• 한국식품위생안전성학회지
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• 제11권4호
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• pp.227-234
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• 1996

This study was designed to characterize endotoxin-induced prostaglandin production in primary cultured rat vascular smooth muscle cells (VSMC). The time course for prostaglandin synthesis in lipopolysaccharide (LPS)-stimulated VSMC showed that the maximum production was reached in 12 hours. LPS induced prostaglandin H2 synthase (PGHS) activity in VSMC and the time course profile in the changes of PGHS activity paralleled that of total prostaglandin production. Differential treatment showed that 4 hours' exposure to LPS was enough for the maximum effect on the prostaglandin production and this effect was completely inhibited by the co-treatment of actinomycin D, a transcription inhibitor. These results suggest that LPS effect might be determined within 4 hours. Actinomycin D increased PGHS activity without affecting prostaglandin production if added 4 hours after LPS treatment. On the other hand, cyclogeximide, a translation inhibitor, augmented LPS-induced prostaglandin production if treated during first four hours, but it inhibited LPS-induced PGHS activity regardless of treatment schedule. These results suggest the existence of multiple regulating mechanisms in the LPS-induced prostaglandin synthesis.

• 대한화장품학회지
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• 제20권1호
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• pp.25-36
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• 1994

Gram 음성균의 세포벽 성분인 lipopolysaccharide는 각종 세포에서의 prostaglandin 합성을 증진 시키며 이는 cyclooxygenase-2의 선택적 발현에 기인한다는 사실이 이미 보고된 바 있다. 본 연구에서는 mouse peritoneal marophage를 대상으로 하여 LPS의 prostaglandin 합성 증진 작용에 대한 특성으로 검토함으로써, COX-2에 대한 선택적 저해제 검색에 이용될 수 있는지 그 가능성을 확인코자 하였다. LPS는 peritoneal macrophage에 처리시 약 8시간 정도의 lag time을 보인 후 prostaglandin 합성을 현저히 증진 시켰으며, 이는 주로 COX 활성의 증가에 기인하는 것으로 추정되었다. 또한 LPS의 작용은 항염증제인 dexamethasone에 의해서 강하게 억제 되었으며 metabolic labeling 결과 이는 COX-2의 생합성을 억제하는데 기인하는 것으로 확인되었다. 따라서 mouse peritoneal macrophage에서의 LPS에 의한 prostaglandin 합성 증진 작용은 rat alveolar macrophage와 정성적으로 동일함을 확인할 수 있었으며, 본 실험 조건은 COX-2에 대한 선택적 저해제 검색에 응용될 수 있음을 확인 하였다. 본 실험 조건하에서 비스테로이드성 항염제인 ketoprofen의 작용을 검토한 결과 ketoprofen은 COX-1에 비교적 선택적인 저해 작용을 보이는 것으로 추정 되었다.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.361-362
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• 1998

• 한국식품위생안전성학회지
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• 제8권4호
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• pp.181-188
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• 1993

It is well known that bacterial lipopolysaccharide (LPS) stimulates the prostaglandin (PG) synthesis in various experimental system, but the mechanism and the detailed nature of its action are yet to be understood. Thus, this study was designed to characterize LPS induced PG synthesis in rat alveolar macrophage. Although results were not so much prominent, LPS stimulated PGE2 synthesis in macrophage with short term exposure, and this was thought to be mainly due to the activation of phopholipase A2+ But there was a burst in the PG synthesis 6 hours after the LPS treatment and this was accompanied with the increase of cyclooxygenase activity. This effect was not mediated by tumor necrosis factor (TNF) or platelet activating factor (PAF), and the existence of serum was prerequisite for its action. Growth factors such as epidermal growth factor (EGF) and platelet derived growth factor (PDGF) themselves did not stimulate PG synthesis and the showed stimulatory activities to some extent. Normal rat serum was more effective for the elicitation of the LPS action than growth factors. Thus, considering the amounts of growth fafctors contained in normal serum, it was suggested that another factors like LPS binding protein (LBP) might be involved in the serum effect on LPS action. Conclusively. it was thought that LPS could stimulate PG synthesis through interaction with serum factors such as EGF, PDGF and/or LBP.

• Journal of Periodontal and Implant Science
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• 제34권2호
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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.

• 약학회지
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• 제41권6호
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• pp.782-788
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• 1997

This study was designed to characterize glucose-enhancing effects on endotoxin-induced prostaglandin production in primary cultured rat vascular smooth muscle cells (VSMC). High glucose treatment significantly augmented prostaglandin (PG) synthesis in lipopolysaccharide (LPS)-stimulated VSMC and this effect was maximal at the concentration of 4mg/ml. It has been reported that increases in glucose metabolism through sorbitol pathway could alter the cytosolic $NADH/NAD^+$ ratio and this change favors de novo synthesis of diacylglycerol (DAG) and, in turn. Results in the activation of protein kinase C (PKC) in vascular tissues. Protein kinase C (PKC) inhibitors, staurosporin and H7, blocked the glucose enhancing effect, and DAG, a PKC activator, significantly increased the PG production stimuated by LPS. Sodium pyruvate, which can reverse the alteration in cytosolic NADH/NAD+ ratio, reduced the high glucose effect on PG production. And also, zopolrestat, a strong aldose reductase inhibitor, almost completely blocked the augmentation effect of glucose on PG synthesis. Arachidonic acid release was significantly increased in high glucose treated group, which implied the increase in $PLA_2$ activity was associated with glucose enhancing effect. Metabloic, labeling study clearly showed that de novo synthesis of prostaglandin H synthase-2 (PGHS-2) is greatly increased in high glucose treated group and this was mitigated by the treatment of zopolrestat. Taken together, the activation of PKC through sorbitol pathway increased the activities of $PLA_2$ and PGHS which resulted in the augmentation in LPS-induced PG production in high glucose treated VSMC.

• 한국동물학회지
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• 제39권3호
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• pp.266-272
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• 1996

봄에 채집한 참개구리의 난소조각 배양계를 사용하여 난자의 배란과정에 프로스타글란딘과 protein kinase C(PKC)가 관여하는 지를 조사하였다. 난소조각을 배양하면서 뇌하수체추출물(FPH) 혹은PKC의 활성제인 12-O-tetradecanoyl phorbol-13-acetate (TPA)를 처리한 후 배란율과 프로스타글란딘의 생상량을 방사면역측정법으로 조사한 결과 농도에 의존하여 난자의 배란이 유도 되었으며 프로스타글란딘의 생성이 촉진되었다. FPH와 TPA에 의한 배란과 프로스타글란딘 생성은, 4월 보다는 5월에 채집한 개구리에서 훨씬 더 효과적이었다. FPH처리는 프로스타글란딘과 함께 progestreone의 생성을 촉진하였으나 TPA는 progestreone의 생성을 촉진하지는 못하였다. FPH와 TPA에 의한 배란과ㅣ 프로스타글라딘 생성 억제제인 indomethacin에 의해서는 난자의 배랑니 억제되지는 않았다. 이러한 결과들은 참개구리 난자의 배란 과정에 PKC의 활성화가 중요한 역할을 하며, 프로스타글라딘의 생성이 매개할 것으로 생각된다.

• 한국식품위생안전성학회지
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• 제8권3호
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• pp.157-161
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• 1993

본 연구는 ethanol의 reactive metabolite인 acetaldehyde의 일차 배양혈관 평활근 세포에 대한 독성 발현 양식을 규명하기 위한 연구의 일환으로, prostaglandin 합성과 세포독성과의 관련성 여부를 확인하기 위하여 수행되었다. Acetaldehyde는, 일차 배양 혈관 평활근 세포에서의 prostaglandin 합성을 현저히 증가 시켰으며, 이때, cyclooxygenase activity 는 큰 변화없거나 오히려 감소시키는 경향을 보였다. Cyclooxygenase inhibitor 인 indometancin은 acetaldehyde에 의한 LDH release를 현저히 차단시켰으며, aspirin 및 salicylic acid는 전혀 영향을 주지 못했다. Phospholipase $A_2\;(PLA_2)$ inhibitor로 알려져 있는 dexamethasone은 유의적인 세포 독성 경감 작용을 보이지 못하였으며, Lipoxygenase inhibitor 들인 NDGA, propyl gallate 등은 현저한 독성 경감 효과를 보였다. 이상의 결과로부터 acetaldehyde에 의한 일차 배양 혈과 평활근 세포에서의 prostaglandin 합성 증가는 Cell death에 대한 직접적인 원인이 아님을 추론할 수 있었으며, $PLA_2/lipoxygenase$ inhibitor들의 강력한 세포독성 경감 작용으로 미루어 볼 때, acetaldehyde 에 의한 세포독성은 lipoxygenase 대사 산물 혹은 $PLA_2$의 직접 작용에 기인할 가능성을 확인할 수 있었다.

• 대한약리학회지
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• 제27권2호
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• pp.183-189
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• 1991

본 연구에서는 흰쥐의 착상지연을 유도하여 착상기간동안 자궁조직내 prostaglandin (PG) 생합성이 어떠한 인자에 의해서 조절되는가를 관찰하여 다음과 같은 결과를 얻었다. 흰쥐의 착상지연과정동안 estradiol을 처리하면 처리후 4시간만에 자궁조직내의 cAMP의 농도가 급격하게 증가하였다. PGE와 $PGF_2{\alpha}$의 농도는 estradiol을 처리한 후 12시간이 경과하였을때 증가하였으나 $PGF_2{\alpha}$의 증가는 통계적으로 유의하지는 않았다. 또한 indomethacin을 estradiol과 동시에 처리하면 estradiol 처리로 인한 PGE와 $PGF_2{\alpha}$의 농도 증가는 나타나지 않았으나 cAMP 농도는 증가하였다. dbcAMP를 처리하면 자궁내 PGE 및 $PGF_2{\alpha}$의 농도가 증가하기 시작하여 estradiol이 투여시에 비하여 4시간 빨리 8시간후에 최고치에 도달하였으며 phosphodiesterase inhibitor인 theophylline을 전처치하면 estradiol만 투여한 것에 비하여 자궁조직내 PGE 및 $PGF_2{\alpha}$의 농도가 유의하게 증가하였다. 이상의 결과로 보아 흰쥐의 착상지연과정동안 estradiol이 자궁의 prostaglandin 합성을 증가시키며 이러한 증가는 cAMP의 증가를 매개하는 것으로 생각된다.

• 생약학회지
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• 제17권2호
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• pp.107-112
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• 1986

The investigation aimed to study the effects of methanol fraction of licorice (FM 100) and glycyrrhizin on prostaglandin synthetase activity, in relation to their analgesic effects. Effects of FM 100 and glycyrrhizin on the activity of prostaglandin synthetase extracted from bull seminal vesicles were examined by the modified method of Takeguchi et al. The analgesic effect of FM 100 was tested in mice by the acetic acid writhing method. FM 100 was administered orally to mice. BSV prostaglandin synthetase activity was inhibited significantly by FM 100 in a dose-dependent manner, whereas the activity was slightly inhibited by glycyrrhizin. Statistically significant analgesic effects were also observed with FM 100. The results suggest that analgesic effect of licorice may be due to the inhibition of prostaglandin synthesis.