• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.101-101
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• 2003

Prostaglandins (PGs) and nitric oxide (NO) produced by inducible cyclooygenase (COX-2) and nitric oxide synthase (iNOS), respectively, have been implicated as important mediators in the process of inflammation and carcinogenesis. On this line, the potential COX-2 or iNOS inhibitors have been considered as anti-inflammatory and cancer chemopreventive agents. In our continuing efforts of searching for novel cancer chemopreventive agents from natural products, we isolated natural sesquiterpenoids as potential COX-2 and iNOS inhibitors in cultured lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. Alantolactone, a natural eudesmane-type sesquiterpenoid, exhibited a potent inhibition of COX-2 (IC50 = 0.4 $\mu\textrm{g}$/$m\ell$) and iNOS activity (IC50 = 0.08 $\mu\textrm{g}$/$m\ell$) in the assay system determined by PGE2 and NO accumulation, respectively. The inhibitory potential of alantolactone on the PGE2 and NO production was well coincided with the suppression of COX-2 and iNOS protein and mRNA expression in LPS-induced macrophages. Furthermore, alantolactone inhibited NF-kB but not AP-l binding activity on nuclear extracts evoked by LPS-stimulated macrophage cells, suggesting the possible involvement of NF-kB in the regulation of COX-2 and iNOS expression. In further study with COX-2-expressing human colon HT-29 cells, alantolactone inhibited the cell proliferation, down-regulated COX-2, and inhibited the ERK phosphorylation in the early time. These results suggest that a natural sesquiterpenoid alantolactone might be a potential lead candidate for further developing COX-2 or iNOS inhibitor possessing cancer chemopreventive or anti-inflammatory activity

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5903-5908
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• 2012

Objective: The purpose of this study is to investigate the combined effects of exemestane and aspirin on MCF-7 human breast cancer cells. Methods: Antiproliferative effects of exemestane and aspirin, alone and in combination, on growth of MCF-7 human breast cancer cells were assessed using the MTT assay. Synergistic interaction between the two drugs was evaluated in vitro using the combination index (CI) method. The cell cycle distribution was analyzed by flow cytometry and Western blotting was used to investigate the expression of cyclooxygenase-1, cyclooxygenase-2 and Bcl-2. Results: MTT assays indicated that combination treatment obviously decreased the viability of MCF-7 human breast cancer cells compared to individual drug treatment (CI<1). In addition, the combination of exemestane and aspirin exhibited a synergistic inhibition of cell proliferation, significantly arrested the cell cycle in the $G_0/G_1$ phase and produced a stronger inhibitory effect on COX-1 and Bcl-2 expression than control or individual drug treatment. Conclusion: These results indicate that the combination of exemestane and aspirin might become a useful method to the treatment of hormone-dependent breast cancer. The combination of the two inhibitors significantly increased the response as compared to single agent treatment, suggesting that combination treatment could become a highly effective approach for breast cancer.

• Journal of Acupuncture Research
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• v.40 no.4
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• pp.368-376
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• 2023

Background: Although bee venom (BV) has clinical benefits in osteoarthritis and rheumatoid arthritis, it has not been tested as treatment for gouty arthritis. Moreover, in vitro, BV has been proven to exhibit anti-inflammatory and positive effects on osteoarthritis, but only limited evidence can confirm its beneficial effects on gout. Thus, this study aims to assess the anti-inflammatory effects of BV on monosodium urate (MSU)-induced THP-1 monocytes. Methods: THP-1 monocytes were differentiated into mature macrophages using phorbol 12-myristate 13-acetate (PMA) and pretreated for 6 hours with BV and a Caspase-1 inhibitor in a physiologically achievable range of concentrations (BV, 0.1-1 ㎍/mL; Caspase-1 inhibitor, 1-10 μM), followed by MSU crystal stimulation for 24 hours. The secretions of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), IL-6, IL-8, cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), and nitric oxide (NO) were increased in the MSU crystal-stimulated THP-1 cells. Results: Caspase-1 inhibitors suppressed the production of all mediators in a dose-dependent manner. BV worked on equal terms with Caspase-1 inhibitors and showed more satisfactory effects on TNF-α, PGE2, COX-2, and inducible nitric oxide synthase (iNOS). Moreover, the western blot analysis revealed that BV regulated the transcriptional levels of these mediators via the suppression of extracellular signal-regulated kinase (ERK) pathway activation. Conclusion: The results of the present study clearly suggest that BV inhibits MSU-induced inflammation in vitro, suggesting a possible role for BV in gout treatment.

• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.243-259
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• 1993

The bone resorbing activity of $PGE_2$ and elevated level of prostaglandins(PGs) and thromboxanes (TXs) in inflamed gingiva which are cyclooxygenase(C) metabolites have been well documented. Nonsteroidal anti-inflammatory drugs(NSAIDs) have been known to suppress gingival inflammation and bone resorption through the specific inhibitory action on the C pathway thereby decrease of various C metabolites. Recent studies provide unequivocal results that gingival tissue metabolizes arachidonic acid(AA) mainly through lipoxygenase(L) pathway. And the results of our previous experiments suggest that indomethacin may have inhibitory action on L as well as C. Thus we started this study to show the influences of several C inhibitors on the L activity at therapeutic and toxic dosage. Periodontal tissue samples were obtained from patients with advanced periodontitis and incubated with $^{14}C-AA(0.2{\mu}Ci)$ and various enzyme inhibitors. The tissue lipid extracts were separated by means of thin layer chromatography(TLC) and analyzed by means of autoradiography and TLC analyzer. Our results showed that aspirin inhibited C more selectively than L, however at higher concentration it also decreased HETEs production significantly. Indomethacin showed dose-dependent inhibition of L as well as C and all of the L metabolites were decreased to the same degree by high concentration of indomethacin. AA-861, which is an experimental tool of selective L inhibitor, showed inhibition of HETEs production but no effect on the production of $TXB_2$, PGs and $LTB_4$. Various propionic acid derivatives NSAIDs(ibuprofen, flurbiprofen, naproxen) showed the same patterns of effect on AA metabolism each other that was profound inhibition of PGs production, to the less degree HETEs and $TXB_2$ production, and of no effect on the $LTB_4$ production.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.145-152
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• 1990

We recently reported a development of an experimental system which can identify the release of a superoxide-dependent vasorelaxant factor from endothelial cells using a two-bath system. In the present work, we further exploited the above system and observed whether the superoxide-dependent relaxing factor(s), released from the porcine coronary artery (PCA) endothelium, was similar in relaxation to those obtained from cat thoracic aortic endothelium and cultured endothelial cells of bovine aorta. However, there was observed a novel difference among the former one and the latter two relaxing factors; the release of relaxing factor from PCA endothelium can be inhibited either by catalase or by superoxide dismutase (SOD), whereas the latter two can be inhibited only by SOD. It was further attempted to characterize the synthetic mechanisms of the relaxing factors: (1) They were readily inhibited by various lipoxygenase inhibitors (gossypol, nordihydroguaiaretic acid, AA 861, and eicosatetraynoic acid). (2) They were not inhibited by cyclooxygenase inhibitor (indomethacin) and by cytochrome P-450 monooxygenease inhibitors (proadifen and cimetidine). Thus, it is likely that these relaxing factors, although obtained from different species, show common functional roles of arteriolar relaxation. It is suggested that they are related to pathophysiological involvement of various tissue ischemia-reperfusion injuries.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.373-382
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• 2003

Magnesium ion ($Mg^{2+}$) is a vasodilator, but little is known about its mechanism of action on vascular system. In vitro, extracellular magnesium sulfate ($MgSO_4$) produced relaxation in phenylephrine (PE) or high KCl-precontracted isolated rat thorocic aorta with (+E) or without (-E) endothelium in a concentration-dependent manner. The $MgSO_4$-induced relaxations were not affected by removal of the endothelium. Pretreatment of +E or -E aortic rings with nitric oxide synthase (NOS) inhibitors ($20{\mu}M$ L-NNA, $100{\mu}M$ L-NAME, $1{\mu}M$ dexamethasone and $400{\mu}M$ aminoguanidine), cyclooxygenase inhibitor ($10{\mu}M$ indomethacin), guanylate cyclase inhibitors ($10{\mu}M$ ODQ and $30{\mu}M$ methylene blue) and $Ca^{2+}$ transport blocker ($10{\mu}M$ ryanodine) did not affect the relaxant effects of $MgSO_4$. $Ca^{2+}$ channel blockers ($0.3{\mu}M$ nifedipine and $0.5{\mu}M$ veropamil) completely decreased the relaxant effects of $MgSO_4$ in +E and -E aortic rings. However, in $Ca^{2+}$-free medium, $MgSO_4$-induced vasorelaxation was potentiated and this response was inhibited by nifedipine. Protein kinase C (PKC) inhibitors ($1.0{\mu}M$ staurosporine, $0.5{\mu}M$ tamoxifen and $0.1{\mu}M$ H7) or PLC inhibitor ($100{\mu}M$ NCDC) markedly decreased the relaxant effects of $MgSO_4$ in +E and -E aortic rings. In vivo, infusion of $MgSO_4$ elicited significant decreases in arterial blood pressure. After intravenous injection of nifedipine ($150{\mu}g/kg$) and NCDC (3 mg/kg), infusion of $MgSO_4$ inhibited the $MgSO_4$-lowered blood pressure markedly. However, after introvenous injection of saponin (15 mg/kg), L-NNA (3 mg/kg), L-NAME (5 mg/kg), indomethacin (2 mg/kg), methylene blue (15 mg/kg) and aminoguanidine (10 mg/kg) failed to inhibit it. These results suggest that endothelial NQ-cGMP or prostaglandin pathway is not involved in vasorelaxant or hypotensive action of $Mg^{2+}$ and that these effects are due to the inhibitory action of $Mg^{2+}$ on the $Ca^{2+}$ channel or PLC-PKC pathway, and are due to the competitive influx of $Mg^{2+}$ and $Ca^{2+}$ through the $Ca^{2+}$ channel.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.116-124
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• 2001

Nitric oxide is a labile, gaseous, broad spectrum second messenger that used in various tissues and cells. If it is induced by endogenously and exogenously in the neuronal cells, it is able to mediate analgesia or hyperalgesia at the periphery and in the spinal level respectively. This dual role of nitric oxide in the sensory system is very intriguing but has not been fully understood yet. In this experiment, acetylcholine (300 $\mu$g/paw), sodium nitroprusside (600 $\mu$g/paw), and L-arginine (300 $\mu$g/paw) represented antinociceptive effect to noxious topical stimulus, but pronociceptive responses followed by spinally application (20$\mu$g/5$\mu$l, 10$\mu$g/3$\mu$l, 500$\mu$g/5$\mu$l respectively). Calcium ion is critical element which activates nitric oxide synthase, therefore verapamil (300 $\mu$g/paw) and NOS inhibitor (20 mg/kg, L-NAME or L-NOArg) are injected into right hind paw (i.pl.). When verapamil is combined with NOS inhibitors analgesic effects through NO-cGMP pathway are inhibited as compared with ACh alone. Diluted formalin (2.5%), when injected into rats'hind paw (0.05 ml), elicited a biphasic algesic responses and nitric oxide had an analgesic effect on both $A\delta$ and C sensory nerve fibers which manipulate the phases respective1y. Nitric oxides, which produced from constitutive nitric oxide synthase, activated cyclooxygenase-type I and then prostaglandins are produced from them. So, indomethacin and ibuprofen, inhibitors of COX$_1$enzyme, when pretreated intraperitoneally (100 mg/kg) could reduce the hyperalgesic state. From these results, it is possible to imagine that the intrathecally administered NO donors expressed hyperalgesia through both long-term potentiation mechanism and arachidonic acid-prostaglandin cascade.

• Journal of Dental Anesthesia and Pain Medicine
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• v.20 no.1
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• pp.19-27
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• 2020

Background: Surgical extraction of third molars is associated with postoperative pain and swelling at the extraction site. Pain is commonly managed using non-steroidal anti-inflammatory drugs (NSAIDs). Postoperative pain is usually moderate to severe in the first 12 h postoperatively and lasts for 3-5 days. However, with NSAIDs, these symptoms usually subside within 24 h. Diclofenac sodium and etodolac are NSAIDs, more selectively cyclooxygenase-2 inhibitors, with good analgesic efficacies. Methods: We compared the safety and analgesic efficacy of diclofenac sodium with etodolac peroral after surgical extraction of third molars in a double-blind, double-dummy, parallel-group study. The subjective pain improvement and pain relief after 2, 6, 24, 48, and 72 h using the visual analogue scale were measured as the study outcome. Results: Etodolac was equivalent to diclofenac sodium in pain alleviation at all postoperative time periods. No significant differences were found between diclofenac sodium and etodolac groups (P > 0.05). Both study medications were well tolerated and safe with mild adverse effects in only a few participants. Conclusion: Diclofenac sodium and etodolac are comparable in terms of analgesic efficacy and safety after surgical removal of third molars.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.4
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• pp.277-287
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• 2022

Background: Inflammatory dental diseases that occur during pregnancy can cause preterm labor and/or intrauterine growth restriction. Therefore, proactive treatment of dental diseases is necessary during pregnancy. Dexmedetomidine (DEX) is a widely used sedative in the dental field, but research on the effect of DEX on pregnancy is currently insufficient. In this study, we investigated the effects of co-treatment with DEX and lipopolysaccharide (LPS) on inflammatory responses in human amnion-derived WISH cells. Methods: Human amnion-derived WISH cells were treated with 0.001, 0.01, 0.1, and 1 ㎍/mL DEX with 1 ㎍/mL LPS for 24 h. Cytotoxicity of WISH cells was evaluated by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression of cyclooxygenase-2 (COX-2), prostaglandin E₂ (PGE₂), p38, and nuclear factor kappa B (NF-𝜅B) was examined by western blot analysis. The mRNA expression of pro-inflammatory cytokines such as interleukin (IL)-1𝛽 and tumor necrosis factor (TNF)-𝛼 was analyzed by real-time quantitative polymerase chain reaction. Results: Co-treatment with DEX and LPS showed no cytotoxicity in the WISH cells. The mRNA expression of IL-1𝛽 and TNF-𝛼 decreased after co-treatment with DEX and LPS. DEX and LPS co-treatment decreased the protein expression of COX-2, PGE₂, phospho-p38, and phospho-NF-𝛋B in WISH cells. Conclusion: Co-treatment with DEX and LPS suppressed the expression of COX-2 and PGE₂, as well as pro-inflammatory cytokines such as IL-1𝛽 and TNF-𝛼 in WISH cells. In addition, the anti-inflammatory effect of DEX and LPS co-treatment was mediated by the inhibition of p38/NF-𝜅B activation.

• IMMUNE NETWORK
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• v.6 no.4
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• pp.204-210
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• 2006

Background: Nitric oxide (NO) in articular chondrocytes regulates dedifferentiation and inflammatory responses by modulating MAP kinases. In this study, we investigated whether the Src kinase in chondrocytes regulates NO-induced dedifferentiation and cyclooxygenase-2 (COX-2) expression. Methods: Primary chondrocytes were treated with various concentrations of SNP for 24 h. The COX-2 and type II collagen expression levels were determined by immunoblot analysis, and prostaglandin $E_2\;(PGE_2)$ was determined by using a $PGE_2$ assay kit. Expression and distribution of p-Caveolin and COX-2 in rabbit articular chondrocytes and cartilage explants were determined by immunohistochemical staining and immunocytochemical staining, respectively. Results: SNP treatment stimulated Src kinase activation in a dose-dependent manner in articular chondrocytes. The Src kinase inhibitors PP2 [4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo(3,4-d)pyrimidine], a significantly blocked SNP-induced p38 kinase and caveolin-1 activation in a dose-dependent manner. Therefore, to determine whether Src kinase activation is associated with dedifferentiation and/or COX-2 expression and $PGE_2$ production. As expected, PP2 potentiated SNP-stimulated dedifferentiation, but completely blocked both COX-2 expression and $PGE_2$ production. And also, levels of p-Caveolin and COX-2 protein expression were increased in SNP-treated primary chondrocytes and osteoarthritic and rheumatoid arthritic cartilage, suggesting that p-Caveolin may playa role in the inflammatory responses of arthritic cartilage. Conclusion: Our previously studies indicated that NO caused dedifferentiation and COX-2 expression is regulated by p38 kinase through caveolin-1 (1). Therefore, our results collectively suggest that Src kinase regulates NO-induced dedifferentiation and COX-2 expression in chondrocytes via p38 kinase in association with caveolin-1.