). Total phenol content in the extracts of M. leucadendron L., especially the BuOH fraction, well correlated with the antioxidant activity. The anti-inflammatory activity of BuOH extracts were investigated by lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) production, and cyclooxygenase-2 (COX-2) expression in RAW 264.7 macrophages. The BuOH fraction significantly inhibited LPS-induced NO and $PGE_2$ production. Furthermore, BuOH extract of M. leucadendron L. inhibited the expression of COX-2 and iNOS protein without an appreciable cytotoxic effect on RAW264.7 cells. The extract of M. leucadendron L. also suppressed the phosphorylation of inhibitor ${\kappa}B{\alpha}$ ($I{\kappa}B{\alpha}$) and its degradation associated with nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activation. Furthermore, BuOH fraction inhibited LPS-induced NF-${\kappa}B$ transcriptional activity in a dose-dependent manner. These results suggested that M. leucadendron L. could be useful as a natural antioxidant and anti-inflammatory resource.

• Biomolecules & Therapeutics
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• 제21권2호
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• pp.146-152
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• 2013

This study examined the total polyphenol content of eight wild edible plants from Ethiopia and their effect on NO production in Raw264.7 cells. Owing to its relatively high polyphenol concentration and inhibition of NO production, the methanol extract of Adansonia digitata L. leaf (MEAD) was subjected to detailed evaluation of its antioxidant and anti-inflammatory effects. Antioxidant effects were assessed by measuring free-radical-scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and oxygen-radical-absorbance capacity (ORAC) assays, while anti-inflammatory effects were assessed by measuring inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. In the ORAC assay, MEAD was 10.2 times more potent than vitamin C at eliminating peroxyl radicals. In DPPH assay, MEAD also showed a strong ROS scavenging effect. MEAD significantly inhibited iNOS activity ($IC_{50}=28.6{\mu}g/ml$) of LPS-stimulated Raw264.7 cells. We also investigated the relationship between iNOS expression and nuclear factor kappa B (NF-${\kappa}B$) activation. MEAD inhibited $I{\kappa}B{\alpha}$ degradation and NF-${\kappa}B$ translocation from the cytosol to the nucleus in LPS-induced RAW264.7 cells without significant cytotoxic effects, as confirmed by MTT assay. These results suggest that MEAD inhibits anti-inflammatory iNOS expression, which might be related to the elimination of peroxyl radicals and thus the inhibition of $I{\kappa}B{\alpha}$-mediated NF-${\kappa}B$ signal transduction.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2909-2914
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• 2015

Objective: To investigate the protective effect of quercetin on radiation induced lung injury (RILI) and related mechanisms. Materials and Methods: Mice treated with radiation and/or quercetin were sacrificed at 1-8 weeks after irradiation under anesthesia. Lung tissues were collected for histological examination. Immunohistochemistry (IHC) and Western blotting were performed to detect the protein expression of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) and Mitogen-activated protein kinases (MAPK) pathway. Results: Hematoxylin and eosin (HE) staining showed that radiation controls displayed more severe lung damage than quercetin groups, either high or low dose. Results of IHC and Western blotting demonstrated the expression level of $NF-{\kappa}B$ to be decreased and that of an inhibitor of $NF-{\kappa}B$ ($I{\kappa}b-{\alpha}$) to be increased by the quercetin intervention compared with the radiation control group. Numbers of JNK/SAPK, p38 and p44/p42 positive inflammatory cells were decreased in the radiation+quercetin injection group (P<0.05). Conclusions: Quercetin may play a radio-protective role in mice lung via suppression of $NF-{\kappa}B$ and MAPK pathways.

• The Korean Journal of Physiology and Pharmacology
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• 제19권5호
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• pp.441-449
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• 2015

Flavonoids are plant pigments that have been demonstrated to exert various pharmacological effects including anti-cancer, anti-diabetic, anti-atherosclerotic, anti-bacterial, and anti-inflammatory activities. However, the molecular mechanisms in terms of exact target proteins of flavonoids are not fully elucidated yet. In this study, we aimed to evaluate the anti-inflammatory mechanism of scutellarein (SCT), a flavonoid isolated from Erigeron breviscapus, Clerodendrum phlomidis and Oroxylum indicum Vent that have been traditionally used to treat various inflammatory diseases in China and Brazil. For this purpose, a nitric oxide (NO) assay, polymerase chain reaction (PCR), nuclear fractionation, immunoblot analysis, a kinase assay, and an overexpression strategy were employed. Scutellarein significantly inhibited NO production in a dose-dependent manner and reduced the mRNA expression levels of inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-${\alpha}$ in lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, SCT also dampened nuclear factor (NF)-${\kappa}B$-driven expression of a luciferase reporter gene upon transfection of a TIR-domain-containing adapter-inducing interferon-${\beta}$ (TRIF) construct into Human embryonic kidney 293 (HEK 293) cells; similarly, NF-${\kappa}B$ nuclear translocation was inhibited by SCT. Moreover, the phosphorylation levels of various upstream signaling enzymes involved in NF-${\kappa}B$ activation were decreased by SCT treatment in LPS-treated RAW264.7 cells. Finally, SCT strongly inhibited Src kinase activity and also inhibited the autophosphorylation of overexpressed Src. Therefore, our data suggest that SCT can block the inflammatory response by directly inhibiting Src kinase activity linked to NF-${\kappa}B$ activation.

• Biomolecules & Therapeutics
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• 제24권5호
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• pp.543-551
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• 2016

This study was designed to evaluate the pharmacological effects of Vaccinium bracteatum Thunb. methanol extract (VBME) on microglial activation and to identify the underlying mechanisms of action of these effects. The anti-inflammatory properties of VBME were studied using lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. We measured the production of nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase (COX)-2, prostaglandin $E_2$ ($PGE_2$), tumor necrosis factor-alpha (TNF-${\alpha}$), interleukin-1 beta (IL-$1{\beta}$), and interleukin-6 (IL-6) as inflammatory parameters. We also examined the effect of VBME on intracellular reactive oxygen species (ROS) production and the activity of nuclear factor-kappa B p65 (NF-${\kappa}B$ p65). VBME significantly inhibited LPS-induced production of NO and $PGE_2$ and LPS-mediated upregulation of iNOS and COX-2 expression in a dose-dependent manner; importantly, VBME was not cytotoxic. VBME also significantly reduced the generation of the pro-inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. In addition, VBME significantly dampened intracellular ROS production and suppressed NF-${\kappa}B$ p65 translocation by blocking $I{\kappa}B-{\alpha}$ phosphorylation and degradation in LPS-stimulated BV2 cells. Our findings indicate that VBME inhibits the production of inflammatory mediators in BV-2 microglial cells by suppressing NF-${\kappa}B$ signaling. Thus, VBME may be useful in the treatment of neurodegenerative diseases due to its ability to inhibit inflammatory mediator production in activated BV-2 microglial cells.

• 대한한방부인과학회지
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• 제21권1호
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• pp.39-54
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• 2008

Purpose: The purpose of this study was to investigate the anti-inflammatory effects of the water extract of Omisodokeum (OMSDE) on peritoneal macrophages, Methods: To verify the anti-inflammatory mechanism of OMSDE, the activation of nuclear $factor-{\kappa}B$ $(NF-{\kappa}B)$ and the phosphorylation of MAPK were examined. Results: The extract of OMSDE suppressed the production of LPS-induced nitric oxide (NO), tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\beta}$, IL-6 and IL-12 in the macrophages. OMSDE inhibited the degradation of inhibitory ${\kappa}B-{\alpha}$ $(I{\kappa}B-{\alpha})$ and it suppressed the activation of extracellular signal-regulated kinase (ERK 1/2) but didn't inhibit c-Jun N-terminal kinase (JNK) and p38, indicating that OMSDE may inhibit the pro-inflammatory cytokine production process by inhibiting the activation of $NF-{\kappa}B$ and ERK 1/2. Furthermore, OMSDE inhibited the production of interferon $(IFN)-{\beta}$ but didn't inhibit of $IFN-{\alpha}$ in the LPS-stimulated macrophages through the down-regulation of interferon regulatory factor (IRF)-1 and IRF-7. The Oral administration of OMSDE inhibited LPS-induced endotoxin shock and the production of $TNF-{\alpha}$ in serum but didn't inhibit of $IL-1{\beta}$ and IL-6. Conclusion: These results suggest that OMSDE may be effective in the prevention and treatment of inflammatory diseases.

• Advances in Traditional Medicine
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• 제10권3호
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• pp.155-164
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• 2010

Lycii fructus is the fruit of Lycium chinense Miller and is part of the Solanaceae family. Lycii fructus produces various effects such as hypotensive, hypoglycemic, anti-pyretic, and anti-stress activities. Lycii fructus is known to contain betaine, carotene, nicotinic acid, zeaxanthin, and cerebroside. In the present study, the effects of Lycii fructus aqueous extract on lipopolysaccharide (LPS)-induced inflammation in murine raw 264.7 macrophage cells were investigated. In this study we utilized the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcriptionpolymerase chain reaction (RT-PCR), Western blotting, and nitric oxide (NO) detection. Lycii fructus aqueous extract suppressed NO production by inhibiting the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-$\alpha$) mRNA and iNOS protein in murine raw 264.7 macrophage cells. Also, Lycii fructus aqueous extract suppressed the activation of nuclear factor-kappa B (NF-${\kappa}B$) in the nucleus. These results demonstrated that Lycii fructus aqueous extract causes an anti-inflammatory effect that was likely produced by the suppression of iNOS expression through the down-regulation of NF-$\hat{e}B$ binding activity.

• BMB Reports
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• 제42권6호
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• pp.380-386
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• 2009

In neurodegenerative diseases, such as Alzheimer' and Parkinson', microglial cell activation is thought to contribute to CNS injury by producing neurotoxic compounds. Prothrombin and kringle-2 increase levels of NO and the mRNA expression of iNOS, IL-1$\beta$, and TNF-$\alpha$ in microglial cells. In contrast, the human prothrombin kringle-2 derived peptide NSA9 inhibits NO release and the production of pro-inflammatory cytokines such as IL-1$\beta$, TNF-$\alpha$, and IL-6 in LPS-activated EOC2 microglia. In this study, we investigated the anti-inflammatory effects of NSA9 in human prothrombin- and kringle-2-stimulated EOC2 microglia. Treatment with 20-100 ${\mu}M$ of NSA9 attenuated both prothrombin- and kringle-2-induced microglial activation. NO production induced by MAPKs and NF-$\kappa$B was similarly reduced by inhibitors of ERK (PD98059), p38 (SB203580), NF-$\kappa$B (N-acetylcysteine), and NSA9. These results suggest that NSA9 acts independently as an inhibitor of microglial activation and that its effects in EOC2 microglia are not influenced by the presence of kringle-2.

• Parasites, Hosts and Diseases
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• 제47권3호
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• pp.205-212
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• 2009

Trichomonas vaginalis commonly causes vaginitis and perhaps cervicitis in women and urethritis in men and women. Macrophages are important immune cells in response to T. vaginalis infection. In this study, we investigated whether human macrophages could be involved in inflammation induced by T. vaginalis. Human monocyte-derived macrophages (HMDM) were co-cultured with T. vaginalis. Live, opsonized-live trichomonads, and T. vaginalis Iysates increased proinflammatory cytokines, such as TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 by HMDM. The involvement of nuclear factor (NF)-${\kappa}B$ signaling pathway in cytokine production induced by T. vaginalis was confirmed by phosphorylation and nuclear translocation of p65 NF-${\kappa}B$. In addition, stimulation with live T. vaginalis induced marked augmentation of nitric oxide (NO) production and expression of inducible NO synthase (iNOS) levels in HMDM. However, trichomonad-induced NF-${\kappa}B$ activation and TNF-${\alpha}$ production in macrophages were significantly inhibited by inhibition of iNOS levels with L-NMMA (NO synthase inhibitor). Moreover, pretreatment with NF-${\kappa}B$ inhibitors (PDTC or Bay11-7082) caused human macrophages to produce less TNF-${\alpha}$. These results suggest that T. vaginalis stimulates human macrophages to produce proinflammatory cytokines, such as IL-1, IL-6, and TNF-${\alpha}$, and NO. In particular, we showed that T. vaginalis induced TNF-${\alpha}$ production in macrophages through NO-dependent activation of NF-${\kappa}B$, which might be closely involved in inflammation caused by T. vaginalis.