• Korean Journal of Clinical Laboratory Science
• /
• v.53 no.2
• /
• pp.158-164
• /
• 2021

Hypertriglyceridemia is the main risk factor for atherosclerosis. It is reported that triglyceride (TG) induces macrophage cell death, and is involved in the formation of plaques and development of atherosclerosis. We previously reported that TG-induced cell death of macrophages is mediated via pannexin-1 activation, which increases the extracellular ATP and subsequent increase in potassium efflux, thereby activating the caspase-2/caspase-1/apoptotic caspases, including the caspase-8 pathway. Contrarily, some studies have reported that caspase-8 is an upstream molecule of caspase-1 and caspase-2 in several cellular processes. Therefore, this study was undertaken to investigate whether caspase-8 influences its upstream molecules in TG-stimulated macrophage cell death. We first confirmed that caspase-8 induces caspase-3 activation and poly ADP-ribose polymerase (PARP) cleavage in TG-treated macrophages. Next, we determined that the inhibition of caspase-8 results in reduced caspase-1 and -2 activity, which are upstream molecules of caspase-8 in TG-induced cell death of macrophages. We also found that ATP treatment restores the caspase-8 inhibitor-induced caspase-2 activity, thereby implying that caspase-8 affects the upstream molecules responsible for increasing the extracellular ATP levels in TG-induced macrophage cell death. Taken together, these findings indicate that caspase-8 potentiates the TG-induced macrophage cell death by activating its upstream molecules.

• Molecules and Cells
• /
• v.23 no.1
• /
• pp.23-29
• /
• 2007

Cyclic AMP-responsive element binding protein (CREB) is known to be associated with angiogenesis. In the present study we investigated the possible role of CREB in the expression of vascular endothelial growth factor (VEGF) by mouse macrophages. Over-expression of CREB increased VEGF secretion by cells of the RAW264.7 mouse macrophage cell line. It also increased the promoter activity of a mouse reporter driven by the VEGF promoter, while a dominant negative CREB (DN-CREB) abrogated the activity, suggesting that CREB mediates VEGF transcription. Forskolin, an adenylyl cyclase activator, stimulated VEGF transcription, and the PKA inhibitor H89 abolished this effect. IFN-${\gamma}$, a potent cytokine, stimulated VEGF expression only in part through the PKA-CREB pathway. These results indicate that PKA phosphorylates CREB and so induces VEGF gene expression. An analysis of mutant promoters revealed that one of the putative CREB responsive elements (CREs), at -399 ~ -388 in the promoter, is critical for CREB-mediated VEGF promoter activity, and the significance of this CRE was confirmed by chromatin immunoprecipitation assays.

• Korean Journal of Pharmacognosy
• /
• v.41 no.2
• /
• pp.122-129
• /
• 2010

Mistletoe (Viscum album) is a common name for many species of semi-parasitic plants which grow on deciduous trees all over the world. In this study, the immunomodulatory activity of the water-extract of Korean mistletoe fruits (KMFWE), was investigated on murine peritoneal macrophages. The culture supernatants of KMF-WE-stimulated murine peritoneal macrophages showed the increased production of IFN-$\gamma$, IL-$1{\beta}$ and TNF-$\alpha$, in a dose-dependent manner. KMF-WE also induced chemokine production from murine peritoneal macrophages such as RANTES, MCP-1, MIP-$1{\alpha}$ and MIP-$1{\beta}$, as well as nitric oxide (NO) production, in a dose-dependent manner. The gel filtration fraction revealed F-1, which is the early-eluted and high molecular weight product, is the major fraction of KMF-WE to activate the murine peritoneal macrophage to induce cytokines, chemokines and NO. The nature of F-1 fraction needs to be examined in detail in further studies to define the regulatory mechanisms of cytokine or chemokine induction by KMF-WE on macrophages. These results suggest that KMF-WE possess a potent immunostimulant activity and can be a promising candidate available for development of immunomodulators.

• Korean Journal of Pharmacognosy
• /
• v.37 no.2 s.145
• /
• pp.74-80
• /
• 2006

We investigated the anti-inflammatory activities of unripe fruit of Citrus grandis Osbeck growing at Jeju Island, through the evaluation of their inhibitory effect on the production of inflammatory markers (IL-6, iNOS, COX, TARC and MDC) in RAW264.7 murine macrophage cells and HaCaT human keratinocyte cells. Among the sequential solvent fractions obtained from crude extract, hexane and chloroform $(CHCI_3)$ fractions showed potential inhibitory activity on the mRNA expressions of IL-6, iNOS and COX-2 at the concentration of $100\;{\mu}g/ml$ in RAW264.7 cells. Also, EtOAc fraction showed inhibitory activity on the thymus and activation-regulated chemokine (TARC)/CCL17 and macrophage-derived chemokine (MDC)/CCL22 at the concentration of $50\;{\mu}g/ml$ in HaCaT cells. These results suggest that the unripe fruit of C. grandis may have anti-inflammatory activity through the suppression of inflammatory markers (IL-6, iNOS, COX, TARC and MDC).

• The Korean Journal of Physiology and Pharmacology
• /
• v.18 no.1
• /
• pp.79-86
• /
• 2014

Hydroxycinnamic acids have been reported to possess numerous pharmacological activities such as antioxidant, anti-inflammatory, and anti-tumor properties. However, the biological activity of 1-p-coumaroyl ${\beta}$-D-glucoside (CG), a glucose ester derivative of p-coumaric acid, has not been clearly examined. The objective of this study is to elucidate the anti-inflammatory action of CG in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. In the present study, CG significantly suppressed LPS-induced excessive production of pro-inflammatory mediators such as nitric oxide (NO) and $PGE_2$ and the protein expression of iNOS and COX-2. CG also inhibited LPS-induced secretion of pro-inflammatory cytokines, IL-$1{\beta}$ and TNF-${\alpha}$. In addition, CG significantly suppressed LPS-induced degradation of $I{\kappa}B$. To elucidate the underlying mechanism by which CG exerts its anti-inflammatory action, involvement of various signaling pathways were examined. CG exhibited significantly increased Akt phosphorylation in a concentration-dependent manner, although MAPKs such as Erk, JNK, and p38 appeared not to be involved. Furthermore, inhibition of Akt/PI3K signaling pathway with wortmannin significantly, albeit not completely, abolished CG-induced Akt phosphorylation and anti-inflammatory actions. Taken together, the present study demonstrates that Akt signaling pathway might play a major role in CG-mediated anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells.

• Toxicological Research
• /
• v.26 no.1
• /
• pp.37-46
• /
• 2010

This study aimed to elucidate anti-inflammatory activities from extracts of Asterina pectinifera on nitric oxide (NO) production, TNF-${\alpha}$ and IL-6 release in lipopolysaccharide (LPS)-stimulated murine macrophage cell, RAW264.7. We prepared the methanolic extracts (60-MAP, 70-MAP, 80-MAP and 90-MAP), aqueous extract (W-AP) and functional bioactive compound fraction (He-AP and EA-AP) from Asterina pectinifera according to extract method. The 60-MAP, 70-MAP, 80-MAP, 90-MAP and W-AP were significantly suppressed LPS-induced production NO, TNF-${\alpha}$ and IL-6 secretion in a concentration-dependent manner (P < 0.05). Especially, 80-MAP by extracted 80% methanol had the strongest activity in reduction of inflammatory mediators among these extracts. Indeed, to identify active fraction, which contained potential bioactive compounds, from 80-MAP of Asterina pectinifera, we tested anti-inflammatory activity of the He-AP or the EA-AP. The He-AP was next extracted from 80-MAP and the EA-AP were extracted from the other methanol layer except the He-AP. The EA-AP demonstrated a strong anti-inflammatory effect through its ability to reduce NO production and it also inhibited the production of proinflammatory cytokines such as IL-6 and TNF-${\alpha}$ at low concentration. These results suggested that the methanolic extract from Asterina pectinifera had the potential inhibitory effects on the production of these inflammatory mediators.

• The Journal of Korean Medicine
• /
• v.28 no.4
• /
• pp.27-41
• /
• 2007

Aim : This study aimed at elucidating the effects of Inonotus obliquus on anti-tumor effects in vivo and immune-based characterization of the mushroom as a potential candidate for cancer remedy. Methods : To investigate the immunomodulatory effects of Inonotus obliquus, we investigated macrophage functions and NK cell activities through the measurement of NO production of macrophage, NK cell cytotoxicity and expressions of cytokines and genes regulating immune responses, in addition to pulmonary metastasis model in vivo. Results : Inonotus obliquus showed general cytotoxicity at high concentrations over the 100 ${\mu}g/m{\ell}$ on the both of normal and cancer cell lines. Inonotus obliquus showed both inhibitory and promotive effects on pulmonary colonization of CT-26 cell depending on period or route of administration in vivo. Conclusion : From these results, it cannot be concluded that Inonotus obliquus has cancer-specific activity. Furthermore, Inonotus obliquus has the provability to show adverse effects differently according to the concentration and the method of administration.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.2
• /
• pp.247-255
• /
• 2006

Yeast cell wall matrix particles are composed entirely of mannoprotein and ${\beta}-glucan$. The mannoproteins of yeast cell wall can systemically enhance the immune system. We previously purified and analyzed alkali-soluble ${\beta}-glucans$ [${\beta}$-(1,3)- and ${\beta}$-(1,6)-glucans] [10]. In the present study, a wild-type strain was first mutagenized with ultraviolet light, and the cell wall mutants were then selected by treatment with 1.0 mg/ml laminarinase (endo-${\beta}$-(1,3)-D-glucanase). Mannoproteins of Saccharomyces cerevisiae were released by laminarinase, purified by concanavalin-A affinity and ion-exchange chromatography. The results indicated that the mutants yielded 3-fold more mannoprotein than the wild-type. The mannoprotein mass of mutant K48L3 was 2.25 mg/100 mg of yeast cell dry mass. Carbohydrate analysis revealed that they contained mannose, glucose, and N-acetylglucosamine. Saccharomyces cerevisiae cell wall components, mannoproteins, are known to interact with macrophages through receptors, thereby inducing release of tumor necrosis factor alpha ($TNF-{\alpha}$) and nitric oxide. Mannoprotein tractions in the present study had a higher macrophage activity of secretion of $TNF-{\alpha}$ and nitric oxide and direct phagocytosis than positive control ($1{\mu}g$ of lipopolysaccharide). In particular, F1 and F3 fractions in mannoproteins of K48L3 enhanced and upregulated the activity of nitric oxide secretion and macrophage phagocytosis by approximately two- and four-fold, respectively.

• Toxicological Research
• /
• v.27 no.2
• /
• pp.77-83
• /
• 2011

The objective of this study was to evaluate and compare the antitumor activity of different solvent fractions (ethanol, dichloromethane, ethyl acetate, butanol and water) of the Auricularia auricula-judae 70% ethanol extract on the P388D1 macrophage and sarcoma 180 cells. A dose-dependent antitumor activity of each solvent fraction (from 0.01 mg/ml to 0.3 mg/ml) was shown against both cell types. These cytotoxic effects of all the tested fractions were confirmed on the MTT and SRB assays, without statistical differences each other. $IC_{50}$ value of dichloromethane fraction was 94.2 ${\mu}g/ml$ against sarcoma 180 cells lower than any other solvent fractions. The potent antitumor effect of the dichloromethane (DCM) fraction was also found against solid tumor in BALB/c mice. The splenomegaly and higher splenic index were found in tumor-bearing mice, with the DCM fraction returning to the negative control values. Thus, the results indicated the dichloromethane fraction may have potential ingredients as antitumor candidates.

• Korean Journal of Pharmacognosy
• /
• v.43 no.3
• /
• pp.217-223
• /
• 2012

In the present study, we investigated anti-inflammatory activity of artemisinic acid in HaCaT cells and RAW264.7 cells. Artemisinic acid showed inhibitory activity on macrophage-derived chemokines (MDC) expression, a factor related with atopic dermatitis (AD), in interferon (IFN)-${\gamma}$ and tumor necrosis factor (TNF)-${\alpha}$-stimulated HaCaT cells. In the study on action mechanism, pretreated artemisinic acid reduced the phosphorylation of STAT1 and p38 and the degradation of $I{\kappa}B$ by IFN-${\gamma}$ and TNF-${\alpha}$ stimulations. However, artemisinic acid didn't show the inhibitory activity on LPS-induced inflammatory mediators (NO, $PGE_2$, IL-6) in RAW264.7 cell. These results indicate that artemisinic acid inhibits IFN-${\gamma}$ and TNF-${\alpha}$-induced MDC expression through inhibition of signal factors, STAT1, NF-${\kappa}B$, and p38, in HaCaT keratinocytes.