• The Korean Journal of Zoology
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• v.39 no.3
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• pp.266-272
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• 1996

Experiments were carried out to ascertain whether gonadotropin or a phorbol ester (12-O-tetradecanoyl phorbol-13-acetate, TPA) induces oocyte ovulation and stimulates prostaglandin synthesis by Rana ovarian follicles in vitro. Rana nigromaculata collected from underground in spring were utilized for the present experiment. Treatment of frog pituitary homogenate (FPH) or TPA to ovarian fragments in culture induced oocyte ovulation in a dose dependent manner and stimulated prostaglandin F2a (PGF$_2$$\alpha$ synthesis. Both treatruents were more effective in inducing the ovulation and PGF$_2$$\alpha$ secretion by the follicles obtained in May than those in April. A Protein kinase C inactivator, 1-(5-isoquinolinyl-sulfonyl)-2-methyl-piperazine (H-7), or cyclooxygenase inhibitor, indomethacin (IM) suppressed the FPH- or TPA-induced PGF$_2$$\alpha$ production, but IM failed to suppress the FPH- or TPA-induced ovulation. Time course of oocyte ovulation and PGF$_2$$\alpha$ secretion by FPH and TPA treatments were very similar to each other. FPH stimulated progesterone secretion by the follicle but TPA failed to do so. Taken together, the data presented here suggest that protein kinase C (PKC) in follicle play a role in the ovulation process of Rana nigromaculata, probably via prostaglandin synthesis.

• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.345-356
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• 2004

The triclosan was shown to have anti-microbial and anti-inflammatory effect with inhibition of inflammatory mediators such as prostaglandin $E_2(PGE_2)$. The purpose of this study was to elucidate whether and how $PGE_2$ could be inhibited by triclosan in human gingival fibroblast. Human gingival fibroblast-1 cells (ATCC CRL2014) were pre-treated for 1 hour with triclosan (0.001 ${\mu}/ml{\sim}10$ ${\mu}/ml$) and then stimulated with $TNF-{\alpha}$ (1.0 ng/ml). $PGE_2$ synthesis was evaluated by ELISA and gene expression of COX-1 and COX-2 was evaluated by RT-PCR after $TNF-{\alpha}$, triclosan, and NS-398 (COX-2 inhibitor, 5, ${\mu}M$) and/ or cycloheximide (protein synthesis inhibitor, 2 ${\mu}g/ml$). Triclosan was cytotoxic to human gingival fibroblasts in the concentration higher than 1.0 ${\mu}g/ml$ for longer than 24 hours in tissue culture. The $PGE_2$ synthesis was inhibited by triclosan in dose-dependent manner. Greater COX-2 mRNA suppression was observed with triclosan (0.1 ${\mu}g/ml$) than with $TNF-{\alpha}$ alone, without change in COX-1 gene expression. Inhibitory effects of triclosan on $PGE_2$ synthesis disappeared in presence of cycloheximide. This study suggests that triclosan inhibit prostaglandin $E_2$ at the level of COX-2 gene regulation and require de novo protein synthesis.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.386-396
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• 1995

Interieukin 1${\beta}$ is a potent bone resorptive cytokine which mediates soft tissue destruction through the stimulatidn of prostaglandin production and the induction of collagenase. This constellation of activities suggests a role of IL-1${\beta}$ in the pathogenesis of periodontal disease. The purpose of this study was to evaluate the effects of herbal extracts on production and activity of IL-1${\beta}$. When LPS was added to cultured human blood monocytes, the effects of herbal extracts on the production of IL-1${\beta}$ was evaluate by thymocyte stimulation assay. When rHuIL-1${\beta}$ was added to cultured human gingival fibroblasts, the effects of herbal extracts on production of $PGE_2$ was evaluated by ELISA and when it was added to cultured mouse calvaria, the effects on bone resorption was estimated by .$^{45}Ca$-release bone resorption assay. The herbal extracts that had been used in this study were as follows; Asparagi Radix, Schzandrae Fractus, Zizyphi Fractus and Rhois Galla. The following results were obtained from this study. 1. All these extracts effectively inhibited the production of IL-1${\beta}$ on cultured human blood monocytes. 2. All these extracts effectively inibited the production of $PGE_2$ on cultured human gingival fibroblasts. 3. All these extracts did not effectively inhibit the bone resorption induced by rHulL-1${\beta}$ on cultured mouse calvaria.

• Journal of Veterinary Clinics
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• v.34 no.3
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• pp.172-177
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• 2017

Fucoidan, a cell wall polysaccharide found in the brown seaweed, is reported to have broad-spectrum biological activities. The objectives of this study were to examine the effect of fucoidan on prostaglandin $E_2$ ($PGE_2$) and cyclooxygenase-2 (COX-2) expression in lipopolysaccharide (LPS)-stimulated porcine peripheral blood mononuclear cells (PBMCs) and to determine whether these effects are involved in Akt activation. The levels of $PGE_2$ production in the culture supernatants from PBMCs were determined by the enzyme-linked immunosorbent assay (ELISA) kit and the levels of COX-2 mRNA were measured by real time polymerase chain reaction (RT-PCR). Akt activity was determined by Western blot analysis. Fucoidan in LPS-$na{\ddot{i}ve}$ PBMCs has no effect on $PGE_2$ production and COX-2 mRNA expression. Furthermore, fucoidan does not affect Akt activation in LPS- $na{\ddot{i}ve}$ PBMCs. However, $PGE_2$ production and COX-2 mRNA expression on PBMCs were remarkably enhanced by LPS stimulation. Akt activity was also increased by LPS. Increasing effects of $PGE_2$ production and COX-2 mRNA expression in PBMCs induced by LPS were suppressed by addition of fucoidan. In addition, fucoidan reduced an increase in Akt activity in LPS-stimulated PBMCs. These results suggested that fucoidan exerts potent anti-inflammatory properties by suppression of $PGE_2$ production, COX-2 mRNA expression and Akt activation in LPS-stimulated PBMCs.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.202-210
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• 1989

The effects of Ginseng saponins on the in vitro biosynthesis of prostaglandins were examined in order to identify the role of some Ginseng components on the regulation of arachidonic arid metabolism. The productions of prostaglandin $E_2$ (PG$E_2$), $F_2$ (PGF2), thromboxane $B_2$(TX$B_2$) and 6-ketoprostaglandin Fl (6-Keto-PGF1) from [3Hl-arachidonic acid were evaluatpf by radiochromatographic analysis with rabbit kidney microtome, human platelet homogenate and bovine aortic microsome. The amounts of the total prostaglandins produced by cyclooxygenase activity and malondialdehyde from arachidonic acid didn't show significant changes in the presence of Ginseng saponins. Both of panaxadiol and panaxatriol didn't affect the production of PG$E_2$ while the formations of PG$F_2$( and TX$B_2$( were nearkedly reduced and the production of prostacyclin was increased. The formation of TXBE was reduced by ginsenoside $Rb_2$, Rc, and Re, however the production of 6-Keto-PGF1 was increased dose dependently up to 1 mg/ml. Moreover, platelet aggregations induced by arachidonic acid and U46619 (9.11-methanepoxy PG$H_2$), TX$A_2$ mimetics, were also inhibited by three ginsenosides. The effect of G-Re on prostacyclin synthetase was inhibited by tranylcypromine, prostacyclin synthetase inhibitor. These results suggest that Ginseng saponins may not directly act on cyclooxygenase but affect on the divergent pathway from endoperoxide.

• Korean Journal of Acupuncture
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• v.21 no.2
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• pp.125-137
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• 2004

Objectives : Recently, Herbal-acupuncture therapeutics has been used for the treatment of inflammatory diseases such as rheumatoid arthritis. Especially, we have been interested in chemical mediators concerned with inflammation such as prostaglandin, cytokine, nitrous oxide. The purpose of this study is investigated that the effect of Chelidonii Herbal-acupuncture solution in lipopolysaccharide-stimulated RAW 264.7 macrophages, performed several expeimental items : those are prostaglandin $E_2$, nitric oxide and cyclooxygenase-2. Methods : The cytotoxicity of Chelidonii Herbal-acupuncture solution in RAW 264.7 macrophages were measured by MTT-based cytotoxicity assay. In order to observe cyclooxygenase-2 mRNA expression in lipopolysaccharide-stimulated RAW 264.7 macrophages, RT-PCR was used. Prostaglandin $E_2$ formation and nitric oxide production was measured by competitive enzyme immunoassay and Griess assay. Results : 1.The MTT assay demonstrated that cytotoxic effect of Chelidonii Herbal-acupuncture solution in RAW 264.7 macrophages were not appeared before concentration of 1mg/ml. 2.Chelidonii Herbal-acupuncture solution inhibited cyclooxygenase-2 mRNA expression in lipopolysaccharide-stimulated RAW 264.7 macrophages. 3. Chelidonii Herbal-acupuncture solution inhibited nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages. 4. Chelidonii Herbal-acupuncture solution inhibited prostaglandin $E_2$ formation in lipopolysaccharide-stimulated RAW 264.7 macrophages. Conclusions : On the basis of these results, It was shown that Chelidonii Herbal-acupuncture solution is significantly able to inhibit the production of $PGE_2$ and NO, as well as COX-2 mRNA expression. Our results may provide new mechanism by which Chelidonii Herbal-acupuncture solution accounts for its beneficial effect on accelerating wound healing and anti-inflammation.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.4
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• pp.343-346
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• 1990

A study was conducted to determine the effect of prostaglandin $F_2$ alpha ($PGF_2$ alpha) on the reaction time and seminal characteristics of buffalo bulls. Semen was collected from three Murrah bulls in three periods: pre-treatment, treatment and post-treatment. During the treatment period each bull was administered 2 ml $PGF_2$ alpha (Synchrocept, Fenprostalene) im, 1 hour prior to semen collection. In the post-treatment, semen was collected 7 days after the last injection of $PGF_2$. Semen samples were evaluated immediately after collection. Pre-collection injection of $PGF_2$ alpha has no significant effect on reaction time, semen volume, percentage motility, sperm concentration and total number of sperms per ejaculate. Fluctuations in semen color and consistency were observed. There is a significant (p<0.05) increase in the mean percentage of normal spermatozoa during the treatment and post treatment periods. Likewise, administration of PG results into a significant (p<0.05) rise on the average percentage of live sperms but this effect was not manifested in the post-treatment period. Improvement in mass activity was observed during the treatment and post-treatment periods.

• International Journal of Oral Biology
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• v.42 no.4
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• pp.149-153
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• 2017

Cyclooxygenase-2 (COX-2)-mediated prostaglandin $E_2$ ($PGE_2$) plays a key role in development and progression of inflammatory responses and Porphyromonas gingivalis is a common endodontic pathogen. In this study, we investigated induction of COX-2 and $PGE_2$ by P. gingivalis in human dental pulp cells (HDPCs). P. gingivalis increased expression of COX-2, but not that of COX-1. Increased levels of $PGE_2$ were released from P. gingivalis-infected HDPCs and this $PGE_2$ increase was blocked by celecoxib, a selective COX-2 inhibitor. P. gingivalis activated all three types of mitogen-activated protein kinases (MAPKs). P. gingivalis-induced activation of nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) was demonstrated by the results of phosphorylation of $NF-{\kappa}B$ p65 and degradation of inhibitor of ${\kappa}B-{\alpha}$ ($I{\kappa}B-{\alpha}$). Pharmacological inhibition of each of the three types of MAPKs and $NF-{\kappa}B$ substantially attenuated P. gingivalis-induced $PGE_2$ production. These results suggest that P. gingivalis should promote endodontic inflammation by stimulating dental pulp cells to produce $PGE_2$.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1675-1681
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• 2019

Clostridium difficile toxin A is known to cause colonic epithelial cell apoptosis, which is considered the main causative event that triggers inflammatory responses in the colon, reflecting the concept that the essential role of epithelial cells in the colon is to form a physical barrier in the gut. We previously showed that toxin A-induced colonocyte apoptosis and subsequent inflammation were dependent on prostaglandin E2 ($PGE_2$) produced in response to toxin A stimulation. However, the molecular mechanism by which $PGE_2$ mediates cell apoptosis in toxin A-exposed colonocytes has remained unclear. Here, we sought to identify the signaling pathway involved in toxin A-induced, $PGE_2$-mediated colonocyte apoptosis. In non-transformed NCM460 human colonocytes, toxin A exposure strongly upregulated expression of Bak, which is known to form mitochondrial outer membrane pores, resulting in apoptosis. RT-PCR analyses revealed that this increase in Bak expression was attributable to toxin A-induced transcriptional upregulation. We also found that toxin A upregulation of Bak expression was dependent on $PGE_2$ production, and further showed that this effect was recapitulated by an Prostaglandin E2(PGE2) receptor-1 receptor agonist, but not by agonists of other EP receptors. Collectively, these results suggest that toxin A-induced cell apoptosis involves $PGE_2$-upregulation of Bak through the EP1 receptor.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.77-84
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• 1998

Ureteral obstruction causes increase in renal blood flow (RBF) and partial impairment of the autoregulation of RBF. Although increased renal prostaglandin production is responsible for the former, it is not clear whether or not it is also responsible for the latter. Therefore, we investigated the role which prostaglandins play in the autoregulation of RBF during an ureteral pressure elevation (40 $cmH_2O$). Since the major mechanism of RBF autoregulation is the tubuloglomerular feedback, studying the interaction between ureteral pressure and RBF autoregulation may reveal the role of prostaglandin in tubuloglomerular feedback. To pursue the purpose, six anesthetized dogs were prepared for the measurements of RBF, mean sytemic and renal arterial pressure (RAP) and the manipulation of ureteral pressure. The autoregulation curves were determined during both control and elevation of the ureteral pressure, before and after the pretreatment with indomethacin, a cyclooxygenase inhibitor. The desired ureteral pressure was achieved by vertically elevating the water-filled reservoir connected to the ureteral catheter to 40 cm above the kidney level. In response to the elevation of the ureteral pressure, RBF increased from $170{\pm}8 ml{\cdot}min^{-1}\;to\;189{\pm}8$, and the systemic arterial pressure didn't change significantly. During spontaneous urine flow, RBF autoregulation was abolished when RAP was reduced to $59{\pm}3$ mmHg. On the other hand, during the ureteral pressure elevation, the autoregulation curves shifted upward and rightward from control, and the pressure when RBF autoregulation was abolished was $74{\pm}3$ mmHg. The pretreatment of the dogs with indomethacin failed to affect the lower limit of RBF autoregulaion during both control ($63{\pm}5$ mmHg) and the elevated ureteral pressure ($77{\pm}5$ mmHg). Since RBF failed to increase in response to the elevated ureteral pressure, RBF autoregulation curves obtained during the elevated ureteral pressure shifted only rightward from indomethacin control. The results indicate that the increased intrarenal level of prostaglandin or prostaglandin-induced vasodilation does not appear to bear any relation to the reduction in the autoregulatory capacity during partial ureteral obstruction. It seems that the partial impairment of the autoregulation during acute ureteral obstruction is due to the consumption of tubuloglomerular feedback mechanism at spontaneous RAP and that prostaglandin is neither mediator nor effector of tubuloglomerular feedback mechanism.