• The Korean Journal of Physiology and Pharmacology
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• 제18권6호
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• pp.475-480
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• 2014

We investigated the question of whether cholesterol catabolite can influence expression of inflammatory cytokines via Toll-like receptors (TLR) in monocytic cells. Treatment of THP-1 monocytic cells with 27-hydroxycholesterol (27OHChol) resulted in induction of gene transcription of TLR6 and elevated level of cell surface TLR6. Addition of FSL-1, a TLR6 agonist, to 27OHChol-treated cells resulted in transcription of the $IL-1{\alpha}$ gene and enhanced secretion of the corresponding gene product. However, cholesterol did not affect TLR6 expression, and addition of FSL-1 to cholesterol-treated cells did not induce expression of $IL-1{\alpha}$. Using pharmacological inhibitors, we investigated molecular mechanisms underlying the expression of TLR6 and $IL-1{\alpha}$. Treatment with Akt inhibitor IV or U0126 resulted in significantly attenuated expression of TLR6 and $IL-1{\alpha}$ induced by 27OHChol and 27OHChol plus FSL-1, respectively. In addition, treatment with LY294002, SB202190, or SP600125 resulted in significantly attenuated secretion of $IL-1{\alpha}$. These results indicate that 27OHChol can induce inflammation by augmentation of TLR6-mediated production of $IL-1{\alpha}$ in monocytic cells via multiple signaling pathways.

• Journal of Veterinary Science
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• 제23권2호
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• pp.27.1-27.16
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• 2022

Background: The role of Toll-like receptors (TLRs) in a feline infectious peritonitis virus (FIPV) infection is not completely understood. Objectives: This study examined the expression of TLR3, TLR7, TLR9, tumor necrosis factor-alpha (TNF-α), interferon (IFN)-β, and interleukin (IL)-10 upon an FIPV infection in Crandell-Reese feline kidney (CRFK) cells and feline monocytes. Methods: CRFK cells and monocytes from feline coronavirus (FCoV)-seronegative cats and FCoV-seropositive cats were infected with type II FIPV-79-1146. At four, 12, and 24 hours post-infection (hpi), the expression of TLR3, TLR7, TLR9, TNF-α, IFN-β, and IL-10, and the viral load were measured using reverse transcription quantitative polymerase chain reaction. Viral protein production was confirmed using immunofluorescence. Results: FIPV-infected CRFK showed the upregulation of TLR9, TNF-α, and IFN-β expression between 4 and 24 hpi. Uninfected monocytes from FCoV-seropositive cats showed lower TLR3 and TLR9 expression but higher TLR7 expression compared to uninfected monocytes from FCoV-seronegative cats. FIPV-infected monocytes from FCoV-seropositive cats downregulated TLR7 and TNF-α expression between 4 and 24 hpi, and 4 and 12 hpi, respectively. IFN-β was upregulated early in FIPV-infected monocytes from FCoV-seropositive cats, with a significant difference observed at 12 hpi compared to FCoV-seronegative cats. The viral load in the CRFK and FIPV-infected monocytes in both cohorts of cats was similar over time.ConclusionTLR7 may be the key TLR involved in evading the innate response against inhibiting TNF-α production. Distinct TLR expression profiles between FCoV-seronegative and FCoV-seropositive cats were observed. The associated TLR that plays a role in the induction of IFN-β needs to be explored further.

• International Journal of Industrial Entomology and Biomaterials
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• 제42권1호
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• pp.1-6
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• 2021

Toll-like receptor (TLR) is responsible for the recognition of foreign protein. Accordingly, TLR is mainly expressed in the immune associated cells. When foreign protein such as silk sericin is considered for the graft, the response of TLR should be considered. TLR is not all or none responsive receptor. TLR can be activated differently by the intensity of the input. Silk sericin is easily fragmented. The protein conformation of silk sericin is different to the degumming method. TLR response to silk sericin may be different to the degumming method. Consequently, objective tailored extraction method should be investigated and developed.

• Clinical and Experimental Reproductive Medicine
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• 제50권1호
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• pp.44-52
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• 2023

Objective: The DNA integrity of spermatozoa that attach to fallopian tube (FT) cells is higher than spermatozoa that do not attach. FT epithelial cells can distinguish normal and abnormal sperm chromatin. This study investigated the effects of sperm with a high-DNA fragmentation index (DFI) from men with unexplained repeated implantation failure (RIF) on the Toll-like receptor (TLR) signaling pathway in human FT cells in vitro. Methods: Ten men with a RIF history and high-DFI and 10 healthy donors with low-DFI comprised the high-DFI (>30%) and control (<30%) groups, respectively. After fresh semen preparation, sperm were co-cultured with a human FT epithelial cell line (OE-E6/E7) for 24 hours. RNA was extracted from the cell line and the human innate and adaptive immune responses were tested using an RT2 profiler polymerase chain reaction (PCR) array. Results: The PCR array data showed significantly higher TLR-1, TLR-2, TLR-3, TLR-6, interleukin 1α (IL-1α), IL-1β, IL-6, IL-12, interferon α (IFN-α), IFN-β, tumor necrosis factor α (TNF-α), CXCL8, GM-CSF, G-CSF, CD14, ELK1, IRAK1, IRAK2, IRAK4, IRF1, IRF3, LY96, MAP2K3, MAP2K4, MAP3K7, MAP4K4, MAPK8, MAPK8IP3, MYD88, NFKB1, NFKB2, REL, TIRAP, and TRAF6 expression in the high-DFI group than in the control group. These factors are all involved in the TLR-MyD88 signaling pathway. Conclusion: The MyD88-dependent pathway through TLR-1, TLR-2, and TLR-6 activation may be one of the main inflammatory pathways activated by high-DFI sperm from men with RIF. Following activation of this pathway, epithelial cells produce inflammatory cytokines, resulting in neutrophil infiltration, activation, phagocytosis, neutrophil extracellular trap formation, and apoptosis.

• International Journal of Oral Biology
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• 제44권4호
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• pp.160-164
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• 2019

Porphyromonas gingivalis (Pg), Aggregatibacter actinomycetemcomitans (Aa), Tannerella forsythia (Tf), Prevotella intermedia (Pi), and Fusobacterium nucleatum (Fn) are major periodontal pathogens. Lipopolysaccharides (LPSs) from periodontal bacteria play an important role in periodontal pathogenesis by stimulating host cells to produce inflammatory cytokines. In this study, highly pure LPSs from the five major periodontopathogens were prepared, and their monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α)-inducing activities were compared in human umbilical vein endothelial cells (HUVECs) and THP-1 macrophagic cells, respectively. In HUVECs, LPSs from Aa and Fn were potent stimulators for MCP-1 induction; however, LPSs from Pg, Pi, and Tf were much weaker MCP-1 inducers. In THP-1 cells, LPSs from Pg, Aa, and Fn were relatively strong inducers of TNF-α, whereas LPSs from Pi and Tf produced little activity. The Toll-like receptor (TLR)2/TLR4 dependency of various LPSs was also determined by measuring NF-κB reporter activity in TLR2- or TLR4-expressing 293 cells. LPSs from Aa, Fn, and Tf stimulated only TLR4; however, LPSs from Pg and Pi stimulated both TLR2 and TLR4. These results suggest that LPSs from major periodontal bacteria differ considerably in their cell-stimulating activity.

• 한국가금학회지
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• 제50권4호
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• pp.283-291
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• 2023

지방산 결합 단백질(FABP)은 LCFA 수송, 지질 합성, 저장을 용이하게 하고, 염증을 포함한 다양한 경로에 영향을 미치는 신호 분자로 작용한다. 특히 FABP4는 혈관 및 심장관련 질환과 관련이 있으며, 대식세포 매개 염증 반응에서 역할을 한다. 이전의 연구들은 FABP4를 지방 생성을 위한 대표적인 바이오 마커일 뿐만 아니라, 면역 반응과도 상관관계가 있는 것으로 확인하였다. 본 연구는 톨-유사 수용체 3(TLR3) 활성화에 의한 닭 FABP4(chFABP4) 유전자의조절을 조사하고 chFABP4 전사 조절에 관여하는 신호 경로를 결정하는 것을 목표로 한다. 우리는 TLR3 자극 DF-1 세포에서 chFABP4의 전사 조절을 분석하였다. 결과는 TLR3 리간드인 폴리이노신-폴리시티딜산(PIC)으로 자극 시 chFABP4가 상향 조절되었음을 보여주었다. 특히 chFABP4 전사는 NF-κB 신호 경로에서 독립적으로 조절되었다. p38 억제에서 상향 조절되어 p38 신호 경로가 TLR3 활성화 DF-1 세포 내에서 chFABP4 전사를 억제할 수 있음을 보여주었다. 이와는 대조적으로, JNK 신호 경로 억제에서는 chFABP4 발현이 하향 조절되었으며, 이는 대식세포의 연구 결과와 일치하며, TLR3 활성화에 반응하여 DF-1 세포에서 chFABP4 전사를 위한 JNK 신호 전달 경로의 긍정적인 조절을 시사한다. MEK 경로 억제는 NF-κB 신호 전달과 유사한 조절을 초래하였다. 이러한 결과는 각 MAPK가 TLR3 활성화에 반응하여 DF-1 세포에서 chFABP4의 전사 조절에 차별적으로 기여함을 시사한다.

• 한국식품영양학회지
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• 제30권2호
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• pp.312-318
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• 2017

Aloe-emodin (AE) is the major bioactive component in aloe and known to exhibit anti-inflammatory activities. However, it has not been elucidated whether its anti-inflammatory potency can contribute to the elimination of obesity. The aim of the current study is to investigate the effect of AE on toll-like receptor 4 (TLR4) pathways in the presence of lipopolysaccharide (LPS) in 3T3-L1 adipocytes. 3T3-L1 adipocytes were treated with AE ($0-20{\mu}M$) for one hour, followed by LPS treatment for 30 min and then, adipokine mRNA expression levels were measured. Next, TLR4-related molecules were measured in LPS-stimulated 3T3-L1 adipocytes. AE significantly decreased the mRNA expression of the tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) in a dose-dependent manner. Moreover, AE suppressed TLR4 mRNA expression. Further study showed that AE could suppress the nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) and phosphorylation of extracellular receptor-activated kinase (pERK). The results of this study suggest that AE directly inhibits $TLR4/NF-{\kappa}B/ERK$ signaling pathways and decreases the inflammatory response in adipocytes.

• 대한의생명과학회지
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• 제27권3호
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• pp.177-181
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• 2021

Allergy is an immune response that appears in certain people, and reactions such as coughing, shortness of breath, and hives occur. The immune system plays an important role in homeostasis and host defense, and allergies cause hypersensitivity reactions when an imbalance of immunity occurs. Mutations in the TLR genes are associated with autoimmune conditions such as allergies and asthma. It has been reported that a locus in the TLR1-TLR6-TLR10 region may be associated with atopic sensitization or allergy. Therefore, the purpose of this study was to select an allergy patient group and a healthy control group to determine how the genetic mutation of TLR1 affects the onset of disease. This study was conducted in 709 patients and 5,025 control groups out of 10,956 patients with data from KARE and HEXA cohorts. As a result of logistic regression analysis of 6 SNPs selected from the TLR1 gene, only rs117033348 showed a statistically significant correlation (P = 0.002356). The influence of rs117033348 was examined using PolyPhen-2, and a significant result was shown. Therefore, it can be predicted that the G base in rs117033348 will have an influence on the human body. In addition, Geography of Genetic Variants browser was used to confirm the geographical distribution of allele frequencies for the TLR1 gene. Although it was found that there was a large racial difference in the prevalence of TLR1 SNP, it could be confirmed that the polymorphism of rs117033348 conducted in this study was only specific in East Asia when compared with each race.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1344-1354
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• 2022

Laryngeal cancer is one of the highest incidence, most prevalently diagnosed head and neck cancers, making it critically necessary to probe effective targets for laryngeal cancer treatment. Here, real-time quantitative reverse transcription PCR (qRT-PCR) and western blot analysis were used to detect gene expression levels in laryngeal cancer cell lines. Fluorescence in situ hybridization (FISH) and subcellular fractionation assays were used to detect the subcellular location. Functional assays encompassing Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), transwell and wound healing assays were performed to examine the effects of target genes on cell proliferation and migration in laryngeal cancer. The in vivo effects were proved by animal experiments. RNA-binding protein immunoprecipitation (RIP), RNA pulldown and luciferase reporter assays were used to investigate the underlying regulatory mechanisms. The results showed that KIF26B antisense RNA 1 (KIF26B-AS1) propels cell proliferation and migration in laryngeal cancer and regulates the toll-like receptor 4 (TLR4) signaling pathway. KIF26B-AS1 also recruits FUS to stabilize TLR4 mRNA, consequently activating the TLR4 signaling pathway. Furthermore, KIF26B-AS1 plays an oncogenic role in laryngeal cancer via upregulating TLR4 expression as well as the FUS/TLR4 pathway axis, findings which offer novel insight for targeted therapies in the treatment of laryngeal cancer patients.

• Clinical and Experimental Pediatrics
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• 제52권6호
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• pp.667-673
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• 2009

목 적 : TLR2는 숙주의 항결핵 방어면역의 중요한 역할을 하는 것으로 알려져 있다. 본 연구는 BCG 접종 후 발생한 화농성 림프절염 환자 단핵구에서 TLR2의 발현과 TLR2 리간드 자극에 의한 $TNF-{\alpha}$와 IL-6의 생성을 조사하여 화농성 림프절염 발병과 TLR2의 연관성을 알아보고자 하였다. 방 법 : BCG 접종 후 발생한 화농성 림프절염 환자 16명과 건강 대조군 10명의 말초 혈액에서 단핵구를 분리하고, TLR2 리간드인 Pam3CSK4로 자극한 후 유세포분석과 역전사중합효소반응을 이용하여 TLR2의 발현을 측정하였고, 자극 후 $TNF-{\alpha}$와 IL-6의 생성을 측정하여 TLR2의 발현 정도를 간접적으로 조사하였다. 결 과 : BCG 접종 후 발생한 화농성 림프절염 환자 단핵구의 TLR2 발현 정도($3.39{\pm}1.2%$)는 대조군($4.64{\pm}2.6%$)에 비하여 유의하게 감소하였고, 단핵구 자극에 의한 $TNF-{\alpha}$와 IL-6의 생성도 대조군($TNF-{\alpha}$, $1,098.5{\pm}94.3pg/mL$; IL-6, $6,696.3{\pm}544.3pg/mL$)에 비하여 환자군($TNF-{\alpha}$, $775.5{\pm}60.8pg/mL$; IL-6, $4,645.8{\pm}583.9pg/mL$)에서 유의하게 감소하였다. 그리고 자극 시간에 따른 TLR2 발현 정도와 $TNF-{\alpha}$와 IL-6의 생성 증가가 유사한 양상을 나타내었다. 결 론 : 본 연구의 결과에서 BCG 접종 후 발생한 화농성 림프절염 환자군 단핵구의 TLR2 발현 감소가 연관되어 있고, M. bovis BCG의 리간드 인식에 TLR2가 관여함을 추정할 수 있다.