• 제목/요약/키워드: GalN

검색결과 173건 처리시간 0.025초

Euonymus alatus 추출물의 실험적 간 손상 억제 (Protective effect of euonymus alatus extract on experimental liver injury in mice)

  • 신숙정;이병용;신동근;이정호
    • IMMUNE NETWORK
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    • 제1권3호
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    • pp.213-220
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    • 2001
  • Background: A previous study has shown that Euonymus alatus (EA) has an antidotic activities against inflammation, suggesting possibility that EA can exert this beneficial effects to liver injury by an initial protection against drug-induced hepatocyte demage. The present study was undertaken to evaluate the protective effect of EA-extract on experimentally induced hepatitis in ICR mice and to investigate some mechanisms responsible for its action. Methods: Water EA extract was used in this experiments. The mice received i.p. a dose of 700 mg/kg galactosamine (GalN) together with $5{\mu}g/kg$ of endotoxin (LPS), or received i.v. 12 mg/kg of concanavalin A (Con A). EA (4 mg/mouse) was administrated on day -2, -1 and 0 before induction of liver injury. Liver injury was assessed by measurement of serum alanin amino-transferase (SGPT) levels on 9 hr after GaIN.LPS, or 8 hr after con A administration. Results: Treatment with either GaIN or LPS alone did not cause hepatitis. However, simultaneous administration of GalN and LPS to mice resulted in LPS-dose dependent fulminant hepatitis. GaLN/LPS-induced liver injury was reduced when mice were given EA for 3 days before induction. This preventive effect of Ea was more prominent when EA was given by intraperitoneal route rather then by oral route. Pretreatment of EA or dexamethasone inhibited significantly $TNF{\alpha}$ production in GalL/LPS-injured mice. However, EA-treatment did not influence $TNF{\alpha}$-induced hepatitis in GalN-sensitized mice, suggesting that $TNF{\alpha}$ is likely to act as one of final mediators of endotoxin action and the protective effect of EA might be manifested chiefly by inhibition of endotoxin-induced $TNF{\alpha}$ production, not by blocking the $TNF{\alpha}$-action. Injection of Con A into mice evoked remarkable liver injury in a dose dependent fashion. This liver damage was reduced by EA-pretreatment. Dexamethasone significantly reduced both GalL/LPS-induced and Con A-induced liver damages, showing synergism with EA. However, indomethacin reduced only GalN/ LPS-induced hepatitis, not for Con A-induced hepatitis. Conclusion: These results led to the conclusion that EA may be able to contribute at least in part to prevent the drug-induced hepatotoxicity, and that its anti-hepatitis effects might be manifested directly by modulation of endogenous mediators, such as leukotriese D4, $TNF{\alpha}$ and free radical, and indirectly by regulation of immune mediated responses. Also these results suggested that EA could be developed as a potential antidotic agent.

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홍삼의 전처리에 의한 사염화탄소 및 갈락토사민 유발 간독성에 대한 보호효과 (Effects of Pretreated Korean Red Ginseng on Carbon Tetrachloride and Galactosamine-induced Hepatotoxicity in Rats)

  • 이정규;김나영;한용남;최종원
    • Journal of Ginseng Research
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    • 제27권1호
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    • pp.1-10
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    • 2003
  • In present study, we examined whether or not the pretreatment of Korean Red Ginseng (KRG) could protect hepatotoxicity induced by carbon tetrachloride (CCl$_4$) and D-galatosamine (GalN). For this study, we not only tested activity of various plasma enzymes (AST, ALT, SDH, LDH), which are used as indicators of liver disease, but also checked the change of liver components such as lipid, glutathione and cytochromes content, and several liver enzyme activity. Pretreatment of KRG for two weeks significantly reduced the elevated plasma enzyme activities induced by CCl$_4$ and GalN. Pretreatment of KRG also restored the hepatic enzymes, malonedialdehyde formation, and depletion of reduced glutathione content induced by CCl$_4$ and GalN to near normal level. However, ${\gamma}$-glutamylcysteine synthetase activity was lot affected by KRG. These results suggest that KRG shows the hepatoprotective effect by reducing lipid peroxidation, by reducing the activity of free radical generating enzymes, and by preserving the hepatic glutathione.

Development of a Reporter System Monitoring Regulated Intramembrane Proteolysis of the Transmembrane bZIP Transcription Factor ATF6α

  • Kim, Jin-Ik;Kaufman, Randal J.;Back, Sung Hoon;Moon, Ja-Young
    • Molecules and Cells
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    • 제42권11호
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    • pp.783-793
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    • 2019
  • When endoplasmic reticulum (ER) functions are perturbed, the ER induces several signaling pathways called unfolded protein response to reestablish ER homeostasis through three ER transmembrane proteins: inositol-requiring enzyme 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF6). Although it is important to measure the activity of ATF6 that can indicate the status of the ER, no specific cell-based reporter assay is currently available. Here, we report a new cell-based method for monitoring ER stress based on the cleavage of $ATF6{\alpha}$ by sequential actions of proteases at the Golgi apparatus during ER stress. A new expressing vector was constructed by using fusion gene of GAL4 DNA binding domain (GAL4DBD) and activation domain derived from herpes simplex virus VP16 protein (VP16AD) followed by a human $ATF6{\alpha}$ N-terminal deletion variant. During ER stress, the GAL4DBD-VP16AD(GV)-$hATF6{\alpha}$ deletion variant was cleaved to liberate active transcription activator encompassing GV-$hATF6{\alpha}$ fragment which could translocate into the nucleus. The translocated GV-$hATF6{\alpha}$ fragment strongly induced the expression of firefly luciferase in HeLa Luciferase Reporter cell line containing a stably integrated 5X GAL4 site-luciferase gene. The established double stable reporter cell line HLR-GV-$hATF6{\alpha}$(333) represents an innovative tool to investigate regulated intramembrane proteolysis of $ATF6{\alpha}$. It can substitute active pATF6(N) binding motif-based reporter cell lines.

Synergistic Effects of PectaSol-C Modified Citrus Pectin an Inhibitor of Galectin-3 and Paclitaxel on Apoptosis of Human SKOV-3 Ovarian Cancer Cells

  • Hossein, Ghamartaj;Keshavarz, Maryam;Ahmadi, Samira;Naderi, Nima
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권12호
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    • pp.7561-7568
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    • 2013
  • Galectin-3 (Gal-3) is a carbohydrate-binding protein which is thought to be involved in cancer progression but its contribution to epithelial ovarian cancer (EOC) remains unclear. The present study sought to determine the role of Gal-3 in chemoresistance of the human SKOV-3 ovarian cancer cell line to paclitaxel (PTX) using recombinant human Gal-3 (rhGal-3) and PectaSol-C modified citrus pectin (Pect-MCP) as a specific Gal-3 competitive inhibitor. Our results showed 41% increased cell proliferation, 36% decreased caspase-3 activity and 33.6% increased substrate-dependent adhesion in the presence of rhGal-3 compared to the control case (p<0.001). Treatment of cells with a non-effective dose of PTX (100nM) and 0.1% Pect-MCP in combination revealed synergistic cytotoxic effects with 75% reduced cell viability and subsequent 3.9-fold increase in caspase-3 activity. Moreover, there was 39% decrease in substrate-dependent adhesion compared to control (p<0.001). These results suggest that inhibition of Gal-3 could be a useful therapeutic tool for combination therapy of ovarian cancer.

Cloning and Expression of a Thermostable ${\alpha}$-Galactosidase from the Thermophilic Fungus Talaromyces emersonii in the Methylotrophic Yeast Pichia pastoris

  • Simila, Janika;Gernig, Anita;Murray, Patrick;Fernandes, Sara;Tuohy, Maria G.
    • Journal of Microbiology and Biotechnology
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    • 제20권12호
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    • pp.1653-1663
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    • 2010
  • The first gene (${\alpha}$-gal1) encoding an extracellular ${\alpha}$-Dgalactosidase from the thermophilic fungus Talaromyces emersonii was cloned and characterized. The ${\alpha}$-gal1 gene consisted of an open reading frame of 1,792 base pairs interrupted by six introns that encoded a mature protein of 452 amino acids, including a 24 amino acid secretory signal sequence. The translated protein had highest identity with other fungal ${\alpha}$-galactosidases belonging to glycosyl hydrolase family 27. The ${\alpha}$-gal1 gene was overexpressed as a secretory protein with an N-terminal histidine tag in the methylotrophic yeast Pichia pastoris. Recombinant ${\alpha}$-Gal1 was secreted into the culture medium as a monomeric glycoprotein with a maximal yield of 10.75 mg/l and purified to homogeneity using Hisbinding nickel-agarose affinity chromatography. The purified enzyme was maximally active at $70^{\circ}C$, pH 4.5, and lost no activity over 10 days at $50^{\circ}C$. ${\alpha}$-Gal1 followed Michaelis-Menten kinetics ($V_{max}\;of\;240.3{\mu}M/min/mg,\;K_m\;of\;0.294 mM$) and was inhibited competitively by galactose ($K_m{^{obs}}$ of 0.57 mM, $K_i$ of 2.77 mM). The recombinant T. emersonii ${\alpha}$-galactosidase displayed broad substrate preference, being active on both oligo- and polymeric substrates, yet had strict specificity for the ${\alpha}$-galactosidic linkage. Owing to its substrate preference and noteworthy stability, ${\alpha}$-Gal1 is of particular interest for possible biotechnological applications involving the processing of plant materials.

노화유도 쥐의 대동맥에서 L-arginine 투여와 규칙적인 운동의 효과: 염증인자와 혈관이완조절 인자의 변화 (Effects of L-Arginine Supplementation and Regular Exercise in D-Galactose Induced Aging Rat Aorta: Study on Inflammatory Factors, Vasodilation Regulatory Factors)

  • 이진;곽이섭;유영준;박석
    • 생명과학회지
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    • 제21권10호
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    • pp.1415-1421
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    • 2011
  • 이 연구는 L-arginine과 규칙적인 운동이 D-galctose (D-all)투여로 유발된 노화흰쥐의 대동맥에서 발현되는 NF-${\kappa}B$, TNF-a, iNOS, Cav-1, eNOS, Ang II의 변화양상을 관찰하는데 그 목적을 두고 있다. 노화유도 모델 쥐는 D-gal (50 mg/kg)를 숫컷 Strague-Dawley (SD)계 흰쥐의 복강에 1일 1회 총 12주간 투여하여 생산하였으며, 이 실험의 집단은 젊은 대조군(Y-con, n=8), 노화 대조군(A-con, n=8), 노화 운동군(A-Ex, n=8), 노화운동+아르기닌군(A-Ex+A, n=8), 노화 아르기닌군(A-A, n=8)의 5군으로 분류하여 실시하였다. L-arginine은 1일 150 mg/kg씩 총 12주간 경구투여 하였다. 운동방법은 트레이드운동으로 1일 60분씩 20 m/min 속도에서 훈련하였다. 분석결과 1) 유도된 노화군에서 NF-${\kappa}B$, TNF-a, iNOS, Cav-1, 그리고 Ang II 단백질의 발현은 젊은 대조군에 비해 유의하게 증가하였다. 그러나 규칙적인 운동과 L-아르기닌군에서 NF-${\kappa}B$, TNF-a, iNOS, Cav-1, 그리고 Ang II 단백질의 발현은 노화 대조군에 비해 유의하게 감소하였다. 2) 유도된 노화군에서의 eNOS 단백질 발현은 젊은 대조군에 비해 유의하게 감소하였다. 그러나 규칙적인 운동과 L-아르기닌군은 eNOS 단백질의 발현을 더욱 증가시킨 것으로 나타났다. 이상의 결과를 종합하면 12주간 L-아르기닌 투여와 규칙적인 운동 그리고 복합처치는 염증인자와 관련된 단백질인 NF-${\kappa}B$, TNF-a, iNOS 단백질들의 발현을 억제시켜 항염증효과를 보여주었으며, 혈관내피의 기능향상과 관련된 eNOS의 발현을 증가시키는데 긍정적인 역할을 수행할 것으로 기대된다.

GALOIS GROUP OF GENERALIZED INVERSE POLYNOMIAL MODULES

  • Park, Sang-Won;Jeong, Jin-Sun
    • East Asian mathematical journal
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    • 제24권2호
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    • pp.139-144
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    • 2008
  • Given an injective envelope E of a left R-module M, there is an associative Galois group Gal($\phi$). Let R be a left noetherian ring and E be an injective envelope of M, then there is an injective envelope E[$x^{-1}$] of an inverse polynomial module M[$x^{-1}$] as a left R[x]-module and we can define an associative Galois group Gal(${\phi}[x^{-1}]$). In this paper we extend the Galois group of inverse polynomial module and can get Gal(${\phi}[x^{-s}]$), where S is a submonoid of $\mathds{N}$ (the set of all natural numbers).

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RELATIONS OF IDEALS OF CERTAIN REAL ABELIAN FIELDS

  • Kim, Jae Moon
    • Korean Journal of Mathematics
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    • 제6권2호
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    • pp.221-229
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    • 1998
  • Let $k$ be a real abelian field and $k_{\infty}$ be its $\mathbb{Z}_p$-extension for an odd prime $p$. Let $A_n$ be the Sylow $p$-subgroup of the ideal class group of $k_n$, the $nth$ layer of the $\mathbb{Z}_p$-extension. By using the main conjecture of Iwasawa theory, we have the following: If $p$ does not divide $\prod_{{{\chi}{\in}\hat{\Delta}_k},{\chi}{\neq}1}B_{1,{\chi}{\omega}^{-1}$, then $A_n$ = {0} for all $n{\geq}0$, where ${\Delta}_k=Gal(k/\mathbb{Q})$ and ${\omega}$ is the Teichm$\ddot{u}$ller character for $p$. The converse of this statement does not hold in general. However, we have the following when $k$ is of prime conductor $q$: Let $q$ be an odd prime different from $p$. and let $k$ be a real subfield of $\mathbb{Q}({\zeta}_q)$. If $p{\mid}{\prod}_{{\chi}{\in}\hat{\Delta}_{k,p},{\chi}{\neq}1}B_{1,{\chi}{\omega}}-1$, then $A_n{\neq}\{0\}$ for all $n{\geq}1$, where ${\Delta}_{k,p}$ is the $Gal(k_{(p)}/\mathbb{Q})$ and $k_{(p)}$ is the decomposition field of $k$ for $p$.

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