• Title/Summary/Keyword: COX-2

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Rhus Verniciflua Stokes Extract Suppresses Expression of Metalloproteinases, iNOS and COX-2 in THP-1 Cells Via Inhibiting NF-𝜅B and MAPK Phosphorylation

  • Ko, Hwanjoo;Jang, Eungyeong;Kim, Youngchul
    • The Journal of Korean Medicine
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    • v.41 no.4
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    • pp.12-26
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    • 2020
  • Objectives: The aim of this study is to investigate the mechanisms involved in the anti-inflammatory and anti-tumor effects of Rhus verniciflua Stokes (RVS) on PMA-differentiated human monocytic leukemia THP-1 cells. Methods: Cells were treated with various concentrations of RVS decoction (0-300㎍/ml) for 24, 48, and 72h. Cell viability was evaluated by MTS/PMS assay. The expressions of MMP-2, MMP-9, TIMP-1, TIMP-2, iNOS and COX-2 mRNA and proteins were measured using RT-PCR and western blotting, respectively. Results: RVS suppressed expression of MMP-2 and MMP-9 mRNA. It also down-regulated iNOS and COX-2 mRNA and protein expression. RVS inhibited NF-𝜅B p65 activity and the phosphorylation of Akt and MAPK (ERK and p38 MAPK). Instead, the phosphorylation of JNK is increased at a very low concentration but decreased at higher concentrations. Conclusion: RVS is regarded to inhibit the expression of MMP and TIMP as well as iNOS and COX-2 gene expression via directly inhibiting the activation of NF-𝜅B and phosphorylation of MAPK pathway in THP-1 cells. This suggests RVS have potential to be used as a therapeutic agent for acute myeloid leukemia (AML).

Inhibitory effects of resveratrol analogs on lipopolysaccharide-induced cyclooxygenase-2 activity in RAW264.7 cells

  • Park, Eun-Jung;Min, Hye-Young;Park, Jae-Eun;Kim, Sang-Hee;Lee, Sang-Kook
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.245.1-245.1
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    • 2002
  • It has been known that resveratrol, a phytoalexin present in grapes mainly, has antioxidant. anti-inflammatory, and cancer chemopreventive activity. One mechanism of its anti-inflammation and cancer prevention is considered to modulate cyclooxygense-2 (COX-2) activity. Since COX-2 plays an important role in inflammation and carcinogenesis, the potential COX-2 inhibitors have been considered as anti-inflammatory or cancer chemopreventive agents. (omitted)

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Protection of Primary Cultured Mouse Hepatocytes from Chemical Hypoxia-induced Injury by Hydrogen Sulfide (화학적 허혈에 의해 손상된 마우스 간세포에 대한 hydrogen sulfide의 간세포 보호 효과)

  • Lee, Min Young
    • Journal of Life Science
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    • v.23 no.11
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    • pp.1342-1350
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    • 2013
  • We examined the effect of hydrogen sulfide ($H_2S$) in chemical hypoxia-induced injury in mouse hepatocytes. Cell viability was significantly decreased by cobalt chloride ($CoCl_2$), a well-known hypoxia mimetic agent in a time- and dose- dependent manner. Sodium hydrosulfide (NaHS, a donor of $H_2S$) pretreatment before exposure to $CoCl_2$ significantly attenuated the $CoCl_2$-induced decrease of cell viability. $CoCl_2$ treatment resulted in an increase of intracellular ROS generation, which is inhibited by NaHS or N-acetyl-cysteine (NAC, a ROS scavenger), and p38 MAPK phosphorylation, which is also blocked by NaHS or NAC. The $CoCl_2$-induced increase of the Bax/Bcl-2 ratio was attenuated by NaHS, NAC, and SB 203580 (p38 MAPK inhibitor). The $CoCl_2$-induced decrease of cell viability was also attenuated by NaHS, NAC, and SB 203580 pretreatment. Additionally, NaHS inhibited the $CoCl_2$-induced COX-2. Similar to the effect of NaHS, NAC blocked $CoCl_2$-induced COX-2 expression. Furthermore, NS-398 (a selective COX-2 inhibitor) attenuated not only the $CoCl_2$-induced increase of the Bax/Bcl-2 ratio, it also decreased cell viability. Taken together, $H_2S$ protects primary cultured mouse hepatocytes against $CoCl_2$-induced cell injury through inhibition of the ROS-activated p38 MAPK cascade and the COX-2 pathway.

Development of New Molecular Markers for the Identification of Male Sterile Cytoplasm in Peppers (Capsicum annuum L.)

  • Min, Woong-Ki;Kim, Byung-Dong;Kim, Sung-Gil;Lee, Sang-Hyeob
    • Horticultural Science & Technology
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    • v.29 no.1
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    • pp.53-60
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    • 2011
  • Cytoplasmic male sterility (CMS) induced by mutant mitochondria genome, has been used for commercial seed production of $F_1$ hybrid cultivars in diverse crops. In pepper (Capsicum annuum L.), two sterile cytoplasm specific gene organization, atp6-2 and coxII were identified. An open reading frame, orf456 nearby coxII gene has been speculated to induce male sterility (MS) by mutagenic analysis. Moreover, molecular markers for atp6-2 and coxII of mitochondrial genotype (mitotype) were developed. However, the Cytoplasmic MS specific markers, atp6SCAR and coxIISCAR markers appeared in both N and S cytoplasms when polymerase chain reaction (PCR) cycles prolonged more than 40 cycles. Since the reported molecular markers were dominant markers, the presence of the faint sterile-specific band in normal cytoplasm may lead to the mis-classification of pepper breeding lines. To solve this problem, one common forward primer and two different reverse primers specific to normal coxII and sterile orf456 genes were designed after analyzing their gene organizations. By using these three primers, N and S coxII specific bands were co-amplified in male-sterile lines, but only normal coxII specific band was amplified in maintainer lines. Since the reverse primer for sterile coxII was specifically designed 275 bp downstream of orf456, relatively stable PCR amplification patterns were observed regardless of the number of PCR cycles. These primer sets easily identified different mitotypes among the divergent breeding lines, commercial cultivars and diverse germplasms.

Inhibitory Effect of Sambucus sieboldiana var. pendula (Nakai) Extract on the mRNA and Protein Expression of iNOS and COX-2 in Raw 264.7 Cells (RAW 264.7 세포에서 말오줌나무 추출물의 iNOS, COX-2 단백질 및 mRNA 발현 억제 효과)

  • Lee, Jin-Young;Yoo, Dan-Hee;Chae, Jung-Woo
    • Microbiology and Biotechnology Letters
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    • v.45 no.2
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    • pp.178-183
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    • 2017
  • This study examined a new functional cosmetic material possessing application possibility of Sambucus sieboldiana var. pendula (Nakai) (SS) extract. For this, we analyzed the toxic effect of the SS extract on macrophages (RAW 264.7 cells) by performing MTT assay. Results of the MTT assay showed ${\geq}100%$ cell viability after treatment with $500{\mu}g/ml$ SS extract. To determine the anti-inflammatory activity of the SS extract, we examined its inhibitory effect on lipopolysaccharide (LPS)-induced NO production in RAW 264.7 cells by performing Griess assay. Result of the Griess assay showed that the SS extract inhibited LPS-induced NO production in a concentration-dependent manner. Next, we examined the effect of the SS extract on the production of proinflammatory factors inducible NOS (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 cells. First, we determined the inhibitory effect of 50, 100, and $500{\mu}g/ml$ SS extract on iNOS and COX-2 protein expression by performing western blot analysis, with ${\beta}$-actin as a positive control. Results of western blotting showed that treatment with $500{\mu}g/ml$ SS extract decreased iNOS and COX-2 protein expression by 31.2% and 54.7%, respectively. Next, we determined the inhibitory effect of 50, 100, and $500{\mu}g/ml$ SS extract on iNOS and COX-2 mRNA expression by performing reverse transcription-polymerase chain reaction (PCR), with GAPDH as a positive control. Results of reverse transcription-PCR showed that treatment with $500{\mu}g/ml$ SS extract decreased the mRNA expression of iNOS and COX-2 by 72.2% and 89%, respectively. These results suggest that the SS extract is a highly valuable natural compound because of its functional components and anti-inflammatory activity.

Identification of Hybrid between the Tiger Grouper Epinephelus fuscoguttatus and the Giant Grouper E. lanceolatus by Analyzing COX I and RAG 2 Sequences (COX I 및 RAG 2 유전자 염기서열 분석에 의한 tiger grouper Epinephelus fuscoguttatus와 giant grouper E. lanceolatus 간 잡종의 동정)

  • Kim, Keun-Sik;Lee, Hyo-Ryeon;Sade, Ahemad;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.26 no.1
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    • pp.70-73
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    • 2014
  • Interspecific hybrids between tiger grouper Epinephelus fuscoguttatus and giant grouper E. lanceolatus were genetically identified based on the partial sequence analysis of mitochondrial cytochrome c oxidase I (COX I) gene and nuclear recombination activating gene 2 (RAG 2) gene. Out of 585 base positions of RAG 2, a total of five nucleotide substitutions were detected between the two parental species (E. fuscoguttatus and E. lanceolatus). The hybrids had two distinct types of RAG 2 sequences corresponding to those of both parental species. Mitochondrial COX I gene sequencing showed that hybrids had sequences identical to E. fuscoguttatus. Molecular data clearly demonstrate that hybridization does occur between E. fuscoguttatus and E. lanceolatus, but with E. fuscoguttatus as the maternal parent.

Signal Transduction Network Leading to COX-2 Induction: A Road Map in Search of Cancer Chemopreventives

  • Surh Young-Joon;Kundu Joydeb Kumar
    • Archives of Pharmacal Research
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    • v.28 no.1
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    • pp.1-15
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    • 2005
  • Cancer is still a major global health concern even after an everlasting strive in conquering this dread disease. Emphasis is now given to chemoprevention to reduce the risk of cancer and also to improve the quality of life among cancer afflicted individuals. Recent progress in molecular biology of cancer has identified key components of the cellular signaling network, whose functional abnormality results in undesired alterations in cellular homeostasis, creating a cellular microenvironment that favors premalignant and malignant transformation. Multiple lines of evidence suggest an elevated expression of cyclooxygenase-2 (COX-2) is causally linked to cancer. In response to oxidative/pro-inflammatory stimuli, turning on unusual signaling arrays mediated through diverse classes of kinases and transcription factors results in aberrant expression of COX-2. Population-based as well as laboratory studies have explored a broad spectrum of chemopreventive agents including selective COX-2 inhibitors and a wide variety of anti-inflammatory phytochemicals, which have been shown to target cellular signaling molecules as underlying mechanisms of chemoprevention. Thus, unraveling signaling pathways regulating aberrant COX-2 expression and targeted blocking of one or more components of those signal cascades may be exploited in searching chemopreventive agents in the future.

Involvement of MAPK activation in chemokine or COX-2 productions by Toxoplasma gondii

  • Kim Ji-Young;Ahn Myoung-Hee;Song Hyun-Ouk;Choi Jong-Hak;Ryu Jae-Sook;Min Duk-Young;Cho Myung-Hwan
    • Parasites, Hosts and Diseases
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    • v.44 no.3
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    • pp.197-207
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    • 2006
  • This experiment focused on MAPK activation in host cell invasion and replication of T. gondii, as well as the expression of CC chemokines, MCP-1 and $MIP-1\alpha$, and enzyme, COX-2/prostaglandin $E_2(PGE_2)$ in infected cells via western blot, $[^3H]-uracil$ incorporation assay, ELISA and RT-PCR. The phosphorylation of ERK1/2 and p38 in infected HeLa cells was detected at 1 hr and/or 6 hr postinfection (PI). Tachyzoite proliferation was reduced by p38 or JNK MAPK inhibitors. MCP-1 secretion was enhanced in infected peritoneal macrophages at 6 hr PI. $MIP-1\alpha$ mRNA was increased in macrophages at 18 hr PI. MCP-1 and $MIP-1\alpha$ were reduced after treatment with inhibitors of ERK1/2 and JNK MAPKs. COX-2 mRNA gradually increased in infected RAW 264.7 cells and the secretion of COX-2 peaked at 6 hr PI. The inhibitor of JNK suppressed COX-2 expression. $PGE_2$ from infected RAW 264.7 cells was increased and synthesis was suppressed by PD98059, SB203580, and SP600125. In this study, the activation of p38, JNK and/or ERK1/2 MAPKs occurred during the invasion and proliferation of T. gondii tachyzoites in HeLa cells. Also, increased secretion and expression of MCP-1, $MIP-1\alpha$, COX-2 and $PGE_2$ were detected in infected macrophages, and appeared to occur via MAPK signaling pathways.

Inhibition of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Activity by $1,2,3,4,6-Penta-Ο-galloyl-{\beta}-D-glucose$ in Murine Macrophage Cells

  • Lee, Sung-Jin;Lee, Ik-Soo;Mar, Woong-Chon
    • Archives of Pharmacal Research
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    • v.26 no.10
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    • pp.832-839
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    • 2003
  • Activated macrophages express inducible isoforms of nitric oxide synthase (iNOS) and cyclooxygenase (COX-2), and produce excessive amounts of nitric oxide (NO) and prostaglandin E$_2$ (PGE$_2$), which play key roles in the processes of inflammation and carcinogenesis. The root of Paeonia lactiflora Pall., and the root cortex of Paeonia suffruticosa Andr., are important Chinese crude drugs used in many traditional prescriptions. 1,2,3,4,6-penta-O-galloyl-$\beta$-D-glucose (PGG) is a major bioactive constituent of both crude drugs. PGG has been shown to possess potent anti-oxidant, anti-mutagenic, anti-proliferative and anti-invasive effects. In this study, we examined the inhibitory effects of 1,2,3,4,6-penta-O-galloyl-$\beta$-D-glucose (PGG) isolated from the root of Paeonia lactiflora Pall. on the COX-2 and iNOS activity in LPS-activated Raw 264.7 cells, COX-1 in HEL cells. To investigate the structure-activity relationships of gallate and gallic acid for the inhibition of iNOS and COX-2 activity, we also examined (-)-epigallocatechin gallate (EGCG), gallic acid, and gallacetophenone. The results of the present study indicated that PGG, EGCG, and gallacetophenone treatment except gallic acid significantly inhibited LPS-induced NO production in LPS-activated macrophages. All of the four compounds significantly inhibited COX-2 activity in LPS-activated macrophages. Among the four compounds examined, PGG revealed the most potent in both iNOS ($IC_{50}$ = 18 $\mu\textrm{g}/mL$) and COX-2 inhibitory activity (PGE$_2$: $IC_{50}$ = 8 $\mu\textrm{g}/mL$ and PGD$_2$: $IC_{50}$ = 12 $\mu\textrm{g}/mL$), respectively. Although further studies are needed to elucidate the molecular mechanisms and structure-activity relationship by which PGG exerts its inhibitory actions, our results suggest that PGG might be a candidate for developing anti-inflammatory and cancer chemopreventive agents.

THE DIFFERENCES IN REGULATION OF COX-2 EXPRESSION BETWEEN ESTROGEN AND ISOFLAVONES

  • Shin, Jang-In;Kim, Jung-Hwan;Park, Ock-Jin
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.05a
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    • pp.148-148
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    • 2001
  • Estrogen is known to exert potent vasodilating effects accompanied with an elevation of cyclooxygenase-2 (COX -2) expression. Structurally similar compounds, isoflavones, have shown in our previous study that they stimulate COX-2 of the heart of animals fed soy isoflavones.(omitted)

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