• BMB Reports
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• 제35권5호
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• pp.518-523
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• 2002

Nordihydroguaiaretic acid (NDGA), an inhibitor of lipoxygenase, inhibits the secretion of proteins and causes the redistribution of resident Golgi proteins into the endoplasmic reticulum (ER). In this study, the effect of NDGA on lipoprotein lipase (LPL) secretion was investigated in 3T3-L1 adipocytes, and compared with those of brefeldin A (BFA), a well-known fungal metabolite that exhibits similar ER-Golgi redistribution. Both BFA and NDGA blocked secretions of LPL. In the presence of BFA, the active and dimeric LPL was accumulated in adipocytes. After endoglycosidase H (endo H) digestion, the proportion of LPL subunits with partially endo H-sensitive oligosaccharide was significantly increased with BFA. However, in the presence of NDGA, the cellular LPL became inactive, and only the endo H-sensitive fraction of the LPL subunit was observed. An increase of the aggregated forms was observed in the fractions of the sucrose-density gradient ultracentrifugation. These properties of LPL in the NDGA-treated cells were similar to those of LPL that is retained in ER, and the effects of NDGA could not be reversed by BFA. These results indicate that the inhibitory mechanism of NDGA on the LPL secretion is functionally different from the ER-Golgi redistribution that is induced by BFA.

• 대한약리학회지
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• 제29권2호
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• pp.237-244
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• 1993

소 부신수실 크롬친화성 세포(BAMC)에서 $[Met^5]-enkephalin$ (ME)의 분비와 Proenkephalin A (proENK) mRNA의 함량에 대한 nicotine의 영향과 이에 대한 indomethacin, nordihydroguaiaretic acid(NDGA) 및 captopril의 작용을 연구하였다. 10 uM Nicotine으로 BAMC 세포를 장기간 자극시 proENK mRNA의 함량과 배양액으로의 ME 분비가 유의하게 증가하였다. BAMC 세포를 NDGA(lipoxygenase 억제제, 10 uM), indomethacin (cyclooxygenase 억제제), captopril (angiotensin 변환효소 억제제)만으로 처리시에는 ME 분비와 proENK mRNA의 함량에 영향이 없었다. Nicotine에 의한 ME 분비와 proENK mRNA 함량의 증가는 NDGA에 의하여 억제되었다. 그러나 indomethacin과 captopril은 nicotine의 작용에 대하여 아무 영향이 없었다. 이들 결과는 nicotine에 의한 ME 분비와 proENK mRNA 함량의 증가가 부분적으로 lipoxygenase 경로에 의해 매개되며, cyclooxygenase 및 내재성 renin-angiotensin 경로는 관련되지 않음을 나타낸다.

• Journal of Microbiology and Biotechnology
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• 제32권9호
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• pp.1126-1133
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• 2022

This study investigated the contribution of lipoxygenase (LOX) inhibitors, nordihydroguaiaretic acid (NDGA), tetra-O-methyl nordihydroguaiaretic acid (M₄N) and zileuton (ZIL), and thromboxane A2 (TXA₂) inhibitor 4,5-diphenylimidazole (DPI) in the proliferation of Brucella abortus infection. None of the compounds affected the uptake of Brucella into the macrophages. We determined the effect of neutralizing leukotriene B4 (LTB4) receptor and showed that the uptake of the bacteria was inhibited at 30 min post-infection. M₄N treatment attenuated intracellular survival of Brucella at 2 h post-incubation but it was not observed in the succeeding time points. DPI treatment showed reduced survival of Brucella at 24 h post-incubation while blocking LTB4 receptor was observed to have a lower intracellular growth at 48 h post-incubation suggesting different action of the inhibitors in the course of the survival of Brucella within the cells. Reduced proliferation of the bacteria in the spleens of mice was observed in animals treated with ZIL or DPI. Increased serum cytokine level of TNF-α and MCP-1 was observed in mice treated with M₄N or ZIL while a lower IFN-γ level in ZIL-treated mice and a higher IL-12 serum level in DPI-treated mice were observed at 7 d post-infection. At 14 d post-infection, ZIL-treated mice displayed reduced serum level of IL-12 and IL-10. Overall, inhibition of 5-LOX or TXA₂ or a combination therapy promises a potential alternative therapy against B. abortus infection. Furthermore, strong ligands for LTB4 receptor could also be a good candidate for the control of Brucella infection.

• Bulletin of the Korean Chemical Society
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• 제26권7호
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• pp.1117-1120
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• 2005

• 한국동물학회지
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• 제39권3호
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• pp.317-324
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• 1996

파골세포는 골조직을 분해하는 세포로 알려져 있다. 따라서, 파골세포 활성조절은 골조직의 성장과 재조합의 조절에 있어 매우 중요한 의미를 갖는다. 기관배양을 통해 파골세포의 활성을 조절하는 여러가지 인자들이 알려져 있다. 그 중에서 transforming growth factor-$\beta$ (TGF-$\beta$)는 골조직 대사에 중요한 영향을 미치는 것이 알려져 있고, 또한 골조직내에 다량 존재하고 있기 때문에, TGF-$\beta$의 파골세포에 대한 효과를 알아보는 것은 전체 파골작용의 조절기작을 알아보는데 있어 중요한 의미를 갖는다. 본 연구인들은 계배를 이용한 파골세포의 배양법을 개발하였고, 이를 파골세포 활성을 측정하는데 사용하였다. 이 방법을 통해, TGF-$\beta$1이 파골세포의 골분해 활성을 증가시킨다는 것을 알수 있었다. 또한, 이러한 활성작용은 TGF-$\beta$의 파골세포에 대한 직접적인 효과라기 보다는 다른 세포를 통한 간접적인 효과일 가능성이 높다는 사실을 알 수 있었다. TGF-$\beta$에 의한 파골세포의 활성화는 nordihydroguaiaretic acid에 의해 현저하게 저해된 반면, idomethacin에 의해서는 저해되지 않았다. 이러한 실험결과들은 TGF-$\beta$가 arachidonic acid의 lipoxygenase 유도체를 통해 파골세포의 영향을 미칠 가능성을 제시하고 있다.

• Biomolecules & Therapeutics
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• 제20권5호
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• pp.463-469
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• 2012

Atopic dermatitis is a chronic, inflammatory disease of the skin with increased transepidermal water loss. Both an abnormal inflammatory response and a defective skin barrier are known to be involved in the pathogenesis of atopic dermatitis. Protease activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is activated by both trypsin and a specific agonist peptide, SLIGKV-$NH_2$. PAR2 is expressed in suprabasal layers of the epidermis and regulates inflammatory responses and barrier homeostasis. In this study, we show that nordihydroguaiaretic acid (NDGA) inhibits the PAR2-mediated signal pathway and plays a role in skin barrier recovery in atopic dermatitis. Specifically, NDGA reduces the mobilization of intracellular $Ca^{2+}$ in HaCaT keratinocytes by down-regulating inflammatory mediators, such as interleukin-8, thymus and activation-regulated chemokine and intercellular cell adhesion molecule-1 in HaCaT keratinocytes. Also, NDGA decreases the protein expression of involucrin, a differentiation maker of keratinocyte, in both HaCaT keratinocytes and normal human epidermal keratinocytes. We examined NDGA-recovered skin barrier in atopic dermatitis by using an oxazolone-induced atopic dermatitis model in hairless mice. Topical application of NDGA produced an increase in transepidermal water loss recovery and a decrease in serum IgE level, without weight loss. Accordingly, we suggest that NDGA acts as a PAR2 antagonist and may be a possible therapeutic agent for atopic dermatitis.

• Biomolecules & Therapeutics
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• 제17권4호
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• pp.379-387
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• 2009

We have previously reported that N-ethylmaleimide (NEM) induces apoptosis through activation of $K^+$, $Cl^-$-cotransport (KCC) in HepG2 human hepatoblastoma cells. In this study we investigated the possible role of phospholipase $A_2$ ($PLA_2$)-arachidonic acid (AA) signals in the mechanism of the NEM-induced apoptosis. In these experiments we used arachidonyl trifluoromethylketone ($AACOCF_3$), bromoenol lactone (BEL) and p-bromophenacyl bromide (BPB) as inhibitors of the calcium-dependent cytosolic $PLA_2$ ($cPLA_2$), the calcium-independent $PLA_2$ ($iPLA_2$) and the secretory $PLA_2$ ($sPLA_2$), respectively. BEL significantly inhibited the NEM-induced apoptosis, whereas $AACOCF_3$ and BPB did not. NEM increased AA liberation in a dose-dependent manner, which was markedly prevented only by BEL. In addition AA by itself induced $K^+$ efflux, a hallmark of KCC activation, which was comparable to that of NEM. The NEM-induced apoptosis was not significantly altered by treatment with indomethacin (Indo) and nordihydroguaiaretic acid (NDGA), selective inhibitors of cyclooxygenase (COX) and lipoxygenase (LOX), respectively. Treatment with AA or 5,8,11,14-eicosatetraynoic acid (ETYA), a non-metabolizable analogue of AA, significantly induced apoptosis. Collectively, these results suggest that AA liberated through activation of $iPLA_2$ may mediate the NEMinduced apoptosis in HepG2 cells.

• 약학회지
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• 제56권2호
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• pp.80-85
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• 2012

Previously, we have reported that arachidonic acid (AA) appears to be involved in the induction of apoptosis in HepG2 human hepatoblastoma cells. In this study we investigated the possible role of the NADPH oxidase, a membranebound enzyme generating reactive oxygen species (ROS), in the mechanism of AA-induced apoptosis in HepG2 cells. Apoptotic cell death induced by AA was significantly suppressed by various inhibitors of the NADPH oxidase, diphenylene iodonium (DPI), apocynin (Apo) and neopterine (NP). In addition, these inhibitors of the NADPH oxidase completely blunted the AA-induced ROS elevation. Next, we investigated the implication of metabolic pathway of AA in these AA actions. Both apoptosis and ROS production induced by AA were not significantly altered by treatment with indomethacin (Indo) or nordihydroguaiaretic acid (NDGA), selective inhibitors of cyclooxygenase (COX) and lipoxygenase (LOX), respectively, suggesting that AA metabolites produced by COX or LOX may not have an essential role in the AA-induced apoptosis and ROS generation. Collectively, these results suggest that the NADPH oxidase may be a key player in the mechanism of AA-induced apoptosis in HepG2 cells. These results further suggest that NADPH oxidase may be a good target for the management of human hepatomas.

• 대한약리학회지
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• 제26권2호
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• pp.145-152
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• 1990

최근 본 교실에서는 two-bath system을 이용하여 혈관 내피세포에서 superoxide에 의존한 혈관 이완성 물질을 동정하여 발표하였다. 본 실험에서는 상기 system을 이용하여 돼지의 관상동맥 내피세포에서 유리되는 superoxide에 의존한 이완성 물질이 고양이의 흥부 대동맥 내피 및 소의 대동맥 배양내피세포에서 얻어진 이완성 물질에 의한 이완과 매우 유사함을 관찰하여 다음과 같은 결과를 얻었다. 1. 고양이 흥부 대동맥, 돼지 관상동맥의 내피세포 및 소 대동맥 배양 내피세포 등에서 유리되는 superoxide에 의존한 이완 물질은 모두 유사한 이완 작용을 나타내었다. 2. 돼지 관상 동맥 내피세포에서 유리되는 superoxide 의존성 이완 물질이 고양이의 흥부 대동맥 내피세포나 소의 대동맥 배양 내피세포에서 유리되는 이완 물질과는 다소 다른 점도 있었다. 즉, 돼지 관상동맥 내피세포에서 유리되는 이완 물질의 작용은 catalase나 superoxide dismutase(SOD)에 의하여 억제되었으나, 후자의 두 동맥 내피세포에서 유리되는 이완 물질은 SOD에 의해서만 억제되었다. 3. 이러한 이완성 물질들의 생성은 여러 lipoxygenase억제제인 gossypol, nordihydroguaiaretic acid, AA 861 및 eicosatetraynoic acid 등의 전처치에 의하여 봉쇄되었다. 4. Cyclooxygenase 억제제인 indomethacin이 나 cytochrome P-450 monooxygenase 억제제인 proadifen과 cimetidine에 의하여는 봉쇄되지 아니하였다. 이상의 결과로부터 이러한 이완성 물질들은 비록 각기 다른 종의 동물 모델에서 얻었다고 하더라도 장기에 따라 다소 반응의 차이는 있으나 동질성 이완 물질이며, 나아가 이러한 이완성 물질은 여러 조직의 허혈-재관류 손상에 있어서 병리생리학적으로 관련될 것으로 사료된다.

• 통합자연과학논문집
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• 제10권1호
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• pp.1-6
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• 2017

Demand for a new anti-malarial drug has been dramatically increasing in the recent years. Plasmodium falciparum enoyl-acyl carrier protein reductase (PfENR) plays a vital role in fatty acid elongation process, which now emerged as a new important target for the development of anti-microbial and anti-parasitic molecules. In the present study, 19 compounds namely alginic acid, atropine, chlorogenic acid, chrotacumine A & B, coenzyme $Q_1$, 4-coumaric acid, curcumin, ellagic acid, embelin, 5-O-methyl embelin, eugenyl glucoside, glabridin, hyoscyamine, nordihydroguaiaretic acid, rohitukine, scopolamine, tlatlancuayin and ursolic acid were evaluated on their docking behaviour on P. falciparum enoyl-acyl carrier protein reductase (PfENR) using Auto dock 4.2. The docking studies and binding free energy calculations exhibited that glabridin gave the highest binding energy (-8.07 kcal/mol) and 4-coumaric acid in contrast showed the least binding energy (-4.83 kcal/mol). All ligands except alginic acid, ellagic acid, hyoscyamine and glabridin interacted with Gln409 amino acid residue. Interestingly four ligands namely coenzyme $Q_1$, 4-coumaric acid, embelin and 5-O-methyl embelin interacted with Gln409 amino acid residue present in both chains (A & B) of PfENR protein. Thus, the results of this present study exhibited the potential of these 19 ligands as P. falciparum enoyl-acyl carrier protein reductase (PfENR) inhibitory agents and also as anti-malarial agents.