• Archives of Pharmacal Research
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• 제22권1호
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• pp.18-24
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• 1999

Various flavonoid derivatives were previously reported to possess the inhibitory activity on cyclooxygenase/lipoxygenase. And these properties of flavonoids might contribute to their anti-inflammatory activity in vivo. In this study, several polyhydroxylated/methoxylated flavonoid derivatives such as oroxylin A. wogonin, skullcapflavone II, tectorigenin and iristectorigenin A were isolated from the medicinal plants. these compounds were evaluated fro their inhibitory effects on cyclooxygenase/lipoxygenase from the homogenate of human platelets in vitro. It was found that isoflavones including daidzein and tectorigenin possessed the inhibitory activity on cycloooxygenase, although the potency of inhibition was far less than that of indomethacin. In addition, oroxylin A, baicalein and wogonin inhibited 12-lipoxygenase activity without affecting cyclooxygenase, which suggested that 5,6,7- or 5,7,8-trisubstitutions of A-ring of flavone gave favorable results. The IC50 values of oroxylin A and NDGA against 12-lipoxygenase were found to be 100 and 1.5 uM, respectively.

• Environmental Analysis Health and Toxicology
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• 제8권3_4호
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• pp.1-5
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• 1993

Using mixed incubation of cultured endothelial cells, cultured fibroblasts, neutrophils activated with PMA and paraquat, the production of superoxide anion, $H_2O$$_2$and lipoxygenase metabolites (5-HETE and 12-HETE) of arachidonate was estimated. The results was as follows: 1. Neutrophils activated with PMA was produced superoxide anion,$H_2O_2$and lipoxygenase metabolites (5-HETE and 12-HETE) of arachidonate. 2. Fibroblasts did not alter the production of superoxide anion and $H_2O_2$ by neutrophils, it was markedly reduced by mixed incubation with endothelial cells. 3. Mixed incubation with endothelial cells significantly augmented the production of 5 or 12-HETEs, but fibroblasts did not. 4. Using mixed incubation of endothelial cells, fibroblasts, neutrophils and paraquat (50ug/m1 and 100ug/m1), the production of superoxide anion, $H_2O_2$and HETEs was significantly increased on both cells at low concentration (50ug/m1), but markedly reduced at high concentration (1001g/m1). 5. Paraquat showed concentration dependent effects on arachidonate lipoxygenase metabolism.

• 한국작물학회지
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• 제52권1호
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• pp.29-35
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• 2007

국내 및 일본에서 육성된 벼 품종을 고온 저장시 저장기간에 따른 발아율, 이화학적 특성, lipoxygenase의 활성 및 이들 상호관계를 검토하였다. 1. 고온저장($35^{\circ}C$)시 발아율, 현미 단백질, 지방산도 및 lipoxygenase 활성은 저장기간 및 품종 간 차이가 크게 있었으며 두 요인의 상호작용도 인정되어 저장기간별 품종 간 차이가 다르게 나타났다. 2. 고온저장에 의한 현미 단백질, 지방산도 및 lipoxygenase 활성은 저장기간이 길수록 증가하였던 반면, 발아율 및 도요식미치는 감소하는 경향이었다. 3. 지방산도와 발아율 간에는 부의 상관이 지방산도와 lipoxygenase의 활성은 정의 상관이 인정되었다. 4. 17개 품종을 발아율, 지방산도 및 lipoxygenase 활성을 고려하여 군집분석을 수행한 결과 2개의 그룹으로 구분되었다. I군에 속하는 품종은 오대벼, 상미벼, 운광벼, 일품벼, 남평벼, 일미벼, 동안벼, 중산벼, 추청벼, 히또메보레, 고시히까리 등 11개 품종으로 비교적 발아율이 높고 지방산도 및 lipoxygenase 활성이 낮았다.

• 한국환경농학회지
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• 제3권2호
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• pp.37-42
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• 1984

화학물질(化學物質)에 의(依)한 서양고추냉이와 사과의 peroxidase 및 정제된 대두(大豆) lipoxygenase 역가저해(力價沮害)를 조사(調査)하였다. 서양고추냉이와 사과의 peroxidase 역가(力價)에 저해효과(沮害效果)를 주는 농약중(農藥中) maneb가 zineb의 효과(效果)보다 컸으며 10,20,30ppm의 처리농도(處理濃度)에서 maneb는 12.5,23.0,34.5%, zineb는 9.5, 17.5,27.5%의 역가저해(力價沮害)를 보였다. Maneb와 zineb의 혼합체(混合體)인 mancozeb 를 500 ppm의 농도(濃度)로 사과나무에 철포(撤布)했을때 사과의 peroxidase 역가변화(力價變化)는 무처리구(無處理區)와 별 차이(差異)가 없었다. 대두(大豆)의 lipoxygenase 역가(力價)에 미치는 영향(影響)은 zineb의 경우 가장 저해도(沮害度)가 컸으며 phosphamidon과 carbofuran 이 또한 저해효과(沮害效果)가 있었다. 그러나 maneb는 저해효과(沮害效果)가 없었다. 10, 20, 30 ppm의 처리농도하(處理濃度下)에서의 lipoxygenase 역가저해도(力價沮害度)는 zineb가 14.0, 27.0, 40.0%, carbofuran이 6.5, 12.5, 20.0% 그리고 phosphamidon이 4.5, 9.0, 13.0%였다. 또한 이들 세농약(農藥)은 $100{\sim}200\;ppm$에서 100% lipoxygenase 역가저해(力價沮害)를 보였다.

• The Korean Journal of Physiology and Pharmacology
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• 제16권5호
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• pp.313-320
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• 2012

In this study, we focused to identify whether eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone), an extract from Artemisia argyi folium, prevents $H_2O_2$-induced injury of cultured feline esophageal epithelial cells. Cell viability was measured by the conventional MTT reduction assay. Western blot analysis was performed to investigate the expression of 5-lipoxygenase by $H_2O_2$ treatment in the absence and presence of inhibitors. When cells were exposed to 600 ${\mu}M$ $H_2O_2$ for 24 hours, cell viability was decreased to 40%. However, when cells were pretreated with 25~150 ${\mu}M$ eupatilin for 12 hours, viability was significantly restored in a concentration-dependent manner. $H_2O_2$-treated cells were shown to express 5-lipoxygenase, whereas the cells pretreated with eupatilin exhibited reduction in the expression of 5-lipoxygenase. The $H_2O_2$-induced increase of 5-lipoxygenase expression was prevented by SB202190, SP600125, or NAC. We further demonstrated that the level of leukotriene $B_4$ ($LTB_4$) was also reduced by eupatilin, SB202190, SP600125, NAC, or nordihydroguaiaretic acid (a lipoxygenase inhibitor) pretreatment. $H_2O_2$ induced the activation of p38MAPK and JNK, this activation was inhibited by eupatilin. These results indicate that eupatilin may reduce $H_2O_2$-induced cytotoxicity, and 5-lipoxygenase expression and $LTB_4$ production by controlling the p38 MAPK and JNK signaling pathways through antioxidative action in feline esophageal epithelial cells.

• 한국식품과학회지
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• 제19권4호
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• pp.295-299
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• 1987

유안염석과 column chromatography 및 gel여과등으로 비활성이 23.4U/mg이 되는 정제된 mungbean lipoxygenase를 12%의 수율로 얻었다. 정제효소의 작용최적 pH는 8.4이었으며 linoleic acid를 기질로 사용하였을 때 Km값은 0.25mM이었다. 정제효소는 pH $5.0{\sim}7.0$범위와 $50^{\circ}C$이하의 온도에서 비교적 안정하였다. 효소의 활성은 항산화제인 NDGA에 의해 현저히 저해되었고 chelating agents에 의해 저해되었다.

• IMMUNE NETWORK
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• 제9권3호
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• pp.106-113
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• 2009

Background: We previously demonstrated remarkable differences in the expression of IL-8/CXCL8 in aortic tissues and vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) compared to VSMC from normotensive Wistar-Kyoto rats (WKY). In the present study, we investigated the direct effect of IL-8/CXCL8 on expression of 12-lipoxygenase (LO), a hypertensive modulator, in SHR VSMC. Methods: Cultured aortic VSMC from SHR and WKY were used. Expression of 12-LO mRNA was determined by real-time polymerase chain reaction. Phosphorlyation of ERK1/2 and production of 12-LO and angiotensin II subtype 1 ($AT_1$) receptor were assessed by Western blots. IL-8/CXCL8-stimulated DNA synthesis was determined by measuring incorporation of [$^3H$]-thymidine. And effect of IL-8/CXCL8 on vascular tone was determined by phenylephrine-induced contraction of thoracic aortic rings. Results: Treatment with IL-8/CXCL8 greatly increased 12-LO mRNA expression and protein production compared to treatment with angiotensin II. IL-8/CXCL8 also increased the expression of the $AT_1$ receptor. The increase in 12-LO induced by IL-8/CXCL8 was inhibited by treatment with an $AT_1$ receptor antagonist. The induction of 12-LO mRNA production and the proliferation of SHR VSMC by IL-8/CXCL8 was mediated by the ERK pathway. The proliferation of SHR VSMC and the vascular contraction in the thoracic aortic ring, both of which were induced by IL-8/CXCL8, were inhibited by baicalein, a 12-LO inhibitor. Conclusion: These results suggest that the potential role of IL-8/CXCL8 in hypertensive processes is likely mediated through the 12-LO pathway.

• Applied Biological Chemistry
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• 제46권1호
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• pp.23-27
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• 2003

Lipoxygenase는 녹차의 전체적인 품질에 영향을 미치는 "신선하고 풋풋한 풀 향기(green odor)" 향기특성을 가지는 $C_6-alcoho$과 $C_6-aldehyde$ 등 $C_6$화합물을 생성시키는데 관여하는 효소로서 잘 알려져 있다. 본 연구에서는 녹차잎의 초기 성장기간인 4뭘 4에서 15일까지 12일 동안에 매일 채엽한 녹차잎의 lipoxygenase 활성을 측정하고, 이에 따른 $C_6$화합물 및 terpene 등 휘발성 향기성분을 분석하여 수확 날짜에 따른 효소 활성과 녹차잎의 중요한 휘발성 향기성분의 변화를 살펴보았다. 효소활성의 측정은 linoleic acid를 기질로 한 흡광도 측정방법을 사용하였고, 휘발성 향기성분은 Solid Phase MicroExtraction (SPME) 방법으로 휘발성 향기성분을 포집한 후에 GC또는 GC-MS를 이용해 분석하였다. 실험 결과, 초기 녹차 잎 성장기간 동안 lipoxygenase 활성과 $C_6$화합물의 함량은 서로 비례하여 증가 또는 감소하였고, 이러한 변화는 당일의 온도변화와 밀접한 관계가 있는 것으로 나타났다. 즉, 온도가 증가함에 따라서 향기성분의 양도 증가하였으며, 너무 이른 시기에 채엽한 시료는 향기 성분이 매우 적은 것으로 나타났다. 본 연구로부터 "신선한 풀향기"와 "향긋한 꽃향기 (floral)" 등 녹차향 품질에 중요한 영향을 미치는 향 화합물들이 녹차의 초기 채엽기간 중에 어떻게 변화하는지에 대해서 확인 할 수 있었으며, 향기품질이 우수한 녹차를 제조하기 위해서는 생엽 성장 기간동안의 향기성분변화를 이해하는 것이 중요하다는 것을 확인하였다.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1091-1095
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• 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low ($10^{\circ}C$) and room ($25^{\circ}C$)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of $35.49{\pm}2.46$ unit/mg protein during 24 weeks storage at $25^{\circ}C$, followed by LR ($32.73{\pm}1.33$) and MR ($32.66{\pm}1.62$) cultivars. The amounts of fat acidity also were observed by the same order (ER: $20.40{\pm}2.12$>LR: $19.68{\pm}1.86$>MR: $19.64{\pm}1.35$ mg KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: $60.90{\pm}23.47%$, MR: $32.66{\pm}13.95%$, and LR: $32.53{\pm}5.87%$). On the basis of above results, MR cultivars were evaluated the highest quality, because high lipoxygenase activity, high fat acidity, and low germination rate have deteriorated in quality and generated off-odor. Thus, MR cultivars might be very important sources in food processing and stored dietary supplement aspects.

• The Korean Journal of Physiology and Pharmacology
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• 제13권5호
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• pp.385-392
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• 2009

Angiotensin II (Ang II) plays an important role in vascular hypertension. The role of the chemokine CCL5 on Ang II-induced activities in vascular smooth muscle cells (VSMCs) has not been studied. In this study, we elucidated the effect of CCL5 on Ang II-induced 12-lipoxygenase (LO) expression and cell proliferation in spontaneously hypertensive rats (SHR) VSMCs. CCL5 decreased Ang II-induced 12-LO mRNA expression and protein production, and it increased Ang II type 2 ($AT_2$) receptor expression in SHR VSMCs. The inhibitory effect of CCL5 on Ang II-induced 12-LO mRNA expression was mediated through the $AT_2$ receptor. Although treatment of CCL5 alone induced SHR VSMCs proliferation, CCL5 inhibited Ang II-induced VSMCs proliferation and PD123,319, an $AT_2$ receptor antagonist, blocked the inhibitory effect of CCL5 on Ang II-induced VSMCs proliferation. Phosphorylation of p38 was detected in VSMCs treated with Ang II or CCL5 alone. But, decrease of p38 phosphorylation was detected in VSMCs treated with Ang II and CCL5 simultaneously (Ang II/CCL5) and PD123,319 increased p38 phosphorylation in VSMCs treated with Ang II/CCL5. Therefore, these results suggest that the inhibitory effect of CCL5 on Ang II-induced VSMCs proliferation is mediated by the $AT_2$ receptor via p38 inactivation, and CCL5 may play a beneficial role in Ang II-induced vascular hypertension.