• Tuberculosis and Respiratory Diseases
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• v.86 no.4
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• pp.304-318
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• 2023

Background: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment and significantly contribute to immune evasion. We investigated the effects of CAFs on the immune function of CD4+ and CD8+ T cells in non-small cell lung cancer (NSCLC). Methods: We isolated CAFs and normal fibroblasts (NFs) from tumors and normal lung tissues of NSCLC patients, respectively. CAFs were co-cultured with activated T cells to evaluate their immune regulatory function. We investigated the effect of CAF conditioned medium (CAF-CM) on the cytotoxicity of T cells. CAFs were also co-cultured with activated peripheral blood mononuclear cells and further incubated with cyclooxygenase-2 (COX2) inhibitors to investigate the potential role of COX2 in immune evasion. Results: CAFs and NFs were isolated from the lung tissues (n=8) and lymph nodes (n=3) of NSCLC patients. Immune suppressive markers, such as COX2 and programmed death-ligand 1 (PD-L1), were increased in CAFs after co-culture with activated T cells. Interestingly, CAFs promoted the expression of programmed death-1 in CD4+ and CD8+ T cells, and strongly inhibited T cell proliferation in allogenic and autologous pairs of CAFs and T cells. CAF-CM decreased the cytotoxicity of T cells. COX2 inhibitors partially restored the proliferation of CD4+ and CD8+ T cells, and downregulated the expression of COX2, prostaglandin E synthase, prostaglandin E2, and PD-L1 in CAFs. Conclusion: CAFs promote immune evasion by suppressing the function of CD4+ and CD8+ T cells via their effects on COX2 and PD-L1 in NSCLC. The immunosuppressive function of CAFs could be alleviated by COX2 inhibitors.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.76-81
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• 2017

Potentilla supina (Rosaceae) has traditionally been used to treat disorders of hemostasis, dysentery, malaria, bloody discharge and arthritis, and it has antinociceptive and anti-inflammatory properties. However, validity of the anti-inflammatory activity has not been scientifically investigated so far. Therefore, the aim of this study was to investigate the anti-inflammatory potential of P. supina using the ethanolic extract of P. supina and its sub-fractions. To evaluate the anti-inflammatory effects of P. supina, we examined the inflammatory mediators such as nitric oxide (NO), inducible nitric oxide synthase (iNOS) and prostaglandin $E_2$ ($PGE_2$) in RAW 264.7 cells. Our results indicated that ethyl acetate fraction significantly inhibited LPS-induced NO, iNOS and $PGE_2$ production in RAW 264.7 cells. This result showed that ethyl acetate fraction of P. supina is expected to be a good candidate for development into a source of anti-inflammatory agents.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.513-520
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• 1994

Background: The pathogenesis of silicosis has been focused on the interaction between alveolar macrophages and silica particle. Although fibrosis in silicosis has been studied extensively, the mechanism is still not fully understood. There is increasing evidence that monokines and arachidonic acid metabolites macrophage are involved in pathogenesis of silicosis. Recently, it was reported that prostaglandin E2 produced from macrophage counteracts the stimulatory effects of other monokines on fibroblast proliferation or collagen production. Until now, it was remained uncertain by which mechanism silica particle may activate alveolar macrophage to an enhanced release of prostaglandin E2. Methods: In order to investigate the relationship between the activity of alveolar macrophage and the production of $PGE_2$ from activated alveolar macrophage, the authors measured hydrogen peroxide and $PGE_2$ from alveolar macrophages activated by silica in vitro and from alveolar macrophages in the silicotic nodules from rat. Experimental silicosis was induced by intratracheal infusion of silica($SiO_2$) suspended in saline(50 mg/ml) in Sprague-Dawley rats. Results: produced by 1) The silicotic nodules with fibrosis were seen from the sections of rat lung at 60 days after intratracheal injection with 50 mg aqueous suspension of silica(Fig. 1). 2) In vitro, silica caused the dose dependent increase of hydrogen peroxide(p<0.05, Fig. 2A) and $PGE_2$(p>0.05, Fig. 2B) release from alveolar macrophages. Alveolar macrophages from rat with silicotic nodules released more hydrogen peroxide and $PGE_2$ than those of control group(p<0.05, Fig. 3). Conclusion: These results suggest that silica particle could activate macrophage directly and enhanced the release of $PGE_2$ and hydrogen peroxide from the alveolar macrophage.

• Journal of Life Science
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• v.23 no.11
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• pp.1397-1403
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• 2013

Fructus Sophorae, the dried ripe fruit of Styphnolobium japonicum (L.), is an herbal ingredient used in traditional Oriental medicine. This study was carried out to investigate the effects of Fructus Sophorae extracts (FSE) on immune modulation in a murine RAW 264.7 macrophage model. As immune response parameters, the production of prostaglandin $E_2$ ($PGE_2$) and tumor necrotic $factor-{\alpha}$ ($TNF-{\alpha}$) were evaluated. Our data revealed that FSE increased the macrophage activation and the production of $PGE_2$ and $TNF-{\alpha}$, which was consistently correlated with upregulation of cyclooxygenase-2 (COX-2) and $TNF-{\alpha}$ expression at both transcriptional and translational levels. On comparative cytokine protein array, FSE significantly increased several cytokines, which was associated with phosphorylation of mitogen- activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun N-terminal kinase (JNK), and Akt in RAW 264.7 cells. However, each inhibitor of these molecules attenuated the FSE-induced $PGE_2$ production. These results indicate that FSE activated macrophages through the activation of MAPKs and phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways in RAW 264.7 macrophages. These findings suggest that FSE may provide a promising source of an immunoenhancing agent.

• Tuberculosis and Respiratory Diseases
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• v.56 no.2
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• pp.169-177
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• 2004

Background : Cyclooxygenase is the main target enzyme for the nonsteroidal anti inflammatory drugs (NSAIDs) that have been shown to suppress carcinogenesis in both experimental models and epidemiological studies. COX-2 plays an important role in solid tumor growth, invasiveness and angiogenesis, through, in part, the synthesis of prostaglandins, such as prostaglandin E2 (PGE2). In this study, the prognostic significance of an increase in COX-2 expression in lung cancer samples was evaluated. Material and Methods : The expression of COX-2, by immunohistochemistry, was studied in paraffin-embedded tumor blocks obtained from 84 patients(male 67, female 17, with a mean age of 63, ranging from 34 to 84 years) who had undergone surgery at Wonkwang University Hospital, between 1997 and 2002. For the evaluation of the relationships between COX-2 expression, and the clinical stage, metastasis to lymph nodes and survival, those cases showing the respective antigen expression in >10% of the tumor cells were considered positive. Result : Of the 84 patients, 61 (73%) exhibited more than 10% COX-2 immunoreactivities in the tumor and normal cells, whereas the remaining 23 showed no increase in the expression of COX-2. There was no significant relationship between the increased expression of COX-2 and the disease stage(p=0.1002) or cell type(p=0.152). The median survival was longer for the patients with a negative, compared to positive, COX-2 expression(36 compared to 24 months, p<0.05). The two year-survival rate was also higher in the patients with a negative COX-2 expression (78%) than those with a positive expression (47%, Kaplan-Meier, Log Rank, p < 0.05). Conclusion : The median survival was longer in the patients with a negative, compared to positive, COX-2 expression was longer than those with positive COX-2, having undergone complete resection due to primary non-small cell lung cancer.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.349-356
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• 2012

Eicosanoid mediates various cellular immune responses in insects. This study aimed to discover its novel action on the modulation of hemocyte populations in response to an immune challenge. Upon bacterial challenge, the last instar larvae of the beet armyworm, Spodoptera exigua, increased their total hemocyte density in 2 h, and then decreased it to a basal hemocyte density level. This rapid increase in total hemocyte density was explained by an increase of plasmatocyte and spherulocyte densities. When larvae were treated with dexamethasone (a specific phospholipase $A_2$ ($PLA_2$) inhibitor), they did not show any increase in hemocyte density in response to bacterial challenge. However, the addition of arachidonic acid (a catalytic product of $PLA_2$) to larvae treated with dexamethasone recovered the up-regulation of hemocyte density in response to bacterial infection. Among eicosanoid, cyclooxygenase (COX), but not lipoxygenase (LOX), products seemed to mediate the increase of hemocyte density in response to bacterial infection because naproxene (a COX inhibitor) inhibited the hemocyte density increase, though esculetin (a LOX inhibitor) did not. Prostaglandin $E_2$, a COX product, significantly increased the hemocyte density even without bacterial infection. These results suggest that eicosaniod mediates a rapid increase in total hemocyte density in response to immune challenge.

• Kidney Research and Clinical Practice
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• v.36 no.2
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• pp.145-157
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• 2017

Background: Vitamin D is considered to exert a protective effect on various renal diseases but its underlying molecular mechanism remains poorly understood. This study aimed to determine whether paricalcitol attenuates inflammation and apoptosis during lipopolysaccharide (LPS)-induced renal proximal tubular cell injury through the prostaglandin $E_2$ ($PGE_2$) receptor EP4. Methods: Human renal tubular epithelial (HK-2) cells were pretreated with paricalcitol (2 ng/mL) for 1 hour and exposed to LPS ($1{\mu}g/mL$). The effects of paricalcitol pretreatment in relation to an EP4 blockade using AH-23848 or EP4 small interfering RNA (siRNA) were investigated. Results: The expression of cyclooxygenase-2, $PGE_2$, and EP4 were significantly increased in LPS-exposed HK-2 cells treated with paricalcitol compared with cells exposed to LPS only. Paricalcitol prevented cell death induced by LPS exposure, and the cotreatment of AH-23848 or EP4 siRNA offset these cell-protective effects. The phosphorylation and nuclear translocation of p65 nuclear factor-kappaB ($NF-{\kappa}B$) were decreased and the phosphorylation of Akt was increased in LPS-exposed cells with paricalcitol treatment. AH-23848 or EP4 siRNA inhibited the suppressive effects of paricalcitol on p65 $NF-{\kappa}B$ nuclear translocation and the activation of Akt. The production of proinflammatory cytokines and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cells were attenuated by paricalcitol in LPS exposed HK-2 cells. The cotreatment with an EP4 antagonist abolished these anti-inflammatory and antiapoptotic effects. Conclusion: EP4 plays a pivotal role in anti-inflammatory and antiapoptotic effects through Akt and $NF-{\kappa}B$ signaling after paricalcitol pretreatment in LPS-induced renal proximal tubule cell injury.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.747-758
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• 2002

The skin displays a highly active metabolism of polyunsaturated fatty acids (PUFA). Dietary deficiency of linoleic acid (LA), an 18-carbon (n-6) PUFA, results in characteristic scaly skin disorder and excessive epidermal water loss. Although arachidonic acid (AA), a 20-carbon (n6) PUFA, is metabolized via cyclooxygenase pathway into predominantly prostaglandin $E_2(PGE_2)$ and $PGF_{2{\alpha}}$, the metabolism of AA via the 15-lipoxygenase (15-LOX) pathway, which is very active in skin epidermis and catalyzes the transformation of M into predominantly 15S-hydroxyeicosatetraenoic acid (15S-HETE). Additionally, the 15-LOX also metabolizes the 18-carbon LA into 13S-hydroxyoctadecadienoic acid (13S-HODE), respectively. Interestingly, 15-LOX catalyzes the transformation of $dihomo-{\gamma}-linolenic$ acid (DGLA), derived from dietary gamma-linolenic acid, to 15S-hydroxyeicosatrienoic acid (15S-HETrE). These monohydroxy fatty acids are incorporated into the membrane inositol phospholipids which undergo hydrolytic cleavage to yield substituted-diacylglycerols such as 13S-HODE-DAG from 13S-HODE and 15S-HETrE-DAG from 15S-HETrE. These substituted-monohydroxy fatty acids seemingly exert anti-inflammatory/antiproliferative effects via the modulation of selective protein kinase C as well as on the upstream/down-stream nuclear MAP-kinase/AP-1/apoptotic signaling events.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1491-1497
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• 2007

Arginine deiminase (ADI, E.C. 3.5.3.6), one of the arginine deprivation enzymes, exhibits anticarcinogenic activities. The present study investigated the anti-inflammatory activities of the purified recombinant ADI originating from Lactococcus lactis ssp. lactis ATCC7962 (LADI). LADI dose-dependently inhibited lipopolysaccharide (LPS)-induced upregulation of inducible nitric oxide synthase and the production of nitric oxide in RAW 264.7 murine macrophages. The induction of cyclooxygenase-2 expression and subsequent production of prostaglandin $E_2$ by LPS was also attenuated by LADI treatment. Moreover, LADI inhibited the production of interleukin-6 in LPS-stimulated RAW 264.7 macrophages. These results indicate that LADI exerts anti-inflammatory effects, which may in part explain its chemopreventive potential.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.27-32
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• 2007

This study was conducted to examine the effects of prostaglandin $F_2{\alpha}(PGF_2{\alpha})$ and prostaglandin $E_2 (PGE_2)$ on the expansion and hatching of bovine embryos. During the in vitro culture, embryos were cultured with the following groups: (1) 0, 1, 10 and 100ng/ml $PGF_2{\alpha}$ (2) 0, 1, 10 and 100 ng/ml $PGF_2{\alpha}$, (3) low concentration of $PGF_2{\alpha}$ ; low concentration of $PGF_2{\alpha}$, (1ng/ml : 1ng/ml), (4) low concentration of $PGF_2{\alpha}$ : high concentration of $PGF_2{\alpha}$ (1ng/ml : 10ng/ml) (5) high concentration of $PGF_2{\alpha}$ : low concentration of $PGE_2$ (10ng/ml 1ng/ml) (6) high concentration of $PGF_2{\alpha}$ : high concentration of $PGE_2$(10 ng/ml : 10ng/ml). In the results of this study, treatment of $PGF_2{\alpha}$ or $PGE_2$ did not affect in vitro development to blastocysts. However, the hatching rates of embryos cultured with 10ng/ml $PGE_2$(10.3%) and 1ng/ml $PGF_2{\alpha}$ 10ng/ml $PGE_2$(22.2%) were significantly (P<0.05) higher than in control (4.3% and 12.7%) and other treatment groups. All groups treated with high concentrations of $PGF_2{\alpha}$ showed decreased hatching rates. Thus, this results suggested that $PGF_2{\alpha}\;and\;PGE_2$ were concerned with the hatching in bovine embryos, and their effects on hatching were different by the concentrations.