• Tuberculosis and Respiratory Diseases
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• v.68 no.6
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• pp.334-344
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• 2010

Background: Based on the known immunoregulatory functions of moxifloxacin on phagocytes, the therapeutic effect of moxifloxacin on oleic acid (OA)-induced acute lung injury (ALI) was investigated. Methods: Moxifloxacin (10 mg/kg) was given to male Sprague-Dawley rats that had been given oleic acid (OA, $30{\mu}L$) intravenously. Five hours after OA injection, parameters demonstrating ALI were assessed to measure the effects of moxifloxacin on acute lung injury. Results: The pathological findings of OA-induced ALI's was diminished by moxifloxacin. Through ultrastructural and $CeCl_3$ EM histochemistry, moxifloxacin was confirmed to be effective in decreasing oxidative stress in the lung as well. Indices of ALI, such as lung weight/body weight ratio, protein content in bronchoalveolar lavage fluid, and lung myeloperoxidase were decreased by moxifloxacin. In diaminobenzidine immunohistochemistry, fluorescent immunohistochemistry, and Western blotting of the lung, moxifloxacin had decreased the enhanced expression of secretory phospholipase $A_2$ ($sPLA_2$) by OA. Conclusion: We concluded that moxifloxacin was effective in lessening acute inflammatory pulmonary edema caused by OA, by inhibiting the neutrophilic respiratory burst, which was initiated by the activation of $sPLA_2$.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.67-72
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• 2006

The abnormal proliferation of aortic vascular smooth muscle cells (VSMCs) plays a central role in the pathogenesis of atherosclerosis and restenosis after angioplasty and possibly also in the development of hypertension. The present study was designed to examine the inhibitory effects and the mechanism of luteolin 7-glucoside (L7G) on the platelet-derived growth factor (PDGF)-BB-induced proliferation of VSMCs. L7G significantly inhibited the PDGF-BB-induced proliferation and the DNA synthesis of the VSMCs in a concentration-dependent manner. Pre-incubation of the VSMCs with L7G significantly inhibited the PDGF-BB-induced extracellular signal-regulated kinase 1/2 (ERK1/2), Akt and the phospholipase C $(PLC)-{\gamma}1$ activation. However, L7G had almost no affect on the phosphorylation of $PDGF-{\beta}$ receptor tyrosine kinase, which was induced by PDGF-BB. These results suggest that L7G inhibits the PDGF-BB-induced proliferation of VSMCs via the blocking of $(PLC)-{\gamma}1$, Akt, and ERK1/2 phosphorylation.

• Journal of Life Science
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• v.16 no.1
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• pp.17-21
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• 2006

The effects of Korean and Japanese radishes on inflammatory reaction that involves arachidonic acid cascades were investigated in human epithelial gastric cell. The activities of type I (porcine pancreas) and type II (Crotalus atrox) phospholipase $A_2(PLA_2$) were inhibited by radish. Cyclooxygenase-2 (COX-2) activity was significantly suppressed by radish (p<0.05, p<0.01 and p<0.005). The nitric oxide production was also inhibited by radish. The Korean radish was more effective in inhibition of $PLA_2$ and COX-2 activities and nitric oxide production than Japanease radish. These results indicate that radish has a protective effect on gastric epithelial cell inflammation by suppressing the activities of $PLA_2$ and COX-2 activities and nitric oxide production from gastric epithelial cell.

• Journal of Pharmacopuncture
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• v.9 no.2
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• pp.105-111
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• 2006

Objectives : This study was conducted to carry out Purification of Melittin and other peptide components from Bee Venom using gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis Methods : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. Results : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. The fractions obtained from gel filtration chromatography was analyzed by using SDS-PAGE and propionic acid/urea polyacrylamide gel electrophoresis. The melittin obtained from the gel filtration contained residual amount of phospholipase $A_2$ and a protein with molecular weight of 6,000. The contaminating proteins were removed by the second gel filtration chromatography. Conclusion : Gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis are useful to separate peptide components including melittin from bee venom.

• Biomolecules & Therapeutics
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• v.25 no.2
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• pp.194-201
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• 2017

Lysophosphatidylethanolamine (LPE), a lyso-type metabolite of phosphatidylethanolamine, has been reported to be an intercellular signaling molecule. LPE mobilizes intracellular $Ca^{2+}$ through G-protein-coupled receptor (GPCR) in some cells types. However, GPCRs for lysophosphatidic acid (LPA) were not implicated in the LPE-mediated activities in LPA GPCR overexpression systems or in SK-OV3 ovarian cancer cells. In the present study, in human SH-SY5Y neuroblastoma cells, experiments with $LPA_1$ antagonists showed LPE induced intracellular $Ca^{2+}$ increases in an $LPA_1$ GPCR-dependent manner. Furthermore, LPE increased intracellular $Ca^{2+}$ through pertussis-sensitive G proteins, edelfosine-sensitive-phospholipase C, 2-APB-sensitive $IP_3$ receptors, $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores, and subsequent $Ca^{2+}$ influx across plasma membranes, and LPA acted on $LPA_1$ and $LPA_2$ receptors to induce $Ca^{2+}$ response in a 2-APB-sensitive and insensitive manner. These findings suggest novel involvements for LPE and LPA in calcium signaling in human SH-SY5Y neuroblastoma cells.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.6
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• pp.501-510
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• 2019

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. The global prevalence of pediatric NAFLD from general populations is 7.6%. In obese children, the prevalence is higher in Asia. NAFLD has a strong heritable component based on ethnic difference in the prevalence and clustering within families. Genetic polymorphisms of patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2, and glucokinase regulatory protein (GCKR) are associated with the risk of NAFLD in children. Variants of PNPLA3 and GCKR are more common in Asians. Alterations of the gut microbiome might contribute to the pathogenesis of NAFLD. High fructose intake increases the risk of NAFLD. Liver fibrosis is a poor prognostic factor for disease progression to cirrhosis. Magnetic resonance spectroscopy and magnetic resonance proton density fat fraction are more accurate for steatosis quantification than ultrasound. Noninvasive imaging methods to assess liver fibrosis, such as transient elastography, shear-wave elastography, and magnetic resonance elastography are useful in predicting advanced fibrosis, but they need further validation. Longitudinal follow-up studies into adulthood are needed to better understand the natural history of pediatric NAFLD.

• Biomolecules & Therapeutics
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• v.30 no.1
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• pp.38-47
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• 2022

The present study focused on lithocholic acid (LCA), a secondary bile acid that contributes to cholestatic pruritus. Although recent studies have found that LCA acts on MAS-related G protein-coupled receptor family member X4 (MRGPRX4) in humans, it is unclear which subtypes of MRGPRs are activated by LCA in mice since there is no precise ortholog of human MRGPRX4 in the mouse genome. Using calcium imaging, we found that LCA could activate mouse Mrgpra1 when transiently expressed in HEK293T cells. Moreover, LCA similarly activates mouse Mrgprb2. Importantly, LCA-induced responses showed dose-dependent effects through Mrgpra1 and Mrgprb2. Moreover, treatment with QWF (an antagonist of Mrgpra1 and Mrgprb2), YM254890 (Gα_q inhibitor), and U73122 (an inhibitor of phospholipase C) significantly suppressed the LCA-induced responses, implying that the LCA-induced responses are indeed mediated by Mrgpra1 and Mrgprb2. Furthermore, LCA activated primary cultures of mouse sensory neurons and peritoneal mast cells, suggesting that Mrgpra1 and Mrgprb2 contribute to LCA-induced pruritus. However, acute injection of LCA did not induce noticeable differences in scratching behavior, implying that the pruritogenic role of LCA may be marginal in non-cholestatic conditions. In summary, the present study identified for the first time that LCA can activate Mrgpra1 and Mrgprb2. The current findings provide further insight into the similarities and differences between human and mouse MRGPR families, paving a way to understand the complex roles of these pruriceptors.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.322-322
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• 1994

Gram 음성균의 세포벽 성분인 lipopolysaccharide (LPS)는 생체내에서 각종 생리 활성 물질의 생성을 증진 시킴으로써 내독성 shock등의 병변을 유발하는 것으로 알려져 있다. 이중 prostaglandin (PG)합성 증진 작용에 대해서는 많은 보고가 이루어져 있으나 그 자세한 작용 기전이나 특성등에 대해서는 아직 많은 연구가 되어 있지 않다. 따라서 본 연구에서는 랫드의 폐포 macrophage를 대상으로 하여 LPS의 PG 합성 증진 작용에 대한 특성을 확인코자 하였다. 우선 LPS에 의한 PG 합성 profile을 시간별로 확인한 결과 처리 6 시간 이후에 현저한 합성 증가를 관찰하였으며, 이는 주로 cyclooxygenase의 활성 증가에 기인하는 것으로 추정되었다. LPS는 짧은 시간 동안의 처리에 의해서도 PG 합성을 증진 시켰으나, 양적인 면에서, 장시간 처리에 비해 극히 적었고, 이 작용은 phospholipase $A_2$ 활성 증가에 기인하는 것으로 추정 되었다. LPS에 의한 PG합성 증진 작용은, TNF나 PAF의 생성을 매개로 하지는 않았으며, serum의 존재가 필수적임을 확인하였다. EGF, PDGF 등의 growth factor들은 그 자체로는 PG 합성을 유의적으로 증가시키지는 않았으나 LPS와의 병용 처리에 의해 어느 정도의 증진 작용을 나타내었다. 또한, 정상 랫드 serum도 LPS와의 병용 처리에 의해 PG 합성을 현저히 증가 시켰으며, 따라서, LPS는 serum 중의 각종 growth factor 외에도 LBP등의 serum factor들과의 상호 작용을 통하여 PG합성 증진 작용을 나타내는 것으로 추정 되었다.

• Tuberculosis and Respiratory Diseases
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• v.70 no.6
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• pp.482-489
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• 2011

Background: Based on the assertion that apocynin diminishes acute lung injury (ALI) by inhibition of NADPH oxidase, the effect of apocynin was tested in interleukin-$1{\alpha}$ (IL-1)-induced ALI in rats. Methods: IL-1 was insufflated into the trachea of Sprague-Dawley rats to induce ALI, and apocynin (8 mg/kg) was given intravenously for inhibition of NADPH oxidase. In addition, we determined whether apocynin inhibited generation of superoxide anions from isolated human neutrophils. Five hours after IL-1 instillation, lung injury parameters, expression of cytosolic phospholipase A2 (cPLA2) by cells from bronchoalveolar lavage (BAL), an index of oxidative stress in lung tissues (${\gamma}$-glutamyltranspeptidase, activity), and ultrastructure of alveolar type II (AT II) cells were evaluated. Results: Apocynin decreased the generation of free radicals from phorbol myristate (PMA)-activated neutrophils in vitro, but did not ameliorate ALI. IL-1 induced enhancement of the expression of cPLA2 on neutrophils was not altered by apocynin. Conclusion: Apocynin induced suppression of the generation of superoxide anions from neutrophils by inhibition of NADPH oxidase does not attenuate IL-1-induced ALI in rats.

• BMB Reports
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• v.49 no.4
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• pp.232-237
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• 2016

Mulberry tree twigs (Ramulus mori) contain large amounts of oxyresveratrols and have traditionally been used as herbal medicines because of their anti-inflammatory properties. However, the signaling mechanism by which R. mori exerts its anti-inflammatory action remains to be elucidated. In this study, we observed that R. mori ethanol extracts (RME) exerted an inhibitory effect on the lipopolysaccharide (LPS)-induced production of the pro-inflammatory cytokine interleukin-6 (IL-6) in Raw264.7 macrophage cells. Additionally, RME inhibited IL-6 production by blocking the leukotriene B₄ receptor-2 (BLT2)-dependent-NADPH oxidase 1 (NOX1)-reactive oxygen species (ROS) cascade, leading to anti-inflammatory activity. Finally, RME suppressed the production of the BLT2 ligands LTB4 and 12(S)-HETE by inhibiting the p38 kinase-cytosolic phospholipase A₂-5-/12-lipoxygenase cascade in LPS-stimulated Raw264.7 cells. Overall, our results suggest that RME inhibits the 'BLT2 ligand-BLT2'-linked autocrine inflammatory axis, and that this BLT2-linked cascade is one of the targets of the anti-inflammatory action of R. mori.