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Extract from Prunus mume Sieb. et Zucc. Fruit Prevents LPS-induced Homotypic Aggregation of Monocytic THP-1 Cells via Suppression of Nitric Oxide Production and NF-κB Activation (매실 추출물의 산화질소 생성과 NF-κB 활성 조절을 통한 LPS유도성 THP-1 세포 동형성 응집의 억제 효과)

  • Lee, Hye-Rim;Park, Youngsook;Kim, Hyun Jeong;Lee, Aram;Choi, Jihea;Pyee, Jaeho;Park, Heonyong;Kim, Jongmin
    • Journal of Life Science
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    • v.25 no.7
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    • pp.801-809
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    • 2015
  • Homotypic cell adhesion (homotypic aggregation) in activated monocytes plays a central role in physiological and pathological processes including inflammatory responses, differentiation and migration. The extract of the Prunus mume Sieb. et Zucc. fruit (Maesil) has potential benefits to human health; such as anti-viral, anti-microbial, and anti-cancer activities. Indeed, Maesil extract may modulate inflammatory responses via interference with homotypic aggregation in monocytes. In the present study, the molecular mechanisms underpinning the therapeutic efficacy of Maesil extract in inflammatory diseases were investigated. It was found that Maesil extract inhibited homotypic aggregation in lipopolysaccharide (LPS)-activated monocytes. This was mediated by reduction of nitric oxide (NO) production, partly via inhibition of inducible nitric oxide synthase (iNOS) expression in LPS-activated THP-1 cells. It was confirmed that NO inhibition is a key mechanism in Maesil induced blockade of monocyte aggregation through identification of reversal of this inhibitory effect by the NO-producing agent S-nitroso-N-acetyl penicillamine (SNAP). In addition, Maesil extract significantly attenuated LPS-induced IκB-α phosphorylation and NF-κB translocation into the nucleus. In conclusion, Maesil extract exerts anti-inflammatory effects via inhibition of homotypic aggregation of LPS-activated monocytes through mechanisms involving the suppression of NO production and NF-κB activity, suggesting Maesil extract as a potential therapeutic candidate for the prevention and treatment of chronic inflammatory diseases.

Anti-Inflammatory Effects of Picrasma Quassioides (D.DON) BENN Leaves Extracts (소태나무 잎 추출물의 항염증 효과)

  • Jung, Yeon Seop;Eun, Cheong Su;Jung, Young Tae;Kim, Hyun Jeong;Yu, Mi Hee
    • Journal of Life Science
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    • v.23 no.5
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    • pp.629-636
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    • 2013
  • This study was performed to evaluate the anti-inflammatory and antioxidant activities of methanol extract from the leaves of Picrasma quassioides BENNET (PLME). The antioxidant effects of PLME were measured based on polyphenol and flavonoid contents. PLME was found to have $367.52{\mu}g/mg$ and $46.61{\mu}g/mg$ high polyphenol and flavonoid contents. Cell viability was determined by MTT assay. The production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) was measured by Griess assay and enzyme-linked immunosorbent assay (ELISA). In order to effectively anti-inflammatory agents, we examined the inhibitory effects on the production of lipopolysaccharide (LPS)-induced NO and $PGE_2$ in RAW 264.7 cells. PLME significantly decreased the production of NO and $PGE_2$ in a dose-dependent manner, and also reduced the expression of iNOS, a COX-2 protein. In addition, PLME reduced the NF-${\kappa}B$, $I{\kappa}B$ phosphorylation in RAW 264.7 cells upon stimulation with LPS (100 ng/ml) for 24 h. These results provide evidence for the anti-inflammatory and antioxidant effects of Picrasma quassioides leaves.

An Investigation of Glyceollin I's Inhibitory Effect on The Mammalian Adenylyl (글리세올린 I의 아데니닐 고리화 효소 활성 억제 효능과 결합 부위 비교 분석)

  • Kim, Dong-Chan;Kim, Nam Doo;Kim, Sung In;Jang, Chul-Soo;Kweon, Chang Oh;Kim, Byung Weon;Ryu, Jae-Ki;Kim, Hyun-Kyung;Lee, Suk Jun;Lee, Seungho;Kim, Dongjin
    • Journal of Life Science
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    • v.23 no.5
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    • pp.609-615
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    • 2013
  • Glyceollin I has gained attention as a useful therapy for various dermatological diseases. However, the binding property of glyceollin I to the mammalian adenylyl cyclase (hereafter mAC), a critical target enzyme for the down-regulation of skin melanogenesis, has not been fully explored. To clarify the action mechanism between glyceollin I and mAC, we first investigated the molecular docking property of glyceollin I to mAC and compared with that of SQ22,536, a well-known mAC inhibitor, to mAC. Glyceollin I showed superiority by forming three hydrogen bonds with Asp 1018, Trp 1020, and Asn 1025, which exist in the catalytic site of mAC. However, SQ22,536 formed only two hydrogen bonds with Asp 1018 and Asn 1025. Secondly, we confirmed that glyceollin I effectively inhibits the formation of forskolin-induced cAMP and the phosphorylation of PKA from a cell-based assay. Long term treatment with glyceollin I had little effect on the cell viability. The findings of the present study also suggest that glyceollin I may be extended to be used as an effective inhibitor of hyperpigmentation.

Hsp70 and IKKγ Synergistically Suppress the Activation of NF-κB (Hsp70와 IKKγ에 의한 NF-κB 활성억제의 상승효과)

  • Kim, Mi Jeong;Kim, Ka Hye;Kim, Moon Jeong;Kim, Jin Ik;Choi, Hye Jung;Moon, Ja Young;Joo, Woo Hong;Kim, Dong Wan
    • Journal of Life Science
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    • v.26 no.9
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    • pp.991-998
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    • 2016
  • NF-κB acts as a critical transcription factor for the survival of cells via the induction of antiapoptotic genes. Constitutive activation of NF-κB in many types of solid tumors suggests that the inhibition of NF-κB might prevent or inhibit tumorigenesis. Although a number of studies demonstrated that Hsp70 regulated NF-κB activity, the exact mechanism is not clear. This study investigated the functional relationship of Hsp70 and IKKγ in the regulation of NF-κB activation using expression plasmids of components of the IKK complex. Wild-type and deletion mutants of IKKγ were expressed together with Hsp70, and the combined regulatory effect of Hsp70 and IKKγ on NF-κB activation was assayed. Hsp70 suppressed the activation of NF-κB in a reporter plasmid assay. Hsp70 also suppressed the phosphorylation and degradation of IκBα. The suppressive effect of Hsp70 on NF-κB activation was synergistically elevated by IKKγ. The N-terminal IKKβ binding site, C-terminal leucine zipper, and zinc finger domains of IKKγ were not necessary for the suppressive effect. Furthermore, Hsp70 and IKKγ synergistically suppressed the induction of COX-2 expression by lipopolysaccharides in RAW264.7 cells. These results suggest that overexpression of Hsp70 and IKKγ may be a strategic method for inhibition of NF-κB and related diseases.

Suppression of Helicobacter pylori-induced Angiogenesis by a Gastric Proton Pump Inhibitor (Proton Pump Inhibitor에 의한 Helicobacter pylori의 혈관형성 억제효과)

  • Jin, Sung-Ho;Lee, Hwa-Young;Kim, Dong-Kyu;Cho, Yong-Kwan;Hahm, Ki-Baik;Han, Sang-Uk
    • Journal of Gastric Cancer
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    • v.5 no.3 s.19
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    • pp.191-199
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    • 2005
  • Background: Though infections of Helicobacter pylori (H. pylori) are closely associated with activation of host angiogenesis, the underlying mechanisms, as well as the strategy for its prevention, have not been identified. Here, we investigated a causal role of H. pylori infection in angiogenesis of gastric mucosa and a potent inhibitory effect of a gastric proton pump inhibitor (PPI) on the gastropathy. Materials and Methods: A comparative analysis of CD 34 expression in tissues obtained from 20 H. pylori-associated gastritis and 18 H. pylori-negative gastritis patients was performed. Expression of $HIF-1{\alpha}$ and VEGF were tested by using RT-PCR. To evaluate the direct effect of H. pylori infection on differentiation of endothelial HUVEC cells, we carried out an in vitro angiogenesis assay. Results: H. pyfori-associated gastritis tissues showed significantly higher density of $CD34^+$ blood vessels than did H. pylori-negative gastritis tissues, and the levels were well correlated with expressions of $HIF-1{\alpha}$. Conditioned media from H. pylori-infected gastric mucosal cells stimulated a tubular formation of HUVEC cells. We also found a significant inhibitory effect of PPI, an agent frequently used for H. pylori eradication, on H. pylori-induced angiogenesis. This drug effectively inhibited the phosphorylation of MAP kinase ERK1/2, which is a principal signal for H. pylori-induced angiogenesis. Conclusion: The fact that PPls can down-regulate H. pylori-induced angiogenesis suggest that anti-angiogenic treatment using PPI may be a preventive approach for H. pylori-associated carcinogenesis.

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Anti-diabetic effect and mechanism of Korean red ginseng extract in C57BL/KsJ db/db mice

  • Yuan, Hai-Dan;Shin, Eun-Jung;Chung, Sung-Hyun
    • Proceedings of the Ginseng society Conference
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    • 2007.12a
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    • pp.57-58
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    • 2007
  • Purpose: Ginseng is a well-known medical plant used in traditional Oriental medicine. Korean red ginseng (KRG) has been known to have potent biological activities such as radical scavenging, vasodilating, anti-tumor and anti-diabetic activities. However, the mechanism of the beneficial effects of KRG on diabetes is yet to be elucidated. The present study was designed to investigate the anti-diabetic effect and mechanism of KRG extract in C57BL/KsJ db/db mice. Methods: The db/db mice were randomly divided into six groups: diabetic control group (DC), red ginseng extract low dose group (RGL, 100 mg/kg), red ginseng extract high dose group (RGH, 200 mg/kg), metformin group (MET, 300 mg/kg), glipizide group (GPZ, 15 mg/kg) and pioglitazone group (PIO, 30 mg/kg), and treated with drugs once per day for 10 weeks. During the experiment, body weight and blood glucose levels were measured once every week. At the end of treatment, we measured Hemoglobin A1c (HbA1c), blood glucose, insulin, triglyceride (TG), adiponectin, leptin, non-esterified fatty acid (NEFA). Morphological analyses of liver, pancreas and white adipose tissue were done by histological observation through hematoxylin-eosin staining. Pancreatic islet insulin and glucagon levels were detected by double-immunofluorescence staining. To elucidate an action of mechanism of KRG, DNA microarray analyses were performed, and western blot and RT-PCR were conducted for validation. Results: Compared to the DC group mice, body weight gain of PIO treated group mice showed 15.2% increase, but the other group mice did not showed significant differences. Compared to the DC group, fasting blood glucose levels were decreased by 19.8% in RGL, 18.3% in RGH, 67.7% in MET, 52.3% in GPZ, 56.9% in PIO-treated group. With decreased plasma glucose levels, the insulin resistance index of the RGL-treated group was reduced by 27.7% compared to the DC group. Insulin resistance values for positive drugs were all markedly decreased by 80.8%, 41.1% and 68.9%, compared to that of DC group. HbA1c levels in RGL, RGH, MET, GPZ and PIO-treated groups were also decreased by 11.0%, 6.4%, 18.9%, 16.1% and 27.9% compared to that of DC group, and these figure revealed a similar trend shown in plasma glucose levels. Plasma TG and NEFA levels were decreased by 18.8% and 16.8%, respectively, and plasma adiponectin and leptin levels were increased by 20.6% and 12.1%, respectively, in the RGL-treated group compared to those in DC group. Histological analysis of the liver of mice treated with KRG revealed a significantly decreased number of lipid droplets compared to the DC group. The control mice exhibited definitive loss and degeneration of islet, whereas mice treated with KRG preserved islet architecture. Compared to the DC group mice, KRG resulted in significant reduction of adipocytes. From the pancreatic islet double-immunofluorescence staining, we observed KRG has increased insulin production, but decreased glucagon production. KRG treatment resulted in stimulation of AMP-activated protein kinase (AMPK) phosphorylation in the db/db mice liver. To elucidate mechanism of action of KRG extract, microarray analysis was conducted in the liver tissue of mice treated with KRG extract, and results suggest that red ginseng affects on hepatic expression of genes responsible for glycolysis, gluconeogenesis and fatty acid oxidation. In summary, multiple administration of KRG showed the hypoglycemic activity and improved glucose tolerance. In addition, KRG increased glucose utilization and improved insulin sensitivity through inhibition of lipogenesis and activation of fatty acid $\beta$-oxidation in the liver tissue. In view of our present data, we may suggest that KRG could provide a solid basis for the development of new anti-diabetic drug.

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Assessment of Abnormality in Skeletal Muscle Metabolism in Patients with Chronic Lung Desease by $^{31}P$ Magnetic Resonance Spectroscopy ($^{31}P$ 자기 공명분석법을 이용한 만성 폐질환 환자에서의 골격근대사 이상에 관한 연구)

  • Cho, Won-Kyoung;Kim, Dong-Soon;Lim, Tae-Hwan;Lim, Chae-Man;Lee, Sang-De;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.583-591
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    • 1997
  • The functional derangement of skeletal muscles which may be attributed to chronic hypoxia has been accepted as a possible mechanism of exercise impairment in patients with chronic obstructive pulmonary disease (COPD). The metabolic changes in skeletal muscle in patients with COPD are characterized by impaired oxidative phosphorylation, early activation of anaerobic glycolysis and excessive lactate and hydrogen ion production with exercise. But the cause of exercise limitation in patients with chronic lung disease without hypoxia has not been known. In order to evaluate the change in the skeletal muscle metabolism as a possible cause of the exercise limitation in chronic lung disease patients without hypoxia, we compared the muscular metabolic data of seven male patients which had been derived from noninvasive $^{31}P$ magnetic resonance spectroscopy(MRS) with those of five age-matched normal male control persons. $^{31}P$ MRS was studied during the sustained isometric contraction of the dominant forearm flexor muscles up to the exhaustion state and the recovery period. Maximal voluntary contraction(MVC) force of the muscle was measured before the isometric exercise, and the 30% of MVC force was constantly loaded to each patient during the isometric exercise. There were no differences of intracellular pH (pHi) and inorganic phosphate/phosphocreatine(Pi/PCr) at baseline, exhaustion state and recovery period between two groups. But pHi during the exercise was lower in patients group than the control group (p < 0.05). Pi/PCr during the exercise did not show significant difference between two groups. These results suggest that the exercise limitation in chronic lung disease patients without hypoxia also could be attributed to the abnormalities in the skeletal muscle metabolism.

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Diagnostic Efficacy of FDG-PET in Solitary Pulmonary Nodule (고립성폐결절에서 FDG-PET의 진단적 유용성)

  • Kim, Woo-Jin;Yim, Jae-Joon;Yoo, Chul-Gyu;Kim, Young-Whan;Shim, Young-Soo;Han, Sung-Koo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.6
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    • pp.1263-1270
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    • 1997
  • Background : Differentiation of malignity and benignity is crucial for management of solitary pulmonary nodule(SPN). Clinical parameters such as patient's age, nodule size, smoking history, doubling time, typical calcification in X-ray and CT findings have been reported as helpful in this purpose. However, in most cases, these parameters are not conclusive. Glucose metabolism is increased in cancer tissues including lung cancer tissues. After uptake of 2-[F-18]-fluoro-2-deoxy-D-glucose(FDG), the glucose analogue, by cancer cell, FDG is trapped in the cell without further metabolism after phosphorylation. Thus, hypermetabolic focus in FDG-positron emission tomography (PET) imaging suggest malignancy. We evaluated the diagnostic efficacy of FDG-PET imaging in distinguishing malignant and benign SPN. Methods : We evaluated 28 patients with SPN from Jan. 1995 to Jan. 1997. CT scan of chest and whole-body FDG-PET imaging were performed in all patients. Histologic diagnosis was confirmed by transthoracic fine needle aspiration and biopsy, bronchoscopic biopsy and open thoracotomy. Results : Of the 28 SPN's, 22 nodules were malignant and 6 nodules were benign. FDG-PET imaging diagnosed all malignant nodules correctly as positive, and diagnosed 4 of 6 benign nodules correctly as negative. One tuberculous granuloma and one aspergilloma showed hypennetabolic focus and were diagnosed falsely positve with FDG-PET imaging. In the diagnosis of SPN with FDG-PET, sensitivity and specificity were 100% and 66.7%, positive predictive value and negative predictive value were 92% and 100%. Conclusion : FDG-PET imaging is highly useful noninvasive diagnostic tool in distinguishing between malignant SPN and benign SPN.

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Anti-inflammatory effect of barley leaf ethanol extract in LPS-stimulated RAW264.7 macrophage (LPS로 자극한 RAW264.7 대식세포에서 보리순 에탄올 추출물의 항염증 효과)

  • Kim, Mee-Kyung;Kim, Dae-Yong
    • Food Science and Preservation
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    • v.22 no.5
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    • pp.735-743
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    • 2015
  • This study investigated the anti-inflammatory activity of barley leaf extract in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and hairless mice. Pre-treatment with barley leaf extract significantly inhibited the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-II (COX-II) in a dose-dependent manner in LPS-stimulated RAW264.7 cells. Barley leaf extract also significantly inhibited the secretion of inflammatory cytokines, such as tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and interleukin-6 (IL-6). Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-${\kappa}B$) were strongly suppressed by barley leaf extract in LPS-stimulated cells. In hairless mice, barley extract significantly decreased the pathological phenotypes of contact dermatitis, such as erythema, edema, and scabs. These results indicate that barley leaf extract has an anti-inflammatory effect and therefore a possible role in the treatment of inflammatory diseases or in functional cosmetics.

Apoptotic Cell Death by Pectenotoxin-2 in p53-Deficient Human Hepatocellular Carcinoma Cells (종양억제유전자 p53 결손 인체간암세포에서 Pectenotoxin-2에 의한 Apoptosis 유도)

  • Shin, Dong-Yeok;Kim, Gi-Young;Choi, Byung-Tae;Kang, Ho-Sung;Jung, Jee-H.;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1447-1451
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    • 2007
  • Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.