• The Korean Journal of Physiology and Pharmacology
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• 제3권4호
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• pp.405-414
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• 1999

The role of platelet-activating factor (PAF) was investigated in intestinal ischemia/reperfusion (I/R) induced acute lung injury associated with oxidative stress. To induce acute lung injury following intestinal I/R, superior mesenteric arteries were clamped with bulldog clamp for 60 min prior to the 120 min reperfusion in Sprague-Dawley rats. Acute lung injury by intestinal I/R was confirmed by the measurement of lung leak index and protein content in bronchoalveolar lavage (BAL) fluid. Lung leak and protein content in BAL fluid were increased after intestinal I/R, but decreased by WEB 2086, the PAF receptor antagonist. Furthermore, the pulmonary accumulation of neutrophils was evaluated by the measurement of lung myeloperoxidase (MPO) activity and the number of neutrophils in the BAL fluid. Lung MPO activity and the number of neutrophils were increased (p＜0.001) by intestinal I/R and decreased by WEB 2086 significantly. To confirm the oxidative stress induced by neutrophilic respiratory burst, gamma glutamyl transferase (GGT) activity was measured. Lung GGT activity was significantly elevated after intestinal I/R (p<0.001) but decreased to the control level by WEB 2086. On the basis of these experimental results, phospholipase $A_2\;(PLA_2),$ lysoPAF acetyltransferase activity and PAF contents were measured to verify whether PAF is the causative humoral factor to cause neutrophilic chemotaxis and oxidative stress in the lung following intestinal I/R. Intestinal I/R greatly elevated $PLA_2$ activity in the lung as well as intestine (p<0.001), whereas WEB 2086 decreased $PLA_2$ activity significantly (p<0.001) in both organs. LysoPAF acetyltransferase activity, the PAF remodelling enzyme, in the lung and intestine was increased significantly (p<0.05) also by intestinal I/R. Accordingly, the productions of PAF in the lung and intestine were increased (p<0.001) after intestinal I/R compared with sham rats. The level of PAF in plasma was also increased (p<0.05) following intestinal I/R. In cytochemical electron microscopy, the generation of hydrogen peroxide was increased after intestinal I/R in the lung and intestine, but decreased by treatment of WEB 2086 in the lung as well as intestine. Collectively, these experimental results indicate that PAF is the humoral mediator to cause acute inflammatory lung injury induced by intestinal I/R.

• The Korean Journal of Physiology and Pharmacology
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• 제15권1호
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• pp.61-66
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• 2011

P2Y receptors are metabotropic G-protein-coupled receptors, which are involved in many important biologic functions in the central nervous system including retina. Subtypes of P2Y receptors in retinal tissue vary according to the species and the cell types. We examined the molecular and pharmacologic profiles of P2Y purinoceptors in retinoblastoma cell, which has not been identified yet. To achieve this goal, we used $Ca^{2+}$ imaging technique and western blot analysis in WERI-Rb-1 cell, a human retinoblastoma cell line. ATP ($10\;{\mu}M$) elicited strong but transient $[Ca^{2+}]_i$ increase in a concentration dependent manner from more than 80% of the WERI-Rb-1 cells (n=46). Orders of potency of P2Y agonists in evoking $[Ca^{2+}]_i$ transients were 2MeS-ATP>ATP>>UTP=${\alpha}{\beta}$-MeATP, which was compatible with the subclass of $P2Y_1$ receptor. The $[Ca^{2+}]_i$ transients evoked by applications of 2MeS-ATP and/or ATP were also profoundly suppressed in the presence of $P2Y_1$ selective blocker (MRS 2179; $30\;{\mu}M$). $P2Y_1$ receptor expression in WERI-Rb-1 cells was also identified by using western blot. Taken together, $P2Y_1$ receptor is mainly expressed in a retinoblastoma cell, which elicits $Ca^{2+}$ release from internal $Ca^{2+}$ storage sites via the phospholipase C-mediated pathway. $P2Y_1$ receptor activation in retinoblastoma cell could be a useful model to investigate the role of purinergic $[Ca^{2+}]_i$ signaling in neural tissue as well as to find a novel therapeutic target to this lethal cancer.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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• pp.462-469
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• 2017

Objective: The aim of this study is to identify genomic regions or genes controlling growth traits in pigs. Methods: Using a panel of 54,148 single nucleotide polymorphisms (SNPs), we performed a genome-wide Association (GWA) study in 562 pure Yorshire pigs with four growth traits: average daily gain from 30 kg to 100 kg or 115 kg, and days to 100 kg or 115 kg. Fixed and random model Circulating Probability Unification method was used to identify the associations between 54,148 SNPs and these four traits. SNP annotations were performed through the Sus scrofa data set from Ensembl. Bioinformatics analysis, including gene ontology analysis, pathway analysis and network analysis, was used to identify the candidate genes. Results: We detected 6 significant and 12 suggestive SNPs, and identified 9 candidate genes in close proximity to them (suppressor of glucose by autophagy [SOGA1], R-Spondin 2 [RSPO2], mitogen activated protein kinase kinase 6 [MAP2K6], phospholipase C beta 1 [PLCB1], rho GTPASE activating protein 24 [ARHGAP24], cytoplasmic polyadenylation element binding protein 4 [CPEB4], GLI family zinc finger 2 [GLI2], neuronal tyrosine-phosphorylated phosphoinositide-3-kinase adaptor 2 [NYAP2], and zinc finger protein multitype 2 [ZFPM2]). Gene ontology analysis and literature mining indicated that the candidate genes are involved in bone, muscle, fat, and lung development. Pathway analysis revealed that PLCB1 and MAP2K6 participate in the gonadotropin signaling pathway and suggests that these two genes contribute to growth at the onset of puberty. Conclusion: Our results provide new clues for understanding the genetic mechanisms underlying growth traits, and may help improve these traits in future breeding programs.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9661-9666
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• 2014

Background: A number of studies have identified a shared susceptibility locus in phospholipase C epsilon 1 (PLCE1) for esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinomas (GCA). However, the results of PLCE1 expression in esophageal and gastric cancer remain inconsistent and controversial. Moreover, the effects on clinicopathological features remain undetermined. This study aimed to provide a precise quantification of the association between PLCE1 expression and the risk of ESCC and GCA through meta-analysis. Materials and Methods: Eligible studies were identified from PubMed, Wanfang Data, ISI Web of Science, and the Chinese National Knowledge Infrastructure databases. Using RevMan5.2 software, pooled odds ratios (ORs) with 95% confidence intervals (CIs) were employed to assess the association of PLCE1 expression with clinicopathological features relative to ESCC or GCA. Results: Seven articles were identified, including 761 esophageal and gastric cancer cases and 457 controls. Overall, we determined that PLCE1 expression was associated with tumor progression in both esophageal cancers (pooled OR=5.93; 95%CI=3.86 to 9.11) and gastric cancers (pooled OR=9.73; 95%CI=6.46 to 14.7). Moreover, invasion depth (pooled OR=3.62; 95%CI=2.30 to 5.70) and lymph node metastasis (pooled OR=4.21; 95%CI=2.69 to 6.59) were linked with PLCE1 expression in gastric cancer. However, no significant associations were determined between PLCE1 overexpression and the histologic grade, invasion depth, and lymph node metastasis in esophageal cancer. Conclusions: Our metaanalysis results indicated that upregulated PLCE1 is significantly associated with an increased risk of tumor progression in ESCC and GCA. Therefore, PLCE1 expression can be appropriately regarded as a promising biomarker for ESCC and GCA patients.

• Journal of Microbiology and Biotechnology
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• 제26권4호
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• pp.730-738
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• 2016

est19 is a gene from Bacillus sp. K91 that encodes a new esterase. A comparison of the amino acid sequence showed that Est19 has typical Ser-Gly-Asn-His (SGNH) family motifs and could be grouped into the SGNH hydrolase family. The Est19 protein was functionally cloned, and expressed and purified from Escherichia coli BL21(DE3). The enzyme activity was optimal at 60℃ and pH 9.0, and displayed esterase activity towards esters with short-chain acyl esters (C₂-C₆). A structural model of Est19 was constructed using phospholipase A1 from Streptomyces albidoflavus NA297 as a template. The structure showed an α/β-hydrolase fold and indicated the presence of the typical catalytic triad Ser49-Asp227-His230, which were further investigated by site-directed mutagenesis. To the best of our knowledge, Est19 is a new member of the SGNH hydrolase family identified from thermophiles, which may be applicable in the industrial production of semisynthetic β-lactam antibiotics after modification.

• 대한약리학회지
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• 제23권1호
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• pp.51-56
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• 1987

본 실험실에서는 회양목(Buxus microphylla var. koreana Nakai)으로 부터 steroid성 alkaloid인 cyclobuxine D를 분리하였고, 그의 여러 약리작용을 검색하고 있다. 본 연구에서는 cyclobuxine D의 guinea pig lung homogenate에서 prostaglandins의 합성에 미치는 영향과 carrageenin으로 유도한 염증에서 prostaglandin의 합성과 백혈구 유주에 대한 영향을 관찰하였다. Cyclobuxine D (up to 100ug/ml)는 guinea pig lung homogenate에 의한 prostaglandins 합성에 대해서는 현저한 영향이 없었으나, 20mg/kg에서 carrageenin으로 유도된 염증에서 prostaglandin의 합성과 백혈구 유주에 대해 현저한 억제작용을 나타낸다. Aspirin은 vivo와 vitro에서 prostaglandin의 합성을 억제하나, 염증 삼출물에서 백혈구 유주에 대해서는 영향이 거의 없다. Dexamethasone은 vitro에서 외인성 arachidcnic acid를 기질로 가했을때는 prostaglandin 합성에 대해 영향이 없었고 carrageenin으로 유도된 염증에서 prostaglandin의 합성과 백혈구 유주를 억제하였다. 이상의 결과로 cyclobuxine D의 항염증작용은 phospholipase $A_2$ activity를 저해하여 항염증 작용을 나타내는 것으로 사료되는 corticosteroid와 유사한 것으로 추정된다.

• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.349-355
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• 2003

We previously shown that LES contraction depends on $M_3$ receptors linked to PTX insensitive $G_q$ protein and activation of PLC. This results in production of $IP_3$, which mediates calcium release, and contraction through a CaM dependent pathway. In the esophagus ACh activates $M_2$ receptors linked to PTX sensitive $G_{i3}$ protein, resulting in activation of PLD, presumably, production of DAG. We investigated the role of PLC isozymes which can be activated by $G_q$ or $G{\beta}$ protein on ACh-induced contraction in LES and esophagus. Immunoblot analysis showed the presence of 3 types of PLC isozymes, $PLC-{\beta}1$, $PLC-{\beta}3$, and $PLC-{\gamma}1$, but not $PLC-{\beta}2$, $PLC-{\beta}4$, $PLC-{\gamma}2$, $PLC-{\delta}1$, and $PLC-{\delta}2$ from both LES and esophageal muscle. ACh produced contraction in a dose dependent manner in LES and esophageal muscle cells obtained by enzymatic digestion with collagenase. $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody incubation reduced contraction in response to ACh in LES but not in esophageal permeabilized cells, but $PLC-{\gamma}1$ antibody incubation did not have an inhibitory effect. The inhibition by $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody on Ach-induced contraction was antibody concentration dependent. The combination with $PLC-{\beta}_1$ and $PLC-{\beta}_3$ antibody completely abolished the contraction, suggesting that $PLC-{\beta}1$ and $PLC-{\beta}3$ have a synergism to inhibit the contraction in LES. $PLC-{\beta}1$, -${\beta}3$ or -${\gamma}1$ antibody did not reduce the contraction of LES cells in response to DAG ($10^{-6}$ M), suggesting that this isozyme of PLC may not activate PKC. When $G_{q/11}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}3$, but not of PLC ${\beta}_1$ was additive (Fig. 6). In contrast, when $G_{\beta}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}_1$, but not of PLC ${\beta}_3$ was additive. This data suggest that $G_{q/11}$/11 or $G{\beta}$ may activate cooperatively different PLC isozyme, $PLC{\beta}_1$ or $PLC{\beta}_3$ respectively.

• The Korean Journal of Physiology and Pharmacology
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• 제2권5호
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• pp.617-628
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• 1998

In order to understand the pathogenetic mechanism of adult respiratory distress syndrome (ARDS), the role of phospholipase A2 (PLA2) in association with oxidative stress was investigated in rats. $Interleukin-1{\alpha}\;(IL-1,\;50\;{\mu}g/rat)$ was used to induce acute lung injury by neutrophilic respiratory burst. Five hours after IL-1 insufflation into trachea, microvascular integrity was disrupted, and protein leakage into the alveolar lumen was followed. An infiltration of neutrophils was clearly observed after IL-1 treatment. It was the origin of the generation of oxygen radicals causing oxidative stress in the lung. IL-1 increased tumor necrosis factor (TNF) and cytokine-induced neutrophil chemoattractant (CINC) in the bronchoalveolar lavage fluid, but mepacrine, a PLA2 inhibitor, did not change the levels of these cytokines. Although IL-1 increased PLA2 activity time-dependently, mepacrine inhibited the activity almost completely. Activation of PLA2 elevated leukotriene C4 and B4 (LTC4 and LTB4), and 6-keto-prostaglandin $F2{\alpha}\;(6-keto-PGF2{\alpha})$ was consumed completely by respiratory burst induced by IL-1. Mepacrine did not alter these changes in the contents of lipid mediators. To estimate the functional changes of alveolar barrier during the oxidative stress, quantitative changes of pulmonary surfactant, activity of gamma glutamyltransferase (GGT), and ultrastructural changes were examined. IL-1 increased the level of phospholipid in the bronchoalveolar lavage (BAL) fluid, which seemed to be caused by abnormal, pathological release of lamellar bodies into the alveolar lumen. Mepacrine recovered the amount of surfactant up to control level. IL-1 decreased GGT activity, while mepacrine restored it. In ultrastructural study, when treated with IL-1, marked necroses of endothelial cells and type II pneumocytes were observed, while mepacrine inhibited these pathological changes. In histochemical electron microscopy, increased generation of oxidants was identified around neutrophils and in the cytoplasm of type II pneumocytes. Mepacrine reduced the generation of oxidants in the tissue produced by neutrophilic respiratory burst. In immunoelectron microscopic study, PLA2 was identified in the cytoplasm of the type II pneumocytes after IL-1 treatment, but mepacrine diminished PLA2 particles in the cytoplasm of the type II pneumocyte. Based on these experimental results, it is suggested that PLA2 plays a pivotal role in inducing acute lung injury mediated by IL-1 through the oxidative stress by neutrophils. By causing endothelial damage, functional changes of pulmonary surfactant and alveolar type I pneumocyte, oxidative stress disrupts microvascular integrity and alveolar barrier.

• Tuberculosis and Respiratory Diseases
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• 제60권4호
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• pp.437-450
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• 2006

연구배경 : 급성호흡곤란증후군의 병인론 중 산화성 스트레스는 페 모세혈관손상의 중요한 기전의 일부이다. 본 연구에서는 호중구에 의한 유리 산소기의 형성이 $PLA_2$의 활성화와 관계가 있음을 근거로 하여 calcium channel blocker인 diltiazem이 내독소에 의한 급성 폐손상에 미치는 영향을 알아보고자 하였다. 방법 : 체중 300 gm 내외의 수컷 Sprague-Dawley흰쥐에서 내독소를 이용하여 급성 폐손상을 유도하고 동시에 내독소 투여 60분전에 diltiazem (3 mg/kg)을 복강 내로 투여하였다. 급성 폐손상이 유도된 흰쥐에서 폐장의 $PLA_2$, 사람에게서 분리된 호중구에서의 $PLA_2$, 폐장의 MPO의 활성도, 폐세척액내의 호중구의 수, surfactant, 단백함량, 호중구에서의 유리 산소기의 생성 등을 측정하였다. 또한 광학 현미경 및 전자 현미경을 이용하여 형태학적인 변화를 관찰하였고, 동시에 전자현미경 세포화학법을 이용하여 폐장내의 유리 산소기의 생성도 검사 하였다. 결과 : 내독소 투여 후 5 시간 후에는 급성 폐손상이 유발되고 폐장 및 호중구의 $PLA_2$, MPO, 폐세척액내의 호중구수, 단백함량 및 surfactant의 함량이 높게 측정되었다. 형태학적으로는 내독소에 의한 급성 페손상이 확인되었고 전자현미경을 이용한 세포화학적 검사에서는 폐장 내 유리 산소기의 생성이 증가되었음을 확인하였다. Diltiazem은 이러한 모든 변화를 감소시키고, 호중구에서의 산소기의 생성도 감소시켜 내독소에 의한 급성 폐손상을 감소 시켰다. 결론 : Diltiazem을 이용한 $PLA_2$의 억제는 내독소에 의한 급성 페손상에서 호중구에 의한 산화성 스트레스를 경감함으로써 그 손상을 줄일 것으로 사료된다.

• 생명과학회지
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• 제25권11호
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• pp.1255-1264
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• 2015

천궁(C. officinale)은 예로부터 민간처방 약재로 사용되었으며, 항염증, 항산화, 항암 및 신생혈관억제 등의 효능을 가지는 것으로 알려져 있다. 하지만 혈구암세포에서 apoptosis 유발과 관련된 분자생물학적 기전에 대해서는 명확히 밝혀져 있지 않다. 본 연구에서는 인체 혈구암세포인 U937 세포에서 천궁의 열수, 에탄올 및 메탄올 추출물(WECO, EECO 및 MECO)이 유발하는 항암효과 및 항암기전을 조사하였다. 먼저 WECO, EECO 및 MECO가 유발하는 증식억제 정도를 조사한 결과 EECO가 가장 뛰어난 효능을 가진다는 것을 알 수 있었으며, 이러한 현상이 apoptosis 유발에 의한 것임을 annexin-V 염색, apoptotic body 형성, DNA 단편화 및 MMP 소실 등을 통하여 확인하였다. EECO 처리에 의한 apoptosis 유발에는 DR4의 발현 증가와 함께 cIAP-1, Bcl-2 및 total Bid의 발현감소가 관여하였으며, caspases-3, -8 및 -9의 활성화와 함께 caspases-3의 기질 단백질인 PARP, β-catenin 및 PLC γ1의 단편화도 관찰되었다. 또한 EECO는 AMPK signaling pathway를 활성화시키는 것으로 나타났으며, AMPK 억제제인 compound C를 이용하여 AMPK의 활성을 억제하였을 경우 EECO에 의하여 유발되었던 apoptosis가 현저하게 감소되는 것으로 나타났다. 이상의 결과를 살펴볼 때 인체 혈구암세포인 U937 세포에서 EECO에 의하여 유발되는 apoptosis는 AMPK가 중요한 조절자로서 작용하는 것으로 생각된다.