• Title/Summary/Keyword: Tyrosine Kinase B

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Anti-Inflammatory Effects of Paeoniflorin Derivatives

  • Kim, Su-Ah;Jang, Eun-Seo;Lee, A-Yeon;Lee, Su-Jeong;Balcos, Marie-Carmel;Kim, June-Hyun
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.122-122
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    • 2018
  • We previously showed that the root extract of Paeonia lactiflora might have anti-inflammatory effects. Paeoniflorin (PF) has been identified as one of the main bioactive components of Paeonia lactiflora, however its role has been well characterized. In this study, we tested whether PF and its derivatives, which is removed the hydroxy group from PF, might have anti-inflammatory effects. In the Nitric Oxide assay, PF and Paeoniflorin's derivative (PFD) showed 55% and 56% more anti-inflammatory effect, compared to LPS control, respectively at 250ug/ml. To further confirm, we examined the effect of PF on tyrosine phosphorylation of Erk MAP Kinase. It is well established that tyrosine phosphorylation of Erk MAP Kinase is related to NF-kB mediated inflammation pathway. We therefore examined whther PF and PFD might regulate Erk activity. PF and PFD showed 35% and 22% less tyrosine phosphorylation compared to Paeonia lactiflora Red Charm extract control, respectively at 500ug/ml. Taken together, these results suggest that PF and PFD may play a role in anti-inflammatory effects in the root extract of Paeonia lactiflora. This study will provide the basis to develop a platform for the inflammation-mediated diseases therapeutics in the near future.

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Studies on the mechanism of Nitric oxide (NO) induction in the Peritoneal Macrophage by HERBA SAURUI (HS) (삼백초(三白草)가 복강(腹腔) 대식세포(大食細胞)로부터 Nitric Oxide(NO) 유리기전(遊離機轉)에 대한 연구(硏究))

  • Jeon, Gil-Hwan;Shin, Min-Kyo;Song, Ho-Joon
    • The Journal of Korean Medicine
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    • v.19 no.2
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    • pp.36-49
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    • 1998
  • HERBA SAURURI (HS) has been known to use antiinflammatory drug. To investigated the mechanism of HS-induced NO synthesis, I evaluated the ability of protein kinase C (PKC) inhibitors such as staurosporine (STSN) or polyymyxin B to block HS-induced effects. HS alone had only a small effect, whereas in combination with $rIFN-{\gamma}$, markedly increased NO synthesis in a dose dependent manner. STSN and polymyxin B decreased NO synthesis, which had been induced by $rIFN-{\gamma}$, plus HS. Furthermore, prolonged incubation of the cells with phorbol ester, which down-regulates PKC activity abolished synergistic cooperative effect of HS with $rIFN-{\gamma}$ on NO synthesis. STSN and Polymyxin B potently inhibited HS-induced $TNF-{\alpha}$ secretion by $rIFN-{\gamma}$ plus HS. However, $rIFN-{\gamma}$ plus $TNF-{\alpha}-induced$ NO synthesis was not blocked by STSN or polymyxin B. On the other hand, tyrosine kinase inhibitor, genistein, blocked the NO synthesis and $TNF-{\alpha}$ secretion by $rIFN-{\gamma}$ plus HS. In conlusion, the present results strongly suggest that the capacity of HS to increase NO synthesis from $rIFN-{\gamma}-primed$ macrophages is the result of HS-induced $TNF-{\alpha}$ secretion via the signal transduction pathway of PKC and tyrosine kinase.

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X-linked Agammaglobulinemia Assiociated with Bronchiectasis : A Case Report (기관지 확장증을 동반한 X연관 무감마글로불린혈증 1예)

  • Yu, Chang-Min;Koh, Won-Jung;Kim, Kyung Chan;Lee, Byoung-Hoon;Hwang, Jung Hye;Kang, Eun Hae;Suh, Gee Young;Chung, Man Pyo;Kim, Hojoong;Kwon, O Jung;Ki, Chang-Seok;Kim, Jong-Won
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.6
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    • pp.628-634
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    • 2003
  • Bronchiectasis is defined as an abnormal, irreversible dilatation of the bronchi, which may result from a number of possible causes, and the recognition of these causes may lead to a specific management strategy. Immunodeficiency is known as one of the conditions associated with bronchiectasis. X-linked agammaglobulinemia is a rare inheritable immunodeficiency disorder, caused by a differentiation block, leading almost to the complete absence of B lymphocytes and plasma cells. The affected protein is a cytoplasmic protein tyrosine kinase, Bruton's tyrosine kinase. The early detection and treatment with immunoglobulin replacement are most important for the management of recurrent infections and for reducing severe complications. We report a 20-year-old male patient, with X-linked agammaglobulinemia associated with bilateral bronchiectasis, carrying a missense mutation(R520P) in the BTK gene.

Role of Protein Kinases on NE-$_{\kappa}B$ Activation and Cell Death in Bovine Cerebral Endothelial Cells

  • Ahn, Young-Soo;Kim, Chul-Hoon;Kim, Joo-Hee
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.1
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    • pp.11-18
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    • 1999
  • Nuclear factor $_{\kappa}B\;(NF-_{\kappa}B)$ activation is modulated by various protein kinases. Activation of $NF-_{\kappa}B$ is known to be important in the regulation of cell viability. The present study investigated the effect of inhibitors of protein tyrosine kinase (PTK), protein kinase C (PKC) and protein kinase A (PKA) on $NF-_{\kappa}B$ activity and the viability of bovine cerebral endothelial cells (BCECs). In serum-deprivation-induced BCEC death, low doses of $TNF{\alpha}$ showed a protective effect. $TNF{\alpha}$ induced $NF-_{\kappa}B$ activation within 4 h in serum-deprivation. PTK inhibitors (herbimycin A and genistein) and PKC inhibitor (calphostin C) prevented $NF-_{\kappa}B$ activation stimulated by $TNF{\alpha}.$ Likewise, these inhibitors prevented the protective effect of $TNF{\alpha}.$ In contrast to $TNF{\alpha}-stimulated\;NF-_{\kappa}B$ activity, basal $NF-_{\kappa}B$ activity of BCECs in media containing serum was suppressed only by calphostin C, but not by herbimycin A. As well BCEC death was also induced only by calphostin C in serum-condition. H 89, a PKA inhibitor, did not affect the basal and $TNF{\alpha}-stimulated\;NF-_{\kappa}B$ activities and the protective effect of $TNF{\alpha}$ on cell death. These data suggest that modulation of $NF-_{\kappa}B$ activation could be a possible mechanism for regulating cell viability by protein kinases in BCECs.

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Isoflurane Induces Transient Anterograde Amnesia through Suppression of Brain-Derived Neurotrophic Factor in Hippocampus

  • Cho, Han-Jin;Sung, Yun-Hee;Lee, Seung-Hwan;Chung, Jun-Young;Kang, Jong-Man;Yi, Jae-Woo
    • Journal of Korean Neurosurgical Society
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    • v.53 no.3
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    • pp.139-144
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    • 2013
  • Objective : Transient anterograde amnesia is occasionally observed in a number of conditions, including migraine, focal ischemia, venous flow abnormalities, and after general anesthesia. The inhalation anesthetic, isoflurane, is known to induce transient anterograde amnesia. We examined the involvement of brain-derived neurotrophic factor (BDNF) and its receptor tyrosine kinase B (TrkB) in the underlying mechanisms of the isoflurane-induced transient anterograde amnesia. Methods : Adult male Sprague-Dawley rats were divided into three groups : the control group, the 10 minutes after recovery from isoflurane anesthesia group, and the 2 hours after recovery from isoflurane anesthesia group (n=8 in each group). The rats in the isoflurane-exposed groups were anesthetized with 1.2% isoflurane in 75% nitrous oxide and 25% oxygen for 2 hours in a Plexiglas anesthetizing chamber. Short-term memory was determined using the step-down avoidance task. BDNF and TrkB expressions in the hippocampus were evaluated by immunofluorescence staining and western blot analysis. Results : Latency in the step-down avoidance task was decreased 10 minutes after recovery from isoflurane anesthesia, whereas it recovered to the control level 2 hours after isoflurane anesthesia. The expressions of BDNF and TrkB in the hippocampus were decreased immediately after isoflurane anesthesia but were increased 2 hours after isoflurane anesthesia. Conclusion : In this study, isoflurane anesthesia induced transient anterograde amnesia, and the expressions of BDNF and TrkB in the hippocampus might be involved in the underlying mechanisms of this transient anterograde amnesia.

Type 3 muscarinic acetylcholine receptor stimulation is a determinant of endothelial barrier function and adherens junctions integrity: role of protein-tyrosine phosphatase 1B

  • Jiao, Zhou-Yang;Wu, Jing;Liu, Chao;Wen, Bing;Zhao, Wen-Zeng;Du, Xin-Ling
    • BMB Reports
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    • v.47 no.10
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    • pp.552-557
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    • 2014
  • The main purpose of this study was to investigate whether type 3 muscarinic acetylcholine receptor (M3R) dysfunction induced vascular hyperpermeability. Transwell system analysis showed that M3R inhibition by selective antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and small interfering RNA both increased endothelial permeability. Using coimmunoprecipitation and Western blot assay, we found that M3R inhibition increased VE-cadherin and ${\beta}$-catenin tyrosine phosphorylation without affecting their expression. Using PTP1B siRNA, we found that PTP1B was required for maintaining VE-cadherin and ${\beta}$-catenin protein dephosphorylation. In addition, 4-DAMP suppressed PTP1B activity by reducing cyclic adenosine monophosphate (cAMP), but not protein kinase $C{\alpha}$ ($PKC{\alpha}$). These data indicate that M3R preserves the endothelial barrier function through a mechanism potentially maintaining PTP1B activity, keeping the adherens junction proteins (AJPs) dephosphorylation.

HQSAR Study on Substituted 1H-Pyrazolo[3,4-b]pyridines Derivatives as FGFR Kinase Antagonists

  • Bhujbal, Swapnil P.;Balasubramanian, Pavithra K.;Keretsu, Seketoulie;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.10 no.2
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    • pp.85-94
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    • 2017
  • Fibroblast growth factor receptor (FGFR) belongs to the family of receptor tyrosine kinase. They play important roles in cell proliferation, differentiation, development, migration, survival, wound healing, haematopoiesis and tumorigenesis. FGFRs are reported to cause several types of cancers in humans which make it an important drug target. In the current study, HQSAR analysis was performed on a series of recently reported 1H-Pyrazolo [3,4-b]pyridine derivatives as FGFR antagonists. The model was developed with Atom (A) and bond (B) connection (C), chirality (Ch), hydrogen (H) and donor/acceptor (DA) parameters and with different set of atom counts to improve the model. A reasonable HQSAR model ($q^2=0.701$, SDEP=0.654, NOC=5, $r^2=0.926$, SEE=0.325, BHL=71) was generated which showed good predictive ability. The contribution map depicted the atom contribution in inhibitory effect. A contribution map for the most active compound (compound 24) indicated that hydrogen and nitrogen atoms in the side chains of ring B as well as hydrogen atoms in the side chain of ring C and the nitrogen atom in the ring D contributed positively to the activity in inhibitory effect whereas, the lowest active compound (compound 04) showed negative contribution to inhibitory effect. Thus results of our study can provide insights in the designing potent and selective FGFR kinase inhibitors.

Inhibition of IκB Kinase β (IKKβ) and Anti-diabetic Effect of SA51

  • Bhattarai, Bharat Raj;Kafle, Bhooshan;Hwang, Ji-Sun;Han, Inn-Oc;Cho, Hyeongjin
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2487-2490
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    • 2013
  • SA51, a medium potency inhibitor of protein tyrosine phosphatase 1B (PTP1B), was identified to be a potent inhibitor of $I{\kappa}B$ kinase ${\beta}$ ($IKK{\beta}$). Consistent with this, SA51 prevented lipopolysaccharide (LPS)-induced breakdown of $I{\kappa}B{\alpha}$ in macrophages. The effects of SA51 in mice were compared with those of structurally related compounds, SA18 and SA32, which were previously reported as inhibitors of both enzymes - less potent against $IKK{\beta}$ but more potent against PTP1B compared to SA51. SA51 improved glucose tolerance and lipid parameters in mice, consistent with the results reported for $IKK{\beta}^{+/-}$ mice. In contrast, SA18 and SA32 showed anti-obesity effects without anti-diabetic effects. Collectively, the effects of SA51 could be due largely to the inhibition of $IKK{\beta}$, whereas SA18 and SA32 may be more likely to inhibit PTP1B, consistent with their relative in vitro inhibitory effects.

Overexpression of GAP Causes the Delay of NGF-induced Neuronal Differentiation and the Inhibition of Tyrosine Phosphorylation of SNT in PC12 Cells

  • Yang, Sung-Il;Kaplan, David
    • BMB Reports
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    • v.28 no.4
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    • pp.316-322
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    • 1995
  • The GTPase activating protein (GAP) can function both as a negative regulator and an effector of $p21^{ras}$. Overexpression of GAP in NIH-3T3 cells has been shown to inhibit transformation by ms or src. To investigate the function of GAP in a differentiative system, we overexpressed this protein in the nerve growth factor (NGF)-responsive PC12 cell line. Two-fold overexpression of GAP caused a delay of several days in the onset of NGF- but not FGF-induced neuronal differentiation of PC12 cells. However, the NGF-induced activation or tyrosine phosphorylation of upstream (Trk, PLC-${\gamma}1$, SHC) and downstream (B-Raf and $p44^{mapk/erk1}$) components of $p21^{ras}$, signalling cascade was not altered by GAP overexpression. Therefore, the change of phenotype induced by GAP was probably not due to GAP functioning as a negative regulator of $p21^{ras}$. Rather, we found that NGF-induced tyrosine phosphorylation of SNT, a specific target of neurotrophin-induced tyrosine kinase activity, was inhibited by GAP overexpression. SNT is thought to function upstream or independent of $p21^{ras}$. Thus in PC12 cells, overexpressed GAP may control the rate of neuronal differentiation through a pathway involving SNT rather than the $p21^{ras}$ signalling pathway.

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