• Biomedical Science Letters
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• v.26 no.4
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• pp.256-266
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• 2020

Carboxypeptidase D (CPD) is a zinc-dependent protease, which is highly expressed in macrophages, and is thought to participate in inflammatory processes. In the present study, we investigated the possible regulatory effect of all-trans retinoic acid (ATRA), which is an active form of vitamin A and plays a critical regulatory role in both the innate and adaptive immunity, on CPD expression and secretion in human monocytic THP-1 cells. CPD mRNA expression first increased, from a concentration as low as 10 nM ATRA to a maximum level of expression, at 1 μM. ATRA enhanced intracellular CPD expression in a time- and concentration-dependent manner but did not affect cell surface CPD expression. Interestingly, 9-cis-RA did not affect CPD expression. Additionally, an experiment with RAR/RXR selective agonist or antagonists demonstrated that ATRA-induced enhancement of CPD expression was RAR/RXR dependent. ATRA also enhanced CPD secretion from THP-1 cells; however, this enhancement was RAR/RXR-independent. The anti-inflammatory agent dexamethasone reversed ATRA-induced enhancement of CPD expression and secretion. Our results suggest ATRA exerts regulatory effects on expression and secretion of CPD in human monocytes, and ATRA-induced CPD secretion may be associated with inflammatory response.

• Korean Journal of Pharmacognosy
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• v.47 no.3
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• pp.197-203
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• 2016

Decursin is a major component of the root of Angelica gigas(Umbelliferae), which has been traditionally used in Korea as a tonic and to treat anemia, hemiplegia, and women's diseases. The objective of this study is to identify the anti-cancer mechanism induced by decursin on apoptosis of human leukemia and lymphoma cells. Cytotoxicity of decursin on U937, HL-60, MOLT-4, THP-1 cells showed the significant effects. First of all, $IC_{50}$ of decursin on four cell lines was 27.1, 32.4, 17.4, $15.1{\mu}M$, respectively. So $IC_{50}$ in THP-1 cells was the smallest among 4 cell lines treated with decursin($15.1{\mu}M$). In order to understand the apoptosis-mechanism by decursin, we examined the gene expression of bcl-2(anti-apoptotic), bax(pro-apoptotic) and p53(tumor suppressor)after treating the THP-1 cells with decursin(10, 50 and $100{\mu}M$). It was found bcl-2 gene was decreased dose dependently, the expression level of bax gene of THP-1 cells treated with $100{\mu}M$ of decursin was about 3 times higher than those of control, and p53 gene was increased In the same concentration($100{\mu}M$), p53 gene was increased dose dependent manner. In protein express, bcl-2 and p53 protein showed a tendency to decrease. bax was increased about 4 fold. Therefore decursin is a useful chemotherapeutic agent against leukemia.

• International Journal of Oral Biology
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• v.42 no.1
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• pp.17-23
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• 2017

Background: Periodontitis is generally a chronic disorder characterized by the breakdown of tooth-supporting tissues. P. gingivalis, a Gram-negative anaerobic rod, is one of the major pathogens associated with periodontitis. Frequently, P. gingivalis infection leads to cell death. However, the correlation between P. gingivalis-induced cell death and periodontal inflammation remains to be elucidated. Among cell deaths, the death of immune cells appears to play a significant role in inflammatory response. Thus, the aim of this study was to examine P. gingivalis-induced cell death, focusing on autophagy and apoptosis in THP-1 cells. Methods: Human acute monocytic leukemia cell line (THP-1) was used for all experiments. Autophagy induced by P. gingivalis in THP-1 cells was examined by Cyto ID staining. Intracellular autophagic vacuoles were observed by fluorescence microscopy using staining Acridine orange (AO); and 3-methyladenine (3-MA) was used to inhibit autophagy. Total cell death was measured by LDH assay. Cytokine production was measured by an ELISA method. Results: P. gingivalis induced autophagy in an MOI-dependent manner in THP-1 cells, but 3-MA treatment decreased autophagy and increased the apoptotic blebs. P. gingivalis infection did not increase apoptosis compared to the control cells, whereas inhibition of autophagy by 3-MA significantly increased apoptosis in P. gingivalis-infected THP-1 cells. Inhibition of autophagy by 3-MA also increased total cell deaths and inflammatory cytokine production, including $IL-1{\beta}$ and $TNF-{\alpha}$. Conclusion: P. gingivalis induced autophagy in THP-1 cells, but the inhibition of autophagy by 3-MA stimulated apoptosis, leading to increased cell deaths and pro-inflammatory cytokines production. Hence, the modulation of cell deaths may provide a mechanism to fight against invading microorganisms in host cells and could be a promising way to control inflammation.

• BMB Reports
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• v.53 no.12
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• pp.640-645
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• 2020

Suppressors of cytokine signaling (SOCS) exhibit diverse anti-inflammatory effects. Since ROS acts as a critical mediator of inflammation, we have investigated the anti-inflammatory mechanisms of SOCS via ROS regulation in monocytic/macrophagic cells. Using PMA-differentiated monocytic cell lines and primary BMDMs transduced with SOCS1 or shSOCS1, the LPS/TLR4-induced inflammatory signaling was investigated by analyzing the levels of intracellular ROS, antioxidant factors, inflammasome activation, and pro-inflammatory cytokines. The levels of LPS-induced ROS and the production of pro-inflammatory cytokines were notably down-regulated by SOCS1 and up-regulated by shSOCS1 in an NAC-sensitive manner. SOCS1 up-regulated an ROS-scavenging protein, thioredoxin, via enhanced expression and binding of NRF-2 to the thioredoxin promoter. SOCS3 exhibited similar effects on NRF-2/thioredoxin induction, and ROS downregulation, resulting in the suppression of inflammatory cytokines. Notably thioredoxin ablation promoted NLRP3 inflammasome activation and restored the SOCS1-mediated inhibition of ROS and cytokine synthesis induced by LPS. The results demonstrate that the anti-inflammatory mechanisms of SOCS1 and SOCS3 in macrophages are mediated via NRF-2-mediated thioredoxin upregulation resulting in the downregulation of ROS signal. Thus, our study supports the anti-oxidant role of SOCS1 and SOCS3 in the exquisite regulation of macrophage activation under oxidative stress.

• IMMUNE NETWORK
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• v.22 no.4
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• pp.33.1-33.17
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• 2022

Suppressors of cytokine signaling (SOCS) have emerged as potential regulators of macrophage function. We have investigated mechanisms of SOCS3 action on type 2 macrophage (M2) differentiation induced by glucocorticoid using human monocytic cell lines and mouse bone marrow-derived macrophages. Treatment of THP1 monocytic cells with dexamethasone (Dex) induced ROS generation and M2 polarization promoting IL-10 and TGF-β production, while suppressing IL-1β, TNF-α and IL-6 production. SOCS3 over-expression reduced, whereas SOCS3 ablation enhanced IL-10 and TGF-β induction with concomitant regulation of ROS. As a mediator of M2 differentiation, glucocorticoid-induced leucine zipper (GILZ) was down-regulated by SOCS3 and up-regulated by shSOCS3. The induction of GILZ and IL-10 by Dex was dependent on ROS and p38 MAPK activity. Importantly, GILZ ablation led to the inhibition of ROS generation and anti-inflammatory cytokine induction by Dex. Moreover, GILZ knock-down negated the up-regulation of IL-10 production induced by shSOCS3 transduction. Our data suggest that SOCS3 targets ROS- and p38-dependent GILZ expression to suppress Dex-induced M2 polarization.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.140-146
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• 2008

Human cytomegalovirus (HCMV) stimulates the expression of intercellular adhesion molecule (ICAM-l) on the surface of monocytic THP-1 cells. Stimulation of ICAM-l did not require HCMV gene expression since UV-inactivated HCMV (UV-HCMV) was able to induce ICAM-l expression. ICAM-l expression was also stimulated in uninfected THP-l cells which were fed with culture supernatant of HCMV-infected THP-l cells. Co-culture experiment using trans-well insert supported that HCMV-infected THP-l cells secreted some cytokine(s) stimulating ICAM-l expression. The stimulation of ICAM-l by HCMV-infected cell culture supernatant appears to involve $NF-{\kappa}B$ pathway. Culture supernatant from THP-l cells infected with UV-HCMV, whose gene expression was abrogated, failed to stimulate ICAM-l expression on naive THP-l cells. Thus, HCMV gene expression seems to be required in secretion of cytokine(s) stimulating ICAM-l expression.

• Archives of Pharmacal Research
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• v.23 no.1
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• pp.54-58
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• 2000

To elucidate the molecular mechanisms for the suppression of LPS-induced nitric oxide (NO) production by a dehydrocostus lactone (DL) from Saussurea lappa, we examined the preventive effect of this compound on $NF-{\kappa}B$ activation in LPS-treated RAW 264.7 macrophages and U937 human monocytic cells. The results suggest that the suppression of NO production is mediated by the inhibitory action on the i-NOS gene expression through the inactivation of $NF-{\kappa}B$ and this sesquiterpene lactone can act as a pharmacological inhibitor of the $NF-{\kappa}B$ activation.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.796-801
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• 2007

This study was conducted to investigate antioxidant activity and anti-immunological inflammatory effect of Allium victorialis subsp. platyphyllum extracts (AVPEs). Antioxidant activities of AVPEs were determined by free radical scavenging assay and reducing power test. Leaf-part extract had comparatively better antioxidant activity than other-part extracts. Antioxidant activity of extracts had protective effect for human umbilical vein endothelial cells (HUVECs) against superoxide anions secreted from activated neutrophils. Also, we observed AVPEs had inhibitory effects on the adherence of monocytic THP-1 to HUVEC monolayer to the basal level. Inhibitory effect on cell adhesion was caused by suppression of tumor necrosis factor-${\alpha}\;(TNF-{\alpha})-upregulated$ expression of vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin in HUVECs. From these results, we expect to support the evidence of anti-immunological inflammatory effects of Allium victorialis subsp. platyphyllum (AVP) as a Korean traditional pharmaceutical.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.17-21
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• 2022

The present study aimed to determine whether a hemolymph prepared from Antheraea yamamai larvae had the same biological activities using a Bombyx mori hemolymph prior to exposure to lipopolysaccharide (LPS) in order to induce an inflammatory response. The effects of the hemolymph were determined using a reverse transcription-quantitative polymerase chain reaction to assess the expression of pro-inflammatory molecules. The A. yamamai hemolymph exerted anti-inflammatory effects on LPS-activated human monocytic leukemia cells via Toll-like receptor (TLR) 4-mediated suppression, similar to the B. mori hemocyte extract. Treatment with the A. yamamai hemolymph significantly suppressed LPS-induced upregulated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA expression at all tested concentrations compared with the control, similar to the B. mori immune-challenged hemolymph. Finally, the A. yamamai hemolymph, like the B. mori immune-challenged hemolymph, suppressed all of these concentrations in a dose-independent manner. These results demonstrate that the hemolymph of A. yamamai exhibited important biologically active substances. Further in-depth functional studies are required to fully understand the mechanisms underlying the biological activities of wild-type silkworm hemolymphs.

• Biomolecules & Therapeutics
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• v.9 no.1
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• pp.40-45
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• 2001

The activity of taurine transporter is affected by various extracellular stimuli such as ion, hormone and stress. To assess effects of steroid hormones antral cyclosporin A (CsA) on the taurine transporter activity, murine monocytic RAW264.7 cell line was stimulated with dexamethasone (DM), triamcinolone (TA), cortisone (CS), hydrocortisone (HCS), prednisone (PSN), prednisolone (PSL) and methylprednisolone (MPSL) in the presence of 12-0-tetradecanoylphorbol-13-acetate(TPA). Treatment of TPA on the cell line led to significant reduction of taurine transporter activity. However, in case of stimulation of the cells with steroid hormones in the presence of TPA, all of them recovered TPA-induced reduction of the taurine transporter activity. Treatment of the cells with CsA led to significant reduction of the taurine transporter activity. Ionomycin (IM) recovered the reduced taurine transporter activity by CsA, but failed in the presence of EDTA, a calcium chelating agent. These results showed that glucocorticoid hormone recovered TPA-induced reduction of taurine transporter activity and that IM recovered CsA-induced reduction of the transporter activity by increasing intracellular free $Ca^{++}$ concentration.n.