• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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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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• v.4 no.3
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• pp.219-226
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• 2000

In order to elucidate the role of platelet activating factor (PAF) in the acute lung injury induced by endotoxin (ETX), activities of phospholipase A2, lyso PAF acetyltransferase and oxidative stress by neutrophilic respiratory burst were probed in the present study. To induce acute lung injury, $100\;{\mu}g$ of E.coli ETX (type 0127; B8) was instilled directly into the tracheae of Sprague-Dawley rats. Five hours after the ETX instillation, induction of acute lung injury was confirmed by lung leak index and protein contents in the bronchoalveolar lavage (BAL) fluid. At the same time, lung phospholipase A2 (PLA2) activity and expression of group I and II secretory type PLA2 were examined. In these acutely injured rats, ketotifen fumarate, known as lyso PAF acetyltransferase inhibitor and mepacrine were administered to examine the role of PAF in the pathogenesis of the acute lung injury. To know the effect of the ETX in the synthesis of the PAF in the lungs, lyso PAF acetyltransferase activity and PAF content in the lungs were measured after treatments of ETX, ketotifen fumarate and mepacrine. In addition, the role of neutrophils causing the oxidative stress after ETX was examined by measuring lung myeloperoxidase (MPO) and enumerating neutrophils in the BAL fluid. To confirm the oxidative stress in the lungs, pulmonary contents of malondialdehyde (MDA) were measured. After instillation of the ETX in the lungs, lung leak index increased dramatically (p＜0.001), whereas mepacrine and ketotifen decreased the lung leak index significantly (p＜0.001). Lung PLA2 activity also increased (p＜0.001) after ETX treatment compared with control, which was reversed by mepacrine and ketotifen (p＜0.001). In the examination of expression of group I and II secretory PLA2, mRNA synthesis of the group II PLA2 was enhanced by ETX treatment, whereas ketotifen and WEB 2086, the PAF receptor antagonist, decreased the expression. The activity of the lysoPAF acetyltransferase increased (p＜0.001) after treatment of ETX, which implies the increased synthesis of PAF by the remodelling of lysoPAF in the lungs. Consequently, the contents of the PAF in the lungs were increased by ETX compared with control (p＜0.001), while mepacrine (p＜0.001) and ketotifen (p＜0.01) decreased the synthesis of the PAF in the lungs of ETX treated rats. The infiltration of the neutrophils was confirmed by measuring and enumerating lung MPO and the neutrophils in the BAL fluid respectively. Compared with control, ETX increased lung MPO and number of neutrophils in BAL significantly (p＜0.001) whereas mepacrine and ketotifen decrerased number of neutrophils (p＜0.001) and MPO (p＜0.05, p＜0.001, respectively). The lung MDA contents were also increased (p＜0.001) by ETX treatment, but treatment with mepacrine (p＜0.001) and ketotifen (p＜0.01) decreased the lung MDA contents. Collectively, we conclude that ETX increases PLA2 activity, and that the subsequently increased production of PAF was ensued by the remodelling of the lyso PAF resulting in tissue injury by means of oxidative stress in the lungs.

• Journal of fish pathology
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• v.25 no.1
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• pp.1-10
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• 2012

It has been reported that various anti-oxidant substances stimulate non-specific immune responses in fishes. In this study it was examined whether N-acetylcysteine (NAC), an anti-oxidant glutathione (GSH) precursor, can modulate non-specific immune parameters in 8 different fishes. NAC was intraperitoneally administered at 10 mg/kg to catfish (Silurus asotus), loach (Misgurnus mizolepis), common carp (Cyprinus carpio), crucian carp (Carassius carassius), eel (Anguilla japonica), snakehead (Channa argus), tilapia (Oreochromis niloticus) and mullet (Mugil cephalus). Forty-eight hours later, chemiluminescence (CL) response of head-kidney leukocytes and serum lysozyme activity were assessed. In all fishes except crusian carp and loach, CL responses were amplified by NAC. Lysozyme activity was increased by NAC in all fish species but not in tilapia. This result suggests that NAC stimulates non-specific immune responses in various species, and that such effects may have beneficial significance in aquaculture for practical utilization.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.6
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• pp.460-465
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• 2006

An 8-week feeding trial was conducted to investigate the effects of dietary supplementation with probiotics as a feed additive for Juvenile olive flounder (Paralichthys olivaceus). Three experimental diets supplemented with Bacillus polyfermenticus (BP), Bacillus licheniformis (BL), or Bacillus polyfermenticus plus Saccharomyces cerevisiae, (BP+SC) at $1.0{\times}10^7CFU/kg$ diet on a dry-matter basis were prepared. The basal diet was used as a control. After the 8-week feeding trial, the respiratory burst activity (NBT assay) of fish fed the BP + SC diet was significantly higher than that of fish fed the control diet. Fish fed the BP, BL and BP + SC diets had significantly lower cumulative mortality than did fish fed the control diet after the third day of the challenge test (P<0.05). However, there were no significant differences among fish fed the experimental diets in weight gain, feed efficiency, protein efficiency ratio, hematosomatic index, condition factor, survival rate, or Iysozyme activity. Results could suggest that dietary B. polyfermenticus, B. licheniformis, and B. polyfermenticus +S. cerevisiae enhance nonspecific immunity and disease resistance in juvenile olive flounder.

• Applied Microscopy
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• v.31 no.3
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• pp.275-285
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• 2001

The pulmonary alveolar macrophage is thought to play an important role in the mediation of acute inflammatory lung injury by secretory products including degraded enzymes, cytokines, and reactive oxygen metabolites . This study was conceived to understand the role of alveolar macrophage in oxidative stress induced acute lung injury. To examine the alveolar macrophages and xanthine oxidase (XO) activity in bronchoalveolar lavage fluid (BALF), time-dependent changes of numbers of alveolar macrophages, monocytes and neutrophils in alveolar cavity were counted in association with ultrastructural and cytochemical observations of lung tissue and alveolar cells. The number of monocytes was increased (p<0.001) at 1h after IL-1 treatment compared with that of sham. At 2h after instillation of IL-1, the number of alveolar macrophages was the highest, XO activity in BALF was elevated at 2h after IL-1 instillation and the activity was markedly elevated(p<0.05) at 3h after IL-1 treatment. On the basis of these experimental results, it is suggested that, during early phase of acute lung injury induced by IL-1, alveolar macrophage-derived XO contributes to lung injury earlier than the neutrophilic respiratory burst.

• Journal of Periodontal and Implant Science
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• v.27 no.2
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• pp.425-441
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• 1997

The neuropeptide substance P(SP) has been implicated in the mediation of inflammation and immune-mediated disease such as arthritis. Recently, it was reported that SP was markedly increased around the blood vessels in inflamed gingiva as well as in close association with the inflammatory cell infiltrate. These results support that SP may contribute to the pathophysiology of neuronal inflammation in human periodontal tissues. SP may regulate inflammatory/immune responses by stimulating the proliferation of human T cells, differentiation and antibody-secreting potential of B cells, macrophage respiratory burst, connective tissue proliferation, and the secretion of cytokines from monocytes and T cells. Here, I studied potential role of SP as a costimulatory chemical signal in inflammatory/immune responses, by determining the released proinflammatory cytokines such as $MIP-1{\alpha}$, $IL-1{\beta}$, and IL-6 from culture supernatants of homogeneous immune cell lines. Serum free cell supernatants were concentrated with TCA precipitation, fractionated with SDS-PAGE, and subjected into western blot analysis. Among 15 cell lines tested, macrophage/monocyte cell line RAW264.7 and WRl9m.1 showed the highest level of induction of $MIP-1{\alpha}$ when stimulated with LPS. Discrete IL-6 bands with multiple forms of molecular mass were detected from supernatants of B cell lines A20(32kDa), Daudi(32, 35kDa), and SKW6.4(29kDa), which were expressed constitutively. $IL-1{\beta}$ could not be detected by the method of western blot analysis from supernatants of all cell lines tested except RAW264.7, WRl9m.1, and erythroid cell line K562 which showed the least amount of $IL-{\beta}$ secretion. SP $10^{-9}M$ with suboptimal dose of LPS treatment showed synergistic induction of $MIP-1{\alpha}$ release from RAW264.7 or WR19m.1, and also IL-6 release from A20, but this synergism is not the case in costimulation of RAW264.7 or WRl9m.1 with SP $10^{-9}M$ and TPA. Although treatment of T cell line CTLL-R8 with SP $10^{-7}M$ or PHA+TPA induced modest level of $MIP-1{\alpha}$ secretion, synergism was not observed when they are applied together. These findings all together suggest the possibility of a regulatory role of SP in inflammatory/immune reaction through differential modulation of bioactivities of other chemical cosignals.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.822-835
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• 1997

Background : There have been many in vitro evidences that interleukin-4(IL-4) might be the most important cytokine inducing IgE synthesis from B-cells, and interferon-gamma(IFN-$\gamma$) might be a main cytokine antagonizing IL-4-mediated IgE synthesis. Recently some reports demonstrated that IFN-$\gamma$ might be used as a new therapeutic modality in some allergic diseases with high serum IgE level, such as atopic dermatitis or bronchial asthma. To evaluate the in vivo effect of IFN-$\gamma$ in bronchial asthma we tried a clinical study. Methods : Fifty bronchial asthmatics(serum IgE level over 200 IU/ml) who did not respond to inhaled or systemic corticosteroid treatment, and 17 healthy nonsmoking volunteers were included in this study. The CD 23 expressions of peripheral B-cells, the IL-4 activities of peripheral T-cells, the serum soluble CD23(sCD23) levels, and the superoxide anion(${O_2}^-$) generations by peripheral PMN were compared between bronchial asthmatics and normal subjects. The IL-4 activities of peripheral T-cells were analyzed by T-cell supernatant (T-sup)-induced CD23 expression from tonsil B-cells. In bronchial asthmatics the serum IgE levels and histamine $PC_{20}$ in addition to the above parameters were also compared before and after IFN-$\gamma$ treatment. IFN-$\gamma$ was administered subcutaneously with a weekly dose of 30,000 IU per kilogram of body weight for 4 weeks. Results : The ${O_2}^-$ generations by peripheral PMNs in bronchial asthmatics were higher than normal subjects($8.23{\pm}0.94$ vs $5.00{\pm}0.68\;nmol/1{\times}10^6$ cells, P<0.05), and significantly decreased after IFN-$\gamma$ treatment compared to initial values($3.69{\pm}0.88$ vs $8.61{\pm}1.53\;nmol/1{\times}10^6$ cells, P<0.05). CD23 expression of peripheral B-cells in bronchial asthmatics was higher than normal subjects($47.47{\pm}2.96%$, vs $31.62{\pm}1.92%$, P<0.05), but showed no significant change after IFN-$\gamma$ treatment. The serum sCD23 levels in bronchial asthmatics were slightly higher than normal subjects($191.04{\pm}23.3\;U/ml$ vs $162.85{\pm}4.85\;U/ml$), and 11(64.7%) of 17 patients showed a decreasing pattern in their serum sCD23 levels after IFN-$\gamma$ treatment. However the means of serum sCD23 levels were not different before and after IFN-$\gamma$ treatment. The IL-4 activities of peripheral T-cells in bronchial asthmatics were slightly higher than normal subjects($22.48{\pm}6.81%$ vs $18.90{\pm}2.43%$), and slightly increased after IFN-$\gamma$ treatment($27.90{\pm}2.56%$). Nine(60%) of 15 patients showed a decreasing pattern in their serum IgE levels after IFN-$\gamma$ treatment. And the levels of serum IgE were significantly decreased after IFN-$\gamma$ treatment compared to initial values ($658.67{\pm}120.84\;IU/ml$ vs $1394.32{\pm}314.42\;IU/ml$, P<0.05). Ten(83.3%) of 12 patients showed an improving pattern in bronchial hyperresponsiveness after IFN-$\gamma$ treatment, and the means of histamine $PC_{20}$ were significantly increased after IFN-$\gamma$ treatment compared to initial values ($1.22{\pm}0.29mg/ml$ vs $0.69{\pm}0.17mg/ml$, P<0.05). Conclusion : Our results suggest that IFN-$\gamma$ may be useful as well as safety in the treatment of bronchial asthmatics with high serum IgE level and that in vivo effects of IFN-$\gamma$ may be different from its in vitro effects on the regulations of IgE synthesis or the respiratory burst of PMN.