• Title/Summary/Keyword: myeloperoxidase

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Involvement of Protein Tyrosine Kinase in Stimulated Neutrophil Responses by Sodium Fluoride

  • Chung, Ki-Kwang;Han, Eun-Sook;Lee, Chung-Soo
    • BMB Reports
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    • v.30 no.2
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    • pp.89-94
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    • 1997
  • In this study, during the activation of neutrophil responses by sodium fluoride. involvement of protein tyrosine kinase was studied. Respiratory burst lysosomal enzyme release and elevation of $[Ca^{2+}]_i$stimulated by sodium fluoride in neutrophils were inhibited by protein kinase inhibitors, genistein and tyrphostin. The inhibitory effect of genistein and tyrphostin on superoxide and $H_{2}O_{2}$ production was less than that of protein kinase C inhibitors, staurosporine and H-7. Staurosporine and H-7 had little or no effect on the release of myeloperoxidase and acid phosphatase stimulated by sodium fluoride. EGTA and verapamil inhibited the elevation of $[Ca^{2+}]_i$ evoked by sodium fluoride. The inhibitory effect of staurosporine on the elevation of $[Ca^{2+}]_i$ was less than that of genistein. Phorbol 12-myristate 13-acetate (PMA)-stimulated superoxide production, which is sensitive to staurosporine, was further enhanced by genistein, whereas the stimulatory action of PMA on myeloperoxidase release was inhibited by genistein. A pretreatment of neutrophils with PMA signifcantly attenuated sodium fluoride-evoked elevation of $[Ca^{2+}]_i$ These results suggest that protein tyrosine kinase may be involved in the activation process of neutrophil responses due to direct stimulation of guanine nucleotide regulatory proteins. In neutrophil responses, PMA-stimulated neutrophils appear to show a different type of inhibition of protein tyrosine kinase.

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Evidence for Singlet Oxygen Involvement in Cell-free Myeloperoxidase/$H_2O_2$/ Chloride Sytem: Exclusion of Hydroxyl Radical Involvement (Cell-free Myeloperoxidase/$H_2O_3$/Chloride System에서 Singlet Oxygen이 관여한다는 실험적 증거)

  • Chung Myung-Hee;Kim Yong-Sik
    • 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.

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Effects of Aspirin on the Pathogenesis of Acute Lung Injury in Rats Subjected to Hemorrhage (출혈성 쇼크로 인한 급성 폐손상의 발병기전과 아스피린의 효과)

  • Park, Yoon-yub;Lee, Young Man
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.1
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    • pp.83-91
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    • 2006
  • Background : For unknown reasons, the serum ferritin concentrations are higher in patients with acute lung injury. A pretreatment with aspirin reduces the acute lung injury in rats subjected severe hemorrhage, and increases the rate of ferritin synthesis in vitro. This study investigated the effect of aspirin on the serum ferritin changes in rats subjected to severe hemorrhage. Methods : Hemorrhagic shock was induced by withdrawing blood (20 ml/kg of B.W.) through the femoral artery for 5 min. The rats were pretreated with aspirin (10 mg/kg, i.v.) 30 min before hemorrhage. Results : The protein content and leukocyte count in the bronchoalveolar lavage fluid, lung tissue myeloperoxidase activities were significantly higher after hemorrhage. The aspirin pretreatment prevented these changes. The serum and lavage fluid ferritin concentrations were elevated higher after hemorrhage. These were also attenuated by the aspirin pretreatment. Conclusion : The changes in the serum and lung lavage ferritin level might be closely related to the severity of hemorrhage-induced acute lung injury. Therefore, the serum and lavage ferritin concentrations can be a useful biomarker for patients with precipitating conditions.

Aspirin Reduces Acute Lung Injury in Rats Subjected to Severe Hemorrhage (Aspirin이 출혈성 쇼크로 인한 급성 폐손상에 미치는 효과)

  • Shin, Tae Rim;Lee, Dong Uk;Park, Yoon-Yub
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.5
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    • pp.522-531
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    • 2003
  • Background : Hemorrhagic shock and trauma are two of the most common causes of acute lung injury. The activation of cyclooxygenase is one of the important causes of acute lung injury. This study investigated the effect of aspirin, a well-known cyclooxygenase inhibitor, on severe hemorrhage-induced acute lung injury in rats. Methods : The hemorrhagic shock was induced by withdrawing blood; 20ml/kg of B.W., through the femoral artery in 5 min. The mean arterial pressure was recorded through the femoral artery on a polygraph. Results : In the present investigation, the lung tissue myeloperoxidase activity, protein contents and leukocyte counts, in bronchoalveolar lavage fluid, increased significantly 2 and 24 h after the hemorrhage induction. Although the decreased mean arterial pressure spontaneously recovered, acute lung injury occurred after severe hemorrhage. These changes were effectively prevented by a single intravenous injection of aspirin (10 mg/kg of B.W.) 30 min before the hemorrhage. Conclusion : These results suggest that severe hemorrhage-induced acute lung injury is mediated, in part, by the activation of cyclooxygenase. Furthermore, pretreatment of aspirin in acute lung injury-prone patients, or prophylactic treatment of aspirin to the patients with precipitating conditions, could be helpful in the prevention of acute lung injury.

Korean Red Ginseng enhances cardiac hemodynamics on doxorubicin-induced toxicity in rats

  • Jang, Young-Jin;Lee, Dongbin;Hossain, Mohammad Amjad;Aravinthan, Adithan;Kang, Chang-Won;Kim, Nam Soo;Kim, Jong-Hoon
    • Journal of Ginseng Research
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    • v.44 no.3
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    • pp.483-489
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    • 2020
  • Background: Korean Red Ginseng (KRG) has been known to possess many ginsenosides. These ginsenosides are used for curing cardiovascular problems. The present study show the protective potential of KRG against doxorubicin (DOX)-induced myocardial dysfunction, by assessing electrocardiographic, hemodynamic, and biochemical parameters and histopathological findings. Methods: Animals were fed a standard chow and adjusted to their environment for 3 days before the experiments. Next, the rats were equally divided into five groups (n = 9, each group). The animals were administered with KRG (250 and 500 mg/kg) for 10 days and injected with DOX (20 mg/kg, subcutaneously, twice at a 24-h interval) on the 8th and 9th day. Electrocardiography and echocardiography were performed to study hemodynamics. Plasma levels of superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde were measured. In addition, the dose of troponin I and activity of myeloperoxidase in serum and cardiac tissue were analyzed, and the histopathological findings were evaluated using light microscopy. Results: Administration of KRG at a dose of 250 and 500 mg/kg recovered electrocardiographic changes, ejection fraction, fractional shortening, left ventricular systolic pressure, the maximal rate of change in left ventricle contraction (-dP/dtmax), and left ventricle relaxation (-dP/dtmax). In addition, KRG treatment significantly normalized the oxidative stress markers in plasma, dose dependently. In addition, the values of troponin I and myeloperoxidase were ameliorated by KRG treatment, dose dependently. And, KRG treatment showed better histopathological findings when compared with the DOX control group. Conclusion: These mean that KRG mitigates myocardial damage by modulating the hemodynamics, histopathological abnormality, and oxidative stress related to DOX-induced cardiomyopathy in rats. The results of the present study show protective effects of KRG on cardiac toxicity.

The effect of Sagunja-tang on TNBS-induced Inflammatory Bowel Disease in Mouse (사군자탕(四君子湯)이 TNBS로 유발(誘發)된 생쥐의 염증성(炎症性) 장질환(腸疾患)에 미치는 영향(影響))

  • Hong, Sang-Sun;Ryu, Bong-Ha;Yoon, Seong-Woo;Kim, Jin-Sung
    • The Journal of Internal Korean Medicine
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    • v.31 no.4
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    • pp.731-751
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    • 2010
  • Objectives : The present study aimed to find out the effect of Sagunja-tang on the prevention and treatment of inflammatory bowel disease using mice with TNBS-induced inflammatory bowel disease. Methods : Mice with TNBS-induced inflammatory bowel disease were medicated with Sagunja-tang, and the weight changes, colon length, lipid peroxidation, and myeloperoxidase activity were observed. Levels of the inflammatory markers interleukin (IL)-$1{\beta}$ and cyclooxygenase-2 (COX-2), its transcription factor activation, phospho-NF-${\kappa}$B (pp65), in the colon by enzyme-linked immunosorbent assay and immunoblot analysis were also measured. Finally, the activation of fecal bacterial enzyme, ${\beta}$-glucuronidase and degradation activation of fecal glycosaminoglycan (GAG) and hyaluronic acid were observed. Results : We found that oral administration of Sagunja-tang inhibited TNBS-induced colon shortening and also inhibited myeloperoxidase activity in the colon of mice as well as IL-$1{\beta}$ and COX-2 expression. Sagunja-tang also inhibited TNBSinduced lipid peroxidation and pp65 activation in the colon of mice. In addition, Sagunja-tang inhibited ${\beta}$-glucuronidase activation and fecal hyaluronic acid degradation activation. Conclusions : It is supposed that Sagunja-tang has a potential therapeutic effect on inflammatory bowel disease through the inhibition of both NF-${\kappa}$B activation and lipid peroxidation, and the improvement of intestinal conditions.

Anticolitic Effect of the Rhizome Mixture of Anemarrhena asphodeloides and Coptidis chinensis (AC-mix) in Mice

  • Jang, Se-Eun;Jeong, Jin-Ju;Hyam, Supriya R.;Han, Myung Joo;Kim, Dong-Hyun
    • Biomolecules & Therapeutics
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    • v.21 no.5
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    • pp.398-404
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    • 2013
  • During a screening program to search the anticolitic herbal medicines, 80% ethanol extract of the rhizome of Anemarrhena asphodeloides (AA) was found to potently inhibit the expression of proinflammatory cytokines TNF-${\alpha}$ and IL-1${\beta}$, as well as the activation of NF-${\kappa}B$ in LPS-stimulated colonic macrophages, followed by that of the rhizome of C. chinensis (CC). AA also potently inhibited TNBS-induced colitic markers, shortening of the colon and increase of macroscopic score, myeloperoxidase activity, TNF-${\alpha}$, IL-1${\beta}$, and IL-6, in mice. The synergistic effect of CC against the anticolitic effect of AA was investigated. CC synergistically inhibited the anticolitic effect of AA. AC-mix (AA+CC, 1:1) potently inhibited them. AC-mix also inhibited the activation of NF-${\kappa}B$, as well as the expression of TNF-${\alpha}$, IL-1${\beta}$, IL-6, iNOS and COX-2. The effects of AC-mix against oxazolone-induced colitis were investigated in mice. AC-mix also potently inhibited oxazolone-induced inflammatory markers, colon shortening, macroscopic score, myeloperoxidase activity, NF-${\kappa}B$ activation and proinflammatory cytokines. Overall, the anti-colitic effect of AC-mix was superior to that of mesalazine. Based on these findings, AC-mix may improve colitis by inhibiting NF-${\kappa}B$ activation.

Effects of Ichungwhan on the Aging Process (이정환(二精丸)이 노화과정에 미치는 영향)

  • Jeong, Ji-Cheon;Hyun, Min-Kyung
    • The Journal of Internal Korean Medicine
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    • v.26 no.2
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    • pp.379-389
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    • 2005
  • Objectives: It is well known that aging and aging-related diseases are linked to the increased level of oxidative stress caused by reactive oxygen species(ROS) and reactive nitrogen species(RNS). Nonprotein-SH decreases during aging, while substances such as ROS, nitric oxide(NO), peroxynitrite($ONOO^-$), myeloperoxidase(MPO), and dityrosine show a significant increase. This study investigated the effect of Ichungwhan on the aging process by examining its effect on the generation of the above-mentioned substances. Methods: Four comparison groups of SD rats were used. They were 6 month-old rats, 24 month-old rats, and 24 month-old rats fed with food containing 0.1% and 0.3% of Ichungwhan extract. The amount of NO, $ONOO^-$, and ROS in the rats' kidneys were examined using a fluorescence microplate reader. The reagents used for this purpose include: dihydrorhodamine 123 (DHR 123), 2',7' -dichlorodihydrofluorescein, diacetate(DCFDA), and 4,5-diaminofluorescein(DAF-2). A spectrophotometer was used to investigate the reactivity of nonprotein-SH and myeioperoxidase(MPO), using reagents such as trichloroacetic acid(TCA) and tetramethylbenzidine(TMB). The amounts of MPO protein and dityrosine were measued by western blot. Results: The observed effects of Ichungwhan on rats were as follows: increase of nonprotein-SH; effective decrease of RNS level by suppression of the generation system of $ONOO^-$ and NO; decrease of ROS level; decrease of the MPO reactivity and the subsequent reduction of amount of MPO protein; retardation of dityrosine formation. It can be hypothesized, therefore, that Ichungwhan affects both the earlier and later phases of the molecular inflammatory process, and retards the aging process. Conclusions: Empirical evidence in this study supports a role for Ichungwhan in generation mechanisms of aging process-linked substances ROS, NO, $ONOO^-$, nonprotein-SH, MPO and dityrosine. Affects contrary to the aging process observed in rats beg further empiricism to investigate potential application of Ichungwhan as a medication for age-related diseases in humans.

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The Effect of Erythropoietin on Ischemia-Reperfusion Injury: An Experimental Study in Rat TRAM Flap Model (백서 복직근판의 허혈-재관류 손상에 대한 Erythropoietin의 영향)

  • Kim, Eun Key;Hong, Joon Pio
    • Archives of Plastic Surgery
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    • v.33 no.5
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    • pp.621-626
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    • 2006
  • Purpose: Erythropoietin is traditionally known to regulate erythropoiesis, but recently its protective effect against ischemia-reperfusion injury has been studied mainly in cardiovascular and neuronal systems. This study was planned to investigate the effects of recombinant human erythropoietin on ischemia-reperfusion injury in rat TRAM flap model. Methods: Superiorly based TRAM flap was elevated and ischemic insult was given for four hours. Thirty minutes before reperfusion, single dose recombinant human Erythropoietin(5000IU/kg) was injected via intraperitoneal route in the treatment group. At 24 hours postoperatively, systemic neutrophil count, tissue myeloperoxidase activity, malonyldialdehyde amount, nitric oxide content, tissue water content and histologic finding of inflammation was evaluated. On 10 days postoperatively, flap survival rate, angiogenesis and change in hematocrit level was evaluated. Results: Tissue nitric oxide level was significantly higher and myeloperoxidase activity was significantly lower in the treatment group 24 hours after reperfusion. Tissue water content was significantly lower in the treatment group. Perivascular neutrophil infiltration and intravascular adhesion was marked in the control group. Mean flap survival after ten days was 69% in the treatment group, and 47% in the control group, demonstrating a significant difference. Neovascularization in the treatment group also outnumbered the control group. No significant hematocrit rise was noted ten days after erythropoietin administration. Conclusion: Recombinant human Erythropoietin improved flap survival in ischemia-reperfusion injured rat TRAM flaps, at least partially owing to suppressed inflammation, increased nitric oxide, and enhanced angiogenesis.

Depression of $Ca^{2+}$ Influx in Complement C5a-stimulated Neutrophils by Calmodulin Inhibitors

  • Ham, Dong-Suk;Kim, Hyun-Ho;Han, Eun-Sook;Lee, Chung-Soo
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.1
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    • pp.109-117
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    • 1998
  • Role of $Ca^{2+}$/calmodulin complex in intracellular $Ca^{2+}$ mobilization in neutrophils has not been clearly elucidated. In this study, effects of chlorpromazine, trifluoperazine and imipramine on the intracellular $Ca^{2+}$ mobilization, including $Ca^{2+}$ influx, in C5a-activated neutrophils were investigated. Complement C5a- stimulated superoxide production and myeloperoxidase release in neutrophils were inhibited by chlorpromazine, trifluoperazine and imipramine, except no effect of imipramine on myeloperoxidase release. A C5a-elicited elevation of [$Ca^{2+}$]i in neutrophils was inhibited by chlopromazine, trifluoperazine, imipramine, staurosporine, genistein, EGTA, and verapamil but not affected by pertussis toxin. The intracellular $Ca^{2+}$ release in C5a-activated neutrophils was not affected by chlorpromazine and imipramine. Chlorpromazine and imipramine inhibited $Mn^{2+}$ influx by C5a-activated neutrophils. Thapsigargin-evoked $Ca^{2+}$ entry was inhibited by chlorpromazine, trifluoperazine, imipramine, genistein, EGTA and verapamil, while the effect of staurosporine was not detected. The results suggest that $Ca^{2+}$/calmodulin complex is involved in the activation process of neutrophils. The depressive action of calmodulin inhibitors on the elevation of cytosolic $Ca^{2+}$ level in C5a-activated neutrophils appears to be accomplished by inhibition of $Ca^{2+}$ influx from the extracellular medium.

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