• 약학회지
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• 제51권5호
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• pp.313-317
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• 2007

A series of luotonin A homologues and their aza-analogues were prepared and evaluated their inhibitory activities on COX-1 and 2 as well as their selectivities on COX-2. The aza-analogue of dimethylene-bridged homologue of luotonin A, 3,3'-dimethylene-2-(1',8'-naphthyrid-2'-yl)-4(3H)-quinazolinone (2b), exhibited strongest inhibitory activity against COX-1 and COX-2 dependent phase of prostaglandin $D_2$ generation in mouse bone marrow-derived mast cells in a concentration-dependent manner with an $IC_{50}$ of 39.3 and $1.89{\mu}M$, respectively. Selectivity of 2b on COX-2 over COX-1 was 21 which implied 2b can be a potential lead for the development of selective COX-2 inhibitor.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.74-79
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• 2004

Little is known about the effect of epigallocatechin-3 gallate (ESCG), a major constituent of green tea, on the expression of cyclooxygenase (COX)-2. Here, we studied the role of phospholipase D (PLD) isozymes in EGCG-induced COX-2 expression. Stimulation of human astrocytoma cells (U87) with EGCG induced formation of phosphatidylbutanol, a specific product of PLD activity, and synthesis of COX-2protein and its product, prostaglandin $E_2$ ($PGE_2$). Pretreatment of cells with 1-butanol, but not 3-butanol, suppressed EGCG-induced COX-2 expression and $PGE_2$ synthesis. Furthermore, evidence that PLD was involved in EGCG-induced COX-2 expression w3s provided by the observations that COX-2 expression was stimulated by over-expression of PLD1 or PLD2 isozymes and treatment with phosphatidic acid(PA), and that prevention of PA dephosphorylation by 1-propranolol significantly potentiated COX-2expression Induced by EGCG. EGCG induced activation of p38 mitogen-activated protein kinase (p38MAPK), and specific Inhibition of p38 MAPK dramatically abolished EGCG-Induced PLD activation, COX-2 expression, and $PGE_2$ formation. Moreover, protein kinase C (PKC) inhibition suppressed EGCG-induced p38 MAPK activation, COX-2 expression, and $PGE_2$ accumulation. The same pathways as those obtained in the astrocytoma cells were active in primary rat astrocytes, suggesting the relevance of the findings. Collectively, our results demonstrate for the first time that PLD isozymes mediate EGCG-induced COX-2 expression through PKC and p38 in immortalized astroglial line and normal astrocyte cells.

• Tuberculosis and Respiratory Diseases
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• 제48권2호
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• pp.191-202
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• 2000

목 적: 기관지 천식은 기도의 과민 반응을 특정으로 하는 기도 내 염증 질환이다. 최근 염증반응에 관여하는 cyclooxygease(COX) 에 대해 90년대 초 새로운 형태의 COX2가 발견되었다. 또한 최근 COX2만을 선택적으로 억제하는 약제가 개발되어 이에 대한 연구가 활발히 진행 중이다. 따라서 저자는 기도 내 염증 반응을 특징으로 하는 기관지 천식에서 COX2 발현 양상과 혈중 프로스타글란딘 E2를 측정하고 COX2 억제제를 사용한 후 COX2 발현, 프로스타글란딘 E2의 변화 및 기도 저항의 변화를 알아보았다. 대상 및 방법: 총 38마리의 Sprague-Dawley 백서(250-300g)를 대상으로 정상 대조군, 천식 대조군, 치료군의 3군으로 나누어 실험하였다. 각 세 군에 대해 제 28 연구일에 즉시형 기관지 수축 반응을 유발시킨 후 기도 저항을 측정하였다. 제 30연구일에 혈장 내 프로스타글란딘 E2 수치를 측정하고 기도 및 폐 실질 내 호산구 침윤 정도 및 COX2 면역 조직 화학 염색에 대한 발색 정도를 image analysis를 통해 확인하였다. 결 과: 기관지 및 폐 실질 내 호산구 침윤은 천식 대조군과 치료군의 두 군간에 통계적으로 유의한 차이가 없었다. COX2 면역 조직 화학 염색 및 혈중 프로스타글란딘 E2 농도에 있어서 정상 대조군, 천식 대조군, 치료군의 세 군에서 통계적으로 유의한 차이가 없었다. 치료군에서 nemesulide 투여 후 OVA으로 즉시형 기관지 수축 반응을 일으킨 상태에서 측정한 기도 저항은 nemesulid를 투여하기 전과 비교해서 통계적으로 유의한 차이가 없었다. 결 론: 결론적으로 COX2는 알레르겐 유발성 천식의 병태 생리에 있어서 주된 경로가 아니며 향후 천식 모델에서 COX2 억제제를 사용한 후 lipoxygenase 의한 대사산물과의 상관 관계와 COX2 억제제의 투여하는 방법에 있어서 투여 용량 또는 투여 횟수를 달리하거나 COX2에 대한 선택성이 더 높은 약제를 투여한 후 기도 내 COX2의 변화에 대한 연구가 필요하리라 사료된다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.94.2-94.2
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• 2003

CJ-11668 is a new potent and selective COX-2 inhibitor. CJ-11668 showed COX-2 inhibition (IC50) of 65nM and selectivity ratio (COX-l/COX-2) of 770 in the cell based assay. In the human whole blood assay, CJ-11668 showed COX-2 inhibition (IC50) of 370nM and selectivity ratio (COX-l/COX-2), 135. The treatment of CJ-11668 (5 mg/kg, p.o) produced a significant inhibition (35%) of inflamed rat paw volume in the carrageenan-induced acute inflammation. CJ-11668 also suppressed the PGE2 level (69% inhibition, 1 mg/kg, p.o) in the zymosan-induced mouse air pouch model after 3 hrs. (omitted)

• IMMUNE NETWORK
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• 제6권3호
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• pp.123-127
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• 2006

Background: Caveolin-1 is a principal component of caveolae membranes in vivo. Although expression of caveolae structure and expression of caveolin family, caveolin-1, -2 and -3, was known in chondrocytes, the functional role of caveolae and caveolins in chondrocytes remains unknown. In this study, we investigated the role of caveolin-1 in articular chondrocytes. Methods: Rabbit articular chondrocytes were prepared from cartilage slices of 2-week-old New Zealand white rabbits by enzymatic digestion. Caveolin-1 cDNA was transfected to articular chondrocytes using LipofectaminePLUS. The cyclooxygenase-2 (COX-2) expression levels were determined by immunoblot analysis, immunostaining, immunohistochemistry, and prostaglandin $E_2\;(PGE_2)$ assay was used to measure the COX-2 activity. Results: Ectopic expression of caveolin-1 induced COX-2 expression and activity, as indicated by immunoblot analysis and $PGE_2$ assay. And also, overexpression of caveolin-1 stimulated activation of p38 kinase and ERK-1/-2. Inhibition of p38 kinase and ERK-1/-2 with SB203580 and PD98059, respectively, led to a dose-dependent decrease COX-2 expression and $PGE_2$ production in caveolin-1-transfected cells. Conclusion: Taken together, our data suggest that ectopic expression of caveolin-1 contributes to the expression and activity of COX-2 in articular chondrocytes through MAP kinase pathway.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 2부
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• pp.1068-1071
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• 2011

Cyclooxygenases (COX)-2 has been highly expressed in a variety of tumor cells and involved inflammatory process, tumor-associated angiogenesis, and vascular functions but the underlying mechanism is not clearly elucidated. We here investigated the molecular mechanism by which COX-2 regulates tumor-associated angiogenesis. In vivo, we injected B16-F1 cells overexpressed with COX-2 or mock in wild type or eNOS-deficient mice. Tumor cells overexpressed with COX-2 increase tumor-associated angiogenesis and tumor growth compared with control cells and that the effect of COX-2 was lower in eNOS-deficient mice than wild type mice. These results may contribute to further understanding of the regulation of angiogenesis by COX during tumor metastasis and inflammation.

• The Korean Journal of Physiology and Pharmacology
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• 제10권3호
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• pp.161-165
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• 2006

NO and cyclooxygenase-2 (COX-2) are contributes to vascular inflammation induced by various stimulation. The mechanism, which explains a linkage between NO and COX-2, could be of importance in promoting pathophysiological conditions of vessel. We investigated the effects of NO donors on the COX-l and COX-2 mRNA/protein expression, as well as the nitrite production in culture medium of vascular smooth muscle cell (VSMC). VSMC was primarily cultured from thoracic aorta of rat. In this experiments, COX-l and COX-2 mRNA/protein expressions were analysed and nitrite productions were investigated using Griess reagent. VSMC did not express COX-2 protein in basal condition (Nonlipopolysaccharide (LPS) stimulated). In LPS-stimulated experiments, after 3 hours of NO donor pretreatment, LPS $10{\mu}g/ml$ was treated for 24 hours. COX-l protein expressions were unchanged by SNP and NOR-3. NOR-3 significantly increased COX-2 mRNA/protein expression under LPS stimulation. In contrast, SNP did not increase COX-2 mRNA/protein expression under LPS stimulation. Nitrite production was higher in NOR-3 treatment than SNP treatment under LPS stimulation. These results suggest that the expression of COX-2 in VSMC is regulated by NOR-3, COX-2 expressions were depending on the types of NO donor and LPS stimulation in VSMC.

• The Korean Journal of Physiology and Pharmacology
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• 제10권1호
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• pp.45-50
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• 2006

Melittin-induced pain model has been known to be very useful for the study of pain mechanism. Melittin-induced nociceptive responses are reported to be modulated by the changes in the activity of excitatory amino acid receptor, calcium channel, spinal serotonin receptor and extracellular signaling-regulated kinase. The present study was undertaken to investigate the role of cyclooxygenase (COX) in the melittin-induced nociception. Changes in mechanical threshold, flinchings and paw thickness were measured before and after intraplantar injection of melittin in the rat hind paw. Also studied were the effects of intraperitonealy administered diclofenac (25 mg & 50 mg/kg), piroxicam (10 mg & 20 mg/kg) and meloxicam (10 mg & 20 mg/kg) on the melittin-induced nociceptions. Intraplantar injection of melittin caused marked reduction of mechanical threshold that was dose-dependently attenuated by non-selective COX inhibitor (diclofenac) and selective COX-1 inhibitor (piroxicam), but not by COX-2 inhibitor (meloxicam). Melittin-induced flinchings were strongly suppressed by non-selective COX and COX-1 inhibitor, but not by COX-2 inhibitor. None of the COX inhibitors had inhibitory effects on melittin-induced increase of paw thickness (edema). These experimental findings suggest that COX-1 plays an important role in the melittin-induced nociceptive responses.

• International Journal of Oral Biology
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• 제31권1호
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• pp.21-26
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• 2006

Periodontopathogens including Porphyromonas gingivalis interact with host periodontal cells and the excessive subsequent host responses contribute a major part to the development of periodontal diseases. Cyclooxygenase(COX)-2-synthesized $PGE_2$ has detrimental activities in terms of periodontal pathogenesis. The present study investigated induction of COX-2 expression by P. gingivalis in human monocytic THP-1 cells. Live P. gingivalis increased expression of COX-2, but not that of COX-1, which was demonstrated at both mRNA and protein levels. Elevated levels of $PGE_2$ were released from P. gingivalis-infected THP-1 cells. Pharma-cological inhibition of p38 mitogen-activated protein kinase(MAPK) and extracellular signal-regulated kinase(ERK) substantially attenuated P. gingivalis-induced COX-2 mRNA expression. Indeed, activation of p38 MAPK and ERK was observed in P. gingivalis-infected THP-1 cells. Also, P. gingivalis induced activation of nuclear $factor-{\kappa}B\;(NF-{\kappa}B)$ which is an important transcription factor for COX-2. These results suggest that COX-2 expression is up regulated in P. gingivalis-infected monocytic cells, at least in part, via p38 MAPK, ERK, and $NF-{\kappa}B$.

• Nutritional Sciences
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• 제8권1호
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• pp.16-22
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• 2005

The present study examined the effects of cyclooxygenase-2 (COX-2) inhibitor celecoxib or soy-isoflavones in the presence of estrogen on apoptosis related gene expression, COX-2 and mapkinase in 48-week old female rats. Expressions of bel-2 and bax proteins, which are known to be involved in the regulation of apoptosis, were investigated in mammary glands and heart tissues. The elevated expression of bel-2 expression was observed in mammary glands of celecoxib supplemented rats as well as soy-isoflavones. The mammary glands bel-2/bax ratio was found to be higher in celecoxib or soy-isoflavones supplemented rats. However, in heart tissues, expression of bel-2 and bax was in the order of control, celecoxib and soy-isoflavones. The up-regulation of COX-2 was observed in celecoxib or soy-isoflavones in mammary glands. 'The similar trend was not displayed with the mapkinase expression. In heart tissues, the down-regulation of COX-2 as well as mapkinase was observed in celecoxib or soy-isoflavones supplemented rats. Soy-isoflavones and celecoxib both had a similar regulatory pattern of bel-2, bax and COX-2 in mammary glands, and in heart tissues, only COX-2 exhibited a similar down-regulatory properly. These findings revealed that in estrogen sufficient state, celecoxib and soy-isoflavones might not exhibit proapoptotic potential or COX-2 inhibition in normal mammary glands.