• 제목/요약/키워드: toll-like receptor 3 signaling

검색결과 91건 처리시간 0.026초

Protective effect of ultrasonication-processed ginseng berry extract on the D-galactosamine/lipopolysaccharide-induced liver injury model in rats

  • Nam, Yoonjin;Bae, Jinhyung;Jeong, Ji Hoon;Ko, Sung Kwon;Sohn, Uy Dong
    • Journal of Ginseng Research
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    • 제42권4호
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    • pp.540-548
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    • 2018
  • Background: Acute hepatic failure is a life-threatening critical condition associated with rapid deterioration of liver function and liver transplantation. Several studies have shown that Panax ginseng Mayer has antidiabetic and hepatoprotective effects. However, the hepatoprotective effect of ginseng berry is still unveiled. In this study, we evaluated the hepatoprotective effects of ultrasonication-processed ginseng berry extract (UGBE) on acute hepatic failure model in rats. Methods: Ginseng berry extract (GBE) was ultrasonically processed. The GBE, silymarin, and UGBE were orally administered to male Sprague-Dawley rats for 4 wk. Twenty-four h after the last administration, rats were challenged with D-galactosamine (D-GalN)/lipopolysaccharide (LPS). Results: After ultrasonication, the component ratio of ginsenosides Rg2, Rg3, Rh1, Rh4, Rk1, Rk3, and F4 in GBE had been elevated. Administration of UGBE significantly increased the survival rate of D-GalN/LPS-challenged rats. Pretreatment with UGBE significantly decreased serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels in D-GalN/LPS-challenged rats in a dose-dependent manner. The levels of enzymatic markers for oxidative stress (superoxide dismutase, glutathione peroxidase, catalase, and glutathione) were increased by UGBE treatment in a dose-dependent manner. Tumor necrosis factor alphalevel, inducible nitric oxide synthase activities, and nitric oxide productions were reduced by UGBE treatment. In addition, hemeoxygenase-1 levels in liver were also significantly increased in the UGBE-treated group. The protein expression of toll-like receptor 4 was decreased by UGBE administration. Hematoxylin and eosin staining results also supported the results of this study showing normal appearance of liver histopathology in the UGBE-treated group. Conclusion: UGBE showed a great hepatoprotective effect on D-GalN/LPS-challenged rats via the toll-like receptor 4 signaling pathway.

Molecular Characterization and Expression Analysis of Nucleoporin 210 (Nup210) in Chicken

  • Ndimukaga, Marc;Bigirwa, Godfrey;Lee, Seokhyun;Lee, Raham;Oh, Jae-Don
    • 한국가금학회지
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    • 제46권3호
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    • pp.185-191
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    • 2019
  • Nucleoporin 210(Nup210)는 근육 및 신경세포의 분화, 자기 면역 질환, 말초 T세포 항상성 등 여러 생리작용에 관여한다. 닭의 Nup210 유전자는 닭 신장조직에서 칼슘 의존성 차별 발현 유전자로 발굴되었으며, 닭의 대사 이상 질환과 Nup210의 관련 연구를 위해 Nup210 유전자의 분자유전학적 특성을 구명하고, 톨-유사수용체 3(Toll-like receptor 3(TLR3)) 자극에 의한 전사 조절을 연구하였다. 닭의 여러 조직과 배아 섬유아세포주인 DF-1 세포에서 Nup210 유전자의 전사 수준을 조사한 결과, 폐와 비장 조직에서 가장 높게 발현되었으며, Nup210의 발현은 TLR3 신호자극에 의해 증가함을 확인하였다. 또한 닭 Nup210 유전자가 코딩하는 단백질의 구조는 조류, 어류, 포유류를 포함한 여러 종과 매우 보존적이나 진화적으로 다른 포유류보다는 오리와 가장 가깝다고 추정되었다. 본 연구의 결과를 통해 닭 Nup210이 TLR3 신호시스템에 관여함을 확인하였고, 추가연구를 통해 바이러스 침입에 대한 닭 면역 메커니즘을 구명할 필요가 있다고 사료된다.

RAW 264.7 세포에서 담배잎산말의 TLR4/MAPKs/NF-κB 신호전달체계 조절을 통한 항염증 효과 (Desmarestia tabacoides Ameliorates Lipopolysaccharide-induced Inflammatory Responses via Attenuated TLR4/MAPKs/NF-κB Signaling Cascade in RAW264.7 Cells)

  • 윤현서;안현;박충무
    • 생명과학회지
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    • 제33권6호
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    • pp.463-470
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    • 2023
  • Desmarestia tabacoides Okamura는 전 세계적으로 널리 분포하는 갈조류 중 하나이다. 몇몇 산말류의 항종양, 멜라닌 생성 억제 및 광보호 활성에 대한 연구는 있었으나 D. tabacoides Okamura의 항염증 기전에 대해서는 보고되지 않아 본 연구에서는 LPS (lipopolysaccharide)로 자극된 RAW 264.7 세포에서 D. tabacoides Okamura 에탄올 추출물(DTEE)의 항염증 기전을 inducible nitric oxide synthase (iNOS)와 cyclooxygenase (COX)-2의 발현 및 이들의 상위신호전달물질인 nuclear factor (NF)-κB, mitogen-activated protein kinase (MAPK) 그리고 phosphoinositide-3-kinase (PI3K)/Akt의 인산화 조절 정도를 통해 분석하였다. DTEE의 처리는 세포 독성 없이 LPS로 유도된 NO와 prostaglandin (PG) E2의 생성과 이들의 생성 효소인 iNOS 및 COX-2의 발현을 유의하게 억제하였다. 그리고 LPS에 의해 활성화된 NF-κB 및 상위 신호 전달 물질인 extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK) 및 p38은 DTEE 처리에 의해 유의적으로 억제되었다. DTEE의 처리는 RAW 264.7 세포에서 LPS에 의해 활성화되는 adaptor molecule인 Toll-like receptor (TLR) 4 및 myeloid differentiation primary response (MyD) 88 또한 유의적으로 억제하였다. 이 결과를 통해 DTEE는 LPS에 의해 유도된 TLR4와 NF-κB 및 MAPK의 활성을 억제함으로써 염증 매개인자의 발현을 조절하였고, 이는 DTEE가 염증을 완화할 수 있는 기능성 식품의 소재로써 유용하게 사용될 수 있음을 시사한다.

Suppression of the TRIF-dependent signaling pathway of toll-like receptors by (E)-isopropyl 4-oxo-4-(2-oxopyrrolidin-1-yl)-2-butenoate

  • Park, Se-Jeong;Park, Hye-Jeong;Kim, Soo-Jung;Shin, Hwa-Jeong;Min, In-Soon;Koh, Kwang-Oh;Kim, Dae-Young;Youn, Hyung-Sun
    • BMB Reports
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    • 제44권7호
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    • pp.468-472
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    • 2011
  • Toll-like receptors (TLRs) are pattern recognition receptors that recognize molecular structures derived from microbes and initiate innate immunity. TLRs have two downstream signaling pathways, the MyD88- and TRIF-dependent pathways. Dysregulated activation of TLRs is closely linked to increased risk of many chronic diseases. Previously, we synthesized fumaryl pyrrolidinone, (E)-isopropyl 4-oxo-4-(2-oxopyrrolidin-1-yl)-2-butenoate (IPOP), which contains a fumaric acid isopropyl ester and pyrrolidinone, and demonstrated that it inhibits the activation of nuclear factor kappa B by inhibiting the MyD88-dependent pathway of TLRs. However, the effect of IPOP on the TRIF-dependent pathway remains unknown. Here, we report the effect of IPOP on signal transduction via the TRIF-dependent pathway of TLRs. IPOP inhibited lipopolysaccharide- or polyinosinic-polycytidylic acidinduced interferon regulatory factor 3 activation, as well as interferon-inducible genes such as interferon inducible protein-10. These results suggest that IPOP can modulate the TRIF-dependent signaling pathway of TLRs, leading to decreased inflammatory gene expression.

6-Shogaol의 Toll-like receptor 2, 3, 4 agonists에 의해서 유도된 cyclooxygenase-2 발현 억제 (Suppression of the Expression of Cyclooxygenase-2 Induced by Toll-like Receptor 2, 3, and 4 Agonists by 6-Shogaol)

  • 김점지;안상일;이전수;윤새미;이미영;윤형선
    • 한국식품과학회지
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    • 제40권3호
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    • pp.332-336
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    • 2008
  • 선천성 면역은 병원성균의 침입에 대항하기 위한 숙주의 최초 방어체계라 할 수 있다. 이러한 선천성 면역반응은 병원균들이 가지고 있는 독특한 구조를 인식하는 TLRs에 의해서 조절되어 진다고 알려져 있다. 숙주에 침입한 여러 병원성균들이 TLRs를 자극하며 이렇게 자극된 신호들은 아래로 전달되어 전사요소 $NF-{\kappa}B$의 활성화를 유도하고 결국 COX-2와 같은 염증 유발인자를 유도하여 암이나 질병을 유발하게 된다. 우리는 이번 연구를 통하여 생강 추출물중의 하나인 6-shogaol이 어떻게 $NF-{\kappa}B$ 활성화나 COX-2 발현을 조절하여 항염증 효과를 가지고 있는지를 알아보았다. 6-shogaol은 TLR2, TLR3, TLR4 agonists에 의해서 유도된 $NF-{\kappa}B$ 활성화와 COX-2 발현을 억제하였다. 이러한 결과는6-shogaol이 여러 병원균들로부터 유도되는 염증반응이나 만성적인 질병들을 조절할 수 있다는 중요한 결과를 보여주는 것이라 할 수 있다.

Nucleotide-Binding Domain and Leucine-Rich Repeat Containing Receptor (NLR) and its Signaling Pathway

  • Park, Sangwook;Gwon, Sun-Yeong;Rhee, Ki-Jong
    • 대한의생명과학회지
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    • 제19권3호
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    • pp.173-179
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    • 2013
  • Since the identification and characterization of toll-like receptors (TLR) in Drosophila, numerous scientific studies have examined the role of TLRs in host innate immunity. Recent studies have suggested a convergence of the nuclear factor kappa B (NF-${\kappa}B$) signaling and cytokine production regulated by the cytosolic elicitor known as NLRs (nucleotide-binding domain and leucine-rich repeat containing domain receptors) as a key modulator in inflammatory diseases. Among the NLRs, NOD1 and NOD2 have been intensively investigated for its role in inflammatory bowel disease (IBD). On the other hand, NLRs such as NLRP3, NLRP1, and NLRC4 (also known as IPAF) have been identified to form the inflammasome to activate downstream signaling molecules in response to pathogenic microbes. There is evidence to suggest that substantial crosstalk exists for the TLR and NLR signaling pathway in response to pathogen associated molecular pattern (PAMP). However, the substrate and the mechanistic role of NLRs are largely unknown in innate immune response. Understanding the signaling mechanisms by which NLRs recognize PAMP and other danger signals will shed light on elucidating the pathogenesis of various human inflammatory diseases such as IBD.

Cell Death and Stress Signaling in Glycogen Storage Disease Type I

  • Kim, So Youn;Bae, Yun Soo
    • Molecules and Cells
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    • 제28권3호
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    • pp.139-148
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    • 2009
  • Cell death has been traditionally classified in apoptosis and necrosis. Apoptosis, known as programmed cell death, is an active form of cell death mechanism that is tightly regulated by multiple cellular signaling pathways and requires ATP for its appropriate process. Apoptotic death plays essential roles for successful development and maintenance of normal cellular homeostasis in mammalian. In contrast to apoptosis, necrosis is classically considered as a passive cell death process that occurs rather by accident in disastrous conditions, is not required for energy and eventually induces inflammation. Regardless of different characteristics between apoptosis and necrosis, it has been well defined that both are responsible for a wide range of human diseases. Glycogen storage disease type I (GSD-I) is a kind of human genetic disorders and is caused by the deficiency of a microsomal protein, glucose-6-phosphatase-${\alpha}$ ($G6Pase-{\alpha}$) or glucose-6-phosphate transporter (G6PT) responsible for glucose homeostasis, leading to GSD-Ia or GSD-Ib, respectively. This review summarizes cell deaths in GSD-I and mostly focuses on current knowledge of the neutrophil apoptosis in GSD-Ib based upon ER stress and redox signaling.

Regulation of toll-like receptors expression in muscle cells by exercise-induced stress

  • Park, Jeong-Woong;Kim, Kyung-Hwan;Choi, Joong-Kook;Park, Tae Sub;Song, Ki-Duk;Cho, Byung-Wook
    • Animal Bioscience
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    • 제34권10호
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    • pp.1590-1599
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    • 2021
  • Objective: This study investigates the expression patterns of toll-like receptors (TLRs) and intracellular mediators in horse muscle cells after exercise, and the relationship between TLRS expression in stressed horse muscle cells and immune cell migration toward them. Methods: The expression patterns of the TLRs (TLR2, TLR4, and TLR8) and downstream signaling pathway-related genes (myeloid differentiation primary response 88 [MYD88]; activating transcription factor 3 [ATF3]) are examined in horse tissues, and horse peripheral blood mononuclear cells (PBMCs), polymorphonuclear cells (PMNs) and muscles in response to exercise, using the quantitative reverse transcription-polymerase chain reaction (qPCR). Expressions of chemokine receptor genes, i.e., C-X-C motif chemokine receptor 2 (CXCR2) and C-C motif chemokine receptor 5 (CCR5), are studied in PBMCs and PMNs. A horse muscle cell line is developed by transfecting SV-T antigen into fetal muscle cells, followed by examination of muscle-specific genes. Horse muscle cells are treated with stressors, i.e., cortisol, hydrogen peroxide (H2O2), and heat, to mimic stress conditions in vitro, and the expression of TLR4 and TLR8 are examined in stressed muscle cells, in addition to migration activity of PBMCs toward stressed muscle cells. Results: The qPCR revealed that TLR4 message was expressed in cerebrum, cerebellum, thymus, lung, liver, kidney, and muscle, whereas TLR8 expressed in thymus, lung, and kidney, while TLR2 expressed in thymus, lung, and kidney. Expressions of TLRs, i.e., TLR4 and TLR8, and mediators, i.e., MYD88 and ATF3, were upregulated in muscle, PBMCs and PMNs in response to exercise. Expressions of CXCR2 and CCR5 were also upregulated in PBMCs and PMNs after exercise. In the muscle cell line, TLR4 and TLR8 expressions were upregulated when cells were treated with stressors such as cortisol, H2O2, and heat. Migration of PBMCs toward stressed muscle cells was increased by exercise and oxidative stresses, and combinations of these. Treatment with methylsulfonylmethane (MSM), an antioxidant on stressed muscle cells, reduced migration of PBMCs toward stressed muscle cells. Conclusion: In this study, we have successfully cultured horse skeletal muscle cells, isolated horse PBMCs, and established an in vitro system for studying stress-related gene expressions and function. Expression of TLR4, TLR8, CXCR2, and CCR5 in horse muscle cells was higher in response to stressors such as cortisol, H2O2, and heat, or combinations of these. In addition, migration of PBMCs toward muscle cells was increased when muscle cells were under stress, but inhibition of reactive oxygen species by MSM modulated migratory activity of PBMCs to stressed muscle cells. Further study is necessary to investigate the biological function(s) of the TLR gene family in horse muscle cells.

Inflammasomes: Molecular Regulation and Implications for Metabolic and Cognitive Diseases

  • Choi, Alexander J.S.;Ryter, Stefan W.
    • Molecules and Cells
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    • 제37권6호
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    • pp.441-448
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    • 2014
  • Inflammasomes are specialized signaling platforms critical for the regulation of innate immune and inflammatory responses. Various NLR family members (i.e., NLRP1, NLRP3, and IPAF) as well as the PYHIN family member AIM2 can form inflammasome complexes. These multiprotein complexes activate inflammatory caspases (i.e., caspase-1) which in turn catalyze the maturation of select pro-inflammatory cytokines, including interleukin (IL)-$1{\beta}$ and IL-18. Activation of the NLRP3 inflammasome typically requires two initiating signals. Toll-like receptor (TLR) and NOD-like receptor (NLR) agonists activate the transcription of pro-inflammatory cytokine genes through an NF-${\kappa}B$-dependent priming signal. Following exposure to extracellular ATP, stimulation of the P2X purinoreceptor-7 ($P2X_7R$), which results in $K^+$ efflux, is required as a second signal for NLRP3 inflammasome formation. Alternative models for NLRP3 activation involve lysosomal destabilization and phagocytic NADPH oxidase and /or mitochondria-dependent reactive oxygen species (ROS) production. In this review we examine regulatory mechanisms that activate the NLRP3 inflammasome pathway. Furthermore, we discuss the potential roles of NLRP3 in metabolic and cognitive diseases, including obesity, type 2 diabetes mellitus, Alzheimer's disease, and major depressive disorder. Novel therapeutics involving inflammasome activation may result in possible clinical applications in the near future.

Functional Gene Analysis to Identify Potential Markers Induced by Benzene in Two Different Cell Lines, HepG2 and HL-60

  • Kim, Youn-Jung;Song, Mi-Kyung;Sarma, Sailendra Nath;Choi, Han-Saem;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • 제4권3호
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    • pp.183-191
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    • 2008
  • Volatile organic compounds (VOCs) are common constituents of cleaning and degreasing agents, paints, pesticides, personal care products, gasoline and solvents. And VOCs are evaporated at room temperature and most of them exhibit acute and chronic toxicity to human. Benzene is the most widely used prototypical VOC and the toxic mechanisms of them are still unclear. The multi-step process of toxic mechanism can be more fully understood by characterizing gene expression changes induced in cells by toxicants. In this study, DNA microarray was used to monitor the expression levels of genes in HepG2 cells and HL-60 cells exposed to the benzene on IC20 and IC50 dose respectively. In the clustering analysis of gene expression profiles, although clusters of HepG2 and HL-60 cells by benzene were divided differently, expression pattern of many genes observed similarly. We identified 916 up-regulated genes and 1,144 down-regulated genes in HepG2 cells and also 1,002 up-regulated genes and 919 down-regulated genes in HL-60 cells. The gene ontology analysis on genes expressed by benzene in HepG2 and HL-60 cells, respectively, was performed. Thus, we found some principal pathways, such as, focal adhesion, gap junction and signaling pathway in HepG2 cells and toll-like receptor signaling pathway, MAPK signaling pathway, p53 signaling pathway and neuroactive ligand-receptor interaction in HL-60 cells. And we also found 16 up-regulated and 14 down-regulated commonly expressed total 30 genes that belong in the same biological process like inflammatory response, cell cycle arrest, cell migration, transmission of nerve impulse and cell motility in two cell lines. In conclusion, we suggest that this study is meaningful because these genes regarded as strong potential biomarkers of benzene independent of cell type.