• Korean Journal of Pharmacognosy
• /
• v.39 no.2
• /
• pp.95-103
• /
• 2008

In the present study, we investigated the anti-inflammatory effects by kaempferol-3-O-${\beta}$-D-sophoroside (KS) isolated from Sophora japonica (Leguminosae) on the lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin ($PGE_2$) production by RAW 264.7 cell line compared with kaempferol. KS significantly inhibited the LPS-induced NO and $PGE_2$ production. Consistent with these observations, KS reduced the LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in a concentration-dependent manner. In addition, the release and the mRNA expression levels of tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and interleukin-6 (IL-6) were also reduced by KS. Moreover, KS attenuated the LPS-induced activation of nuclear factor-kappa B ($NF{-\kappa}B$), a transcription factor necessary for pro-inflammatory mediators, iNOS, COX-2, $TNF-{\alpha}$ and IL-6 expression. These results suggest that the down regulation of iNOS, COX-2, $TNF-{\alpha}$, and IL-6 expression by KS are achieved by the downregulation of $NF{-\kappa}B$ activity, and that is also responsible for its anti-inflammatory effects.

• Biomolecules & Therapeutics
• /
• v.30 no.6
• /
• pp.540-545
• /
• 2022

Betulin is a triterpenoid natural product contained in several medicinal plants including Betulae Cortex. These medicinal plants have been used for controlling diverse inflammatory diseases in folk medicine and betulin showed anti-inflammatory, antioxidative, and anticancer activities. In this study, we tried to examine whether betulin exerts a regulative effect on the gene expression of MUC5AC mucin under the status simulating a pulmonary inflammation, in human airway epithelial cells. Confluent NCI-H292 cells were pretreated with betulin for 30 min and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 h or the indicated periods. The MUC5AC mucin mRNA expression and mucin glycoprotein production were measured by reverse transcription - polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. To elucidate the action mechanism of betulin, effect of betulin on PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was also investigated by western blot analysis. The results were as follows: 1) Betulin significantly suppressed the production of MUC5AC mucin glycoprotein and down-regulated MUC5AC mRNA expression induced by PMA in NCI-H292 cells. 2) Betulin inhibited NF-κB activation stimulated by PMA. Suppression of inhibitory kappa B kinase (IKK) by betulin led to the inhibition of the phosphorylation and degradation of inhibitory kappa B alpha (IκBα), and the nuclear translocation of NF-κB p65. This, in turn, led to the down-regulation of MUC5AC glycoprotein production in NCI-H292 cells. These results suggest betulin inhibits the gene expression of mucin through regulation of NF-kB signaling pathway, in human airway epithelial cells.

• International Journal of Oral Biology
• /
• v.38 no.1
• /
• pp.37-42
• /
• 2013

Receptor activator of NF-${\kappa}B$ ligand (RANKL) is an essential cytokine for osteoclast differentiation, activation and survival. T lymphocytes such as $T_{17}$ cells, a subset of T helper cells that produce IL-17, play an important role in rheumatoid arthritic bone resorption by producing inflammatory cytokines and RANKL. It has not yet been clearly elucidated how T cell activation induces RANKL expression. T cell receptor activation induces the activation of nuclear factor of activated T cell (NFAT) and expression of its target genes. In this study, we examined the role of NFAT in T cell activation-induced RANKL expression. EL-4, a murine T lymphocytic cell line, was used. When T cell activation was induced by phorbol 12-myristate 13-acetate (PMA) and ionomycin, RANKL expression increased in a time-dependent manner. In the presence of cyclosporin, an inhibitor of NFAT activation, this PMA/ionomycin-induced RANKL expression was blocked. Overexpression of either NFATc1 or NFATc3 induced RANKL expression. Chromatin immunoprecipitation results demonstrated that PMA/ionomycin treatment induced the binding of NFATc1 and NFATc3 to the mouse RANKL gene promoter. These results suggest that NFATc1 and NFATc3 mediates T cell receptor activation-induced RANKL expression in T lymphocytes.

• Proceedings of the Korea Environmental Mutagen Society Conference
• /
• 2002.05a
• /
• pp.86-86
• /
• 2002

• Biomolecules & Therapeutics
• /
• v.16 no.4
• /
• pp.385-393
• /
• 2008

As an attempt to search for bioactive natural products exerting anti-inflammatory activity, we evaluated the effects of the methanol extract of Polytrichum commune Hedw (PCM) (Polytrichaceae) on lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$) and pro-inflammatory cytokines release in murine macrophage cell line RAW 264.7. PCM potently inhibits the production of NO, $PGE_2$, tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6. Consistent with these results, PCM also concentration-dependently inhibited LPS-induced inducible NO synthase (iNOS) and cyclooxygase (COX)-2 at the protein levels, and iNOS, COX-2, TNF-$\alpha$ and IL-6 at the mRNA levels without an appreciable cytotoxic effect on RAW 264.7 macrophag cells. Furthermore, PCM inhibited LPS-induced nuclear factor-kappa B (NF-$\kappa$B) activation as determined by NF-$\kappa$B reporter gene assay, and this inhibition was associated with a decrease in the nuclear translocation of p65 and p50 NF-$\kappa$B. Taken together, these results suggest that PCM may play an anti-inflammatory role in LPS-stimulated RAW 264.7 macrophages through the inhibitory regulation of iNOS, COX-2, TNF-$\alpha$ and IL-6 via NF-$\kappa$B inactivation.

• Journal of Microbiology
• /
• v.39 no.3
• /
• pp.186-194
• /
• 2001

Scrub typhus, caused by Orientia tsutsugamushi infection, is clinically and histopathologically characterized by local as well as systemic inflammatory reactions, indicating that orientiae induce mechanisms that amplify the inflammatory response. To reveal underlying mechanisms of chemoattraction and activation of responding leukocytes, expression of chemokine and tumor necrosis factor alpha (TNF-$\alpha$) genes in murine peritoneal macrophages after infection with the obligate intracellular bacterium Ο.tsutsugamushi was investigated. The genes that were unregulated included macrophage inflammatory proteins l$\alpha$/$\beta$(MIP-l$\alpha$/$\beta$), MIP-2, monocyte chemoattractant protein 1(MCP-1), RANTES (regulated upon activation, normal T-cell expressed and secreted), gamma-interferon-inducible protein 10(IP-10) and TNF-$\alpha$. Peak expression of these chemokines and TNF-$\alpha$ was observed between 1 and 3 h after infection. These responses returned to or approached baseline preinfection levels 6 h after challenge. Semiquantitative reverse transcription (RT)-PCR analysis revealed dramatic Increases during infection in the steady-state levels of mRNA ceding for the inhibitory subunit of NF-kB (IkB$\alpha$), whose transcription is enhanced by binding of NF-kB within the IkB$\alpha$promoter region. Thus, Ο. tsutsugamushi appears to be a stung inducer of chemokines and TNF-$\alpha$ which may significantly contribute to inflammation and tissue damage observed in scrub typhus by attracting and activating phagocytic leukocytes.

• International Journal of Oral Biology
• /
• v.30 no.4
• /
• pp.135-141
• /
• 2005

Although it has been known that TGF-${\beta}1$ acts as a crucial cofactor in osteoclast differentiation, its mode of action is still unclear. In the present study, we studied the effect of TGF-${\beta}1$ on the differentiation of osteoclast depending on the developmental stages. Murine bone marrow cells were induced to differentiate into mature osteoclasts in the presence of receptor activator of NF-${\kappa}B$ ligand (RANKL) and macrophage colony stimulating factor (M-CSF). In the early stage of the differentiation TRAP(-) mononuclear precursor cells were obtained from nonadherent M-CSF dependent bone marrow cells, which further differentiated into mature osteoclasts. TGF-${\beta}1$ stimulated osteoclast differentiation, which was stronger when cells were stimulated by TGF-${\beta}1$ in the early stage than the later differentiation. TGF-${\beta}1$ increased the expression of RANK and synergistically stimulated RANKL-induced activation of NF-${\kappa}B$ MAP kinase in TRAP(-) mononuclear precursor cells. These results suggest that activation of osteoclast differentiation by TGF-${\beta}1$ may be ascribed to the both increased expression and activation of RANK in the osteoclast differentiation, especially in the early stage of differentiation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.17 no.1
• /
• pp.163-171
• /
• 2004

The flowers of Lonicera japonica Thunb. (Caprifoliaceae) has been used as anti-inflammatory drug in the folk medicine recipe and been proved its anti-inflammatory effect in the oriental medicine. However, the action mechanism of Lonicera japonica that exhibits anti-inflammatory effects has not been determined. Since nitric oxide (NO) is one of the major inflammatory parameter, we studied the effect of aqueous extracts of Lonicera japonica (AELJ) on NO production in lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages. NO and inducible NO synthase (iNOS) level were significantly reduced in LPS-stimulated macrophages by AELJ compared to those without Electrophoretic mobility shift assay (EMSA) indicated that AELJ blocked the activation of nuclear factor kappa B (NF-kB), which was considered to be a potential transcription factor for the iNOS expression. AELJ also blocked the phosphorylation and degradation of inhibitor of kappa B-alpha (IkB-${\alpha}$). Furthermore, IkB kinase alpha (IKK${\alpha}$), which is known to phosphorylate serine residues of IkB directly, is inhibited by AELJ in vivo and in vitro. These results suggest that AELJ could exert its anti-inflammatory actions by suppressing the synthesis of NO through inhibition of NF-kB activity.

• IMMUNE NETWORK
• /
• v.11 no.2
• /
• pp.123-133
• /
• 2011

Background: Mycobacterium tuberculosis (Mtb) heparin binding hemagglutinin (HBHA) is an Ag known to evoke effective host immune responses during tuberculosis infection. However, the molecular basis of the host immune response to HBHA has not been fully characterized. In this study, we examined the molecular mechanisms by which HBHA can induce the expression of proinflammatory cytokines in macrophages. Methods: HBHA-induced mRNA and protein levels of proinflammatory cytokines were determined in bone marrow-derived macrophages (BMDMs) using RT-PCR and ELISA analysis. The roles of intracellular signaling pathways for NF-${\kappa}B$, PI3-K/Akt, and MAPKs were investigated in macrophage proinflammatory responses after stimulation with HBHA. Results: HBHA robustly activated the expression of mRNA and protein of both TNF-${\alpha}$ and IL-6, and induced phosphorylation of NF-${\kappa}B$, Akt, and MAPKs in BMDMs. Both TNF-${\alpha}$ and IL-6 production by HBHA was regulated by the NF-${\kappa}B$, PI3-K, and MAPK pathways. Furthermore, PI3-K activity was required for the HBHA-induced activation of ERK1/2 and p38 MAPK, but not JNK, pathways. Conclusion: These data suggest that mycobacterial HBHA significantly induces proinflammatory responses through crosstalk between the PI3-K and MAPK pathways in macrophages.

• Tuberculosis and Respiratory Diseases
• /
• v.42 no.6
• /
• pp.862-870
• /
• 1995

Background: Oxygen free radicals have generally been considered as cytotoxic agents. On the other hand, recent results suggest that small nontoxic amounts of these radicals may act a role in intracellular signal transduction pathway and many efforts to reveal the role of these radicals as secondary messengers have been made. It is evident that the oxygen radicals are released by various cell types in response to extracellular stimuli including LPS, TNF, IL-1 and phorbol esters, all of which translocate the transcription factor $NF{\kappa}B$ from cytoplasm to nucleus by releasing an inhibitory protein subunit, $I{\kappa}B$. Activation of $NF{\kappa}B$ is mimicked by exposure to mild oxidant stress, and inhibited by agents that remove oxygen radicals. It means the cytoplasmic form of the inducible tanscription factor $NF{\kappa}B$ might provide a physiologically important target for oxygen radicals. At the same time, it is well known that LPS induces the release of oxygen radicals in neutrophil with the activation of $NF{\kappa}B$. From above facts, we can assume the expression of IL-8 and IL-$1{\beta}$ gene by LPS stimulation may occur through the activation of $NF{\kappa}B$, which is mediated through the release of $I{\kappa}B$ by increasing amounts of oxygen radicals. But definitive evidence is lacking about the role of oxygen free radicals in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. We conducted a study to determine whether oxygen radicals act a role in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. Method: Human peripheral blood monocytes were isolated from healthy volunteers. Time and dose relationship of $H_2O_2$-induced IL-8 and IL-$1{\beta}$ mRNA expression was observed by Northern blot analysis. To evaluate the role of oxygen radicals in the expression of IL-8 and IL-$1{\beta}$ mRNA by LPS stimulation, pretreatment of various antioxiants including PDTC, TMTU, NAC, ME, Desferrioxamine were done and Northern blot analysis for IL-8 and IL-$1{\beta}$ mRNA was performed. Results: In PBMC, dose and time dependent expression of IL-8 and IL-$1{\beta}$ mRNA by exogenous $H_2O_2$ was not observed. But various antioxidants suppressed the expression of LPS-induced IL-8 and IL-$1{\beta}$ mRNA expression of PBMC and the suppressive activity was most prominant when the pretreatment was done with TMTU. Conclusion: Oxygen free radical may have some role in the expression of IL-8 and IL-$1{\beta}$ mRNA of PBMC but that radical might not be $H_2O_2$.