• The Korean Journal of Physiology and Pharmacology
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• v.5 no.3
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• pp.279-285
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• 2001

Although only a minority of the infected individuals develops atrophic gastritis and the malignancy, factors governing clinical outcomes subsequent to Helicobacter pylori (H. pylori) infection have not yet been defined. H. pylori infection is characterized by extensive infiltration of neutrophils. Myeloperoxidase (MPO) in neutrophils amplifies the oxidative potential of hydrogen peroxides that induce gastric mucosal damage, thus MPO is suspected to play a role in H. pylori-induced gastric injury. Therefore, we explored the association of host MPO genetic polymorphism with atrophic gastritis upon H. pylori infection. Biopsy specimens taken from the gastric mucosa were examined histologically in 87 patients. The PCR-RFLP assay was used to characterize MPO genotypes. The distributions of MPO genotypes were MPO (G/G) 82% and MPO (G/A) 18%. None of MPO (A/A) genotype was observed. A strong positive correlation between the levels of neutrophil infiltration and gastric atrophy found only in MPO (G/G) but not in MPO (G/A) genotype. These results suggest that MPO genotype is a critical determinant in the pathogenesis of atrophic gastritis subsequent to H. pylori infection. Further works need to clarify the functional relevance of MPO genetic polymorphisms on gastric cell injury.

• Toxicological Research
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• v.20 no.3
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• pp.187-193
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• 2004

This study aimed to determine the association of maternal oxidative stress and adverse pregnancy outcome with serum vitamin C concentration and a myeloperoxidase (MPO) genetic polymorphism during pregnancy. We investigated 450 pregnant women who visited Ewha Womans University Hospital for prenatal care during gestational weeks 24～28. During the second trimester, we measured serum vitamin C levels and urinary 8-hydroxyde-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) as an oxidative stress biomarker. We determined the presence of a maternal MPO polymorphism (G-to-A substitution at nucleotide 463) using a PCR-RFLP assay. We compared the level of oxidative stress and birth weight with the vitamin C concentration and the presence of the MPO polymorphism. The mean level of maternal oxidative stress tended to be higher and the birth weight lower for MPO type A/A than for types A/G and G/G. Vitamin C levels above the 75 percentiles were associated with reduced concentrations of urinary MDA and 8-OHdG but increased birth weight. Our data demonstrate that oxidative stress and neonatal birth weight are associated with the MPO genetic polymorphism, with the association modified by the maternal vita-min C levels.

• The Korean Journal of Pharmacology
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• v.20 no.1 s.34
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• pp.1-11
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• 1984

The present study was performed to determine oxygen metabolites involved in cell-free MPO/$H_2O_2/Cl^-$ system by observing the effects of their scavengers on NADH oxidation and ethylene production from methional by the action of MPO prepared from human leukocytes. It was clearly demonstrated that NADH was oxidized by the cell-free MPO/$H_2O_2/Cl^-$ system as evidenced by complete inhibition of the oxidation of the substrate in the presence of eiher azide or catalase, or by omitting $Cl^-$. The MPO-mediated oxidation of NADH was completely abolished by a $^1O_2$ quencher, DABCO but not by $OH{\cdot}$ scavengers, mannitol, benzoate, formate and methanol. In ethylene assay, no ethylene was detected from methional in the MPO/$H_2O_2/Cl^-$ system with evident production of the gas by xanthine-oxidase and $Cu^{++}-H_2O_2$ systems which are suggested to generate $OH{\cdot}$. From the results obtained, it is concluded that $^1O_2$ is a major mediator with exclusion of $OH{\cdot}$ involvement in the cell-free MPO-mediated oxidation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.1
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• pp.8-22
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• 2010

Objectives : The purpose of this study is to investigate the effects of Gyejijakyakjimo-Tang on the Allergic Contact Dermatitis caused by 2,4-dinitro-chlorobezene(DNCB). Methods : Twenty eight mice were divided into four groups ; normal, control, experimental group A and B. Control and experimental groups were induced allergic contact dermatitis by DNCB. Experimental group A was orally administered the Gyejijakyakjimo-Tang and experimental group B was orally administered the prednisolone. In this study, ear thickness measurement, auricle microphotograph observation, MPO(Myeloperoxidase) activity measurement, Reverse transcription-polymerase chain reaction(RT-PCR) analysis of the mRNA level of TNF-$\alpha$, IL-$1{\beta}$ were performed on these four groups. In addition, the effect of Gyejijakyakjimo-Tang on cell viability and the effect of Gyejijakyakjimo-Tang on the compound 48/80-induced histamine release from HMC and RPMC were measured. Results: 1. Both experimental group A and B had decreased ear thickness compared with control group In contact hypersensitivity assay. 2. In experimental group A, inflammatory edema was similarly observed comparing to control group. Nevertheless, inflammatory edema was obviously reduced in experimental group B. In both experimental group A and B, pathological lesion of dermatitis were alleviated. In addition, the numbers of infiltrated inflammatory cells were decreased compared with control group. 3. Compared to the normal group, there was a noticeable increase in MPO activity in control group. However, in experimental group A and B, it showed remarkable inhibition of the increase in MPO activity comparing with control group. 4. The level of expression of TNF-$\alpha$, IL-$1{\beta}$ in experimental group A and B were meaningfully lower than those in control group. 5. In MTT assay, the concentrations of Gyejijakyakjimo-Tang that were used on the test had no cytotoxicity. 6. Gyejijakyakjimo-Tang dose-dependently inhibited the compound 48/80-induced histamine release from both HMC and RPMC. Conclusions : According to above experiments, Gyejijakyakjimo-Tang was effective on allergic contact dermatitis.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.52-56
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• 2017

Objectives: Neutrophils represent the front line of human defense against infections. Immediately after stimulation, neutrophilic enzymes are activated and produce toxic mediators such as pro-inflammatory cytokines, nitric oxide (NO) and myeloperoxidase (MPO). These mediators can be toxic not only to infectious agents but also to host tissues. Because flavonoids exhibit antioxidant and anti-inflammatory effects, they are subjects of interest for pharmacological modulation of inflammation. In the present study, the effects of rutin on stimulus-induced NO and tumor necrosis factor $(TNF)-{\alpha}$ productions and MPO activity in human neutrophils were investigated. Methods: Human peripheral blood neutrophils were isolated using Ficoll-Hypaque density gradient centrifugation coupled with dextran T500 sedimentation. The cell preparations containing > 98% granulocytes were determined by morphological examination through Giemsa staining. Neutrophils were cultured in complete Roswell Park Memorial Institute (RPMI) medium, pre-incubated with or without rutin ($25{\mu}M$) for 45 minutes, and stimulated with phorbol 12-myristate 13-acetate (PMA). Then, the $TNF-{\alpha}$, NO and MPO productions were analyzed using enzyme-linked immunosorbent assay (ELISA), Griess Reagent, and MPO assay kits, respectively. Also, the viability of human neutrophils was assessed using tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and neutrophils were treated with various concentrations of rutin ($1-100{\mu}M$), after which MTT was appended and incubated at $37^{\circ}C$ for 4 hour. Results: Rutin at concentrations up to $100{\mu}M$ did not affect neutrophil viability during the 4-hour incubation period. Rutin significantly decreased the NO and $TNF-{\alpha}$ productions in human peripheral blood neutrophils compared to PMA-control cells (P < 0.001). Also, MPO activity was significantly reduced by rutin (P < 0.001). Conclusion: In this in vitro study, rutin had an anti-inflammatory effect due to its inhibiting NO and $TNF-{\alpha}$ productions, as well as MPO activity, in activated human neutrophils. Treatment with rutin may be considered as a therapeutic strategy for neutrophil-mediated inflammatory/autoimmune diseases.

• Journal of Pharmacopuncture
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• v.20 no.2
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• pp.127-131
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• 2017

Objectives: Polymorphonuclear neutrophils (PMNs) constitute the first line of defense against invading microbial pathogens. Early events in inflammation involve the recruitment of neutrophils to the site of injury or damage where changes in intracellular calcium can cause the activation of pro-inflammatory mediators from neutrophils including superoxide generation, degranulation and release of myeloperoxidase (MPO), productions of interleukin (IL)-8 and tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$), and adhesion to the vascular endothelium. To address the anti-inflammatory role of flavonoids, in the present study, we investigated the effects of the flavonoids quercetin and vitexin on the stimulus-induced nitric oxide (NO), $TNF-{\alpha}$, and MPO productions in human neutrophils. Methods: Human peripheral blood neutrophils were isolated, and their viabilities were determined by using the Trypan Blue exclusion test. The polymorphonuclear leukocyte (PMNL) preparations contained more than 98% neutrophils as determined by morphological examination with Giemsa staining. The viabilities of cultured neutrophils with various concentrations of quercetin and vitexin ($1-100{\mu}M$) were studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Neutrophils were cultured in complete Roswell Park Memorial Institute (RPMI) medium, pre-incubated with or without quercetin and vitexin ($25{\mu}M$) for 45 min, and stimulated with phorbol 12-myristate 13-acetate (PMA) ($10^{-7}M$). NO production was carried out through nitrite determination by using the Griess method. Also, the $TNF-{\alpha}$ and the MPO productions were measured using enzyme-linked immunosorbent assay (ELISA) kits and MPO assay kits. Results: Neutrophil viability was not affected up to a concentration of $100{\mu}M$ of quercetin or vitexin. Both quercetin and vitexin significantly inhibited $TNF-{\alpha}$, NO, and MPO productions in human neutrophils (P < 0.001). Conclusion:The present study showed that both quercetin and vitexin had significant anti-inflammatory effects. Thus, treatment with either quercetin or vitexin may be considered as a therapeutic strategy for treating patients with neutrophil-mediated inflammatory diseases.

• Tuberculosis and Respiratory Diseases
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• v.60 no.1
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• pp.49-56
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• 2006

배경 : 급성 폐손상은 폐내, 외의 원인질환들에 의해 폐포-모세혈관의 투과성이 증가하며, 폐부종에 의해 급성 저산소성 호흡곤란이 유발되는 증후군이다. 헤파린은 항응고작용 외에 자체적으로 항염증효과를 가지고 있으나, 염증성질환에 헤파린을 투여하면 출혈성 합병증이 발생하기 때문에 실제로 임상에서 이용하는데 제약이 있다. 하지만 헤파린에서 2-O와 3-O sulfate를 제거하면, 항응고 효과가 제거되고 항염증효과는 지니고 있는 비항응고성 헤파린 (nonanticoagulant heparin)으로 변화한다. 본 연구에서는 흰쥐에게 내독소 (LPS)를 투여하거나, 출혈성 쇼크를 일으켜서 유발된 급성폐손상에서 비항응고성 헤파린의 치료효과를 살펴보았다. 방법 : 각 군당 5 마리 이상의 흰쥐 (Balb/c mouse)를 이용하였다. 미정맥 (tail vein)을 통해 생리식염수 또는 비항응고성 헤파린 (50 mg/kg)을 투여한 직후에 내독소를 복강으로 투여하거나 (1 mg/kg), 심장천자를 통해 총 혈액의 1/3 정도로 제거하여 출혈성 쇼크를 유도하여 급성폐손상을 유발하였다. 내독소 투여 또는 출혈성 쇼크 유발 1 시간 후에 흰쥐를 희생시키고 폐를 적출하였고, 폐의 염증성 변화는 사이토카인 ($TNF-{\alpha}$, MIP-2, $IL-1{\beta}$)을 측정하여 살펴보았고, 폐손상의 정도는 myeloperoxidase (MPO) assay와 wet-to-dry weight ratio를 측정하여 알아보았다. 결 과 : 내독소를 투여한 흰쥐의 폐에서 대조군의 폐에 비해 사이토카인의 발현이 증가하고 ($TNF-{\alpha}$; $196.1{\pm}10.8$ vs $83.7{\pm}18.4pg/ml$, MIP-2; $3,000{\pm}725$ vs $187{\pm}26pg/ml$, $IL-1{\beta}$; $6,500{\pm}1167$ vs $266{\pm}25pg/ml$, p<0.05, respectively), 폐의 MPO 활성이 증가하였다 ($27.9{\pm}6.2$ vs $10.5{\pm}2.3U/g$ of lung protein, p<0.05). 출혈성 쇼크를 일으킨 흰쥐의 폐에서 대조군의 폐에 비해 사이토카인의 발현은 증가되지 않았으나, MPO 발현은 증가되었다 ($16.5{\pm}3.2$ vs $10.5{\pm}2.3U/g$ of lung protein, p<0.05). 내독소 투여 또는 출혈성 쇼크에 의해 급성폐손상이 유발된 흰쥐에서 생리적 식염수를 투여하거나 비항응고성 헤파린을 투여한 군 사이에 사이토카인의 발현이나 MPO 활성에 의미있는 차이는 관찰되지 않았다. 결론 : 이상의 결과로 비항응고성 헤파린은 내독소를 투여하거나 출혈성 쇼크를 일으키고 한 시간 뒤에 측정한 흰쥐의 급성폐손상에서 의미있는 치료효과를 보이지 않았다.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.1
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• pp.46-61
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• 2009

Background and Objectives : Allergic Contact Dermatitis is the disease affected by industrialization. The more industrialization advanced, the more materials that could induce the allergic contact dermatitis have been increased. Therefore in oriental medicine, various studies have been performed. The objective of this study is to investigate the effects of Naetakchunkeum-san on the Allergic Contact Dermatitis induced by 2,4-dinitro-chlorobezene(DNCB). Meterial and Methods : Twenty eight mice were divided into four groups ; normal, control, experimental group A and B. Control and experimental group were induced allergic contact dermatitis by DNCB. Experimental group A was orally administered the Naetakchunkeum-san and experimental group B was orally administered the prednisolone. In this study, ear thickness measurement, observation auricle microphotograph, Myeloperoxidase(MPO) activity measurement, Reverse transcription-polymerase chain reaction(RT-PCR) analysis of the mRNA level of $TNF-\alpha$, $IL-1\beta$, $INF-\gamma$ were performed on these four groups. In addition, the effect of Naetakchunkeum-san on cell viability and the effect of Naetakchunkeum-san on the compound 48/80-induced histamine release from HMC and RPMC were measured, Results : 1. In contact hypersensitivity assay, experimental group A and B showed decreased ear thickness compared with control group, 2. In experimental group A, pathological lesion of dermatitis were alleviated. In addition, the numbers of infiltrated cells were reduced, and cleft was not shown compared with control group, In experimental group B, similar results were shown. 3. There was a significant increase in MPO activity in control group compared with normal group, Experimental group A and B significantly inhibited the increase in MPO activity compared with control group. 4, The level of expression of $TNF-\alpha$, $IL-1\beta$, $INF-\gamma$ in experimental group A and B were significantly lower than those in control group. As the internal control, cyclophilin mRNA was also reverse-transcribed and amplified. 5, In MTT assay, there were no statistically significant differences in 100 ${\mu}g/ml$, 200 ${\mu}g/ml$, 500 ${\mu}g/ml$, 1000 ${\mu}g/ml$ Naetakchunkeum-san treated group from 0 ${\mu}g/ml$ Naetakchunkeum-san treated group as determined by the Tukey test. 6. Naetakchunkeum-san dose-dependently inhibited the compound 48/80-induced histamine release from both HMC and RPMC. Conclusions : According to above experiments, Naetakchunkeum-san may be applied to allergic contact dermatitis.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.532-541
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• 2003

Background : Phospholipase $A_2$ ($PLA_2$) has been known to be involved in the pathogenesis of acute lung injury (ALI) including ARDS. Since doxycycline has the property of inhibiting secretory group II $PLA_2$, the therapeutic effect of doxycycline hyclate was investigated for gut ischemia/reperfusion (I/R)-induced ALI in Sprague-Dawley rats. Methods : ALI was induced in Sprague-Dawley rats by clamping of the superior mesenteric artery for 60 min, followed by 120 min of reperfusion. To confirm the pathogenetic mechanisms of this ALI associated with neutrophilic oxidative stress, we measured bronchoalveolar lavage (BAL) protein content and lung MPO, and performed cyto-chemical electron microscopy for detection of free radicals, assay of $PLA_2$ activity and cytochrome-c reduction assay. Results : In gut I/R-induced ALI rats, protein leakage, pulmonary neutrophil accumulation, free radical production and lung $PLA_2$ activity were all increased. These effects were reversed by doxycycline hyclate. Conclusion : Doxycycline appears to be effective in ameliorating the gut I/R-induced ALI by inhibiting $PLA_2$, thereby decreasing the production of free radicals from neutrophils.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.71-78
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• 1997

In an attempt to investigate the role of phospholipase $A_2$($PLA_2$) in interleukin-l (IL-l) induced acute lung injury, mepacrine was tried to inhibit $PLA_2$ in IL-l induced ARDS rats. For confirmation of acute lung injury by IL-l, and to know the role of neutrophils in this injury, lung leak index, lung myeloperoxidase(MPO), number of neutrophils and protein content in the bronchoalveolar lavage (BAL) and wet lung weight were measured. At the same time lung $PLA_2$ was measured to know the effect of IL-l on $PLA_2$ activity. Pulmonary surfactant was also measured for an investigation of type II alveolar cell function. Neutrophil adhesion assay was performed to know the effect of $PLA_2$ inhibition in vitro with human umbilical vein endothelial cells (HUVEC). For precise location of injury by IL-l, morpholgical study was performed by electron microscopy. Five hours after instillation of IL-l (50 ng/rat), lung leak index, protein content, number of neutrophils, lung MPO and wet lung weight were increased significantly. Five hours after IL-l instillation lung $PLA_2$ activity was increased significantly, and increased surfactant release was observed in IL-l induced ARDS rats' BAL. In contrast, in rats given mepacrine and IL-l, there was decrease of acute lung injury i.e. decrease of lung leak index, wet lung weight, protein content, number of neutrophils in BAL and decreased lung MPO activity. Mepacrine decreased surfactant release also. Interestingly, inhibition of $PLA_2$ decreased adhesion of human neutrophils to HUVEC in vitro. Morphologically, IL-l caused diffuse necrosis of endothelial cells, type I and II epithelial cells and increased the infiltration of neutrophils in the interstitium of the lung but after mepacrine treatment these pathological findings were lessened. On the basis of these experimental results it is suggested that $PLA_2$ has a major role in the pathogenesis of acute lung injury mediated by neutrophil dependent manner in IL-l induced acute lung injury.