Eun Ju Yang

Kyungpook National University, Sangju, North Gyeongsang, South Korea

Are you Eun Ju Yang?

Claim your profile

Publications (28)63.73 Total impact

  • Article: Identification of active compounds from Aurantii Immatri Pericarpium attenuating brain injury in a rat model of ischemia-reperfusion.
    [show abstract] [hide abstract]
    ABSTRACT: Ischemic stroke is caused by brain injury due to prolonged ischemia by occlusion of cerebral arteries. In this study, we isolated active compounds from an ethanol extract of Aurantii Immatri Pericarpium (HY5356). We first showed by DNA fragmentation assay that HY5356 improved human hepatocellular carcinoma cells (HepG2) under hypoxic conditions by inhibiting apoptosis. When HY5356 was fractionated with dichloromethane (MC), ethyl acetate (EA) and n-butanol (BU), the MC fraction improved cell viability at the lowest concentration (100μg/ml). Intraperitoneal injection of HY5356 (200mg/kg) or the MC fraction (200mg/kg) to rats prior to occlusion attenuated brain injury significantly in a rat model of ischemia-reperfusion. Adopting cell viability under hypoxic conditions as an activity screening system, we isolated nobiletin and tangeretin as active compounds. The results suggest that intake of Aurantii Immatri Pericarpium containing nobiletin and tangeretin as active compounds might be beneficial for preventing ischemic stroke.
    Food Chemistry 05/2013; 138(1):663-70. · 3.65 Impact Factor
  • Article: Neuroprotective effects of neolignans isolated from Magnoliae Cortex against glutamate-induced apoptotic stimuli in HT22 cells.
    [show abstract] [hide abstract]
    ABSTRACT: In the course of screening for neuroprotective natural products, Magnoliae Cortex showed potent inhibition of hippocampal neuronal HT22 cell death. Obovatol, honokiol, and magnolol were isolated from the ethanolic extract of Magnoliae Cortex. Isolated compounds obovatol, honokiol, and magnolol were protective against 5 mM glutamate-induced cell death. When cells were stressed using glutamate, cell viability decreased to 16.98 ± 4.58% over the control (100.00 ± 10.15%). In contrast, 10 μM obovatol, 10 μM honokiol, and 50 μM magnolol increased cell viability to 91.80 ± 1.70%, 93.59 ± 1.93%, and 85.36±7.40%, respectively. The neuroprotective effects of obovatol and honokiol were attributable to the inhibition of intracellular reactive oxygen species production, followed by protection of the mitochondrial membrane potential (ΔΨm), recovery of Bcl-2 and Bid levels, inhibition of apoptosis-inducing factor expression, and phosphorylation of mitogen-activated protein kinases such as p38 kinases, extracellular signal-regulated kinases, and c-Jun N-terminal kinases. On the contrary, magnolol did not show any significant effect on the ΔΨm and apoptotic factors. Among three compounds, obovatol most strongly scavenged 2,2-diphenyl-1-picrylhydrazyl radicals and inhibited the elevation of intracellular reactive oxygen species levels in glutamate-stressed HT22 cells. These data suggest that obovatol and honokiol may have clinical applications for preventing neurodegenerative disorders.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 02/2013; · 2.99 Impact Factor
  • Article: Barrier protective effects of rosmarinic acid on HMGB1-induced inflammatory responses in vitro and in vivo.
    [show abstract] [hide abstract]
    ABSTRACT: High mobility group box 1 (HMGB1) protein is a crucial cytokine that mediates response to infection, injury, and inflammation. Rosmarinic acid (RA) is an important component of the leaves of Perilla frutescens and has neuroprotective, anti-microbial, anti-oxidant, and anti-cancer effects but little is known of its effects on HMGB1-mediated inflammatory response. Here, we investigated this issue by monitoring the effects of RA on the lipopolysaccharide (LPS) or cecal ligation and puncture (CLP)-mediated release of HMGB1 and HMGB1-mediated modulation of inflammatory responses. RA potently inhibited the release of HMGB1 and down-regulated HMGB1-dependent inflammatory responses in human endothelial cells. RA also inhibited HMGB1-mediated hyperpermeability and leukocyte migration in mice. Furthermore, RA reduced CLP-induced HMGB1 release and sepsis-related mortality. Given these results, RA should be viewed as a candidate therapeutic agent for the treatment of various inflammatory diseases via inhibition of the HMGB1 signaling pathway. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc.
    Journal of Cellular Physiology 10/2012; · 3.87 Impact Factor
  • Article: Anti-inflammatory Effects of Oleanolic Acid on LPS-Induced Inflammation In Vitro and In Vivo.
    [show abstract] [hide abstract]
    ABSTRACT: Oleanolic acid (OA) is a triterpenoid known for its anti-inflammatory and anti-cancer properties; however, the anti-inflammatory effects of OA on lipopolysaccharide (LPS)-mediated pro-inflammatory responses have not been studied. Here, we first investigated the possible anti-inflammatory effects of OA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) induced by LPS and the associated signaling pathways. We found that OA inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs), and adhesion/transendothelial migration of monocytes to HUVECs. OA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocyte migration in vivo. Further studies revealed that OA suppressed the production of tumor necrosis factor-α and activation of nuclear factor-κB by LPS. Collectively, these results suggest that OA has anti-inflammatory effects by inhibiting hyperpermeability, the expression of CAMs, and the adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapeutic agent for vascular inflammatory diseases.
    Inflammation 08/2012; · 1.75 Impact Factor
  • Article: Anticoagulant activities of oleanolic acid via inhibition of tissue factor expressions.
    [show abstract] [hide abstract]
    ABSTRACT: Oleanolic acid (OA), a triterpenoid known for its anti-inflammatory and anti-cancer properties, is commonly present in several medicinal plants but its anticoagulant activities have not been studied. Here, the anticoagulant properties of OA were determined by monitoring activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrin polymerization as well as cell-based thrombin and activated factor X (FXa) generation activities. Data showed OA prolonged aPTT and PT significantly and inhibited thrombin catalyzed fibrin polymerization. In addition, OA inhibited the activities of thrombin and FXa and inhibited the generation of thrombin or FXa in human endothelial cells. OA also inhibited TNF-α-induced tissue factor expression on human endothelial cells. In accordance with these anticoagulant activities, OA showed an anticoagulant effect in vivo. These results indicate that OA possesses antithrombotic activities and suggest that daily consumption of a herb containing OA may be preventing thrombosis in pathological states.
    BMB reports 07/2012; 45(7):390-5. · 1.72 Impact Factor
  • Article: The effects of benzene and toluene on leukotactin-1-induced migration of EoL-1 cells
    [show abstract] [hide abstract]
    ABSTRACT: Benzene and toluene are volatile organic compounds (VOCs) that are produced from various building materials and may lead to sick building syndrome. In addition, these materials exert cytotoxic and carcinogenic effects in immune cells. To understand the effects of VOCs on immunological regulation, we investigated the effects of VOCs on cell migration in response to CC chemokines such as leukotactin-1 (Lkn-1), monocyte chemoattractant protein-1 (MCP-1), eotaxin, MIP-1α and RANTES in human eosinophilic leukemia EoL-1 cells. VOCs exerted no cytotoxicity against EoL-1 cells at concentrations ranging from 0.1 μM to 50 μM. A chemotaxis assay was conducted to evaluate the cell movement. The assay revealed that benzene and toluene differentially increased the migration of EoL-1 cells in response to Lkn-1, but not MCP-1, eotaxin, MIP-1α or RANTES. The expression of CCR1 and CCR3 binding to Lkn-1 were not altered by benzene and toluene. Additionally, the increased cell migration due to benzene and toluene was inhibited by PD98059, SB202190 and SP600125. Benzene and toluene also induced the phosphorylation of ERK, p38 mitogen-activated protein kinase (p38 MAPK) and JNK in a time-dependent manner. Overall, benzene and toluene influenced Lkn-1-induced migration of human eosinophilic cells via activation of MAPKs. These results suggest that benzene and toluene play a role as risk factors in the regulation of immune response. Furthermore, these findings provide a role for VOCs in the immunological processes involved in indoor air pollution-induced diseases. KeywordsBenzene–Toluene–Eosinophils–Cell migration–Leukotactin-1
    Molecular and Cellular Toxicology 05/2012; 7(2):140-147. · 0.88 Impact Factor
  • Article: Inhibitory effects of Glycyrrhizae radix and its active component, isoliquiritigenin, on Aβ(25-35)-induced neurotoxicity in cultured rat cortical neurons.
    [show abstract] [hide abstract]
    ABSTRACT: This study investigated an ethanol extract from Glycyrrhizae radix (GR), the root of Glycyrrhiza uralensis (Leguminosae), for possible neuroprotective effects on neurotoxicity induced by amyloid β protein (Aβ) (25-35) in cultured rat cortical neurons. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 36 h induced neuronal apoptotic death. GR (10-50 μg/mL) prevented the Aβ (25-35)-induced neuronal apoptotic death, as assessed by a MTT assay and Hoechst 33342 staining. Furthermore, GR decreased the expression of Bax and active caspase-3, proapoptotic proteins, and increased Bcl-2, an antiapoptotic protein. GR also significantly inhibited Aβ (25-35)-induced elevation of the intracellular Ca(2+) concentration ([Ca(2+)](i)) and generation of reactive oxygen species (ROS) measured by fluorescent dyes. Isoliquiritigenin (1-20 μM), isolated from GR as an active component, inhibited Aβ (25-35)-induced neuronal apoptotic death, elevation of [Ca(2+)](i), ROS generation, and the change of apoptosis-associated proteins in cultured cortical neurons, suggesting that the neuroprotective effect of GR may be, at least partly, attributable to this compound. These results suggest that GR and isoliquiritigenin prevent Aβ (25-35)-induced neuronal apoptotic death by interfering with the increases of [Ca(2+)](i) and ROS, and GR may have a possible therapeutic role for preventing the progression of neurodegenerative disease such as Alzheimer's disease.
    Archives of Pharmacal Research 05/2012; 35(5):897-904. · 1.59 Impact Factor
  • Article: Isoliquiritigenin isolated from Glycyrrhiza uralensis protects neuronal cells against glutamate-induced mitochondrial dysfunction.
    [show abstract] [hide abstract]
    ABSTRACT: Glutamate-mediated excitotoxicity, which is associated with reactive oxygen species (ROS), is hypothesized to be a major contributor to pathological cell death in the mammalian central nervous system, and to be involved in many acute and chronic brain diseases. Here, we showed that isoliquiritigenin (ISL) isolated from Glycyrrhiza uralensis (Gu), one of the most frequently prescribed oriental herbal medicines, protected HT22 hippocampal neuronal cells from glutamate-induced oxidative stress. In addition, we clarified the molecular mechanisms by which it protects against glutamate-induced neuronal cell death. ISL reversed glutamate-induced ROS production and mitochondrial depolarization, as well as glutamate-induced changes in expression of the apoptotic regulators Bcl-2 and Bax. Pretreatment of HT22 cells with ISL suppresses the release of apoptosis-inducing factor from mitochondria into the cytosol. Taken together, our results suggest that ISL may protect against mitochondrial dysfunction by limiting glutamate-induced oxidative stress. In conclusion, our results demonstrated that ISL isolated from Gu has protective effects against glutamate-induced mitochondrial damage and hippocampal neuronal cell death. We expect ISL to be useful in the development of drugs to prevent or treat neurodegenerative diseases.
    Biochemical and Biophysical Research Communications 04/2012; 421(4):658-64. · 2.48 Impact Factor
  • Article: Fermentation enhances the in vitro antioxidative effect of onion (Allium cepa) via an increase in quercetin content.
    [show abstract] [hide abstract]
    ABSTRACT: Yellow onion (Allium cepa) extract showed enhanced antioxidative effects in 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC) and 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate and acetyl ester (CM-H(2)DCFDA) assay after being treated with a crude enzyme extract from soybean paste fungi, Aspergillus kawachii. HPLC analysis showed two increased and two decreased peaks after enzyme treatment. The decreased peaks were identified as quercetin-3,4'-di-O-β-d-glucoside (1) and quercetin-4'-O-β-d-glucoside (2), and peaks that increased were quercetin-3-O-β-d-glucoside (3) and quercetin (4), respectively. It was expected that 3 and 4 were originated from the glucosidic cleavage of their glucosides, 1 and 2. Among the increased compounds, only quercetin (4) showed strong antioxidative activity in the DPPH assay. In addition, the protective effect against glutamate-induced neurotoxicity in HT22 cells was increased when treated with 25 μg/ml of fermented onion. The enhanced neuroprotective effect was also originated from the increased quercetin content. As a consequence, fermentation raised the quercetin content in onion, and subsequently increased the antioxidative and neuroprotective activities.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 04/2012; 50(6):2042-8. · 2.99 Impact Factor
  • Article: Anti-inflammatory activities of oleanolic acid on HMGB1 activated HUVECs.
    [show abstract] [hide abstract]
    ABSTRACT: As a late mediator of inflammation, high mobility group box 1 (HMGB1) protein up-regulates pro-inflammatory cytokines in several inflammatory diseases. Further, high plasma levels of HMGB1 correlate with poor prognosis and increased mortality in patients with severe inflammation. Oleanolic acid (OA), a triterpenoid known for its anti-inflammatory and anti-cancer properties, is commonly present in several medicinal plants but the effects of OA on HMGB1-mediated pro-inflammatory responses of human endothelial cells is not well-studied. In this study, we investigated this question by monitoring the effect of OA on lipopolysaccharide (LPS)-mediated release of HMGB1 and the HMGB1-mediated modulation of inflammatory responses in human umbilical vein endothelial cells (HUVECs). OA potently inhibited the release of HMGB1 by HUVECs as well as down-regulated HMGB1-dependent adhesion and migration of the monocytic cell line THP-1 to activated HUVECs. OA also down-regulated the cell surface expression of the receptor of HMGB1, thereby inhibiting HMGB1-dependent pro-inflammatory responses by inhibiting activation of nuclear factor-κB (NF-κB) and production of tumor necrosis factor-α (TNF-α) by HMGB1. Given these results, OA showed anti-inflammatory activities and could be a candidate as a therapeutic agent for various inflammatory diseases through the inhibition of the HMGB1 signaling pathway.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 02/2012; 50(5):1288-94. · 2.99 Impact Factor
  • Article: Hydroquinone-induced apoptosis of human lymphocytes through caspase 9/3 pathway.
    Ji-Sook Lee, Eun Ju Yang, In Sik Kim
    [show abstract] [hide abstract]
    ABSTRACT: Hydroquinone (HQ) is a major benzene metabolite, which is produced after benzene biotransformation. In this study, we investigated the toxic effect of HQ on lymphocytes. HQ significantly induced the apoptosis of lymphocytes isolated from normal peripheral blood in both dose and time dependent courses. Volatile organic compounds such as benzene, phenol, formaldehyde, o- and p-xylene, and toluene have no effect on lymphocyte apoptosis. HQ induced the cleavage of procaspase 3 and procaspase 9, indicating activation of the pro-apoptotic enzymes. Supernatant was collected from normal lymphocytes after HQ treatment and it significantly induced the apoptosis of normal lymphocytes as compared to supernatant collected from normal lymphocytes without HQ treatment. HQ reduced the secretion of MCP-1, IL-6 and IL-8 increased by in vitro incubation, although benzene and phenol are not effective in cytokine production. HQ increased the intracellular ROS production of lymphocytes. Benzene and phenol also increased the ROS production. In summary, HQ has a cytotoxic effect on lymphocytes by apoptosis induction and the pro-apoptotic signaling is involved in caspase 9/3 pathway. Our results demonstrated that HQ induces apoptosis by activating caspases 9/3 pathway and that the toxic effect seems to be dependent on lymphocyte metabolism.
    Molecular Biology Reports 02/2012; 39(6):6737-43. · 2.93 Impact Factor
  • Article: Differential effect of CCL2 on constitutive neutrophil apoptosis between normal and asthmatic subjects.
    [show abstract] [hide abstract]
    ABSTRACT: In this study, we investigated the effects of CCL2 on constitutive apoptosis of normal and asthmatic neutrophils. CCL2 blocked the constitutive apoptosis of normal neutrophils through CCR2. CCL2 also induced elevation of the cytosolic Ca(2+) concentration but had no effect on normal neutrophil chemotaxis. Constitutive apoptosis, calcium influx, and cell migration of asthmatic neutrophils were not affected by CCL2 stimulation. Supernatant collected from CCL2-treated normal neutrophils inhibited the constitutive apoptosis of normal neutrophils. Anti-apoptotic signaling mediated by CCL2 was found to be associated with the PI3K/Akt/ERK/NF-κB cascade in normal neutrophils. Both the cleavage of procaspase 3 and procaspase 9 and the decrease of in Mcl-1 expression were delayed by CCL2 stimulation. Inhibition of NF-κB blocked constitutive apoptosis of neutrophils from asthmatic patients via inhibition of the cleavage of procaspase 3 and procaspase 9, in contrast to normal neutrophils. NF-κB was involved in CCL2-induced anti-apoptotic signaling in normal neutrophils, whereas NF-κB functioned as a basal pro-apoptotic factor in asthmatic neutrophils. A better understanding of the difference in the regulation of neutrophil apoptosis due to CCL2 between normal individuals and asthmatics will enable elucidation of the role of CC chemokine in neutrophils and a framework for understanding the pathogenesis of asthma.
    Journal of Cellular Physiology 08/2011; 227(6):2567-77. · 3.87 Impact Factor
  • Article: Anti-inflammatory effects of ethanolic extract from Lagerstroemia indica on airway inflammation in mice.
    [show abstract] [hide abstract]
    ABSTRACT: In the present study, we investigated whether the Lagerstroemia indica Linn (LI) extract has an anti-inflammatory effect on lung inflammation in ovalbumin-induced asthmatic mice. The LI extract was obtained from dried and powdered whole plants of LI using 80% ethanol. ELISA was performed to evaluate cytokine concentration. BALB/c mice were used as a mouse model of asthma after asthmatic induction by ovalbumin sensitization and inhalation. We examined the effects of the LI extract on leukocyte infiltration and mucus secretion using cell count and histological stain. The amount of cytokines, such as interleukin (IL)-2, IL-4, IL-5, IL-13, and TNF-α, was increased in Jurkat cells using the extract from house dust mites. Increased cytokine concentrations were inhibited by the LI extract. The LI extract suppressed the increased expression of IL-6 after treatment with mite extract of EoL-1 cells and THP-1 cells. In an in vivo experiment using asthmatic mice, the LI extract significantly inhibited leukocytosis and eosinophilia in bronchoalveolar lavage (BAL) fluid and lung tissue samples. The LI extract inhibited the increase in mucus secretion by goblet cells, blocked the production of reactive oxygen species in BAL fluid cells, and blocked the protein expression of IL-5 in BAL fluid. The concentration of ovalbumin-specific IgE in BAL fluid was weakly inhibited by the LI extract. These results suggest that the LI extract may be used as a valuable agent for treating allergic diseases such as asthma due to its anti-inflammatory property.
    Journal of ethnopharmacology 07/2011; 136(3):422-7. · 2.32 Impact Factor
  • Article: Suppression of ovalbumin-induced airway inflammatory responses in a mouse model of asthma by Mimosa pudica extract.
    [show abstract] [hide abstract]
    ABSTRACT: Asthma is an inflammatory airway disease. The pathogenic mechanisms of asthma include the infiltration of leukocytes and release of cytokines. Mimosa pudica (Mp) has been used traditionally for the treatment of insomnia, diarrhea and inflammatory diseases. Although Mp extract has various therapeutic properties, the effect of this extract on asthma has not yet been reported. This study investigated the suppressive effects of Mp extract on asthmatic responses both in vitro and in vivo. Mp extract was acquired from dried and powdered whole plants of M. pudica using 80% ethanol. BALB/c mice were used for the mouse model of asthma induced by ovalbumin. Mp extract significantly inhibited the HMC-1 cell migration induced by stem cell factor and blocked the release of monocyte chemotactic protein-1 (MCP-1) and interleukin-6 (IL-6) in EoL-1 cells. Leukocytosis, eosinophilia and mucus hypersecretion in asthmatic lung were significantly suppressed by Mp extract. The release of ovalbumin-specific IgE in bronchoalveolar lavage fluid and serum was also decreased. Mp extract treatment resulted in no liver cytotoxicity. The Mp extract has inhibitory properties on asthma and may be used as a potent therapeutic agent for allergic lung inflammation.
    Phytotherapy Research 01/2011; 25(1):59-66. · 2.09 Impact Factor
  • Article: The pro-apoptotic effect of hydroquinone in human neutrophils and eosinophils.
    [show abstract] [hide abstract]
    ABSTRACT: Hydroquinone (HQ) is a benzene metabolite that is involved in hematopoiesis via its accumulation into bone marrow. HQ also acts as a toxic agent that influences various immune responses. Both neutrophils and eosinophils function as important leukocytes in immunological regulation and immune diseases. In this study, we examined the toxic effects of HQ on the apoptosis of human neutrophils and eosinophils isolated from the blood of healthy donors. HQ markedly increased the apoptosis of neutrophils and eosinophils in a concentration- and a time-dependent manner. The pro-apoptotic effect is involved in activation of caspase 9 and caspase 3. Reactive oxygen species (ROS) production was enhanced after HQ treatment in a dose-dependent manner. In addition, HQ upregulated the release of IL-8 and MCP-1 from neutrophils and eosinophils, respectively. Taken together, the results of this study demonstrated that HQ strongly induces the apoptosis of neutrophils and eosinophils through the caspase 9/3-dependent pathway and the increased ROS production. HQ exerts a cytotoxic effect in human neutrophils and eosinophils and may impair the regulation of immune responses.
    Toxicology in Vitro 10/2010; 25(1):131-7. · 2.78 Impact Factor
  • Article: Suppressive effect of Petasites japonicus extract on ovalbumin-induced airway inflammation in an asthmatic mouse model.
    [show abstract] [hide abstract]
    ABSTRACT: Asthma is a disease marked by airway inflammation. Petasites japonicus (Pj) is known as an herb for treating asthma, oxidant stress and gastric ulcer in traditional Oriental medicine. In this study, the inhibitory effects of Pj extract on asthmatic responses were examined both in vitro and in vivo. The Pj extract was acquired from whole plants of Petasites japonicus using 80% ethanol. Cytotoxicity of the Pj extract on Jurkat cells and THP-1 cells was determined using MTT assay. ELISA was performed to determine the expression levels of cytokines, chemokines, and IgE. BALB/c mice were used for an OVA-induced asthmatic mouse model. Reactive oxygen species (ROS) production was stained with 2',7'-dichlorofluorescein diacetate and measured by fluorescence-activated cell sorting analysis. The effects of the Pj extract on leukocyte infiltration and mucus production were determined using periodic acid-Schiff staining as well as hematoxylin and eosin staining. The Pj extract inhibits the increased release of interleukin (IL)-2, IL-4, IL-5, IL-13, and TNF-α due to house dust mite in Jurkat cells and blocks IL-6 expression in THP-1 cells without cytotoxicity. In the asthmatic mouse model, the Pj extract inhibits eosinophil infiltration, mucus hypersecretion, and IL-5 level in bronchoalveolar lavage (BAL) fluid, and it has a scavenging effect on ROS production of cells in BAL fluid. The Pj extract has suppressive properties for the pathogenesis of airway inflammation and may be used as a potent agent for the treatment of asthma.
    Journal of ethnopharmacology 10/2010; 133(2):551-7. · 2.32 Impact Factor
  • Article: Syringin from stem bark of Fraxinus rhynchophylla protects Abeta(25-35)-induced toxicity in neuronal cells.
    [show abstract] [hide abstract]
    ABSTRACT: The medicinal herb Jinpi, derived from the dried stem barks of Fraxinus rhynchophylla belonging to Oleaceae is widely used as a variety of Korean folk remedies for anti-inflammatory, febricide, antidiarrhea, and antileukorrhea diseases. In the course of screening antidementia agents from natural products, F. rhynchophylla showed significant inhibitory activity toward Abeta(25-35)-induced neuronal cell death. An active principle was isolated and identified as syringin. When the neuroblastoma cells were exposed to 50 microM Abeta(25-35), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction rate (survival rate) decreased to 60.21 +/- 2.16% over control while syringin treated ones recovered cell viability up to 79.12 +/- 1.39% at 20 microM. In addition, 20 microM syringin almost completely removed Abeta(25-35)-induced reactive oxygen species. The neuroprotective effect of syringin seemed to be originated from the reduction of apoptosis since decrease in caspase-3 activity and expression, reduction in cleaved PARP, and DNA fragmentation were observed. These results suggest that F. rhynchophylla and syringin are expected to be useful for preventing Abeta(25-35)-induced neuronal cell damage.
    Archives of Pharmacal Research 04/2010; 33(4):531-8. · 1.59 Impact Factor
  • Article: The roles of MCP-1 and protein kinase C delta activation in human eosinophilic leukemia EoL-1 cells.
    Ji-Sook Lee, Eun Ju Yang, In Sik Kim
    [show abstract] [hide abstract]
    ABSTRACT: Idiopathic hypereosinophilc syndrome is a disorder associated with clonally eosinophilic proliferation. The importance of FIP1-like-1-platelet-derived growth factor receptor-alpha (FIP1L1-PDGFRA) in the pathogenesis and classification of HES has been recently reported. In this study, we investigated the contribution of monocyte chemoattractant protein-1 (MCP-1)/CCL2 to chemotactic activity and protein kinase C delta (PKC delta in the human eosinophilic leukemia cell line EoL-1. These cells express CCR2 protein among the CC chemokine receptors (CCR1-5). MCP-1 induces strong migration of EoL-1 cells and the chemotaxis signal in response to MCP-1 involves a G(i)/G(o) protein, phospholipase C (PLC), PKC delta, p38 MAPK and NF-kappaB. MCP-1 activates p38 MAPK via G(i)/G(o) protein, PLC and PKC delta cascade. MCP-1 also induces NF-kappaB translocation and the activation is inhibited by PKC delta activation. The increase in the basal expression and activity of PKC delta in EoL-1 cells, compared to normal eosinophils, inhibits apoptosis in EoL-1 cells. Anti-apoptotic mechanism of PKC delta is related to inhibition of caspase 3 and caspase 9, but not to FIP1L1-PDGFRA. PKC delta functions as an anti-apoptotic molecule, and is involved in EoL-1 cell movement stimulated by MCP-1. This study contributes to an understanding of MCP-1 in eosinophil biology and pathogenic mechanism of eosinophilic disorders.
    Cytokine 09/2009; 48(3):186-95. · 3.02 Impact Factor
  • Article: A novel (S)-(+)-decursin derivative, (S)-(+)-3-(3,4-dihydroxy-phenyl)-acrylic acid 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano[3,2-g]chromen-3-yl-ester, inhibits ovalbumin-induced lung inflammation in a mouse model of asthma.
    [show abstract] [hide abstract]
    ABSTRACT: (S)-(+)-Decursin is a coumarin compound present in herbal extracts that has various biological activities. (S)-(+)-Decursin attenuates pathophysiologic progression in cancer, bacterial infection and neuropathy. Asthma is an inflammatory disease associated with increased infiltration of leukocytes, especially eosinophils, and secretion of mucus into the airways. Although (S)-(+)-decursin, as well as (S)-(+)-decursin analogues, have various pharmacological properties, the effect of these compounds on asthma is not known. In the present study, we synthesized (S)-(+)-3-(3,4-dihydroxy-phenyl)-acrylic acid 2,2-dimethyl-8-oxo-3,4-dihydro-2H,8H-pyrano[3,2-g]chromen-3-yl-ester (compound 6, C6) from (S)-(+)-decursin and examined if C6 had any inhibitory effects on lung inflammation in a mouse model of ovalbumin-induced asthma. C6 significantly inhibited the leukocytosis (p < 0.01) and eosinophilia (p < 0.05) in bronchoalveolar lavage (BAL) fluid. Examination of lung tissues stained with hematoxylin and eosin and periodic acid Schiff reagents showed that C6 suppressed the increased infiltration of inflammatory cells and elevated mucus hypersecretion. Protein levels of interleukin (IL)-5 (p < 0.05) and eotaxin (p < 0.01) were significantly reduced in BAL fluid by C6. C6 also significantly reduced total and ovalbumin-specific immunoglobulin E (IgE) levels in BAL fluid (p < 0.01) as well as that in serum (p < 0.05). C6 may have pharmacological effects for asthma and may be a potent therapeutic agent for the treatment of allergic airway diseases.
    Biological & Pharmaceutical Bulletin 03/2009; 32(3):444-9. · 1.66 Impact Factor
  • Article: Inhibitory effects of Duchesnea chrysantha extract on ovalbumin-induced lung inflammation in a mouse model of asthma.
    [show abstract] [hide abstract]
    ABSTRACT: Duchesnea chrysantha (D. chrysantha) is a herb with anti-oxidative, anti-inflammatory and immune-enhancing properties. Asthma is an inflammatory disease of the lungs, and the hallmarks of the disease are increased inflammatory cell infiltration into the airways and poor respiratory function. Although there is the possibility that D. chrysantha may have an inhibitory effect on lung inflammation, the effects of D. chrysantha on asthma have not been fully investigated. In the present study, we investigated the anti-inflammatory activity of D. chrysantha extract (Dc extract) on lung inflammation in a murine model of ovalbumin-induced asthma. Dc extract was obtained from dried and powdered whole plants of D. chrysantha using 80% ethanol. BALB/c mice induced by ovalbumin sensitization and nebulization were used as a mouse model of asthma. RT-PCR and ELISA were performed to measure mRNA and protein expression of cytokines. We examined the effects of Dc extract on leukocyte infiltration and mucus secretion using periodic acid-Schiff staining as well as hematoxylin and eosin staining. Dc extract significantly inhibited leukocytosis and eosinophilia in the bronchoalveolar lavage (BAL) fluid (p<0.01). Dc extract significantly reduced the elevated infiltration of inflammatory cells (p<0.05) and inhibited the increased mucus secretion, despite the absence of significant value. Although Dc extract weakly inhibited the mRNA expression of IL-4, IL-5, IL-13, and eotaxin, it strongly inhibited the protein expression of IL-5 (p<0.05) and eotaxin (p<0.01) in BAL fluid. Ovalbumin-specific IgE levels in the serum and BAL fluid were blocked by Dc extract (p<0.05). These results suggest the possibility that Dc extract can exert suppressive effects on asthma and may provide evidence that Dc extract is a useful agent for the treatment of allergic airway disease.
    Journal of Ethnopharmacology 06/2008; 118(1):102-7. · 3.01 Impact Factor

Institutions

  • 2007–2013
    • Kyungpook National University
      • College of Agriculture and Life Sciences
      Sangju, North Gyeongsang, South Korea
    • Yonsei University
      • Department of Biomedical Laboratory Science
      Seoul, Seoul, South Korea
  • 2010–2012
    • Wonkwang University
      Iksan, North Jeolla, South Korea
  • 2007–2011
    • Eulji University
      Yŏng-dong, North Chungcheong, South Korea