• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.17-27
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• 2001

A cell-based assay system for monitoring NF-$textsc{k}$B activity was developed to determine the influence of activated NF-$textsc{k}$B in human HaCaT cells. The pNF-$textsc{k}$B-SEAP-NPT plasmid that permits expression of the secreted alkaline phosphatase (SEAP) reported gene in response to the NF-$textsc{k}$B activity and contains neomycin phosphotransferase (NPT) gene for the geneticin resistance in host cells was constructed and transfected into human keratinocyte cell line HaCaT. Human HaCaT transfectant cells secreted the SEAP enzyme into the culture medium in a time-dependent manner until 72h. NF-$textsc{k}$B activities were measured in the SEAP reporter gene assay using a fluorescent detection method. The treatment of HaCaT cell transfectants with known antioxidants [e.g., N-acetyl-L-cysteine and vitamin C] showed inhibition of NF-$textsc{k}$B activity in a time-and concentration-dependent manner. The phorbol 12-myristate 13-acetate (PMA) known as a stimulator of NF-$textsc{k}$B expression demonstrated that it increased NF-$textsc{k}$B activity in a time- and concentration-dependent manner. This assay system could be used to determine the quantitative measurement of NF-$textsc{k}$B activity in the human skin and allow the screening of anti-inflammatory agents from various synthetic chemicals and natural products for dermatological purpose. Abbrevitions used: NF-$textsc{k}$B, nuclear factor kappa B; I-$textsc{k}$B, Inhibitory kappa B; SEAP, secreted alkaline phosphatase; NPT, neomycin phosphotransferease; PCR, polymerase chain reaction: dNTP, deoxynucleoside triphosphates; DMEM, dulbecco’s modified eagle medium; FBS, fetal bovine serum; PBs, phosphate-buffered saline; MUP, 4-methylumbellifery phosphate; NAC, N-acetyl-L-cysteine; DMSO, dimethyl sulfoxide; PMA, phorbol 12-myristate 13-acetate.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.9-18
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• 2000

Immunological mechanisms involving the release of inflammatory factors by HIV-1 infected microglia in the brain have been implicated in the pathogenesis of HIV dementia (HIVD). Since the regulation of matrix metalloproteinases (MMPs) activity can be influenced by variety of inflammatory mediators, this study was undertaken to look for a correlation between the MMP-9 release and the production of TNF-${\alpha}$ in response to HIV-1 p24 in the human monocyte cell line THP-1 as a model for microglia. First, it was shown that HIV-l core p24 antigen induced THP-1 to secrete MMP-9 in a dose response manner while it elicited a little effect on MMP-2 release in human astroglial cell line T98G. Next, it was found that p24 induced THP-1 to secrete TNF-${\alpha}$ without prior differentiation into macrophages by phorbol myristate acetate (PMA) treatment. Furthermore, anti-TNF-${\alpha}$ neutralizing antibodies significantly blocked p24-induced MMP-9 release in a dose dependent manner. Our data indicate that p24 antigen induces monocytic MMP-9 release by triggering up-regulation of TNF-${\alpha}$ secretion.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.79-86
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• 2001

Recent clinical studies have shown that a high proportion of patients with acute promyelocytic leukemia (APL) achieve complete remission after treatment with all-trans retinoic acid (ATRA). However, most patients who receive continuous treatment with ATRA relapse and develop ATRA-resistant leukemia. Dendritic cells (DCs) are important antigen-presenting cells in the development of antileukemic T-cell responses. In this study, we investigated the strategies to overcome ATRA resistance of APL cells by inducing the differentiation of DCs from human leukemic cell lines for the developtment of adoptive immunotherapy. CD83 was used as a mature DC marker in this study and the expression of CD83 mRNA was determined by RT-PCR method. The promyelocytic leukemic cell line HL-60, B lymphoblast cell lines RPMI 7666 and NC-37 could be induced to dendritic cells in vitro. Treatment of HL-60 with phorbol 12-myristate 13-acetate (PMA) resulted in the expression of myeloid-related DC phenotypes, while treatment of RPMI 7666 with fms-like tyrosine kinase 3 ligand (Flt3-ligand, FL) and treatment of NC-37 with PMA and FL led to the expression of lymphoid-related DC phenotypes. In conclusion, myeloid-related DC phenotypes and lymphoid-related DC phenotypes could be generated from HL-60, NC-37 and RPMI 7666 cell lines, respectively. These DC phenotypes can potentially be used to generate antileukemic T cells in vitro for adoptive immunotherapy.

• Journal of Life Science
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• v.23 no.5
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• pp.650-656
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• 2013

Endothelial protein C receptor (EPCR) plays a pivotal role in augmenting Protein C activation through the thrombin-thrombomodulin complex. EPCR activity is markedly changed by ectodomain cleavage and released as the soluble protein (sEPCR). EPCR shedding is mediated by tumor necrosis factor-${\alpha}$ converting enzyme (TACE). Lycopene found in tomatoes and tomato products has anti-oxidant, anti- cancer and anti-inflammatory effects. However, little is known about the effects of lycopene on EPCR shedding. We investigated this issue by monitoring the effects of lycopene on the phorbol-12-myristate 13-acetate (PMA), tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$ and on the cecal ligation and puncture (CLP)-mediated EPCR shedding. Data showed that lycopene potently inhibited the PMA, TNF-${\alpha}$, IL-$1{\beta}$ and CLP-induced EPCR shedding by suppressing TACE expression. Furthermore, lycopene reduced PMA-stimulated phosphorylation of p38, extracellular regulated kinases (ERK) 1/2 and c-Jun N-terminal kinase (JNK). Given these results, lycopene should be viewed as a candidate therapeutic agent for the treatment of various severe vascular inflammatory diseases via inhibition of the EPCR shedding.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.125-133
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• 1991

In the isolated rabbit mesenteric artery denuded of endothelium, we characterized the identity of the A23187-induced endothelium-dependent relaxing factor (EDRF) released from the endothelium of rabbit aorta, which is distinct from that of acetylcholine-induced relaxing factor. In the normal physiological salt solution (PSS), the dose-response curves to A23187 and acetylcholine were overlapped together. Their effects were also inhibited by methylene blue. Upon application of hypoxanthine and xanthine oxidase into the bath, the phenylephrine-induced precontraction was transiently increased followed by the sustained relaxation. During the burst of hypoxanthine-xanthine oxidase reaction, the $Ca^{++}$ ionophore, A23187 but not acetylcholine was able to cause an immediate relaxation. However, A23187-induced relaxation was not manifested when precontracted by 50 mM $K^+-PSS$. Nevertheless, in the presence of superoxide dismutase, A23187 could produce an immediate relaxation without accompanying the transient contraction as acetylcholine did during the hypoxanthine-xanthine oxidase reaction. On the other hand, acetylcholine-induced relaxation was more sensitively inhibited by phorbol 12-myristate 13-acetate (PMA) than A23187-induced relaxation. Endothelium-independent relaxation to sodium nitroprusside was not affected by PMA. Based on these results it is suggested that both A23187 and acetylcholine cause the methylene blue-inhibitable endothelium-dependent relaxation, and in addition, A23187 may release a stable EDRF which is resistant to superoxide anion and PMA.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.2
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• pp.185-193
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• 1997

The characteristics of $Na^+$-dependent cycloleucine uptake was investigated in OK cells with regard to substrate specificity and regulation by protein kinase C (PKC). Inhibition studies with different synthetic and natural amino acids showed a broad spectrum affinity to neutral amino acids regardless of their different side chains including branched or aromatic, indicating that the $Na^+$-dependent cycloleucine uptake in OK cells is mediated by System $B^o$ or System $B^o$-like transporter rather than the classical System A or ASC. Phorbol 12-myristate 13-acetate (PMA) and phorbol 12,13-dibutyrate, but not $4{\alpha}-PMA$ elicited a time-dependent biphasic stimulation of $Na^+$-dependent cycloleucine uptake, which produced early transient peak at 30 min and late sustained peak at 180min. Both the early and late stimulations by PMA were due to an increase in Vmax and not due to a change in Km. PKC inhibitors blocked both the early and late stimulation by PMA, while protein synthesis inhibitors blocked the late stimulation only. These results suggest the existence and regulation by PKC of System $B^o$ or System $B^o$-like broad spectrum transport system for neutral amino acids in OK cells.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.42-47
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• 1999

Phorbol ester, growth factors activities are mediated by unclear transcription factors, the c-Fos and c-Jun, which can regulate transcriptional activation through specific DNA sites and by forming the transcription factor AP-l, which usually mediates cell proliferation and differentiation signals. We explored effects of Pini Folium extract (API-l) on AP-l activity. Western blot analysis confirmed that API-l decreased levels of c-Fos or c-Jun protein induced by the tumor promoter Phorbol 12-myristate 13-acetate (PMA; 200 nM). Transient transfection assays with a c-fos promoter reporter construct showed that API-l decreased transcription activity by ore than 50~60%. However, treatment of API-l activity studied further. The main substances were fractionated into dichloromethane layer. Futhermore, API-l extract repressed the [$^3H$]-thymidine uptake in C6 glioma cells, indicating that this extract could be included in a new type of modulator in the mitogenesis.

• Molecules and Cells
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• v.23 no.2
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• pp.138-144
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• 2007

Previously we showed that the human GM3 synthase gene was expressed during the induction of megakaryocytic differentiation in human leukemia K562 cells by phorbol 12-myristate 13-acetate (PMA). In this study we found that treatment of PMA-induced K562 cells with $G{\ddot{o}}6976$, a specific inhibitor of PKC, and U0126, an inhibitor of the extracellular signal-regulated kinase (ERK) reduced expression of GM3 synthase, whereas wortmannin, an inhibitor of phosphoinositide 3-kinase (PI3K) did not. Moreover, activation of ERK and cAMP response element binding protein (CREB) was prevented by pretreatment with $G{\ddot{o}}6976$ and U0126. PMA stimulated the promoter activity of the 5'-flanking region from -177 to -83 region of the GM3 synthase gene, and mutation or deletion of a CREB site located around -143 of the promoter reduced PMA-stimulated promoter activity, as did the inhibitors $G{\ddot{o}}6976$ and U0126. Our results demonstrate that induction of GM3 synthase during megakaryocytic differentiation in PMA-stimulated human leukemia K562 cells depends upon the PKC/ERK/CREB pathway.

• Molecular & Cellular Toxicology
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• v.2 no.4
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• pp.223-228
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• 2006

Several plant-derived cannabinoids and endogenous ligands for cannabinoid receptors such as 2-arachidonyl-glycerol have been known to inhibit interleukin-2 (IL-2) expression. In the present study, we utilized arachidonylethanolamide (AEA), a putative endogenous ligand for cannabinoid receptors, to determine whether AEA modulated the expression of IL-2. AEA inhibited phorbol 12-myristate 13-acetate (PMA) plus ionomycin (Io)-induced IL-2 protein secretion and mRNA expression in EL-4 mouse T-cells as determined by ELISA and RT-PCR, respectively. To further characterize the inhibitory mechanism of AEA at the transcriptional level, we performed promoter study for IL-2 gene in PMA/Io-stimulated EL-4 cells. AEA decreased the transcriptional activity of the nuclear factor of activated T-cells (NF-AT) as well as the IL-2 promoter activity. These results suggest that AEA suppresses IL-2 expression and that the inhibition is mediated, at least in part, through the down-regulation of NF-AT.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.958-963
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• 2006

The effect of ginsenosides (GS) on germ cell proliferation was evaluated with a chicken ovarian germ-somatic cell coculture model and the mechanism involving protein kinase C (PKC) pathway was investigated. Ovarian cells were cultured in serum-free McCoy's 5A medium and challenged with GS alone or in combinations with PKC activator (phorbol 12-myristate 13-acetate, PMA) or inhibitor ($H_7$) for 48 h. The number of germ cells was counted and the proliferating cells were identified by immunocytochemistry of proliferating cell nuclear antigen (PCNA). Results showed that GS significantly increased germ cell proliferation and this stimulating effect was further increased by PMA, but inhibited by H7, in a dose-dependent manner. Moreover, GS-elevated PCNA expression and the PCNA -labeling index of germ cells displayed similar changes with the increased numbers of germ cells. These results indicated that GS stimulated proliferation of ovarian germ cells with involvement of the PKC-mediated system.