• Tuberculosis and Respiratory Diseases
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• v.49 no.6
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• pp.691-702
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• 2000

Background : Acute lung injury (ALI) is a commonly encountered respiratory disease and its prognosis is poor when the treatment is not provided promptly and properly. However no specific pharmacologic treatment is currently available for ALI, although recently several supportive drugs have been under scrutiny. We studied anti-inflammatory effects of pentoxifylline (PF), a methylated xanthine, and ONO-5046, a synthetic neutrophil elastase inhibitor on lipopolysaccharide (LPS)-induced ALI in vitro. Methods : To establish an in vitro model of LPS-induced ALI, primary rat alveolar macrophages and peripheral neutrophils in various ratios (1:0, 5:1, 1:1, 1:5, 0:1) were co-cultured with transformed rat alveolar epithelial cells (L2 cell line) or vascular endothelial cells (IP2-E4 cell line) under LPS stimulation. Each experiment was divided into five groups-control, LPS, LPS+PF, LPS+ONO, and LPS+PF+ONO. We compared LPS-induced superoxide anion productions from primary rat alveolar macrophages and peripheral neutrophils in various ratios, and the resultant cytotoxicity on L2 cells or IP2-E4 cells between groups. In addition we also compared the productions of tumor necrosis factor (TNF)-$\alpha$ interleukin (IL)-$1{\beta}$, monocyte chemotactic protein(MCP)-1, IL-6, and IL-10 as well as mRNA expressions of TNF-$\alpha$ inducible nitric oxide synthetase(iNOS), and MCP-1 from LPS-stimulated primary rat alveolar macrophages between groups. Results : (1) PF and ONO-5046 in each or both showed a trend to suppress LPS-induced superoxide anion productions from primary rat alveolar macrophages and peripheral neutrophils regardless of their ratio, except for the LPS+PF+ONO group with the 1:5 ratio, although statistical significance was limited to a few selected experimental conditions. (2) PF and ONO-5046 in each or both showed a trend to prevent IP2-E4 cells from LPS-induced cytotoxicity by primary rat alveolar macrophages and peripheral neutrophils regardless their ratio, although statistical significance was limited to a few selected experimental conditions. the effects of PF and/or ONO-5046 on LPS-induced L2 cell cytotoxicity varied according to experimental conditions. (3) PF showed a trend to inhibit LPS-induced productions of INF-$\alpha$ MCP-1, and IL-10 from primary rat alveolar macrophages. ONO-5046 alone didnot affect the LPS-induced productions of proinflammatory cytokines from primary rat alveolar macrophages but the combination of PF and ONO-5046 showed a trend to suppress LPS-induced productions of INF-$\alpha$ and IL-10 PF and ONO-5046 in each or both showed a trend to increase LPS-induced IL-$\beta$ and IL-6 productions from primary rat alveolar macrophages. (4) PF and ONO-5046 in each or both showed a trend to attenuate LPS-induced mRNA expressions of TNF-$\alpha$ and MCP-1 from primary rat alveolar macrophages but at the same time showed a trend increase iNOS mRNA expression. Conclusion : These results suggest that PF and ONO-5046 may play a role in attenuating inflammation in LPS-induced ALI and that further study is needed to use these drugs as a new supportive therapeutic strategy for ALI.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1265-1276
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• 1998

Background : Nitric oxide(NO) is an endogenously produced free radical that plays an important role in regulating vascular tone, inhibition of platelet aggregation and white blood cell adhesion to endothelial cells, and host defense against infection. The highly reactive nature of NO with oxygen radicals suggests that it may either promote or reduce oxidant-induced cell injury in several biological pathways. Oxidant injury and interactions between pulmonary vascular endothelium and leukocytes are important in the pathogenesis of acute lung injury, including acute respiratory distress syndrome(ARDS). In ARDS, therapeutic administration of NO is a clinical condition providing exogenous NO in oxidant-induced endothelial injury. The role of exogenous NO from NO donor or the suppression of endogenous NO production was evaluated in oxidant-induced endothelial injury. Method : The oxidant injury in cultured rat lung microvascular endothelial cells(RLMVC) was induced by hydrogen peroxide generated from glucose oxidase(GO). Cell injury was evaluated by $^{51}$chromium($^{51}Cr$) release technique. NO donor, such as S-nitroso-N-acetylpenicillamine(SNAP) or sodium nitroprusside(SNP), was added to the endothelial cells as a source of exogenous NO. Endogenous production of NO was suppressed with N-monomethyl-L-arginine(L-NMMA) which is an NO synthase inhibitor. L-NMMA was also used in increased endogenous NO production induced by combined stimulation with interferon-$\gamma$(INF-$\gamma$), tumor necrosis factor-$\alpha$(TNF-$\alpha$), and lipopolysaccharide(LPS). NO generation from NO donor or from the endothelial cells was evaluated by measuring nitrite concentration. Result : $^{51}Cr$ release was $8.7{\pm}0.5%$ in GO 5 mU/ml, $14.4{\pm}2.9%$ in GO 10 mU/ml, $32.3{\pm}2.9%$ in GO 15 mU/ml, $55.5{\pm}0.3%$ in GO 20 mU/ml and $67.8{\pm}0.9%$ in GO 30 mU/ml ; it was significantly increased in GO 15 mU/ml or higher concentrations when compared with $9.6{\pm}0.7%$ in control(p < 0.05; n=6). L-NMMA(0.5 mM) did not affect the $^{51}Cr$ release by GO. Nitrite concentration was increased to $3.9{\pm}0.3\;{\mu}M$ in culture media of RLMVC treated with INF-$\gamma$ (500 U/ml), TNF-$\alpha$(150 U/ml) and LPS($1\;{\mu}g/ml$) for 24 hours ; it was significantly suppressed by the addition of L-NMMA. The presence of L-NMMA did not affect $^{51}Cr$ release induced by GO in RLMVC pretreated with INF-$\gamma$, TNF-$\alpha$ and LPS. The increase of $^{51}Cr$ release with GO(20 mU/ml) was prevented completely by adding 100 ${\mu}M$ SNAP. But the add of SNP, potassium ferrocyanate or potassium ferricyanate did not protect the oxidant injury. Nitrite accumulation was $23{\pm}1.0\;{\mu}M$ from 100 ${\mu}M$ SNAP at 4 hours in phenol red free Hanks' balanced salt solution. But nitrite was not detectable from SNP upto 1 mM The presence of SNAP did not affect the time dependent generation of hydrogen peroxide by GO in phenol red free Hanks' balanced salt solution. Conclusion : Hydrogen peroxide generated by GO causes oxidant injury in RLMVC. Exogenous NO from NO donor prevents oxidant injury, and the protective effect may be related to the ability to release NO. These results suggest that the exogenous NO may be protective on oxidant injury to the endothelium.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.52-59
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• 2000

A rapid assay to determine respiration inhibition of Saccharomyces cerevisiae by chemicals was developed. S. cerevisiae was harvested with two different liquid media, yeast extract-peptone-dextrose (YPD) medium capable of occurring both glucose fermentation and mitochondrial respiration, and non-fermentable carbon-yeast extract (NFY) medium capable of occurring respiration only Wells in 96-well plate were loaded with each cell suspension and various concentrations of 46 fungicides with various modes of action. n NFY medium, the non-fermentable carbon source, ethanol (NFY-E medium), glycerol (NFY-G medium) or lactate (NFY-L medium), was used. After incubation for $1{\sim}3$ days, minimum inhibitory concentrations (MICs) of the chemicals were recorded in the media. Of the 46 inhibitors employed in this study, four inhibitors of fungal respiration by blockage of electron flux in the mitochondrial respiratory chain, azoxystrobin, kresoxim-methyl, metominostrobin, and trifloxystrobin, exhibited strong antifungal activity in all of NFY media, but no activity in YPD medium. In contrast to this, five N-trihalomethylthio fungicides showed much stronger antifungal activities in YPD medium than three NFY media. Eleven fungicides inhibited growth of S. cerevisiae in all media and the other 26 fungicides showed no antifungal activity in all media. Thus, our rapid and efficient in vitro method can be considered as an alternative assay system for respiration inhibitor.

• Journal of Life Science
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• v.29 no.7
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• pp.755-761
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• 2019

Kojic acid (KA) is produced by Aspergillus oryzae-sort of like mushrooms, which is commonly called as koji in Japan. KA is used as a chelation agent and a preservative preventing oxidative browning of fruits. KA also shows antibacterial and antifungal properties. Because KA stops the production of melanin by inhibiting tyrosinase in the biosynthetic pathway from tyrosine to melanin in skin, it has been applied as a skin lightening ingredient in cosmetics. Since some animal studies have shown that high amounts of KA had side effects such as in liver, kidney, reproductive, cardiovascular, gastrointestinal, respiratory, brain, and nervous system, more efficient KA derivatives are needed to be developed in order to safely apply as a skin lightening ingredient. A series of KA derivatives via conjugated with triazole by click reaction were synthesized and their in vitro tyrosinase inhibitory activities were evaluated. Most of all KA derivatives have shown in moderate tyrosinase inhibitory activities. In case of KA-hybrid compound, 1~3 have shown tyrosinase inhibitory activities about 50~10,000 times more effective tyrosinase inhibitor compared to KA itself. Specifically, the $IC_{50}$ value of KA-hybrid compound, 2 was $0.0044{\pm}0.74{\mu}M$ against tyrosinase. It is about 10,000 times more effective tyrosinase inhibitor compared to KA itself ($IC_{50}=45.2{\pm}4.6{\mu}M$).

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.193-202
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• 2023

Influenza IAVs are encapsulated negative-strand RNA viruses that infect many bird species' respiratory systems and can spread to other animals, including humans. This work reanalyzed previous microarray datasets to identify common and specific differentially expressed genes (DEGs) in chickens, as well as their biological activities. There were 760 and 405 DEGs detected in HPAIV and LPAIV-infected chicken cells, respectively. HPAIV and LPAIV have 670 and 315 DEGs, respectively, with both viruses sharing 90 DEGs. Because of HPAIV infection, numerous genes were implicated in a fundamental biological function of the cell cycle, according to the functional annotation of DEGs. Of the targeted genes, expressions of CDC Like Kinase 3 (CLK3), Nucleic Acid Binding Protein 1 (NABP1), Interferon-Inducible Protein 6 (IFI6), PIN2 (TERF1) Interacting Telomerase Inhibitor 1 (PINX1), and Cellular Communication Network Factor 4 (WISP1) were altered in DF-1 cells treated with polyinosinic:polycytidylic acid (PIC), a toll-like receptor 3 (TLR3) ligand, suggesting that transcription of these genes be controlled by TLR3 signaling. To gain a better understanding of the pathophysiology of AIVs in chickens, it is crucial to focus more research on unraveling the mechanisms through which AIV infections may manipulate host responses during the infection process. Insights into these mechanisms could facilitate the development of novel therapeutic strategies.

• Journal of Life Science
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• v.20 no.4
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• pp.474-480
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• 2010

Rutin, a group II phospholipase $A_2$ ($PLA_2$) inhibitor, was tested on interleukin-1 (IL-1) induced acute lung injury (ALI) in male Sprague-Dawley rats. Rutin did not alter the increased lung myeloperoxidase activity by IL-1. However, the number of neutrophils in bronchoalveolar lavage fluid (BALF) and IL-1 induced lung leak were decreased by rutin (p<0.001). Simultaneously, rutin decreased lung $PLA_2$ activity, which was increased by IL-1 (p<0.001). The reduction of neutrophilic respiratory burst by the inhibition of $PLA_2$ was confirmed by group II $PLA_2$ inhibitors such as rutin, manoalide and scalaradial. The increased level of cytokine-induced neutrophilic chemoattractant (CINC) in BALF by IL-1 was not affected by rutin. Ultrastructural changes of ALI and increased generation of free radicals in the lung by IL-1 were found, and rutin ameliorated these pathological findings. Taken together, rutin seems to be effective in decreasing IL-1 induced ALI through inhibition of group II $PLA_2$.

• Tuberculosis and Respiratory Diseases
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• v.80 no.2
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• pp.187-193
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• 2017

Background: Third-generation tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR-TKIs) have proved efficacious in treating non-small cell lung cancer (NSCLC) patients with acquired resistance resulting from the T790M mutation. However, since almost 50% patients with the acquired resistance do not harbor the T790M mutation, retreatment with first- or second-generation EGFR-TKIs may be a more viable therapeutic option. Here, we identified positive response predictors to retreatment, in patients who switched to a different EGFR-TKI, following initial treatment failure. Methods: This study retrospectively reviewed the medical records of 42 NSCLC patients with EGFR mutations, whose cancers had progressed following initial treatment with gefitinib or erlotinib, and who had switched to a different first-generation EGFR-TKI during subsequent retreatment. To identify high response rate predictors in the changed EGFR-TKI retreatment, we analyzed the relationship between clinical and demographic parameters, and positive clinical outcomes, following retreatment with EGFR-TKI. Results: Overall, 30 (71.4%) patients received gefitinib and 12 (28.6%) patients received erlotinib as their first EGFR-TKI treatment. Following retreatment with a different EGFR-TKI, the overall response and disease control rates were 21.4% and 64.3%, respectively. There was no significant association between their overall responses. The median progression-free survival (PFS) after retreatment was 2.0 months. However, PFS was significantly longer in patients whose time to progression was ${\geq}10months$ following initial EGFR-TKI treatment, who had a mutation of exon 19, or whose treatment interval was <90 days. Conclusion: In patients with acquired resistance to initial EGFR-TKI therapy, switched EGFR-TKI retreatment may be a salvage therapy for individuals possessing positive retreatment response predictors.

• Tuberculosis and Respiratory Diseases
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• v.70 no.2
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• pp.132-138
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• 2011

Background: Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily. A few studies have examined the role of maspin in tumor suppression of non-small cell lung cancer (NSCLC); however, its role in the development and progression of NSCLC still remains controversial. We evaluated the immunohistochemical expression of maspin in order to elucidate its clinical significance in NSCLC. Methods: We analyzed 145 patients with pathologically confirmed NSCLC, including 66 cases of squamous cell carcinomas (SCCs) and 79 cases of adenocarcinomas (ADCs). We performed a immuno-histochemical stain with maspin and PCNA (proliferating cell nuclear antigen) using tissue microarray blocks. Results: There were 108 men and 37 women in the study population. The mean age of patients in the study was 63.7 years (range, 40.0~82.0; median, 65.0). The proportion of maspin expression was significantly higher in SCCs (52/66, 78.8%; p<0.01) than in ADCs (17/79, 21.5%; p<0.01). Maspin expression was not associated with PCNA (p=0.828), lymph node involvement (p=0.483), or tumor stage (p=0.216), but showed correlation with well-to-moderate tumor differentiation (p=0.012). There was no observed correlation between maspin expression and survival with NSCLC (p=0.218). Conclusion: The present study suggests that maspin expression was significantly higher in SCCs than in ADCs and was associated with low histological grade. However, maspin expression was not an independent factor to predict a prognosis in NSCLC.

• Tuberculosis and Respiratory Diseases
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• v.81 no.4
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• pp.299-304
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• 2018

Background: Roflumilast is the only approved oral phosphodiesterase-4 inhibitor for the treatment of severe chronic obstructive pulmonary disease (COPD) in patients with chronic bronchitis and a history of frequent exacerbations. The purpose of this study was to examine the incidence of adverse effects associated with roflumilast treatment in a real-world setting. Further, we compared the incidence of adverse effects and the discontinuation rate among patients receiving different doses. Methods: We identified all outpatients diagnosed with COPD at Seoul St. Mary's Hospital between May 2011 and September 2016 and retrospectively reviewed their medical records. Roflumilast was prescribed to patients in doses of $500{\mu}g$ and $250{\mu}g$. Results: A total of 269 COPD patients were prescribed roflumilast in our hospital during the study period. Among them, 178 patients were treated with $500{\mu}g$ and 91 patients were treated with $250{\mu}g$. The incidence of adverse effects was 38.2% in the $500{\mu}g$ group and 25.3% in the $250{\mu}g$ group (p=0.034). The discontinuation rate of roflumilast was 41.6% (n=74) in the $500{\mu}g$ group and 23.1% (n=21) in the $250{\mu}g$ group (p=0.003). When adjusted by age, sex, smoking status, and lung function, $500{\mu}g$ dose was significantly associated with the discontinuation of roflumilast (odds ratio, 2.87; p<0.001). Conclusion: There was a lower incidence of adverse effects and discontinuation among patients treated with $250{\mu}g$ compared with $500{\mu}g$ dose. Further studies regarding the optimal dose of roflumilast are required.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.453-462
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• 2002

Background : Matrix metalloproteinases(MMPs) are a large family of proteolytic enzymes, which are involved in the degradation of many different components of the extracellular matrix. There is increasing evidence indicating that individual MMPs have important roles in tumor invasion by inactivating the MMPs. In this study, the correlation between MMPs and TIMPs expression, and the clinical outcome was investigated. Materials and Methods : Immunohistochemical staining of MMP-2, 9 and TIMP-1,2 were performed on paraffin-embedded tumor sections from 74 resected primary non-small cell lung cancers. Results : In 74 patients, MMP-2, MMP-9, TIMP-1, and TIMP-2 immunoreactivity was demonstrated in 24(34%), 19(26%) and 32(43%) of the paraffin-embedded tumors, respectively. The median survival of the MMP-2 positive cases was significantly shorter than that of the negative cases(20 vs 34 months). The median survival of the TIMP-2 positive cases was also was significantly longer than that of the negative cases (34 vs 18 months). The MMP-2, and MMP-9 expression level had a positively correlation with a more advanced stage and lymph node metastasis. There was inverse correlation between TIMP-2 expression and tumor invasion. The median survival of the MMP-2 negative/TIMP-2 positive cases was higher than that of the other cases. Conclusion : These results suggest that tumor invasion and lymph node metastasis are closely related to MMP-2 and MMP-9 expression. There was an inverse correlation between TIMP-2 and MMP-9 expression, and tumor invasion.