Meat and fiber intake and interaction with pattern recognition receptors (TLR1, TLR2, TLR4, and TLR10) in relation to colorectal cancer in a Danish prospective, case-cohort study.

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Kopp, Tine Iskov; Vogel, Ulla; Tjonneland, Anne; Andersen, Vibeke

2018-03-01

Meat and dietary fiber are associated with increased and decreased risk of colorectal cancer (CRC), respectively. Toll-like receptors (TLRs) regulate the intestinal immune response in a complex interplay between the mucosal epithelium and the microbiota and may therefore be important modulators of diet-induced CRC together with other inflammatory mediators. Our aim was to investigate the association between functional TLR polymorphisms and risk of CRC and the interaction with dietary factors. Additionally, interactions with previously studied polymorphisms in IL10, IL1B, PTGS2, and NFKB1 were assessed in order to examine possible biological pathways in meat-induced CRC. A nested case-cohort study of 897 CRC cases and 1689 randomly selected participants from the Danish prospective "Diet, Cancer and Health" study encompassing 57,053 persons was performed using Cox proportional hazard models and the likelihood ratio test. We found associations between polymorphisms in TLR2 (P = 0.018) and TLR4 (P = 0.044) and risk of CRC per se, interactions between intake of red and processed meat (10 g/d) and polymorphisms in TLR1 (P-interaction = 0.032) and TLR10 (P-interaction = 0.026 and 0.036), and intake of cereals (50 g/d) and TLR4 (P-interaction = 0.044) in relation to risk of CRC. Intake of red and processed meat also interacted with combinations of polymorphisms in TLR1 and TLR10 and polymorphisms in NFKB1, IL10, IL1B, and PTGS2 (P-interaction; TLR1/rs4833095 × PTGS2/rs20417 = 0.021, TLR10/rs11096955 × IL10/rs3024505 = 0.047, TLR10/rs11096955 × PTGS2/rs20417 = 0.017, TLR10/rs4129009 × NFKB1/rs28362491 = 0.027, TLR10/rs4129009 × IL1B/rs4848306 = 0.020, TLR10/rs4129009 × IL1B/rs1143623 = 0.021, TLR10/rs4129009 × PTGS2/rs20417 = 0.027), whereas intake of dietary fiber (10 g/d) interacted with combinations of polymorphisms in TLR4, IL10, and PTGS2 (P-interaction; TLR4/rs1554973 × IL10/rs3024505 = 0.0012, TLR4/rs1554973 × PTGS2/rs20417 = 0.0041, TLR4/rs1554973 × PTGS

Should a Toll-like receptor 4 (TLR-4 agonist or antagonist be designed to treat cancer? TLR-4: its expression and effects in the ten most common cancers

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Mai CW

2013-11-01

Full Text Available Chun Wai Mai, Yew Beng Kang, Mallikarjuna Rao PichikaDepartment of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, Kuala Lumpur, MalaysiaAbstract: Toll-like receptor 4 (TLR-4 is well known for its host innate immunity. Despite the fact that TLR-4 activation confers antitumor responses; emerging evidence suggests that TLR-4 is associated with tumor development and progression. It is now clear that overactivation of TLR-4, through various immune mediators, may cause immune response dysfunction, resulting in tumorigenesis. Different cancers could have different extents of TLR-4 involvement during tumorigenesis or tumor progression. In this review, we focus on infection- and inflammation-related TLR-4 activation in noncancer and cancer cells, as well as on the current evidence about the role of TLR-4 in ten of the most common cancers, viz, head and neck cancer, lung cancer, gastrointestinal cancer, liver cancer, pancreatic cancer, skin cancer, breast cancer, ovarian cancer, cervical cancer, and prostate cancer.Keywords: drug design, cancer treatment, myeloid differentiation factor 2, MD-2, tumor progression, pathogen-associated molecular patterns, PAMPs

Coxiella burnetii lipopolysaccharide blocks p38α-MAPK activation through the disruption of TLR-2 and TLR-4 association

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Filippo eConti

2015-01-01

Full Text Available To survive in macrophages, Coxiella burnetii hijacks the activation pathway of macrophages. Recently, we have demonstrated that C. burnetii, via its lipopolysaccharide (LPS, avoids the activation of p38α-MAPK through an antagonistic engagement of Toll-like receptor (TLR-4. We investigated the fine-tuned mechanism leading to the absence of activation of the p38α-MAPK despite TLR-4 engagement. In macrophages challenged with Escherichia coli LPS or with the LPS from the avirulent variants of C. burnetii, TLR-4 and TLR-2 co-immunoprecipitated. This association was absent in cells challenged by the LPS of pathogenic C. burnetii. The disruption makes TLRs unable to signal during the recognition of the LPS of pathogenic C. burnetii. The disruption of TLR-2 and TLR-4 was induced by the re-organization of the macrophage cytoskeleton by C. burnetii LPS. Interestingly, blocking the actin cytoskeleton re-organization relieved the disruption of the association TLR-2/TLR-4 by pathogenic C. burnetii and rescued the p38α-MAPK activation by C. burnetii. We elucidated an unexpected mechanism allowing pathogenic C. burnetii to avoid activating macrophages by the disruption of the TLR-2 and TLR-4 association.

Polymorphisms in the TLR4 and TLR5 gene are significantly associated with inflammatory bowel disease in German shepherd dogs.

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Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin

2010-12-23

Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease.

Bovine TLR2 and TLR4 mediate Cryptosporidium parvum recognition in bovine intestinal epithelial cells.

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Yang, Zhengtao; Fu, Yunhe; Gong, Pengtao; Zheng, Jingtong; Liu, Li; Yu, Yuqiang; Li, Jianhua; Li, He; Yang, Ju; Zhang, Xichen

2015-08-01

Cryptosporidium parvum (C. parvum) is an intestinal parasite that causes diarrhea in neonatal calves. It results in significant morbidity of neonatal calves and economic losses for producers worldwide. Innate resistance against C. parvum is thought to depend on engagement of pattern recognition receptors. However, the role of innate responses to C. parvum has not been elucidated in bovine. The aim of this study was to evaluate the role of TLRs in host-cell responses during C. parvum infection of cultured bovine intestinal epithelial cells. The expressions of TLRs in bovine intestinal epithelial cells were detected by qRT-PCR. To determine which, if any, TLRs may play a role in the response of bovine intestinal epithelial cells to C. parvum, the cells were stimulated with C. parvum and the expression of TLRs were tested by qRT-PCR. The expression of NF-κB was detected by western blotting. Further analyses were carried out in bovine TLRs transfected HEK293 cells and by TLRs-DN transfected bovine intestinal epithelial cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs. The expression of TLR2 and TLR4 were up-regulated when bovine intestinal epithelial cells were treated with C. parvum. Meanwhile, C. parvum induced IL-8 production in TLR2 or TLR4/MD-2 transfected HEK293 cells. Moreover, C. parvum induced NF-κB activation and cytokine expression in bovine intestinal epithelial cells. The induction of NF-κB activation and cytokine expression by C. parvum were reduced in TLR2-DN and TLR4-DN transfected cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs, and bovine intestinal epithelial cells recognized and responded to C. parvum via TLR2 and TLR4. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microglia Induce Neurotoxic IL-17+ γδ T Cells Dependent on TLR2, TLR4, and TLR9 Activation.

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Katja Derkow

Full Text Available Interleukin-17 (IL-17 acts as a key regulator in central nervous system (CNS inflammation. γδ T cells are an important innate source of IL-17. Both IL-17+ γδ T cells and microglia, the major resident immune cells of the brain, are involved in various CNS disorders such as multiple sclerosis and stroke. Also, activation of Toll-like receptor (TLR signaling pathways contributes to CNS damage. However, the mechanisms underlying the regulation and interaction of these cellular and molecular components remain unclear.In this study, we investigated the crosstalk between γδ T cells and microglia activated by TLRs in the context of neuronal damage. To this end, co-cultures of IL-17+ γδ T cells, neurons, and microglia were analyzed by immunocytochemistry, flow cytometry, ELISA and multiplex immunoassays.We report here that IL-17+ γδ T cells but not naïve γδ T cells induce a dose- and time-dependent decrease of neuronal viability in vitro. While direct stimulation of γδ T cells with various TLR ligands did not result in up-regulation of CD69, CD25, or in IL-17 secretion, supernatants of microglia stimulated by ligands specific for TLR2, TLR4, TLR7, or TLR9 induced activation of γδ T cells through IL-1β and IL-23, as indicated by up-regulation of CD69 and CD25 and by secretion of vast amounts of IL-17. This effect was dependent on the TLR adaptor myeloid differentiation primary response gene 88 (MyD88 expressed by both γδ T cells and microglia, but did not require the expression of TLRs by γδ T cells. Similarly to cytokine-primed IL-17+ γδ T cells, IL-17+ γδ T cells induced by supernatants derived from TLR-activated microglia also caused neurotoxicity in vitro. While these neurotoxic effects required stimulation of TLR2, TLR4, or TLR9 in microglia, neuronal injury mediated by bone marrow-derived macrophages did not require TLR signaling. Neurotoxicity mediated by IL-17+ γδ T cells required a direct cell-cell contact between T

Polymorphisms in the Tlr4 and Tlr5 Gene Are Significantly Associated with Inflammatory Bowel Disease in German Shepherd Dogs

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Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin

2010-01-01

Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease. PMID:21203467

DMPD: The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 17449723 The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. Sh...Show The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. PubmedID 17449723 Title The Tro...ll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. Authors Sheedy F

TLR4 and NKT cell synergy in immunotherapy against visceral leishmaniasis.

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Subir Karmakar

Full Text Available NKT cells play an important role in autoimmune diseases, tumor surveillance, and infectious diseases, providing in most cases protection against infection. NKT cells are reactive to CD1d presented glycolipid antigens. They can modulate immune responses by promoting the secretion of type 1, type 2, or immune regulatory cytokines. Pathogen-derived signals to dendritic cells mediated via Toll like Receptors (TLR can be modulated by activated invariant Natural Killer T (iNKT cells. The terminal β-(1-4-galactose residues of glycans can modulate host responsiveness in a T helper type-1 direction via IFN-γ and TLRs. We have attempted to develop a defined immunotherapeutic, based on the cooperative action of a TLR ligand and iNKT cell using a mouse model of visceral leishmaniasis. We evaluated the anti-Leishmania immune responses and the protective efficacy of the β-(1-4-galactose terminal NKT cell ligand glycosphingophospholipid (GSPL antigen of L. donovani parasites. Our results suggest that TLR4 can function as an upstream sensor for GSPL and provoke intracellular inflammatory signaling necessary for parasite killing. Treatment with GSPL was able to induce a strong effective T cell response that contributed to effective control of acute parasite burden and led to undetectable parasite persistence in the infected animals. These studies for the first time demonstrate the interactions between a TLR ligand and iNKT cell activation in visceral leishmaniasis immunotherapeutic.

Up-regulation of TLR2 and TLR4 in high mobility group Box1-stimulated macrophages in pulpitis patients

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Mahmoudi, Javad; Sabermarouf, Babak; Baradaran, Behzad; Sadat-Hatamnezhad, Leila; Shotorbani, Siamak Sandoghchian

2017-01-01

Objective(s): High Mobility Group Box1 (HMGB1) is a nonhistone, DNA-binding protein that serves a crucial role in regulating gene transcription and is involved in a variety of proinflammatory, extracellular activities. The aim of this study was to explore whether HMGB1 stimulation can up-regulate the expression of Toll-like Receptor 2 (TLR2) and Toll-like Receptor 4 (TLR4) on macrophages from pulpitis and to clarify the subsequent events involving Th17 cells and Th17 cell-associated cytokine changes. Materials and Methods: Having prepared dental pulp tissues of pulpitis and healthy controls, macrophage were isolated and cultured. Macrophages were thereafter stimulated by HMGB1 time course. RT-QPCR, flowcytometer, immunofluorescence, Western blotting, and ELISA techniques were used in the present research. Results: Our results showed that the expression of TLR2 and TLR4 on macrophages stimulated with HMGB1 increased in pulpitis compared with controls (macrophages without HMGB1 stimulation) with a statistical significance (Ppulpitis increased, and NF-kB, the downstream target of TLR2 and TLR4, also showed a marked elevation after macrophages’ stimulation by HMGB1. Conclusion: The evidence from the present study suggests that the enhanced TLR2 and TLR4 pathways and Th17 cell polarization may be due to HMGB1 stimulation in pulpitis. PMID:28293399

Amitriptyline and aerobic exercise or amitriptyline alone in the treatment of chronic migraine: a randomized comparative study

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Michelle Dias Santos Santiago

2014-11-01

Full Text Available To compare the preventive treatment benefits of amitriptyline and aerobic exercise or amitriptyline alone in patients with chronic migraine. Method Sixty patients, both genders, aged between 18 and 50 years, with a diagnosis of chronic migraine, were randomized in groups called amitriptyline and aerobic exercise or amitriptyline alone. The following parameters were evaluated: headache frequency, intensity and duration of headache, days of the analgesic medication use, body mass index (BMI, Beck Depression Inventory (BDI and Beck Anxiety Inventory (BAI scores. Results In the evaluated parameters, was observed decrease in headache frequency (p=0.001, moderate intensity (p=0.048, in headache duration (p=0.001, the body mass index (p=0.001, Beck Depression Inventory (p=0.001 and Beck Anxiety Inventory scores (p=0.001, when groups were compared in the end of third month. Conclusion In this study, the amitriptyline was an effective treatment for chronic migraine, but its efficacy was increased when combined with aerobic exercise.

Role of TLR4 gene polymorphisms in the colorectal cancer risk ...

African Journals Online (AJOL)

Saniya Nissar

2016-05-26

May 26, 2016 ... This is an open access article under the CC BY-NC-ND license ... eliminate infectious pathogens and cancer debris [5–7]. The TLR4 gene is .... evidence of involvement of TLR4 gene in driving CRC and this. TLR4 may serve ...

Amitriptyline Cardiac Toxicity Treated with Hemoperfusion

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Nurdan Ünlü

2017-04-01

Full Text Available Tricyclic antidepressant intoxication is frequently encountered among children and adults due to widespread use of the drugs. Amitriptyline is among the major tricyclic antidepressants. It affects the cardiovascular, respiratory and central nervous system. In the treatment of amitriptyline intoxication, various treatments such as gastric lavage, activated charcoal, bicarbonate infusion, antiarrhythmic, and anticonvulsant drug usage were applied. Here, we reported a patient with severe amitriptyline intoxication who did not respond to these treatments but dramatically improved with hemoperfusion. A 33 year-old woman applied to the emergency service half an hour later ingesting 2000 mg of amitriptyline as a suicide attempt. On admission, her Glasgow coma scale (GCS was 10, blood pressure was 100/60 mmHg, heart rate was 160 beats/min. Wide QRS and ventricular tachycardia was seen in the Electrocardiography (ECG results. Having her GCS regressed to 7, she was intubated and admitted to intensive care unit after the initial treatments. Hemoperfusion was commenced within half an hour. While hemoperfusion was continuing, her ECG was seen to turn to sinus tachycardia. Her cardiovascular and neurological status returned to normal on the 2nd day and she was discharged from the intensive care unit on the 4th day. Besides hemoperfusion is not recommended due to high protein binding and large volume of distribution in classical treatment of amitriptyline overdose, current reports representing efficacy of hemoperfusion are also accumulating. After ingestion, tricyclic antidepressants are absorbed rapidly and reach to their effective concentration in the tissues, especially by the lung, the brain and the heart. Hence, hemoperfusion performed in early stage of ingestion is an effective treatment and in cases that do not respond to conventional therapies, it should be considered that this method can be used in the early period.

Customized laboratory TLR4 and TLR2 detection method from peripheral human blood for early detection of doxorubicin-induced cardiotoxicity.

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Pop-Moldovan, A L; Trofenciuc, N-M; Dărăbanţiu, D A; Precup, C; Branea, H; Christodorescu, R; Puşchiţă, M

2017-05-01

Cancer treatments can have significant cardiovascular adverse effects that can cause cardiomyopathy and heart failure with reduced survival benefit and considerable decrease in the use of antineoplastic therapy. The purpose of this study is to assess the role of TLR2 and TLR4 gene expression as an early marker for the risk of doxorubicin-induced cardiomyopathy in correlation with early diastolic dysfunction in patients treated with doxorubicin. Our study included 25 consecutive patients who received treatment with doxorubicin for hematological malignancies (leukemia, lymphomas or multiple myeloma), aged 18-65 years, with a survival probability>6 months and with left ventricular ejection fraction>50%. Exclusion criteria consisted of the following: previous anthracycline therapy, previous radiotherapy, history of heart failure or chronic renal failure, atrial fibrillation, and pregnancy. In all patients, in fasting state, a blood sample was drawn for the assessment of TLR2 and TLR4 gene expression. Gene expression was assessed by quantitative reverse transcription PCR (qRT-PCR) using blood collection, RNA isolation, cDNA reverse transcription, qRT-PCR and quantification of the relative expression. At enrollment, all patients were evaluated clinically; an ECG and an echocardiography were performed. The average amount of gene expression units was 0.113 for TLR4 (range 0.059-0.753) and 0.218 for TLR2 (range 0.046-0.269). The mean mRNA extracted quantity was 113 571 ng/μl. As for the diastolic function parameters, criteria for diastolic dysfunction were present after 6 months in 16 patients (64%). In these patients, the mean values for TLR4 were 0.1198625 and for TLR2 were 0.16454 gene expression units. As for the diastolic function parameters, criteria for diastolic dysfunction were present after 6 months in 16 patients (64%). In these patients, the mean value for TLR2 was 0.30±0.19 and for TLR4 was 0.15±0.04. The corresponding values for the patients who did not

The effects of Ostertagia occidentalis somatic antigens on ovine TLR2 and TLR4 expression

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Hassan BORJI

2015-10-01

Full Text Available Background: Recognition of helminth-derived pathogen associated molecular patterns (PAMPs by pattern recognition receptors (PRRs, including toll like recep­tors (TLRs is the first step towards initiating anti–helminth immune re­sponses.Methods: Using somatic antigens of Ostertagia occidentalis, an important abomasal parasite of ruminants, the expression of ovine TLR2 and TLR4 in peripheral blood mononuclear cells (PBMCs was analyzed by real-time quatitative reverse-transcrip­tion polymerase chain reaction (qRT-PCR. Somatic antigens of O. occidentalis were prepared to stimulate ovine PBMCs in a time and dose dependent manner.Results: A high expression of TLR2 and TLR4 was observed in PBMCs cultured with somatic antigens of the parasites specially when PBMCs were cultured with 100 µg/ml of somatic antigens and incubated for 2h. Up-regulation of TLR2 expres­sion was more pronounced and evident in our study.Conclsusion: Somatic antigens of O. occidentalis have immunostimulatory and domi­nant role on peripheral immune cells. This study provide for the first time evidence of induction of TLRs in ovine PBMCs by somatic antigen of O. occidentalis

The combination of maltose-binding protein and BCG-induced Th1 activation is involved in TLR2/9-mediated upregulation of MyD88-TRAF6 and TLR4-mediated downregulation of TRIF-TRAF3.

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Liu, Guomu; Zhai, Xiaoyu; Zhou, Hongyue; Yang, Xiaoyu; Zhang, Nannan; Tai, Guixiang; Ni, Weihua

2018-03-01

Our previous study demonstrated that maltose-binding protein (MBP) activated Th1 through the TLR2-mediated MyD88-dependent pathway and the TLR4-mediated TRIF-dependent pathway. The combination of MBP and BCG synergistically induced Th1 activation, and the TLR2/9-mediated MyD88-dependent pathway is involved in this process. To further explore this mechanism, we stimulated purified mouse CD4 + T cells with MBP and BCG in vitro. The results demonstrated that MBP combined with BCG synergistically increased IFN-γ production and TLR2/4/9 expression, suggesting the involvement of TLR2/4/9 in the combination-induced Th1 activation. Next, TLRs 2/4/9 were blocked to analyze the effects of TLRs on Th1 activation. The results demonstrated that MBP induced a low level of Th1 activation by upregulating TLR2-mediated MyD88-TRAF6 and TLR4-mediated TRIF-TRAF3 expression, whereas MBP combined with BCG induced synergistic Th1 activation, which was not only triggered by strong upregulation of TLR2/9-mediated MyD88-TRAF6 expression but also by shifting TLR4-mediated TRIF-TRAF3 into the TRIF-TRAF6 pathway. Moreover, we observed that a TLR4 antibody upregulated MyD88 expression and a TLR9 inhibitor downregulated TRIF expression, indicating that there was cross-talk between TLRs 2/4/9 in MBP combined with BCG-induced Th1 activation. Our findings may expand the knowledge regarding TLR cross-talk involved in regulating the Th1 response. Copyright © 2018 Elsevier Inc. All rights reserved.

Coenzyme Q10 and alpha-tocopherol protect against amitriptyline toxicity

International Nuclear Information System (INIS)

Cordero, Mario D.; Moreno-Fernandez, Ana Maria; Gomez-Skarmeta, Jose Luis; Miguel, Manuel de; Garrido-Maraver, Juan; Oropesa-Avila, Manuel; Rodriguez-Hernandez, Angeles; Navas, Placido; Sanchez-Alcazar, Jose Antonio

2009-01-01

Since amitriptyline is a very frequently prescribed antidepressant drug, it is not surprising that amitriptyline toxicity is relatively common. Amitriptyline toxic systemic effects include cardiovascular, autonomous nervous, and central nervous systems. To understand the mechanisms of amitriptyline toxicity we studied the cytotoxic effects of amitriptyline treatment on cultured primary human fibroblasts and zebrafish embryos, and the protective role of coenzyme Q 10 and alpha-tocopherol, two membrane antioxidants. We found that amitriptyline treatment induced oxidative stress and mitochondrial dysfunction in primary human fibroblasts. Mitochondrial dysfunction in amitriptyline treatment was characterized by reduced expression levels of mitochondrial proteins and coenzyme Q 10 , decreased NADH:cytochrome c reductase activity, and a drop in mitochondrial membrane potential. Moreover, and as a consequence of these toxic effects, amitriptyline treatment induced a significant increase in apoptotic cell death activating mitochondrial permeability transition. Coenzyme Q 10 and alpha-tocopherol supplementation attenuated ROS production, lipid peroxidation, mitochondrial dysfunction, and cell death, suggesting that oxidative stress affecting cell membrane components is involved in amitriptyline cytotoxicity. Furthermore, amitriptyline-dependent toxicity and antioxidant protection were also evaluated in zebrafish embryos, a well established vertebrate model to study developmental toxicity. Amitriptyline significantly increased embryonic cell death and apoptosis rate, and both antioxidants provided a significant protection against amitriptyline embryotoxicity

Evidence for a developmental role for TLR4 in learning and memory.

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Eitan Okun

Full Text Available Toll-like receptors (TLRs play essential roles in innate immunity and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain where they mediate responses to infection, stress and injury. Very little is known about the roles of TLRs in cognition. To test the hypothesis that TLR4 has a role in hippocampus-dependent spatial learning and memory, we used mice deficient for TLR4 and mice receiving chronic TLR4 antagonist infusion to the lateral ventricles in the brain. We found that developmental TLR4 deficiency enhances spatial reference memory acquisition and memory retention, impairs contextual fear-learning and enhances motor functions, traits that were correlated with CREB up-regulation in the hippocampus. TLR4 antagonist infusion into the cerebral ventricles of adult mice did not affect cognitive behavior, but instead affected anxiety responses. Our findings indicate a developmental role for TLR4 in shaping spatial reference memory, and fear learning and memory. Moreover, we show that central TLR4 inhibition using a TLR4 antagonist has no discernible physiological role in regulating spatial and contextual hippocampus-dependent cognitive behavior.

Phase 1A safety assessment of intravenous amitriptyline

NARCIS (Netherlands)

Fridrich, Peter; Colvin, Hans Peter; Zizza, Anthony; Wasan, Ajay D.; Lukanich, Jean; Lirk, Philipp; Saria, Alois; Zernig, Gerald; Hamp, Thomas; Gerner, Peter

2007-01-01

The antidepressant amitriptyline is used as an adjuvant in the treatment of chronic pain. Among its many actions, amitriptyline blocks Na+ channels and nerves in several animal and human models. As perioperative intravenous lidocaine has been suggested to decrease postoperative pain, amitriptyline,

Significance of TLR4/MyD88 expression in breast cancer

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Chen, Xiangjin; Zhao, Feng; Zhang, Huihao; Zhu, Youzhi; Wu, Kunlin; Tan, Guozheng

2015-01-01

Objective: To investigate the expression of TLR4/MyD88 in breast cancer, and explore the relationship between their expression and breast cancer tumor growth and invasion. Methods: We examined the protein expression of TLR4 and MyD88 in 60 cases of histologically confirmed breast cancer. The relationship of their protein expressions with clinical features including age at diagnosis, tumor size and stage, lymph node metastasis and distant metastasis were analyzed. Results: The IHC results showed that TLR4 and MyD88 were expressed in 63.3% (38/60) and 58.3% (35/60) of malignant breast tumors respectively. TLR4 expression in breast cancer were significantly higher than in fibroadenoma (n = 4, 20.0%) and adjacent normal tissues (n = 2, 10.0%) (P fibroadenoma (n = 4, 20.0%) and adjacent normal tissue (n = 3, 15.0%) (P fibroadenoma and adjacent normal tissues (P < 0.05). The protein expressions of TLR4 and MyD88 were also significantly associated with poor clinical features (P < 0.05). Conclusion: TLR4 and MyD88 expression might be associated with breast cancer growth and regional and distant metastases. PMID:26261595

Toll-like receptor 4 (TLR4) impairs nitric oxide contributing to Angiotensin II-induced cavernosal dysfunction.

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Nunes, Kenia P; Bomfim, Gisele F; Toque, Haroldo A; Szasz, Theodora; Clinton Webb, R

2017-12-15

Angiotensin II (AngII), a corpus cavernosum (CC) constrictor peptide, modulates Toll like receptor (TLR) expression, a key element of the innate immune system, contributing to impaired vascular function in pathological conditions. However, it is unknown whether TLR4 is involved in AngII-induced erectile dysfunction. In this study, we investigated whether TLR4 plays a role in cavernosal dysfunction caused by AngII upregulation. Cavernosal smooth muscle cells (CSMC) from C57/BL6 mice were treated with AngII (0.1μM) or bacterial LPS (50ng/ml) for 12-24h and TLR4 expression was assessed. Mice were infused with AngII (90ng/min, 28days) and treated with anti-TLR4 antibody (0.1mg/daily, i.p.) for the last 14days of the treatment. CC tissue was used for functional studies and for Western blotting. Nitric Oxide Synthase (NOS) activity was measured by conversion of [ 3 H]-l-arginine to [ 3 H]-l-citrulline, systemic TNF-α levels by ELISA, and reactive oxygen species (ROS) by immunofluorescence. We report upregulation of TLR4 in CSMC following AngII or LPS stimulation. In AngII-infused mice, chronic treatment with anti-TLR4 antibody (28±2.1%) attenuates adrenergic CC contraction, which also ameliorates nitrergic (68.90±0.21 vs. 51.07±0.63, 8Hz, AngII-infused mice treated vs. non-treated). Decreased endothelial NOS expression, reduced NOS activity, and augmented levels of TNF-α, and ROS were found following AngII-infusion. These alterations were prevented, or at least decreased by anti-TLR4 antibody treatment. Inhibition of TLR4 ameliorates AngII-impaired cavernosal relaxation, decreases TNF-α levels, and restores NO bioavailability, demonstrating that TLR4 partly mediates AngII-induced cavernosal dysfunction. Copyright © 2017. Published by Elsevier Inc.

Single-nucleotide polymorphisms in Toll-like receptor (TLR)-2, TLR4 and heat shock protein 70 genes and susceptibility to scrub typhus.

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Janardhanan, Jeshina; Joseph Martin, Sherry; Astrup, Elisabeth; Veeramanikandan, R; Aukrust, Pål; Abraham, Ooriapadickal C; Varghese, George M

2013-11-01

Scrub typhus is a highly prevalent bacterial infection in India and South Asia that is caused by Orientia tsutsugamushi. The innate immune response to infections is modulated by Toll-like receptors (TLRs) and heat shock proteins (HSPs). This study was done to assess the prevalence and possible association of TLR and HSP polymorphisms in scrub typhus. TLR4 Asp299Gly, TLR4 Thr399Ile, TLR2 Arg753Gln and HSP70-2 A1267G are single-nucleotide polymorphisms (SNPs) that may modulate their activities, and these SNPs were assessed in 137 scrub typhus patients and 134 controls by PCR restriction fragment length polymorphism. We found that the two TLR4 mutations, TLR4 D299G and TLR4T399I, were present in 19.5% and 22% of the study population, respectively, and was in significant linkage disequilibrium with a D' of 0.8. The TLR2 mutation was found to be rare, whereas the HSP A>G mutation was very common (77.5%). Compared with the controls, the prevalence of heterozygous genotype of the TLR4D299G SNP, but not any of the other SNPs, was significantly higher among scrub typhus patients. Further studies using a larger sample size and more candidate genes may better enable in determining the role of these associations in susceptibility and severity of scrub typhus.

Long-Term Pulmonal Therapy of Cystic Fibrosis-Patients with Amitriptyline

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Constantin Adams

2016-07-01

Full Text Available Background/Aims: Several recent clinical studies revealed an accumulation of ceramide in bronchial epithelial cells of patients with cystic fibrosis (CF. Degradation of ceramide concentrations in lungs of CF patients employing the functional acid sphingomyelinase inhibitor amitriptyline revealed a benefit in lung function, weight and exacerbation rates. Methods: To test for a beneficial effect of amitriptyline in vivo, we performed two phase II randomised, double-blind, placebo-controlled studies. CF patients were treated with 25 mg amitriptyline twice daily, i.e. a total dose of 50 mg/d. After those two studies part of the patients used amitriptyline in an off-lable-use for routine treatment. These patients were observed after one, two and three years after continuous use of amitriptyline and were matched with those patients who were not treated. These patients were used as a control group. Results: After one year of treatment, forced expiratory volume in 1 sec predicted (FEV1 increased significantly by 7.6±7.0%, p=1 decreased significantly in the control group by 1.8±3.3%, p=0.010, and weight increased by 1.1±2.7kg, p=0.010 (n=14. After two years of treatment, FEV1 increased significantly by 5.6±10.3%, p=0.009, and weight increased by 3.6±2.9kg, p=1 decreased in the control group by 2.1±3.7%, p=0.051 and weight increased by only 0.4±2.9kg, p=0.31 (n=10. After three years of treatment, FEV1 increased significantly by 7.7±8%, p=0.050, and weight increased by 7.3±3.8kg, p=0.016, in the amitriptyline population (n=5, whereas FEV1 decreased in the control group by 1.0±1.3%, p=0.075 and weight increased by 0.4±1.5kg, p=0.29 (n=5. Conclusion: Amitriptyline significantly increases FEV1, reduces ceramide in lung cells and increases weight of CF patients.

Identification of the key differential transcriptional responses of human whole blood following TLR2 or TLR4 ligation in-vitro.

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Simon Blankley

Full Text Available The use of human whole blood for transcriptomic analysis has potential advantages over the use of isolated immune cells for studying the transcriptional response to pathogens and their products. Whole blood stimulation can be carried out in a laboratory without the expertise or equipment to isolate immune cells from blood, with the added advantage of being able to undertake experiments using very small volumes of blood. Toll like receptors (TLRs are a family of pattern recognition receptors which recognise highly conserved microbial products. Using the TLR2 ligand (Pam3CSK4 and the TLR4 ligand (LPS, human whole blood was stimulated for 0, 1, 3, 6, 12 or 24 hours at which times mRNA was isolated and a comparative microarray was undertaken. A common NFκB transcriptional programme was identified following both TLR2 and TLR4 ligation which peaked at between 3 to 6 hours including upregulation of many of the NFκB family members. In contrast an interferon transcriptional response was observed following TLR4 but not TLR2 ligation as early as 1 hour post stimulation and peaking at 6 hours. These results recapitulate the findings observed in previously published studies using isolated murine and human myeloid cells indicating that in vitro stimulated human whole blood can be used to interrogate the early transcriptional kinetic response of innate cells to TLR ligands. Our study demonstrates that a transcriptomic analysis of mRNA isolated from human whole blood can delineate both the temporal response and the key transcriptional differences following TLR2 and TLR4 ligation.

TLR-2 and TLR-4 expression in monocytes of newborns with late-onset sepsis,

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Ana C.C. Redondo

2014-09-01

Full Text Available Objetivos: Analisar a expressão dos TLR-2 e TLR-4 em monócitos de recém-nascidos com sepse tardia. Métodos: Trata-se de um estudo prospectivo com 27 recém-nascidos a termo entre 8 e 29 dias de vida com diagnóstico clínico e laboratorial de sepse tardia dos quais dez (37% apresentaram cultura positiva. As citocinas foram determinadas por teste de CBA em sangue periférico enquanto que a expressão e MFI (mediana de intensidade de fluorescência dos TLR-2 e TLR-4 foi determinado por imunofenotipagem em monócitos de sangue periférico total através de análise pelo citômetro de fluxo BD FACSDiva. O grupo usado para comparação foi de adultos saudáveis. Resultados: Microrganismos foram identificados em 37% dos pacientes e estes juntamente com os pacientes com sepse clínica tiveram níveis elevados de citocinas pró-inflamatórias (IL-8, IL-6, IL-1β e de citocina anti-inflamatória (IL-10 corroborando o processo inflamatório/infeccioso. No monócito, a frequência de expressão do TLR-4 foi mais elevada (p = 0,01. Conclusões: Este estudo analisou a resposta imune inata no recém-nascido com sepse. Recémnascidos sépticos que dependem quase exclusivamente do sistema imune inato apresentaram pouca resposta in vivo na ativação de monócitos o que sugere uma resposta imune deficiente e maior susceptibilidade à infecção.

Cellular uptake of exogenous calcineurin B is dependent on TLR4/MD2/CD14 complexes, and CnB is an endogenous ligand of TLR4.

Science.gov (United States)

Yang, Jinju; Qin, Nannan; Zhang, Hongwei; Yang, Rui; Xiang, Benqiong; Wei, Qun

2016-04-19

Our previous research showed that recombinant calcineurin B (rhCnB) stimulates cytokine secretion by immune cells, probably through TLR4. Exogenous CnB can be incorporated into many different tumour cells in vitro, but the mode of uptake and receptors required remain unknown. Here, we report that exogenous CnB is taken up by cells in a time- and concentration-dependent manner via clathrin-dependent receptor-mediated internalization. Our findings further confirm that uptake is mediated by the TLR4/MD2 complex together with the co-receptor CD14. The MST results revealed a high affinity between CnB and the TLR4 receptor complex. No binding was detected between CnB and LPS. CnB inhibited the uptake of LPS, and LPS also inhibited the uptake of CnB. These results indicate that the uptake of exogenous CnB did not occur through LPS and that CnB was not a chaperone of LPS. Thus, we conclude that TLR4 receptor complexes were required for the recognition and internalization of exogenous CnB. CnB could be a potential endogenous ligand of TLR4 and function as an agonist of TLR4. These properties of CnB support its potential for development as an anti-cancer drug.

An unusual dimeric structure and assembly for TLR4 regulator RP105-MD-1

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Yoon, Sung-il; Hong, Minsun; Wilson, Ian A [Scripps

2011-11-16

RP105-MD-1 modulates the TLR4-MD-2-mediated, innate immune response against bacterial lipopolysaccharide (LPS). The crystal structure of the bovine 1:1 RP105-MD-1 complex bound to a putative endogenous lipid at 2.9 Å resolution shares a similar overall architecture to its homolog TLR4-MD-2 but assembles into an unusual 2:2 homodimer that differs from any other known TLR-ligand assembly. The homodimer is assembled in a head-to-head orientation that juxtaposes the N-terminal leucine-rich repeats (LRRs) of the two RP105 chains, rather than the usual tail-to-tail configuration of C-terminal LRRs in ligand-activated TLR dimers, such as TLR1-TRL2, TLR2-TLR6, TLR3-TLR3 and TLR4-TLR4. Another unusual interaction is mediated by an RP105-specific asparagine-linked glycan, which wedges MD-1 into the co-receptor binding concavity on RP105. This unique mode of assembly represents a new paradigm for TLR complexes and suggests a molecular mechanism for regulating LPS responses.

[Changes of FoxP3, CD4(+)CD25(+) regulatory T cells, TLR2 and TLR9 in children with infectious mononucleosis].

Science.gov (United States)

Wang, Qiang; Wang, Zuo-Feng; Cao, Mei; Wang, Zhi-Ying

2013-04-01

The aim of this study was to investigate the effects of TLR2, TLR9, CD4(+)CD25(+) regulatory T cells (Treg) and transcription factor FoxP3 in the pathogenesis of children with infectious mononucleosis (IM). Thirty-five acute IM patients admitted in our hospital from April 2010 to January 2011 were enrolled in this study. Thirty-five healthy subjects were taken as control. The thirty-five patients before treatment were considered as patients in acute stage, after treatment and without clinical symptom they were thought as patients in recovery stage. The expression levels of TLR2, TLR9 and FoxP3 mRNA were detected by real time PCR using SYBR Green I. The expression of T lymphocyte subset CD4(+)CD25(+) in peripheral blood mononuclear cells was detected by flow cytometry. The results showed that the relative levels of TLR2 mRNA (4.03 ± 0.56), TLR9 mRNA (8.88 ± 1.56) in peripheral blood mononuclear cells of IM patients in acute stage were significantly higher than those of the controls [TLR2 mRNA (2.22 ± 0.57), TLR9 mRNA (3.63 ± 1.30)] and IM patients in recovery stage [TLR2 mRNA (2.76 ± 0.83), TLR9 mRNA (5.34 ± 1.60)] (P 0.05). It is concluded that the expression of CD4(+)CD25(+)regulatory T cells is reduced, and its special transcription factor FoxP3 mRNA is down-regulated, but expression levels of TLR2 mRNA, TLR9 mRNA are up-regulated in IM patients of acute stage.

Microglia are required for astroglial toll-like receptor 4 response and for optimal TLR2 and TLR3 response

DEFF Research Database (Denmark)

Holm, Thomas H; Draeby, Dina; Owens, Trevor

2012-01-01

Within the central nervous system, astrocytes and microglia are the primary responders to endogenous ligands released upon injury and stress, as well as to infectious pathogens. Toll-like receptors (TLRs) are implicated in recognition of both types of stimulus. Whether astrocytes respond as stron......Within the central nervous system, astrocytes and microglia are the primary responders to endogenous ligands released upon injury and stress, as well as to infectious pathogens. Toll-like receptors (TLRs) are implicated in recognition of both types of stimulus. Whether astrocytes respond...... astrocytes from mixed glial cultures and measured their response to TLR agonists. Our results show that the response of astrocytes to TLR2 and TLR3 agonists is greatly enhanced by, and response to TLR4 agonists is completely dependent on, the presence of functional microglia. In the case of the TLR4 response...

Small Interference RNA Targeting TLR4 Gene Effectively Attenuates Pulmonary Inflammation in a Rat Model

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Feixiang Wu

2012-01-01

Full Text Available Objective. The present study was to investigate the feasibility of adenovirus-mediated small interference RNA (siRNA targeting Toll-like receptor 4 (TLR4 gene in ameliorating lipopolysaccharide- (LPS- induced acute lung injury (ALI. Methods. In vitro, alveolar macrophages (AMs were treated with Ad-siTLR4 and Ad-EFGP, respectively, for 12 h, 24 h, and 48 h, and then with LPS (100 ng/mL for 2 h, and the function and expression of TLR4 were evaluated. In vivo, rats received intratracheal injection of 300 μL of normal saline (control group, 300 μL of Ad-EGFP (Ad-EGFP group, or 300 μL of Ad-siTLR4 (Ad-siTLR4 group and then were intravenously treated with LPS (50 mg/kg to induce ALI. Results. Ad-siTLR4 treatment significantly reduced TLR4 expression and production of proinflammatory cytokines following LPS treatment both in vitro and in vivo. Significant alleviation of tissue edema, microvascular protein leakage, and neutrophil infiltration was observed in the AdsiTLR4-treated animals. Conclusion. TLR4 plays a critical role in LPS-induced ALI, and transfection of Ad-siTLR4 can effectively downregulate TLR4 expression in vitro and in vivo, accompanied by alleviation of LPS-induced lung injury. These findings suggest that TLR4 may serve as a potential target in the treatment of ALI and RNA interfering targeting TLR4 expression represents a therapeutic strategy.

TLR4 plays a crucial role in MSC-induced inhibition of NK cell function

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Lu, Ying [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Liu, Jin; Liu, Yang; Qin, Yaru [Beijing Institute of Radiation Medicine, Beijing (China); Luo, Qun [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Wang, Quanli, E-mail: 13691110351@163.com [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Duan, Haifeng, E-mail: duanhf0720@163.com [Beijing Institute of Radiation Medicine, Beijing (China)

2015-08-21

Mesenchymal stem cells (MSC) are a kind of stromal cell within the tumor microenvironment. In our research, MSC derived from acute myeloid leukemia patients' bone marrow (AML-MSC) and lung cancer tissues (LC-MSC) as well as normal bone marrow-derived MSC (BM-MSC) cultured in conditioned medium of HeLa cells were found to have higher expressions of Toll-like receptor (TLR4) mRNA compared with BM-MSC. The sorted TLR4-positive MSC (TLR4+ MSC) differed in cytokine (interleukin-6, interleukin-8, and monocyte chemoattractant protein-1) secretion from those of unsorted MSC. MSC was reported to inhibit natural killer (NK) cell proliferation and function. In this research, we confirmed that TLR4+ MSC aggravate this suppression. Furthermore, when TLR4 in the sorted cells were stimulated by LPS or following blocked by antibody, the suppression on NK cell proliferation and cytotoxicity were more intensive or recovered respectively. Compared to unsorted MSC, NKG2D receptor expression on NK cells were also inhibited by TLR4+ MSC. These findings suggest that activation of TLR4 pathway is important for TLR4+ MSC and MSC to obstruct anti-tumor immunity by inhibiting NK cell function, which may provide a potential stroma-targeted tumor therapy. - Highlights: • TLR4+ MSC inhibit NK cell proliferation in vivo and in vitro. • TLR4+ MSC inhibit NKG2D expression on NK cells and NK cell cytotoxicity. • The distinguished cytokine expression of TLR4+ MSC may contribute to the inhibition on NK cell function.

Toll like receptor 4 (TLR4) mediates the stimulating activities of chitosan oligosaccharide on macrophages.

Science.gov (United States)

Zhang, Pei; Liu, Weizhi; Peng, Yanfei; Han, Baoqin; Yang, Yan

2014-11-01

The in vivo and in vitro immunostimulating properties of chitosan oligosaccharide (COS) prepared by enzymatic hydrolysis of chitosan and the mechanisms mediating the effects were investigated. Our data showed that the highly active chitosanase isolated could hydrolyze chitosan to the polymerization degree of 3-8. The resulting COS was an efficient immunostimulator. COS markedly enhanced the proliferation and neutral red phagocytosis by RAW 264.7 macrophages. The production of nitric oxide (NO) and tumor necrosis factor alpha (TNF-α) by macrophages was significantly increased after incubation with COS. Oral administration of COS in mice could increase spleen index and serum immunoglobin G (IgG) contents. COS was labeled with FITC to study the pinocytosis by macrophages. Results showed that FITC-COS was phagocyted by macrophages and anti-murine TLR4 antibody completely blocked FITC-COS pinocytosis. RT-PCR indicated that COS treatment of macrophages significantly increased TLR4 and inducible nitric oxide synthase (iNOS) mRNA levels. When cells were pretreated with anti-murine TLR4 antibody, the effect of COS on TLR4 and iNOS mRNA induction was decreased. COS-induced NO secretion by macrophages was also markedly decreased by anti-murine TLR4 antibody pretreatment. In conclusion, the present study revealed that COS possesses potent immune-stimulating properties by activating TLR4 on macrophages. Copyright © 2014 Elsevier B.V. All rights reserved.

Respiratory Syncytial Virus Fusion Protein-Induced Toll-Like Receptor 4 (TLR4) Signaling Is Inhibited by the TLR4 Antagonists Rhodobacter sphaeroides Lipopolysaccharide and Eritoran (E5564) and Requires Direct Interaction with MD-2

Science.gov (United States)

Rallabhandi, Prasad; Phillips, Rachel L.; Boukhvalova, Marina S.; Pletneva, Lioubov M.; Shirey, Kari Ann; Gioannini, Theresa L.; Weiss, Jerrold P.; Chow, Jesse C.; Hawkins, Lynn D.; Vogel, Stefanie N.; Blanco, Jorge C. G.

2012-01-01

ABSTRACT Respiratory syncytial virus (RSV) is a leading cause of infant mortality worldwide. Toll-like receptor 4 (TLR4), a signaling receptor for structurally diverse microbe-associated molecular patterns, is activated by the RSV fusion (F) protein and by bacterial lipopolysaccharide (LPS) in a CD14-dependent manner. TLR4 signaling by LPS also requires the presence of an additional protein, MD-2. Thus, it is possible that F protein-mediated TLR4 activation relies on MD-2 as well, although this hypothesis has not been formally tested. LPS-free RSV F protein was found to activate NF-κB in HEK293T transfectants that express wild-type (WT) TLR4 and CD14, but only when MD-2 was coexpressed. These findings were confirmed by measuring F-protein-induced interleukin 1β (IL-1β) mRNA in WT versus MD-2−/− macrophages, where MD-2−/− macrophages failed to show IL-1β expression upon F-protein treatment, in contrast to the WT. Both Rhodobacter sphaeroides LPS and synthetic E5564 (eritoran), LPS antagonists that inhibit TLR4 signaling by binding a hydrophobic pocket in MD-2, significantly reduced RSV F-protein-mediated TLR4 activity in HEK293T-TLR4–CD14–MD-2 transfectants in a dose-dependent manner, while TLR4-independent NF-κB activation by tumor necrosis factor alpha (TNF-α) was unaffected. In vitro coimmunoprecipitation studies confirmed a physical interaction between native RSV F protein and MD-2. Further, we demonstrated that the N-terminal domain of the F1 segment of RSV F protein interacts with MD-2. These data provide new insights into the importance of MD-2 in RSV F-protein-mediated TLR4 activation. Thus, targeting the interaction between MD-2 and RSV F protein may potentially lead to novel therapeutic approaches to help control RSV-induced inflammation and pathology. PMID:22872782

S100A9 interaction with TLR4 promotes tumor growth.

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Eva Källberg

Full Text Available By breeding TRAMP mice with S100A9 knock-out (S100A9(-/- animals and scoring the appearance of palpable tumors we observed a delayed tumor growth in animals devoid of S100A9 expression. CD11b(+ S100A9 expressing cells were not observed in normal prostate tissue from control C57BL/6 mice but were readily detected in TRAMP prostate tumors. Also, S100A9 expression was observed in association with CD68(+ macrophages in biopsies from human prostate tumors. Delayed growth of TRAMP tumors was also observed in mice lacking the S100A9 ligand TLR4. In the EL-4 lymphoma model tumor growth inhibition was observed in S100A9(-/- and TLR4(-/-, but not in RAGE(-/- animals lacking an alternative S100A9 receptor. When expression of immune-regulating genes was analyzed using RT-PCR the only common change observed in mice lacking S100A9 and TLR4 was a down-regulation of TGFβ expression in splenic CD11b(+ cells. Lastly, treatment of mice with a small molecule (ABR-215050 that inhibits S100A9 binding to TLR4 inhibited EL4 tumor growth. Thus, S100A9 and TLR4 appear to be involved in promoting tumor growth in two different tumor models and pharmacological inhibition of S100A9-TLR4 interactions is a novel and promising target for anti-tumor therapies.

S100A9 Interaction with TLR4 Promotes Tumor Growth

Science.gov (United States)

Källberg, Eva; Vogl, Thomas; Liberg, David; Olsson, Anders; Björk, Per; Wikström, Pernilla; Bergh, Anders; Roth, Johannes; Ivars, Fredrik; Leanderson, Tomas

2012-01-01

By breeding TRAMP mice with S100A9 knock-out (S100A9−/−) animals and scoring the appearance of palpable tumors we observed a delayed tumor growth in animals devoid of S100A9 expression. CD11b+ S100A9 expressing cells were not observed in normal prostate tissue from control C57BL/6 mice but were readily detected in TRAMP prostate tumors. Also, S100A9 expression was observed in association with CD68+ macrophages in biopsies from human prostate tumors. Delayed growth of TRAMP tumors was also observed in mice lacking the S100A9 ligand TLR4. In the EL-4 lymphoma model tumor growth inhibition was observed in S100A9−/− and TLR4−/−, but not in RAGE−/− animals lacking an alternative S100A9 receptor. When expression of immune-regulating genes was analyzed using RT-PCR the only common change observed in mice lacking S100A9 and TLR4 was a down-regulation of TGFβ expression in splenic CD11b+ cells. Lastly, treatment of mice with a small molecule (ABR-215050) that inhibits S100A9 binding to TLR4 inhibited EL4 tumor growth. Thus, S100A9 and TLR4 appear to be involved in promoting tumor growth in two different tumor models and pharmacological inhibition of S100A9-TLR4 interactions is a novel and promising target for anti-tumor therapies. PMID:22470535

Genetic variation at Exon2 of TLR4 gene and its association with ...

African Journals Online (AJOL)

This study was conducted to analyze the polymorphisms of chicken Toll-like receptors 4(TLR4) gene and aimed to provide a theoretical foundation for a further research on correlation between chicken TLR4 gene and disease resistance. Genetic variations at exon 2 of TLR4 gene in 14 chicken breeds and the red jungle ...

TLR4 activates NF-κB in human ovarian granulosa tumor cells

International Nuclear Information System (INIS)

Woods, Dori C.; White, Yvonne A.R.; Dau, Caroline; Johnson, A.L.

2011-01-01

Highlights: → TLR4 is expressed in human ovarian granulosa tumor cells. → Acting through TLR4, LPS and HSP60 induce a NFκB signaling cascade in human ovarian granulosa tumor cells. → NFκB activation or inhibition did not alter chemosensitivity to TRAIL or cisplatin. -- Abstract: Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-κB) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to IκB degradation and activation of NF-κB. NF-κB activation was confirmed by nuclear localization of NF-κB p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-κB signaling attenuated LPS-induced TNFα plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-κB signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-κB does not sensitize GCTs to TRAIL or cisplatin.

TLR4 activates NF-{kappa}B in human ovarian granulosa tumor cells

Energy Technology Data Exchange (ETDEWEB)

Woods, Dori C., E-mail: dwoods2@partners.org [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); White, Yvonne A.R. [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); Dau, Caroline [University of California, San Francisco, School of Dentistry, San Francisco, CA 94143 (United States); Johnson, A.L. [Center for Reproductive Biology and Health, The Pennsylvania State University, University Park, PA 16802 (United States)

2011-06-17

Highlights: {yields} TLR4 is expressed in human ovarian granulosa tumor cells. {yields} Acting through TLR4, LPS and HSP60 induce a NF{kappa}B signaling cascade in human ovarian granulosa tumor cells. {yields} NF{kappa}B activation or inhibition did not alter chemosensitivity to TRAIL or cisplatin. -- Abstract: Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-{kappa}B) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to I{kappa}B degradation and activation of NF-{kappa}B. NF-{kappa}B activation was confirmed by nuclear localization of NF-{kappa}B p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-{kappa}B signaling attenuated LPS-induced TNF{alpha} plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-{kappa}B signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-{kappa}B does not sensitize GCTs to TRAIL or cisplatin.

Toll-like receptor-4 (TLR-4) expression on polymorphonuclear ...

African Journals Online (AJOL)

To establish a foundation for further researches on the improvement of polymorphonuclear neutrophil leukocytes (PMN) functions in dairy cow during perinatal period, the counting of PMN, as well as the mRNA and protein expression of toll-like receptor-4 (TLR-4) on PMN was studied during this critical period.

TLR4 Signaling Pathway Modulators as Potential Therapeutics in Inflammation and Sepsis

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Nikolay N. Kuzmich

2017-10-01

Full Text Available Toll-Like Receptor 4 (TLR4 signal pathway plays an important role in initiating the innate immune response and its activation by bacterial endotoxin is responsible for chronic and acute inflammatory disorders that are becoming more and more frequent in developed countries. Modulation of the TLR4 pathway is a potential strategy to specifically target these pathologies. Among the diseases caused by TLR4 abnormal activation by bacterial endotoxin, sepsis is the most dangerous one because it is a life-threatening acute system inflammatory condition that still lacks specific pharmacological treatment. Here, we review molecules at a preclinical or clinical phase of development, that are active in inhibiting the TLR4-MyD88 and TLR4-TRIF pathways in animal models. These are low-molecular weight compounds of natural and synthetic origin that can be considered leads for drug development. The results of in vivo studies in the sepsis model and the mechanisms of action of drug leads are presented and critically discussed, evidencing the differences in treatment results from rodents to humans.

Elevated muscle TLR4 expression and metabolic endotoxemia in human aging.

Science.gov (United States)

Ghosh, Sangeeta; Lertwattanarak, Raweewan; Garduño, Jose de Jesus; Galeana, Joaquin Joya; Li, Jinqi; Zamarripa, Frank; Lancaster, Jack L; Mohan, Sumathy; Hussey, Sophie; Musi, Nicolas

2015-02-01

Aging is associated with alterations in glucose metabolism and sarcopenia that jointly contribute to a higher risk of developing type 2 diabetes. Because aging is considered as a state of low-grade inflammation, in this study we examined whether older, healthy (lean, community-dwelling) participants have altered signaling flux through toll-like receptor 4 (TLR4), a key mediator of innate and adaptive immune responses. We also examined whether a 4-month aerobic exercise program would have an anti-inflammatory effect by reducing TLR4 expression and signaling. At baseline, muscle TLR4, nuclear factor κB p50 and nuclear factor κB p65 protein content, and c-Jun N-terminal kinase phosphorylation were significantly elevated in older versus young participants. The plasma concentration of the TLR4 agonist lipopolysaccharide and its binding protein also were significantly elevated in older participants, indicative of metabolic endotoxemia, which is a recently described phenomenon of increased plasma endotoxin level in metabolic disease. These alterations in older participants were accompanied by decreased insulin sensitivity, quadriceps muscle volume, and muscle strength. The exercise training program increased insulin sensitivity, without affecting quadriceps muscle volume or strength. Muscle TLR4, nuclear factor κB, and c-Jun N-terminal kinase, and plasma lipopolysaccharide and lipopolysaccharide binding protein were not changed by exercise. In conclusion, insulin resistance and sarcopenia of aging are associated with increased TLR4 expression/signaling, which may be secondary to metabolic endotoxemia. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth

OpenAIRE

Haricharan, Svasti; Brown, Powel

2015-01-01

This study fundamentally alters our understanding of how TLR4 drives breast cancer. Although TLR4 was previously considered a tumor promoter, we demonstrate a complex, TP53-dependent role for TLR4 in regulating tumor growth. TP53 is a tumor suppressor commonly inactivated across cancer types. In TP53 wild-type cancer cells, TLR4 activation causes secretion of IFN-γ into the microenvironment, resulting in induction of p21 and inhibition of cell growth. Conversely, TLR4 activation in TP53 mutan...

Pathogenic strains of Acanthamoeba are recognized by TLR4 and initiated inflammatory responses in the cornea.

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Hassan Alizadeh

Full Text Available Free-living amoebae of the Acanthamoeba species are the causative agent of Acanthamoeba keratitis (AK, a sight-threatening corneal infection that causes severe pain and a characteristic ring-shaped corneal infiltrate. Innate immune responses play an important role in resistance against AK. The aim of this study is to determine if Toll-like receptors (TLRs on corneal epithelial cells are activated by Acanthamoeba, leading to initiation of inflammatory responses in the cornea. Human corneal epithelial (HCE cells constitutively expressed TLR1, TLR2, TLR3, TLR4, and TLR9 mRNA, and A. castellanii upregulated TLR4 transcription. Expression of TLR1, TLR2, TLR3, and TLR9 was unchanged when HCE cells were exposed to A. castellanii. IL-8 mRNA expression was upregulated in HCE cells exposed to A. castellanii. A. castellanii and lipopolysaccharide (LPS induced significant IL-8 production by HCE cells as measured by ELISA. The percentage of total cells positive for TLR4 was higher in A. castellanii stimulated HCE cells compared to unstimulated HCE cells. A. castellanii induced upregulation of IL-8 in TLR4 expressing human embryonic kidney (HEK-293 cells, but not TLR3 expressing HEK-293 cells. TLR4 neutralizing antibody inhibited A. castellanii-induced IL-8 by HCE and HEK-293 cells. Clinical strains but not soil strains of Acanthamoeba activated TLR4 expression in Chinese hamster corneas in vivo and in vitro. Clinical isolates but not soil isolates of Acanthamoeba induced significant (P< 0.05 CXCL2 production in Chinese hamster corneas 3 and 7 days after infection, which coincided with increased inflammatory cells in the corneas. Results suggest that pathogenic species of Acanthamoeba activate TLR4 and induce production of CXCL2 in the Chinese hamster model of AK. TLR4 may be a potential target in the development of novel treatment strategies in Acanthamoeba and other microbial infections that activate TLR4 in corneal cells.

Lipopolysaccharides with acylation defects potentiate TLR4 signaling and shape T cell responses.

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Anna Martirosyan

Full Text Available Lipopolysaccharides or endotoxins are components of Gram-negative enterobacteria that cause septic shock in mammals. However, a LPS carrying hexa-acyl lipid A moieties is highly endotoxic compared to a tetra-acyl LPS and the latter has been considered as an antagonist of hexa-acyl LPS-mediated TLR4 signaling. We investigated the relationship between the structure and the function of bacterial LPS in the context of human and mouse dendritic cell activation. Strikingly, LPS with acylation defects were capable of triggering a strong and early TLR4-dependent DC activation, which in turn led to the activation of the proteasome machinery dampening the pro-inflammatory cytokine secretion. Upon activation with tetra-acyl LPS both mouse and human dendritic cells triggered CD4(+ T and CD8(+ T cell responses and, importantly, human myeloid dendritic cells favored the induction of regulatory T cells. Altogether, our data suggest that LPS acylation controlled by pathogenic bacteria might be an important strategy to subvert adaptive immunity.

TLR2, TLR4 and the MYD88 signaling pathway are crucial for neutrophil migration in acute kidney injury induced by sepsis.

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Angela Castoldi

Full Text Available The aim of this study was to investigate the role of TLR2, TLR4 and MyD88 in sepsis-induced AKI. C57BL/6 TLR2(-/-, TLR4(-/- and MyD88(-/- male mice were subjected to sepsis by cecal ligation and puncture (CLP. Twenty four hours later, kidney tissue and blood samples were collected for analysis. The TLR2(-/-, TLR4(-/- and MyD88(-/- mice that were subjected to CLP had preserved renal morphology, and fewer areas of hypoxia and apoptosis compared with the wild-type C57BL/6 mice (WT. MyD88(-/- mice were completely protected compared with the WT mice. We also observed reduced expression of proinflammatory cytokines in the kidneys of the knockout mice compared with those of the WT mice and subsequent inhibition of increased vascular permeability in the kidneys of the knockout mice. The WT mice had increased GR1(+low cells migration compared with the knockout mice and decreased in GR1(+high cells migration into the peritoneal cavity. The TLR2(-/-, TLR4(-/-, and MyD88(-/- mice had lower neutrophil infiltration in the kidneys. Depletion of neutrophils in the WT mice led to protection of renal function and less inflammation in the kidneys of these mice. Innate immunity participates in polymicrobial sepsis-induced AKI, mainly through the MyD88 pathway, by leading to an increased migration of neutrophils to the kidney, increased production of proinflammatory cytokines, vascular permeability, hypoxia and apoptosis of tubular cells.

Dioscorin isolated from Dioscorea alata activates TLR4-signaling pathways and induces cytokine expression in macrophages.

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Fu, Shu-Ling; Hsu, Ya-Hui; Lee, Pei-Yeh; Hou, Wen-Chi; Hung, Ling-Chien; Lin, Chao-Hsiung; Chen, Chiu-Ming; Huang, Yu-Jing

2006-01-06

The Toll-like receptor 4 (TLR4)-signaling pathway is crucial for activating both innate and adaptive immunity. TLR4 is a promising molecular target for immune-modulating drugs, and TLR4 agonists are of therapeutic potential for treating immune diseases and cancers. Several medicinal herb-derived components have recently been reported to act via TLR4-dependent pathways, suggesting that medicinal plants are potential resources for identifying TLR4 activators. We have applied a screening procedure to systematically identify herbal constituents that activate TLR4. To exclude possible LPS contamination in these plant-derived components, a LPS inhibitor, polymyxin B, was added during screening. One of the plant components we identified from the screening was dioscorin, the glycoprotein isolated from Dioscorea alata. It induced TLR4-downstream cytokine expression in bone marrow cells isolated from TLR4-functional C3H/HeN mice but not from TLR4-defective C3H/HeJ mice. Dioscorin also stimulated multiple signaling molecules (NF-kappaB, ERK, JNK, and p38) and induced the expression of cytokines (TNF-alpha, IL-1beta, and IL-6) in murine RAW 264.7 macrophages. Furthermore, the ERK, p38, JNK, and NF-kappaB-mediated pathways are all involved in dioscorin-mediated TNF-alpha production. In summary, our results demonstrate that dioscorin is a novel TLR4 activator and induces macrophage activation via typical TLR4-signaling pathways.

TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth.

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Haricharan, Svasti; Brown, Powel

2015-06-23

Breast cancer is a leading cause of cancer-related death, and it is important to understand pathways that drive the disease to devise effective therapeutic strategies. Our results show that Toll-like receptor 4 (TLR4) drives breast cancer cell growth differentially based on the presence of TP53, a tumor suppressor. TP53 is mutationally inactivated in most types of cancer and is mutated in 30-50% of diagnosed breast tumors. We demonstrate that TLR4 activation inhibits growth of TP53 wild-type cells, but promotes growth of TP53 mutant breast cancer cells by regulating proliferation. This differential effect is mediated by changes in tumor cell cytokine secretion. Whereas TLR4 activation in TP53 mutant breast cancer cells increases secretion of progrowth cytokines, TLR4 activation in TP53 wild-type breast cancer cells increases type I IFN (IFN-γ) secretion, which is both necessary and sufficient for mediating TLR4-induced growth inhibition. This study identifies a novel dichotomous role for TLR4 as a growth regulator and a modulator of tumor microenvironment in breast tumors. These results have translational relevance, demonstrating that TP53 mutant breast tumor growth can be suppressed by pharmacologic TLR4 inhibition, whereas TLR4 inhibitors may in fact promote growth of TP53 wild-type tumors. Furthermore, using data generated by The Cancer Genome Atlas consortium, we demonstrate that the effect of TP53 mutational status on TLR4 activity may extend to ovarian, colon, and lung cancers, among others, suggesting that the viability of TLR4 as a therapeutic target depends on TP53 status in many different tumor types.

Compound list: amitriptyline [Open TG-GATEs

Lifescience Database Archive (English)

Full Text Available amitriptyline AMT 00070 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/amit...riptyline.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vitro/amit...riptyline.Rat.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Single/amit...edbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/amitriptyline.Rat.in_vivo.Liver.Repeat.zip ...

Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4

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Semeraro, Fabrizio; Ammollo, Concetta T.; Morrissey, James H.; Dale, George L.; Friese, Paul; Esmon, Naomi L.

2011-01-01

The release of histones from dying cells is associated with microvascular thrombosis and, because histones activate platelets, this could represent a possible pathogenic mechanism. In the present study, we assessed the influence of histones on the procoagulant potential of human platelets in platelet-rich plasma (PRP) and in purified systems. Histones dose-dependently enhanced thrombin generation in PRP in the absence of any trigger, as evaluated by calibrated automated thrombinography regardless of whether the contact phase was inhibited. Activation of coagulation required the presence of fully activatable platelets and was not ascribable to platelet tissue factor, whereas targeting polyphosphate with phosphatase reduced thrombin generation even when factor XII (FXII) was blocked or absent. In the presence of histones, purified polyphosphate was able to induce thrombin generation in plasma independently of FXII. In purified systems, histones induced platelet aggregation; P-selectin, phosphatidylserine, and FV/Va expression; and prothrombinase activity. Blocking platelet TLR2 and TLR4 with mAbs reduced the percentage of activated platelets and lowered the amount of thrombin generated in PRP. These data show that histone-activated platelets possess a procoagulant phenotype that drives plasma thrombin generation and suggest that TLR2 and TLR4 mediate the activation process. PMID:21673343

Rationally Designed TLR4 Ligands for Vaccine Adjuvant Discovery

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Kelsey A. Gregg

2017-05-01

Full Text Available Adjuvant properties of bacterial cell wall components like MPLA (monophosphoryl lipid A are well described and have gained FDA approval for use in vaccines such as Cervarix. MPLA is the product of chemically modified lipooligosaccharide (LOS, altered to diminish toxic proinflammatory effects while retaining adequate immunogenicity. Despite the virtually unlimited number of potential sources among bacterial strains, the number of useable compounds within this promising class of adjuvants are few. We have developed bacterial enzymatic combinatorial chemistry (BECC as a method to generate rationally designed, functionally diverse lipid A. BECC removes endogenous or introduces exogenous lipid A-modifying enzymes to bacteria, effectively reprogramming the lipid A biosynthetic pathway. In this study, BECC is applied within an avirulent strain of Yersinia pestis to develop structurally distinct LOS molecules that elicit differential Toll-like receptor 4 (TLR4 activation. Using reporter cell lines that measure NF-κB activation, BECC-derived molecules were screened for the ability to induce a lower proinflammatory response than Escherichia coli LOS. Their structures exhibit varied, dose-dependent, TLR4-driven NF-κB activation with both human and mouse TLR4 complexes. Additional cytokine secretion screening identified molecules that induce levels of tumor necrosis factor alpha (TNF-α and interleukin-8 (IL-8 comparable to the levels induced by phosphorylated hexa-acyl disaccharide (PHAD. The lead candidates demonstrated potent immunostimulation in mouse splenocytes, human primary blood mononuclear cells (PBMCs, and human monocyte-derived dendritic cells (DCs. This newly described system allows directed programming of lipid A synthesis and has the potential to generate a diverse array of TLR4 agonist candidates.

Structure-Activity Relationship in TLR4 Mutations: Atomistic Molecular Dynamics Simulations and Residue Interaction Network Analysis

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Anwar, Muhammad Ayaz; Choi, Sangdun

2017-03-01

Toll-like receptor 4 (TLR4), a vital innate immune receptor present on cell surfaces, initiates a signaling cascade during danger and bacterial intrusion. TLR4 needs to form a stable hexamer complex, which is necessary to dimerize the cytoplasmic domain. However, D299G and T399I polymorphism may abrogate the stability of the complex, leading to compromised TLR4 signaling. Crystallography provides valuable insights into the structural aspects of the TLR4 ectodomain; however, the dynamic behavior of polymorphic TLR4 is still unclear. Here, we employed molecular dynamics simulations (MDS), as well as principal component and residue network analyses, to decipher the structural aspects and signaling propagation associated with mutations in TLR4. The mutated complexes were less cohesive, displayed local and global variation in the secondary structure, and anomalous decay in rotational correlation function. Principal component analysis indicated that the mutated complexes also exhibited distinct low-frequency motions, which may be correlated to the differential behaviors of these TLR4 variants. Moreover, residue interaction networks (RIN) revealed that the mutated TLR4/myeloid differentiation factor (MD) 2 complex may perpetuate abnormal signaling pathways. Cumulatively, the MDS and RIN analyses elucidated the mutant-specific conformational alterations, which may help in deciphering the mechanism of loss-of-function mutations.

Epithelial expression of TLR4 is modulated in COPD and by steroids, salmeterol and cigarette smoke

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Dorscheid Delbert R

2007-11-01

Full Text Available Abstract The toll-like receptors (TLRs are a key component of host defense in the respiratory epithelium. Cigarette smoking is associated with increased susceptibility to infection, while COPD is characterised by bacterial colonisation and infective exacerbations. We found reduced TLR4 gene expression in the nasal epithelium of smokers compared with non-smoking controls, while TLR2 expression was unchanged. Severe COPD was associated with reduced TLR4 expression compared to less severe disease, with good correlation between nasal and tracheal expression. We went on to examine the effect of potential modulators of TLR4 expression in respiratory epithelium pertinent to airways disease. Using an airway epithelial cell line, we found a dose-dependent downregulation in TLR4 mRNA and protein expression by stimulation with cigarette smoke extracts. Treatment with the corticosteroids fluticasone and dexamethasone resulted in a dose-dependent reduction in TLR4 mRNA and protein. The functional significance of this effect was demonstrated by impaired IL-8 and HBD2 induction in response to LPS. Stimulation with salmeterol (10-6 M caused upregulation of TLR4 membrane protein presentation with no upregulation of mRNA, suggesting a post-translational effect. The effect of dexamethasone and salmeterol in combination was additive, with downregulation of TLR4 gene expression, and no change in membrane receptor expression. Modulation of TLR4 in respiratory epithelium may have important implications for airway inflammation and infection in response to inhaled pathogens.

Combined paracetamol and amitriptyline adsorption to activated charcoal

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Hoegberg, Lotte Christine Groth; Groenlykke, Thor Buch; Abildtrup, Ulla

2010-01-01

Objectives. High-gram drug doses seen in multiple-drug poisonings might be close to the adsorption capacity of activated charcoal (AC). The aim was to determine the maximum adsorption capacities (Q(m)) of amitriptyline and paracetamol, separately and in combination, to AC. Methods. ACs (Carbomix......® and Norit Ready-To-Use) were tested in vitro. At pH 1.2 and pH 7.2, 0.250 g AC and paracetamol and/or amitriptyline were mixed and incubated. The AC: drug ratios were 10:1, 5:1, 3:1, 2:1, and 1:1. The mixed-drug adsorption vials contained the same AC: paracetamol ratios, but amitriptyline was added as fixed...... dose (0.080 g) to all samples. Drug concentrations in the liquid phase were analyzed using high-performance liquid chromatography (HPLC)/UV-detection. Results. Q(m), amitriptyline, were 0.49 g/g Carbomix® and 0.70 g/g Norit Ready-To-Use, and Q(m), paracetamol, were 0.63 g/g Carbomix® and 0.72 g/g Norit...

Amitriptyline versus placebo for major depression

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Kessing, Lars Vedel; Bukh, Jens Otto Drachmann

2013-01-01

A recent Cochrane review concluded that amitriptyline is an efficacious antidepressant drug, however associated with a number of side effects. The present paper discusses this finding in relation to studies on effects and side effects of SSRIs and dual-action drugs. It is concluded that there is ......A recent Cochrane review concluded that amitriptyline is an efficacious antidepressant drug, however associated with a number of side effects. The present paper discusses this finding in relation to studies on effects and side effects of SSRIs and dual-action drugs. It is concluded...

A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells

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Schnabl, Bernd; Brandl, Katharina; Fink, Marina; Gross, Philipp; Taura, Kojiro; Gaebele, Erwin; Hellerbrand, Claus; Falk, Werner

2008-01-01

Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NFκB and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo

Telomere-mediated chromosomal instability triggers TLR4 induced inflammation and death in mice.

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Rabindra N Bhattacharjee

Full Text Available BACKGROUND: Telomeres are essential to maintain chromosomal stability. Cells derived from mice lacking telomerase RNA component (mTERC-/- mice display elevated telomere-mediated chromosome instability. Age-dependent telomere shortening and associated chromosome instability reduce the capacity to respond to cellular stress occurring during inflammation and cancer. Inflammation is one of the important risk factors in cancer progression. Controlled innate immune responses mediated by Toll-like receptors (TLR are required for host defense against infection. Our aim was to understand the role of chromosome/genome instability in the initiation and maintenance of inflammation. METHODOLOGY/PRINCIPAL FINDINGS: We examined the function of TLR4 in telomerase deficient mTERC-/- mice harbouring chromosome instability which did not develop any overt immunological disorder in pathogen-free condition or any form of cancers at this stage. Chromosome instability was measured in metaphase spreads prepared from wildtype (mTERC+/+, mTERC+/- and mTERC-/- mouse splenocytes. Peritoneal and/or bone marrow-derived macrophages were used to examine the responses of TLR4 by their ability to produce inflammatory mediators TNFalpha and IL6. Our results demonstrate that TLR4 is highly up-regulated in the immune cells derived from telomerase-null (mTERC-/- mice and lipopolysaccharide, a natural ligand for TLR4 stabilises NF-kappaB binding to its promoter by down-regulating ATF-3 in mTERC-/- macrophages. CONCLUSIONS/SIGNIFICANCE: Our findings implied that background chromosome instability in the cellular level stabilises the action of TLR4-induced NF-kappaB action and sensitises cells to produce excess pro-inflammatory mediators. Chromosome/genomic instability data raises optimism for controlling inflammation by non-toxic TLR antagonists among high-risk groups.

Altered Expression of TLR2 and TLR4 on Peripheral CD14+ Blood Monocytes in Children with Urinary Tract Infection.

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Karananou, Panagiota; Fleva, Alexandra; Tramma, Despoina; Alataki, Anastasia; Pavlitou-Tsiontsi, Aikaterini; Emporiadou-Peticopoulou, Maria; Papadopoulou-Alataki, Efimia

2016-01-01

Urinary tract infection (UTI) is the second most common bacterial infection, after otitis media, in infants and children. The mechanisms of disease susceptibility and the role of immunity in the pathogenesis of UTI in children have been evaluated. In recent years, Toll-Like Receptors (TLRs) have been recognized as specific components of the innate immune system constituting important mediators in host immune recognition. The aim of the present study was to determine ΤLR2 and TLR4 expression during the acute phase of UTI in infants and children by measuring the CD14/TLR2 and CD14/TLR4 expression on monocytes. We also attempted to compare the TLRs expression with the immunological status of the patients to healthy children. The study group consisted of 60 children (36 females and 24 males) and the control group included 60 age-matched pediatric subjects (27 females and 33 males). In our study, no antibody deficiency was found either in the children with UTI or in healthy subjects. There might be a connection between low IgA, IgG, and IgG subclasses serum levels and UTI as there was a statistically significant difference between patients and healthy children. A higher expression of CD14/TLR2 was revealed in patients (90,07%) compared to controls (85,48%) as well as CD14/TLR4 in patients (90,53%) compared to controls (87,25%) (statistically significant difference, p UTIs' pathogenesis in children.

Heme activates TLR4-mediated inflammatory injury via MyD88/TRIF signaling pathway in intracerebral hemorrhage

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Lin Sen

2012-03-01

Full Text Available Abstract Background Inflammatory injury plays a critical role in intracerebral hemorrhage (ICH-induced neurological deficits; however, the signaling pathways are not apparent by which the upstream cellular events trigger innate immune and inflammatory responses that contribute to neurological impairments. Toll-like receptor 4 (TLR4 plays a role in inflammatory damage caused by brain disorders. Methods In this study, we investigate the role of TLR4 signaling in ICH-induced inflammation. In the ICH model, a significant upregulation of TLR4 expression in reactive microglia has been demonstrated using real-time RT-PCR. Activation of microglia was detected by immunohistochemistry, cytokines were measured by ELISA, MyD88, TRIF and NF-κB were measured by Western blot and EMSA, animal behavior was evaluated by animal behavioristics. Results Compared to WT mice, TLR4−/− mice had restrained ICH-induced brain damage showing in reduced cerebral edema and lower neurological deficit scores. Quantification of cytokines including IL-6, TNF-α and IL-1β and assessment of macrophage infiltration in perihematoma tissues from TLR4−/−, MyD88−/− and TRIF−/− mice showed attenuated inflammatory damage after ICH. TLR4−/− mice also exhibited reduced MyD88 and TRIF expression which was accompanied by decreased NF-κB activity. This suggests that after ICH both MyD88 and TRIF pathways might be involved in TLR4-mediated inflammatory injury possibly via NF-κB activation. Exogenous hemin administration significantly increased TLR4 expression and microglial activation in cultures and also exacerbated brain injury in WT mice but not in TLR4−/− mice. Anti-TLR4 antibody administration suppressed hemin-induced microglial activation in cultures and in the mice model of ICH. Conclusions Our findings suggest that heme potentiates microglial activation via TLR4, in turn inducing NF-κB activation via the MyD88/TRIF signaling pathway, and ultimately

Palmitate induces VSMC apoptosis via toll like receptor (TLR)4/ROS/p53 pathway.

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Zhang, Yuanjun; Xia, Guanghao; Zhang, Yaqiong; Liu, Juxiang; Liu, Xiaowei; Li, Weihua; Lv, Yaya; Wei, Suhong; Liu, Jing; Quan, Jinxing

2017-08-01

Toll-like receptor 4 (TLR4) has been implicated in vascular inflammation, as well as in the pathogenesis of atherosclerosis and diabetes. Vascular smooth muscle cell (VSMC) apoptosis has been shown to induce plaque vulnerability in atherosclerosis. Previous studies reported that palmitate induced apoptosis in VSMCs; however, the role of TLR4 in palmitate-induced apoptosis in VSMCs has not yet been defined. In this study, we investigated whether or not palmitate-induced apoptosis depended on the activation of the TLR4 pathway. VSMCs were treated with or without palmitate, CRISPR/Cas9z-mediated genome editing methods were used to deplete TLR4 expression, while NADPH oxidase inhibitors were used to inhibit reactive oxygen species (ROS) generation. Cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, ROS was measured using the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) method, the mRNA and protein expression levels of caspase 3, caspase 9, BCL-2 and p53 were studied by real-time polymerase chain reaction (RT-PCR) and ELISA. Palmitate significantly promotes VSMC apoptosis, ROS generation, and expression of caspase 3, caspase 9 and p53; while NADPH oxidase inhibitor pretreatment markedly attenuated these effects. Moreover, knockdown of TLR4 significantly blocked palmitate-induced ROS generation and VSMC apoptosis accompanied by inhibition of caspase 3, caspase 9, p53 expression and restoration of BCL-2 expression. Our results suggest that palmitate-induced apoptosis depends on the activation of the TLR4/ROS/p53 signaling pathway, and that TLR4 may be a potential therapeutic target for the prevention and treatment of atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

TLR4 Asp299Gly polymorphism may be protective against chronic periodontitis.

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Sellers, R M; Payne, J B; Yu, F; LeVan, T D; Walker, C; Mikuls, T R

2016-04-01

Periodontitis results from interplay between genetic and environmental factors. Single nucleotide polymorphisms (SNPs) in the coding region of the toll-like receptor 4 gene (TLR4) may be associated with periodontitis, although previous studies have been inconclusive. Moreover, the interaction between environmental factors, such as cigarette smoking (a major risk factor for periodontitis), and Porphyromonas gingivalis (a major periodontal pathogen) with the TLR4 coding region Asp299Gly SNP (rs4986790; a SNP associated with lipopolysaccharide-mediated inflammatory responses in periodontitis), have been largely ignored in previous reports. Therefore, the objective of this study was to examine the association between TLR4 Asp299Gly (rs4986790) with alveolar bone height loss (ABHL) and periodontitis, accounting for interactions between this SNP with smoking and P. gingivalis prevalence. The CD14/-260 SNP (rs2569190) served as a control, as a recent meta-analysis suggested no relationship between this SNP and periodontitis. This multicenter study included 617 participants who had rheumatoid arthritis or osteoarthritis. This report presents a secondary outcome from the primary case-control study examining the relationship of periodontitis with established rheumatoid arthritis. The Centers for Disease Control/American Academy of Periodontology case definitions of periodontitis were used for this analysis. Participants received a full-mouth clinical periodontal examination and panoramic radiograph. Percentage ABHL was measured on posterior teeth. The TLR4 Asp299Gly and CD14/-260 SNPs were selected a priori and genotypes were determined using the ImmunoChip array (Illumina(®) ). Minor allele frequencies and associations with periodontitis and ABHL did not differ according to rheumatoid arthritis vs. osteoarthritis status; therefore, data from these two groups were pooled. The presence of P. gingivalis was detected in subgingival plaque by PCR. Multivariate ordinal

Repeated administration of amitriptyline reduces oxaliplatin-induced mechanical allodynia in rats.

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Sada, Hikaru; Egashira, Nobuaki; Ushio, Soichiro; Kawashiri, Takehiro; Shirahama, Masafumi; Oishi, Ryozo

2012-01-01

Oxaliplatin is a key drug in the treatment of colorectal cancer, but it causes acute and chronic neuropathies in patients. Amitriptyline has widely been used in patients with painful neuropathy. In this study, we investigated the effect of amitriptyline on the oxaliplatin-induced neuropathy in rats. Repeated administration of amitriptyline (5 and 10 mg/kg, p.o., once a day) reduced the oxaliplatin-induced mechanical allodynia but not cold hyperalgesia and reversed the oxaliplatin-induced increase in the expression of NR2B protein and mRNA in rat spinal cord. These results suggest that amitriptyline is useful for the treatment of oxaliplatin-induced neuropathy clinically.

Amitriptyline for the treatment of fibromyalgia: a comprehensive review.

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Rico-Villademoros, Fernando; Slim, Mahmoud; Calandre, Elena P

2015-10-01

Fibromyalgia is characterized by chronic generalized pain accompanied by a wide range of clinical manifestations. Most clinical practice guidelines recommend multidisciplinary treatment using a combination of pharmacological and non-pharmacological therapies. The tricyclic antidepressant amitriptyline has been most thoroughly studied in fibromyalgia. Amitriptyline has been evaluated in placebo-controlled studies, and it has served as an active comparator to other therapeutic interventions in the treatment of fibromyalgia. In addition, several systematic reviews and meta-analyses have evaluated its efficacy and safety for the treatment of fibromyalgia. Data from individual studies as well as from systematic reviews indicate that low doses (10-75 mg/day) of amitriptyline are effective for the treatment of fibromyalgia and, despite the limited quality of the data, they do not seem to be associated with relevant tolerability or safety issues. Consistent with some clinical guidelines, we believe amitriptyline in low doses should be considered a first-line drug for the treatment of fibromyalgia.

TLR4 Expression Is Associated with Left Ventricular Dysfunction in Patients Undergoing Coronary Artery Bypass Surgery.

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Orna Avlas

Full Text Available Toll-like receptor 4 (TLR4 is an innate immune receptor expressed in immune cells and the heart. Activation of the immune system following myocardial ischemia causes the release of proinflammatory mediators that may negatively influence heart function.The aim of this study is to determine whether TLR4 is activated in peripheral monocytes and heart tissue taken from patients with varying degrees of myocardial dysfunction caused by coronary artery diseases and scheduled for coronary artery bypass graft (CABG surgery before 12 months following operation.Patients (n = 44 undergoing CABG surgery having left ventricular ejection fraction ≤ 45% ('reduced EF', n = 20 were compared to patients with preserved EF >45% ('preserved EF' group, n = 24. 'Reduced EF' patients exhibited increased TLR4 expression in monocytes (2.78±0.49 vs. 1.76±0.07 rMFI, p = 0.03. Plasma levels of C-reactive protein, microRNA miR-320a, brain natriuretic peptide (pro BNP and NADPH oxidase (NOX4 were also significantly different between the 'preserved EF' and 'reduced EF'groups. Elevated TLR4 gene expression levels in the right auricle correlated with those of EF (p<0.008, NOX4 (p<0.008 and miR320, (p<0.04. In contrast, no differences were observed in peripheral monocyte TLR2 expression. After CABG surgery, monocyte TLR4 expression decreased in all patients, reaching statistical significance in the 'reduced EF' group.TLR4 is activated in peripheral monocytes and heart tissue obtained from patients with ischemic heart disease and reduced left ventricular function. Coronary revascularization decreases TLR4 expression. We therefore propose that TLR4 plays a pathogenic role and may serve as an additional marker of ischemic myocardial dysfunction.

Expression of TLR-2, TLR-4, NOD2 and pNF-kappaB in a neonatal rat model of necrotizing enterocolitis.

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Aurelie Le Mandat Schultz

Full Text Available BACKGROUND: The etiology of necrotizing enterocolitis (NEC results from a combination of several risk factors that act synergistically and occurs in the same circumstances as those which lead to innate immunity activation. Pattern recognition molecules could be an important player in the initiation of an exaggerated inflammatory response leading to intestinal injury in NEC. METHODOLOGY/PRINCIPAL FINDINGS: We specifically evaluated intestinal epithelial cell (IEC expression of Toll-like receptor 2 (TLR-2, TLR-4, NOD2 and phosphorylated NF-kappaB (pNF-kappaB after mucosal injury in a rat model of NEC induced by prematurity, systemic hypoxia, and a rich protein formula. In the control group (group 1, neonatal rats were full-term and breast-fed; in the experimental groups, rat pups were preterm at day 21 of gestation and rat-milk fed (group 2 or hand-gavaged with a protein rich formula after a hypoxia-reoxygenation procedure (group 3. Morphological mucosal changes in the small bowel were scored on hematoxylin- and eosin-stained sections. Immunohistochemistry was performed on frozen tissue sections using anti TLR-2 and active pNF-kappaB p65 antibodies. Real-time RT-PCR was performed to assess mRNA expression of NOD2, TLR-2 and TLR-4. Proliferation and apoptosis were studied in paraffin sections using anti Ki-67 and caspase-3 antibodies, respectively. The combination of immaturity, protein rich formula and a hypoxia-reoxygenation procedure induces pathological mucosal damage consistent with NEC. There was an overexpression of TLR-2, and pNF-kappaB in IECs that was correlated with the severity of mucosal damage, together with an increase of apoptotic IECs and markedly impaired proliferation. In addition, these immunological alterations appeared before severe mucosal damage. TLR-2 mRNA were also increased in NEC together with TLR-4 mRNA using real-time RT-PCR whereas NOD2 expression was unchanged. CONCLUSIONS/SIGNIFICANCE: These results show that this

Increased TLR4 expression in murine placentas after oral infection with periodontal pathogens

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Arce, R.M.; Barros, S.P.; Wacker, B.; Peters, B.; Moss, K.; Offenbacher, S.

2009-01-01

Maternal periodontitis has emerged as a putative risk factor for preterm births in humans. The periodontitis-associated dental biofilm is thought to serve as an important source of oral bacteria and related virulence factors that hematogenously disseminate and affect the fetoplacental unit; however the underlying biological mechanisms are yet to be fully elucidated. This study hypothesized that an oral infection with the human periodontal pathogens Campylobacter rectus and Porphyromonas gingivalis is able to induce fetal growth restriction, placental inflammation and enhance Toll-like receptors type 4 (TLR4) expression in a murine pregnancy model. Female Balb/C mice (n=40) were orally infected with C. rectus and/or P. gingivalis over a 16-week period and mated once per week. Pregnant mice were sacrificed at embryonic day (E) 16.5 and placentas were collected and analyzed for TLR4 mRNA levels and qualitative protein expression by real time PCR and immunofluorescence. TLR4 mRNA expression was found to be increased in C. rectus-infected group (1.98±0.886 fold difference, Pperiodontal pathogens. The TLR4 pathway has been implicated in the pathogenesis of preterm births; therefore the abnormal regulation of placental TLR4 may give new insights into how maternal periodontitis and periodontal pathogens might be linked to placental inflammation and preterm birth pathogenesis. PMID:19101032

Hyaluronan signaling during ozone-induced lung injury requires TLR4, MyD88, and TIRAP.

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Zhuowei Li

Full Text Available Ozone exposure is associated with exacerbation of reactive airways disease. We have previously reported that the damage-associated molecular pattern, hyaluronan, is required for the complete biological response to ambient ozone and that hyaluronan fragments signal through toll-like receptor 4 (TLR4. In this study, we further investigated the role of TLR4 adaptors in ozone-induced airway hyperresponsiveness (AHR and the direct response to hyaluronan fragments (HA. Using a murine model of AHR, C57BL/6J, TLR4-/-, MyD88-/-, and TIRAP-/- mice were characterized for AHR after exposure to either ozone (1 ppm × 3 h or HA fragments. Animals were characterized for AHR with methacholine challenge, cellular inflammation, lung injury, and production of pro-inflammatory cytokines. Ozone-exposed C57BL/6J mice developed cellular inflammation, lung injury, pro-inflammatory cytokines, and AHR, while mice deficient in TLR4, MyD88 or TIRAP demonstrated both reduced AHR and reduced levels of pro-inflammatory cytokines including TNFα, IL-1β, MCP-1, IL-6 and KC. The level of hyaluronan was increased after inhalation of ozone in each strain of mice. Direct challenge of mice to hyaluronan resulted in AHR in C57BL/6J mice, but not in TLR4-/-, MyD88-/-, or TIRAP-/- mice. HA-induced cytokine production in wild-type mice was significantly reduced in TLR4-/-, MyD88-/-, or TIRAP-/- mice. In conclusion, our findings support that ozone-induced airway hyperresponsiveness is dependent on the HA-TLR4-MyD88-TIRAP signaling pathway.

Effectiveness of amitriptyline for treating functional dyspepsia in adolescents

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Indra Mustawa

2017-01-01

Full Text Available Background Functional dyspepsia is common among adolescents. Pain reduces children’s quality of life, psychosocial functioning, and school attendance. Amitriptyline is assumed to be one of the alternative treatments in functional dyspepsia. Objective To investigate the effectiveness of amytriptyline as a treatment  for  functional dyspepsia in adolescents. Methods We conducted a randomized, single-blind, controlled trial from January to March 2011 in junior and senior high school students in Dobo City, Aru Island District, Maluku Province. Adolescents suffering from functional dyspepsia and who fulfilled the inclusion criteria were eligible for the study. Subjects were randomized into two groups. Each group received 10 mg (for body weight < 35 kg or 20 mg (for body weight ≥ 35 kg amitriptyline or placebo once per day for 28 days. Pain frequency was measured in terms of abdominal pain episodes per month, and duration was measured in minutes. Data were analyzed using t-test. Results Eighty-eight students participated in this study: the amitriptyline group (43 subjects and the placebo group (45 subjects. There were no statistically significant differences between the amitriptyline and placebo groups in frequency (P=0.777; 95%CI -0.846 to 1.129 or duration (P=0.728 of abdominal pain after treatment. Conclusion  Amitriptyline is not more effective than placebo for treating functional dyspepsia in adolescents.

Can the TLR-4-Mediated Signaling Pathway Be “A Key Inflammatory Promoter for Sporadic TAA”?

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Giovanni Ruvolo

2014-01-01

Full Text Available Thoracic aorta shows with advancing age various changes and a progressive deterioration in structure and function. As a result, vascular remodeling (VR and medial degeneration (MD occur as pathological entities responsible principally for the sporadic TAA onset. Little is known about their genetic, molecular, and cellular mechanisms. Recent evidence is proposing the strong role of a chronic immune/inflammatory process in their evocation and progression. Thus, we evaluated the potential role of Toll like receptor- (TLR- 4-mediated signaling pathway and its polymorphisms in sporadic TAA. Genetic, immunohistochemical, and biochemical analyses were assessed. Interestingly, the rs4986790 TLR4 polymorphism confers a higher susceptibility for sporadic TAA (OR=14.4, P=0.0008 and it represents, together with rs1799752 ACE, rs3918242 MMP-9, and rs2285053 MMP-2 SNPs, an independent sporadic TAA risk factor. In consistency with these data, a significant association was observed between their combined risk genotype and sporadic TAA. Cases bearing this risk genotype showed higher systemic inflammatory mediator levels, significant inflammatory/immune infiltrate, a typical MD phenotype, lower telomere length, and positive correlations with histopatological abnormalities, hypertension, smoking, and ageing. Thus, TLR4 pathway should seem to have a key role in sporadic TAA. It might represent a potential useful tool for preventing and monitoring sporadic TAA and developing personalized treatments.

TLR4 endogenous ligand MRP8/14 level in enthesitis-related arthritis and its association with disease activity and TLR4 expression.

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Rahman, Mujeeb T; Myles, Arpita; Gaur, Priyanka; Misra, Ramnath; Aggarwal, Amita

2014-02-01

Enthesitis-related arthritis (ERA) is an inflammatory disease of childhood that lacks autoantibodies. Overexpression of surface-expressed Toll-like receptors (TLRs) has been found in ERA. Myeloid-related proteins (MRPs) 8 and 14 are calcium binding proteins that act as an endogenous ligand of TLR4. MRP8/14 levels are elevated in patients with systemic-onset arthritis. Thus we studied the role of MRP8/14 in ERA. The study enrolled patients with ERA. Plasma and SF levels of MRP8/14 were measured by ELISA and TLR4 expression on peripheral blood and SF monocytes was measured by two-colour flow cytometry. Control plasma samples were collected from 48 blood bank donors. Of the 69 patients, 67 were male, with a mean age of 15.2 (s.d. 2.7) years and a disease duration of 5 (s.d. 3) years. Median plasma levels of MRP8/14 were higher in patients (10 862.3 ng/ml) than controls (4426.1 ng/ml, P < 0.0001). Patients with active disease (11 669.5 ng/ml) had higher levels as compared with inactive disease (4421.8 ng/ml, P < 0.0001). Plasma MRP8/14 levels decreased on follow-up after 3 months only in patients who responded to treatment (P = 0.012). MRP8/14 levels were negatively correlated with the frequency of CD14(+)TLR4(+) cells (r = -0.372, P = 0.02). MRP8/14 levels were higher in SF as compared with plasma (15 858.45 ng/ml, P = 0.024). The frequency of CD14(+)TLR4(+) cells was higher in SF as compared with peripheral blood. MRP8/14 levels are increased in the plasma of ERA patients and are higher in those with active disease and the levels decrease in patients who respond to treatment, suggesting that it may be a good biomarker during follow-up.

TLR4 links podocytes with the innate immune system to mediate glomerular injury

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Banas, Miriam C; Banas, Bernhard; Hudkins, Kelly L

2008-01-01

profile of chemokines. In conclusion, it was demonstrated that TLR4 is constitutively expressed by podocytes and is upregulated in MPGN, where it may mediate glomerular injury by modulating expression of chemokines; therefore, TLR4 may link podocytes with the innate immune system to mediate MPGN triggered...... by the deposition of immune complexes....

Lipopolysaccharide induces proliferation and osteogenic differentiation of adipose-derived mesenchymal stromal cells in vitro via TLR4 activation

Energy Technology Data Exchange (ETDEWEB)

Herzmann, Nicole; Salamon, Achim [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany); Fiedler, Tomas [Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Schillingallee 70, D-18057 Rostock (Germany); Peters, Kirsten, E-mail: kirsten.peters@med.uni-rostock.de [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany)

2017-01-01

Multipotent mesenchymal stromal cells (MSC) are capable of multi-lineage differentiation and support regenerative processes. In bacterial infections, resident MSC can come intocontact with and need to react to bacterial components. Lipopolysaccharide (LPS), a typical structure of Gram-negative bacteria, increases the proliferation and osteogenic differentiation of MSC. LPS is usually recognized by the toll-like receptor (TLR) 4 and induces pro-inflammatory reactions in numerous cell types. In this study, we quantified the protein expression of TLR4 and CD14 on adipose-derived MSC (adMSC) in osteogenic differentiation and investigated the effect of TLR4 activation by LPS on NF-κB activation, proliferation and osteogenic differentiation of adMSC. We found that TLR4 is expressed on adMSC whereas CD14 is not, and that osteogenic differentiation induced an increase of the amount of TLR4 protein whereas LPS stimulation did not. Moreover, we could show that NF-κB activation via TLR4 occurs upon LPS treatment. Furthermore, we were able to show that competitive inhibition of TLR4 completely abolished the stimulatory effect of LPS on the proliferation and osteogenic differentiation of adMSC. In addition, the inhibition of TLR4 leads to the complete absence of osteogenic differentiation of adMSC, even when osteogenically stimulated. Thus, we conclude that LPS induces proliferation and osteogenic differentiation of adMSC in vitro through the activation of TLR4 and that the TLR4 receptor seems to play a role during osteogenic differentiation of adMSC.

LPS Promotes Vascular Smooth Muscle Cells Proliferation Through the TLR4/Rac1/Akt Signalling Pathway

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Qianran Yin

2017-12-01

Full Text Available Background/Aims: Lipopolysaccharide (LPS is a potent activator of vascular smooth muscle cells (VSMCs proliferation, but the underlying mechanism remains unknown. In this study, we knocked down Toll-like receptor 4 (TLR4 and Ras-related C3 botulinum toxin substrate 1 (Rac1 expression using small interfering RNA (siRNA in order to investigate the effects and possible mechanisms of LPS-induced VSMCs proliferation. Methods: VSMCs proliferation was monitored by 5-ethynyl-2’-deoxyuridine staining, and Rac1 activity was measured via Glutathione S-transferase pull-down assay. mRNAs encoding proliferating cell nuclear antigen (PCNA, smooth muscle 22α (SM22α, myosin heavy chain (MYH and transient receptor potential channel 1 (TRPC1 were detected by qRT-PCR. The expression of total Akt, p-Akt (308, p-Akt (473, SM22α, MYH and TRPC1 protein was analysed by Western blot. Results: Treatment with TLR4 siRNA (siTLR4 or Rac1 siRNA (siRac1 significantly decreased LPS-induced VSMCs proliferation. Moreover, LPS-induced activation of Rac1 through TLR4 was observed. Western blot analysis revealed that transfection with siTLR4 or siRac1 inhibited LPS-induced Akt phosphorylation. We discovered that LPS stimulated VSMCs proliferation via phenotypic modulation and that this effect was partially inhibited by pre-treatment with siTLR4 or siRac1. Further, TLR4 and Rac1 are involved in LPS-induced activation of TRPC1. Conclusion: This study suggests that LPS exerts an effect on VSMCs proliferation and that the TLR4/Rac1/Akt signalling pathway mediates this effect.

PARTICIPATION OF TLR4 IN ENGULFMENT OF ESCHERICHIA COLI BY HUMAN BLOOD NEUTROPHILS IN PRESENCE OF LIPOPOLYSACCHARIDES

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S. V. Zubova

2012-01-01

Full Text Available Abstract. TLR4 is a key player in signaling system of host cells. Possible role of TLR4 is actively discussed, e.g. its significance for phagocytosis. A capacity of neutrophils to engulf FITC-labeled E. coli bacteria upon activation with LPS of different origin was studied in presence of anti-TLR4 Mab’s (HTA125 clone. It was shown that, in whole blood, TLR4 does not play any essential role in engulfment of bacteria by the neutrophils. Phagocytic activity of neutrophils in blood increases increased after their priming with E. coli endotoxins. LPS from Rb. сapsulatus did not affect phagocytosis. In presence of endotoxins, the degree of TLR4 involvement in neutrophil phagocytosis depends on LPS structure.

The effect of anti-depressant Amitriptyline on the immune system

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Dukan J

1994-04-01

Full Text Available We have studied the effect of amitriptyline, a tricyclic anti-depressant drug on several immune parameters of the Balb/c mice in order to evaluate its immunomodulatory effects. Results showed that amitriptyline will potentiates all of the immunocytes functions except for the production of PGE2 by LPS stimulated monocytes. We have also showed that amitriptyline can normalize the immunosuppressive effect of dexamethasone on mice (experimental stress. These results suggest that one of the mechanisms of action of the tricyclic anti-depressant drugs might be through the modulation of the immune system which has been suppressed by stress or distress

Cigarette smoke regulates the expression of TLR4 and IL-8 production by human macrophages

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Rahman Irfan

2009-05-01

Full Text Available Abstract Background Toll-like receptors (TLRs are present on monocytes and alveolar macrophages that form the first line of defense against inhaled particles. The importance of those cells in the pathophysiology of chronic obstructive pulmonary disease (COPD has well been documented. Cigarette smoke contains high concentration of oxidants which can stimulate immune cells to produce reactive oxygen species, cytokines and chemokines. Methods In this study, we evaluated the effects of cigarette smoke medium (CSM on TLR4 expression and interleukin (IL-8 production by human macrophages investigating the involvement of ROS. Results and Discussion TLR4 surface expression was downregulated on short term exposure (1 h of CSM. The downregulation could be explained by internalization of the TLR4 and the upregulation by an increase in TLR4 mRNA. IL-8 mRNA and protein were also increased by CSM. CSM stimulation increased intracellular ROS-production and decreased glutathione (GSH levels. The modulation of TLR4 mRNA and surface receptors expression, IRAK activation, IκB-α degradation, IL-8 mRNA and protein, GSH depletion and ROS production were all prevented by antioxidants such as N-acetyl-L-cysteine (NAC. Conclusion TLR4 may be involved in the pathogenesis of lung emphysema and oxidative stress and seems to be a crucial contributor in lung inflammation.

Humanized TLR4/MD-2 mice reveal LPS recognition differentially impacts susceptibility to Yersinia pestis and Salmonella enterica.

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Adeline M Hajjar

Full Text Available Although lipopolysaccharide (LPS stimulation through the Toll-like receptor (TLR-4/MD-2 receptor complex activates host defense against Gram-negative bacterial pathogens, how species-specific differences in LPS recognition impact host defense remains undefined. Herein, we establish how temperature dependent shifts in the lipid A of Yersinia pestis LPS that differentially impact recognition by mouse versus human TLR4/MD-2 dictate infection susceptibility. When grown at 37°C, Y. pestis LPS is hypo-acylated and less stimulatory to human compared with murine TLR4/MD-2. By contrast, when grown at reduced temperatures, Y. pestis LPS is more acylated, and stimulates cells equally via human and mouse TLR4/MD-2. To investigate how these temperature dependent shifts in LPS impact infection susceptibility, transgenic mice expressing human rather than mouse TLR4/MD-2 were generated. We found the increased susceptibility to Y. pestis for "humanized" TLR4/MD-2 mice directly paralleled blunted inflammatory cytokine production in response to stimulation with purified LPS. By contrast, for other Gram-negative pathogens with highly acylated lipid A including Salmonella enterica or Escherichia coli, infection susceptibility and the response after stimulation with LPS were indistinguishable between mice expressing human or mouse TLR4/MD-2. Thus, Y. pestis exploits temperature-dependent shifts in LPS acylation to selectively evade recognition by human TLR4/MD-2 uncovered with "humanized" TLR4/MD-2 transgenic mice.

Humanized TLR4/MD-2 mice reveal LPS recognition differentially impacts susceptibility to Yersinia pestis and Salmonella enterica.

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Hajjar, Adeline M; Ernst, Robert K; Fortuno, Edgardo S; Brasfield, Alicia S; Yam, Cathy S; Newlon, Lindsay A; Kollmann, Tobias R; Miller, Samuel I; Wilson, Christopher B

2012-01-01

Although lipopolysaccharide (LPS) stimulation through the Toll-like receptor (TLR)-4/MD-2 receptor complex activates host defense against Gram-negative bacterial pathogens, how species-specific differences in LPS recognition impact host defense remains undefined. Herein, we establish how temperature dependent shifts in the lipid A of Yersinia pestis LPS that differentially impact recognition by mouse versus human TLR4/MD-2 dictate infection susceptibility. When grown at 37°C, Y. pestis LPS is hypo-acylated and less stimulatory to human compared with murine TLR4/MD-2. By contrast, when grown at reduced temperatures, Y. pestis LPS is more acylated, and stimulates cells equally via human and mouse TLR4/MD-2. To investigate how these temperature dependent shifts in LPS impact infection susceptibility, transgenic mice expressing human rather than mouse TLR4/MD-2 were generated. We found the increased susceptibility to Y. pestis for "humanized" TLR4/MD-2 mice directly paralleled blunted inflammatory cytokine production in response to stimulation with purified LPS. By contrast, for other Gram-negative pathogens with highly acylated lipid A including Salmonella enterica or Escherichia coli, infection susceptibility and the response after stimulation with LPS were indistinguishable between mice expressing human or mouse TLR4/MD-2. Thus, Y. pestis exploits temperature-dependent shifts in LPS acylation to selectively evade recognition by human TLR4/MD-2 uncovered with "humanized" TLR4/MD-2 transgenic mice.

Role of TLR4 in the Modulation of Central Amygdala GABA Transmission by CRF Following Restraint Stress.

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Varodayan, F P; Khom, S; Patel, R R; Steinman, M Q; Hedges, D M; Oleata, C S; Homanics, G E; Roberto, M; Bajo, M

2018-01-04

Stress induces neuroimmune responses via Toll-like receptor 4 (TLR4) activation. Here, we investigated the role of TLR4 in the effects of the stress peptide corticotropin-releasing factor (CRF) on GABAergic transmission in the central nucleus of the amygdala (CeA) following restraint stress. Tlr4 knock out (KO) and wild-type rats were exposed to no stress (naïve), a single restraint stress (1 h) or repeated restraint stress (1 h per day for 3 consecutive days). After 1 h recovery from the final stress session, whole-cell patch-clamp electrophysiology was used to investigate the effects of CRF (200 nM) on CeA GABAA-mediated spontaneous inhibitory postsynaptic currents (sIPSCs). TLR4 does not regulate baseline GABAergic transmission in the CeA of naive and stress-treated animals. However, CRF significantly increased the mean sIPSC frequencies (indicating enhanced GABA release) across all genotypes and stress treatments, except for the Tlr4 KO rats that experienced repeated restraint stress. Overall, our results suggest a limited role for TLR4 in CRF's modulation of CeA GABAergic synapses in naïve and single stress rats, though TLR4-deficient rats that experienced repeated psychological stress exhibit a blunted CRF cellular response. TLR4 has a limited role in CRF's activation of the CeA under basal conditions, but interacts with the CRF system to regulate GABAergic synapse function in animals that experience repeated psychological stress. © The Author(s) 2018. Medical Council on Alcohol and Oxford University Press. All rights reserved.

Differential host response to LPS variants in amniochorion and the TLR4/MD-2 system in Macaca nemestrina

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Chang, Justine; Jain, Sumita; Carl, David J.; Paolella, Louis; Darveau, Richard P.; Gravett, Michael G.; Waldorf, Kristina M. Adams

2010-01-01

OBJECTIVES Microbial-specific factors are likely critical in determining whether bacteria trigger preterm labor. Structural variations in lipopolysaccharide (LPS), a component of gram-negative bacteria, can determine whether LPS has an inflammatory (agonist) or anti-inflammatory (antagonist) effect through Toll-like receptor 4 (TLR4). Our objective was to determine whether amniochorion can discriminate between LPS variants in a nonhuman primate model. We also cloned Macaca nemestrina TLR4 and MD-2 and compared this complex functionally to the human homologue to establish whether nonhuman primates could be used to study TLR4 signaling in preterm birth. STUDY DESIGN Amniochorion explants from M. nemestrina were stimulated with a panel of LPS variants for 24 hours. Supernatants were analyzed for IL-1β, TNF-α, IL-6, IL-8 and prostaglandins E2 and F2α. Tissue expression of TLR1, 2, 4, 6, MyD88 and NF-kB was studied by RT-PCR. M. nemestrina TLR4 and MD2 genes were cloned and compared with their human counterparts in a recombinant TLR4 signaling system to determine LPS sensitivity. RESULTS LPS variants differentially stimulated cytokines and prostaglandins, which was not related to transcriptional changes of TLR4 or other TLRs. Nearly all elements of LPS binding and TLR4 leucine-rich repeats were conserved between humans and M. nemestrina. TLR4/MD-2 signaling complexes from both species were equally sensitive to LPS variants. CONCLUSIONS LPS variants elicit a hierarchical inflammatory response within amniochorion that may contribute to preterm birth. LPS sensitivity is similar between M. nemestrina and humans, validating M. nemestrina as an appropriate model to study TLR4 signaling in preterm birth. PMID:20619890

A Role for TLR4 in Clostridium difficile Infection and the Recognition of Surface Layer Proteins.

LENUS (Irish Health Repository)

Ryan, Anthony

2011-06-01

Clostridium difficile is the etiological agent of antibiotic-associated diarrhoea (AAD) and pseudomembranous colitis in humans. The role of the surface layer proteins (SLPs) in this disease has not yet been fully explored. The aim of this study was to investigate a role for SLPs in the recognition of C. difficile and the subsequent activation of the immune system. Bone marrow derived dendritic cells (DCs) exposed to SLPs were assessed for production of inflammatory cytokines, expression of cell surface markers and their ability to generate T helper (Th) cell responses. DCs isolated from C3H\\/HeN and C3H\\/HeJ mice were used in order to examine whether SLPs are recognised by TLR4. The role of TLR4 in infection was examined in TLR4-deficient mice. SLPs induced maturation of DCs characterised by production of IL-12, TNFα and IL-10 and expression of MHC class II, CD40, CD80 and CD86. Furthermore, SLP-activated DCs generated Th cells producing IFNγ and IL-17. SLPs were unable to activate DCs isolated from TLR4-mutant C3H\\/HeJ mice and failed to induce a subsequent Th cell response. TLR4(-\\/-) and Myd88(-\\/-), but not TRIF(-\\/-) mice were more susceptible than wild-type mice to C. difficile infection. Furthermore, SLPs activated NFκB, but not IRF3, downstream of TLR4. Our results indicate that SLPs isolated from C. difficile can activate innate and adaptive immunity and that these effects are mediated by TLR4, with TLR4 having a functional role in experimental C. difficile infection. This suggests an important role for SLPs in the recognition of C. difficile by the immune system.

TLR2 and TLR4 signaling pathways are required for recombinant Brucella abortus BCSP31-induced cytokine production, functional upregulation of mouse macrophages, and the Th1 immune response in vivo and in vitro.

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Li, Jia-Yun; Liu, Yuan; Gao, Xiao-Xue; Gao, Xiang; Cai, Hong

2014-09-01

Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors (TLRs) recognize Brucella abortus and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. In this study, we focused on recombinant Brucella cell-surface protein 31 (rBCSP31) to determine its effects on mouse macrophages. Our results demonstrated that rBCSP31 induced TNF-α, IL-6 and IL-12p40 production, which depended on the activation of mitogen-activated protein kinases (MAPKs) by stimulating the rapid phosphorylation of p38 and JNK and the activation of transcription factor NF-κB in macrophages. In addition, continuous exposure (>24 h) of RAW264.7 cells to rBCSP31 significantly enhanced IFN-γ-induced expression of MHC-II and the ability to present rBCSP31 peptide to CD4(+) T cells. Furthermore, we found that rBCSP31 could interact with both TLR2 and TLR4. The rBCSP31-induced cytokine production by macrophages from TLR2(-/-) and TLR4(-/-) mice was lower than that from C57BL/6 macrophages, and the activation of NF-κB and MAPKs was attenuated in macrophages from TLR2(-/-) and TLR4(-/-) mice. In addition, CD4(+) T cells from C57BL/6 mice immunized with rBCSP31 produced higher levels of IFN-γ and IL-2 compared with CD4(+) T cells from TLR2(-/-) and TLR4(-/-) mice. Macrophages from immunized C57BL/6 mice produced higher levels of IL-12p40 than those from TLR2(-/-) and TLR4(-/-) mice. Furthermore, immunization with rBCSP31 provided better protection in C57BL/6 mice than in TLR2(-/-) and TLR4(-/-) mice after B. abortus 2308 challenge. These results indicate that rBCSP31 is a TLR2 and TLR4 agonist that induces cytokine production, upregulates macrophage function and induces the Th1 immune response.

Ursolic acid isolated from Uncaria rhynchophylla activates human dendritic cells via TLR2 and/or TLR4 and induces the production of IFN-gamma by CD4+ naïve T cells.

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Jung, Tae-Young; Pham, Thanh Nhan Nguyen; Umeyama, Akemi; Shoji, Noboru; Hashimoto, Toshihiro; Lee, Je-Jung; Takei, Masao

2010-09-25

Ursolic acid is triterpene isolated from Uncaria rhynchophylla and is a pharmacologically active substance. The induction of dendritic cell maturation is critical for the induction of Ag-specific T-lymphocyte response and may be essential for the development of human vaccine relying on T cell immunity. In this study, we investigated that the effect of Ursolic acid on the phenotypic and functional maturation of human monocyte-derived dendritic cells in vitro. Dendritic cells harvested on day 8 were examined using functional assay. The expression levels of CD1a, CD80, CD83, CD86, HLA-DR and CCR7 on Ursolic acid-primed dendritic cells was slightly enhanced. Ursolic acid dose-dependently enhanced the T cell stimulatory capacity in an allogeneic mixed lymphocyte reaction, as measured by T cell proliferation. The production of IL-12p70 induced by Ursolic acid-primed dendritic cells was inhibited by the anti-Toll-like receptor-2 (TLR2) mAb and anti-TLR4 mAb. Moreover, Ursolic acid-primed dendritic cells expressed levels of mRNA coding for both TLR2 and TLR4. The majority of cells produced considerable interferon-gamma (IFN-gamma), but also small amounts of interleukin (IL-4)-4. Ursolic acid-primed dendritic cells have an intermediate migratory capacity towards CCL19 and CCL21. These results suggest that Ursolic acid modulates human dendritic cells function in a fashion that favors Th1 polarization via the activation of IL-12p70 dependent on TLR2 and/or TLR4, and may be used on dendritic cells-based vaccines for cancer immunotherapy. 2010 Elsevier B.V. All rights reserved.

Electroacupuncture Improved Hippocampal Neurogenesis following Traumatic Brain Injury in Mice through Inhibition of TLR4 Signaling Pathway

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Yuqin Ye

2017-01-01

Full Text Available The protective role of electroacupuncture (EA treatment in diverse neurological diseases such as ischemic stroke is well acknowledged. However, whether and how EA act on hippocampal neurogenesis following traumatic brain injury (TBI remains poorly understood. This study aims to investigate the effect of EA on hippocampal neurogenesis and neurological functions, as well as its underlying association with toll-like receptor 4 (TLR4 signaling in TBI mice. BrdU/NeuN immunofluorescence was performed to label newborn neurons in the hippocampus after EA treatment. Water maze test and neurological severity score were used to evaluate neurological function posttrauma. The hippocampal level of TLR4 and downstream molecules and inflammatory cytokines were, respectively, detected by Western blot and enzyme-linked immunosorbent assay. EA enhanced hippocampal neurogenesis and inhibited TLR4 expression at 21, 28, and 35 days after TBI, but the beneficial effects of EA on posttraumatic neurogenesis and neurological functions were attenuated by lipopolysaccharide-induced TLR4 activation. In addition, EA exerted an inhibitory effect on both TLR4/Myd88/NF-κB and TLR4/TRIF/NF-κB pathways, as well as the inflammatory cytokine expression in the hippocampus following TBI. In conclusion, EA promoted hippocampal neurogenesis and neurological recovery through inhibition of TLR4 signaling pathway posttrauma, which may be a potential approach to improve the outcome of TBI.

Toll-like receptor 4 mediates microglial activation and production of inflammatory mediators in neonatal rat brain following hypoxia: role of TLR4 in hypoxic microglia

Science.gov (United States)

2013-01-01

Background Hypoxia induces microglial activation which causes damage to the developing brain. Microglia derived inflammatory mediators may contribute to this process. Toll-like receptor 4 (TLR4) has been reported to induce microglial activation and cytokines production in brain injuries; however, its role in hypoxic injury remains uncertain. We investigate here TLR4 expression and its roles in neuroinflammation in neonatal rats following hypoxic injury. Methods One day old Wistar rats were subjected to hypoxia for 2 h. Primary cultured microglia and BV-2 cells were subjected to hypoxia for different durations. TLR4 expression in microglia was determined by RT-PCR, western blot and immunofluorescence staining. Small interfering RNA (siRNA) transfection and antibody neutralization were employed to downregulate TLR4 in BV-2 and primary culture. mRNA and protein expression of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and inducible nitric oxide synthase (iNOS) was assessed. Reactive oxygen species (ROS), nitric oxide (NO) and NF-κB levels were determined by flow cytometry, colorimetric and ELISA assays respectively. Hypoxia-inducible factor-1 alpha (HIF-1α) mRNA and protein expression was quantified and where necessary, the protein expression was depleted by antibody neutralization. In vivo inhibition of TLR4 with CLI-095 injection was carried out followed by investigation of inflammatory mediators expression via double immunofluorescence staining. Results TLR4 immunofluorescence and protein expression in the corpus callosum and cerebellum in neonatal microglia were markedly enhanced post-hypoxia. In vitro, TLR4 protein expression was significantly increased in both primary microglia and BV-2 cells post-hypoxia. TLR4 neutralization in primary cultured microglia attenuated the hypoxia-induced expression of TNF-α, IL-1β and iNOS. siRNA knockdown of TLR4 reduced hypoxia-induced upregulation of TNF-α, IL-1β, iNOS, ROS and NO in BV-2 cells. TLR4

Combined paracetamol and amitriptyline adsorption to activated charcoal

DEFF Research Database (Denmark)

Hoegberg, Lotte Christine Groth; Groenlykke, Thor Buch; Abildtrup, Ulla

2010-01-01

Objectives. High-gram drug doses seen in multiple-drug poisonings might be close to the adsorption capacity of activated charcoal (AC). The aim was to determine the maximum adsorption capacities (Q(m)) of amitriptyline and paracetamol, separately and in combination, to AC. Methods. ACs (Carbomix......® and Norit Ready-To-Use) were tested in vitro. At pH 1.2 and pH 7.2, 0.250 g AC and paracetamol and/or amitriptyline were mixed and incubated. The AC: drug ratios were 10:1, 5:1, 3:1, 2:1, and 1:1. The mixed-drug adsorption vials contained the same AC: paracetamol ratios, but amitriptyline was added as fixed...... Ready-To-Use. The tested pH differences had minor effect on the adsorption. The mixed-drug adsorption showed about 40% Q(m) reduction of each drug with increasing amounts of drug/g AC, but the total gram of drug adsorbed to AC was increased compared to one-drug conditions. Conclusion. The adsorption...

TLR4 mutation reduces microglial activation, increases Aβ deposits and exacerbates cognitive deficits in a mouse model of Alzheimer's disease

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Song Min

2011-08-01

Full Text Available Abstract Background Amyloid plaques, a pathological hallmark of Alzheimer's disease (AD, are accompanied by activated microglia. The role of activated microglia in the pathogenesis of AD remains controversial: either clearing Aβ deposits by phagocytosis or releasing proinflammatory cytokines and cytotoxic substances. Microglia can be activated via toll-like receptors (TLRs, a class of pattern-recognition receptors in the innate immune system. We previously demonstrated that an AD mouse model homozygous for a loss-of-function mutation of TLR4 had increases in Aβ deposits and buffer-soluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model at 14-16 months of age. However, it is unknown if TLR4 signaling is involved in initiation of Aβ deposition as well as activation and recruitment of microglia at the early stage of AD. Here, we investigated the role of TLR4 signaling and microglial activation in early stages using 5-month-old AD mouse models when Aβ deposits start. Methods Microglial activation and amyloid deposition in the brain were determined by immunohistochemistry in the AD models. Levels of cerebral soluble Aβ were determined by ELISA. mRNA levels of cytokines and chemokines in the brain and Aβ-stimulated monocytes were quantified by real-time PCR. Cognitive functions were assessed by the Morris water maze. Results While no difference was found in cerebral Aβ load between AD mouse models at 5 months with and without TLR4 mutation, microglial activation in a TLR4 mutant AD model (TLR4M Tg was less than that in a TLR4 wild-type AD model (TLR4W Tg. At 9 months, TLR4M Tg mice had increased Aβ deposition and soluble Aβ42 in the brain, which were associated with decrements in cognitive functions and expression levels of IL-1β, CCL3, and CCL4 in the hippocampus compared to TLR4W Tg mice. TLR4 mutation diminished Aβ-induced IL-1β, CCL3, and CCL4 expression in monocytes. Conclusion This is the first demonstration of TLR4

Suppression of TLR4-mediated inflammatory response by macrophage class A scavenger receptor (CD204)

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Ohnishi, Koji; Komohara, Yoshihiro; Fujiwara, Yukio; Takemura, Kenichi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Lei, XiaoFeng [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Biochemistry, Showa University School of Medicine, Tokyo (Japan); Nakagawa, Takenobu [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Sakashita, Naomi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Human Pathology, Institute of Health Biosciences, The University of Tokushima, Tokushima (Japan); Takeya, Motohiro, E-mail: takeya@kumamoto-u.ac.jp [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

2011-08-05

Highlights: {yields} We focused on the interaction between SR-A and TLR4 signaling in this study. {yields} SR-A deletion promoted NF{kappa}B activation in macrophages in septic model mouse. {yields} SR-A suppresses both MyD88-dependent and -independent TLR4 signaling in vitro. {yields} SR-A clears LPS binding to TLR4 which resulting in the suppression of TLR4 signals. -- Abstract: The class A scavenger receptor (SR-A, CD204), one of the principal receptors expressed on macrophages, has been found to regulate inflammatory response and attenuate septic endotoxemia. However, the detailed mechanism of this process has not yet been well characterized. To clarify the regulative mechanisms of lipopolysaccharide (LPS)-induced macrophage activation by SR-A, we evaluated the activation of Toll-like receptor 4 (TLR4)-mediated signaling molecules in SR-A-deficient (SR-A{sup -/-}) macrophages. In a septic shock model, the blood levels of tumor necrosis factor (TNF)-{alpha}, interleukin (IL)-6 and interferon (IFN)-{beta} were significantly increased in SR-A{sup -/-} mice compared to wild-type mice, and elevated nuclear factor kappa B (NF{kappa}B) activation was detected in SR-A{sup -/-} macrophages. SR-A deletion increased the production of pro-inflammatory cytokines, and the phosphorylation of mitogen-activated protein kinase (MAPK) and NF{kappa}B in vitro. SR-A deletion also promoted the nuclear translocation of NF{kappa}B and IFN regulatory factor (IRF)-3. In addition, a competitive binding assay with acetylated low-density lipoprotein, an SR-A-specific ligand, and anti-SR-A antibody induced significant activation of TLR4-mediated signaling molecules in wild-type macrophages but not in SR-A{sup -/-} macrophages. These results suggest that SR-A suppresses the macrophage activation by inhibiting the binding of LPS to TLR4 in a competitive manner and it plays a pivotal role in the regulation of the LPS-induced inflammatory response.

Neuroleptic Malignant Syndrome Caused by a Combination of Carbamazepine and Amitriptyline

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A. Bruce Janati

2012-01-01

Full Text Available A 32-year-old female, with a history of secondarily-generalized convulsive epilepsy, mental retardation, and a psychiatric illness, developed neuroleptic malignant syndrome while receiving carbamazepine and amitriptyline concurrently. We hypothesize that the addition of amitriptyline to carbamazepine caused a decrease in the serum level of carbamazepine, resulting in NMS. We conclude that combination therapy with carbamazepine and amitriptyline should be avoided in patients who are predisposed to NMS. The purpose of this paper is to warn physicians against combination therapy with carbamazepine and tricyclic antidepressants which may be conducive to neuroleptic malignant syndrome in susceptible patients.

Chronic intermittent hypoxia exerts CNS region-specific effects on rat microglial inflammatory and TLR4 gene expression.

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Stephanie M C Smith

Full Text Available Intermittent hypoxia (IH during sleep is a hallmark of sleep apnea, causing significant neuronal apoptosis, and cognitive and behavioral deficits in CNS regions underlying memory processing and executive functions. IH-induced neuroinflammation is thought to contribute to cognitive deficits after IH. In the present studies, we tested the hypothesis that IH would differentially induce inflammatory factor gene expression in microglia in a CNS region-dependent manner, and that the effects of IH would differ temporally. To test this hypothesis, adult rats were exposed to intermittent hypoxia (2 min intervals of 10.5% O2 for 8 hours/day during their respective sleep cycles for 1, 3 or 14 days. Cortex, medulla and spinal cord tissues were dissected, microglia were immunomagnetically isolated and mRNA levels of the inflammatory genes iNOS, COX-2, TNFα, IL-1β and IL-6 and the innate immune receptor TLR4 were compared to levels in normoxia. Inflammatory gene expression was also assessed in tissue homogenates (containing all CNS cells. We found that microglia from different CNS regions responded to IH differently. Cortical microglia had longer lasting inflammatory gene expression whereas spinal microglial gene expression was rapid and transient. We also observed that inflammatory gene expression in microglia frequently differed from that in tissue homogenates from the same region, indicating that cells other than microglia also contribute to IH-induced neuroinflammation. Lastly, microglial TLR4 mRNA levels were strongly upregulated by IH in a region- and time-dependent manner, and the increase in TLR4 expression appeared to coincide with timing of peak inflammatory gene expression, suggesting that TLR4 may play a role in IH-induced neuroinflammation. Together, these data indicate that microglial-specific neuroinflammation may play distinct roles in the effects of intermittent hypoxia in different CNS regions.

Innate immune response of alveolar macrophage to house dust mite allergen is mediated through TLR2/-4 co-activation.

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Chia-Fang Liu

Full Text Available House dust mite, Dermatophagoides pteronyssinus (Der p, is one of the major allergens responsible for allergic asthma. However, the putative receptors involved in the signalization of Der p to the innate immune cells are still poorly defined as well as the impact of their activation on the outcome of the allergen-induced cell response. We previously reported that the HDM activation of mouse alveolar macrophages (AM involves the TLR4/CD14 cell surface receptor complex. Here using a TLR ligand screening essay, we demonstrate that HDM protein extract engages the TLR2, in addition to the TLR4, in engineered TLR-transfected HEK cells but also in the MH-S mouse alveolar macrophage cell line model. Moreover we found that the concomitant recruitment of the MH-S cell's TLR2 and TLR4 receptors by the HDM extract activates the MyD88-dependent signaling pathway and leads to the secretion of the NF-κB regulated pro-inflammatory factors NO and TNF-α. However unlike with the canonical TLR4 ligand (i.e. the bacterial LPS mobilization of TLR4 by the HDM extract induces a reduced production of the IL-12 pro-inflammatory cytokine and fails to trigger the expression of the T-bet transcription factor. Finally we demonstrated that HDM extract down-regulates LPS induced IL-12 and T-bet expression through a TLR2 dependent mechanism. Therefore, we propose that the simultaneous engagement of the TLR2 and TLR4 receptors by the HDM extract results in a cross regulated original activation pattern of the AM which may contribute to the Th2 polarization of the allergen-induced immune response. The deciphering of these cross-regulation networks is of prime importance to open the way for original therapeutic strategies taking advantage of these receptors and their associated signaling pathways to treat allergic asthma.

Randomized, Double-Blind, Crossover Trial of Amitriptyline for Analgesia in Painful HIV-Associated Sensory Neuropathy.

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Natalya Dinat

Full Text Available We conducted a randomized, double-blind, placebo-controlled, crossover study at a single center in South Africa, to ascertain whether amitriptyline is an effective analgesic for painful HIV-associated sensory neuropathy of moderate to severe intensity in: i antiretroviral drug naive individuals, and ii antiretroviral drug users. 124 HIV-infected participants (antiretroviral drug naive = 62, antiretroviral drug users = 62 who met the study criteria for painful HIV-associated sensory neuropathy were randomized to once-daily oral amitriptyline (titrated to a median: interquartile range of 50: 25-50 mg or placebo for six weeks, followed by a three-week washout period and subsequent treatment crossover. The primary outcome measure was change from baseline in worst pain intensity of the feet (measured by participant self-report using an 11-point numerical pain rating scale after six weeks of treatment. 122 of 124 participants completed all study visits and were included in the analysis of the primary outcome. In the antiretroviral drug-naive group (n = 61 there was no significant difference in the mean change in pain score from baseline after six weeks of treatment with placebo or amitriptyline [amitriptyline: 2.8 (SD 3.3 vs. placebo: 2.8 (3.4]. Similarly, there was no significant difference in the change in pain score after six weeks of treatment with placebo or amitriptyline in the antiretroviral drug-user group (n = 61 [amitriptyline: 2.7 (3.3 vs. placebo: 2.1 (2.8]. Controlling for period effects and treatment order effects did not alter the outcome of the analyses. Nor did analyzing the intention-to-treat cohort (missing data interpolated using baseline observation carried forward alter the outcome of the analyses. In summary, amitriptyline, at the doses used here, was no more effective than an inactive placebo at reducing pain intensity in individuals with painful HIV-associated sensory neuropathy of moderate to severe intensity, irrespective of

Hypnagogic and hypnopompic hallucinations during amitriptyline treatment.

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Hemmingsen, R; Rafaelsen, O J

1980-10-01

Four cases of hypnagogic or hypnopompic visual hallucinations in patients during amitriptyline treatment are reported. The hallucinations were clearly delineated, projected to the outer objective space and were for a short time experienced as real. The patients rapidly realized the unreality of the "sights", probably because they regained the full criticism and coherent thinking of an unpsychotic awake individual. There may be a relation between the effects of amitriptyline in brain, the changed pattern of sleep and the clinical recovery. Patients should be informed about the benign character of this type of hallucinatory phenomena so that treatment is not terminated at an undue time.

Trauma hemorrhagic shock-induced lung injury involves a gut-lymph-induced TLR4 pathway in mice.

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Diego C Reino

Full Text Available Injurious non-microbial factors released from the stressed gut during shocked states contribute to the development of acute lung injury (ALI and multiple organ dysfunction syndrome (MODS. Since Toll-like receptors (TLR act as sensors of tissue injury as well as microbial invasion and TLR4 signaling occurs in both sepsis and noninfectious models of ischemia/reperfusion (I/R injury, we hypothesized that factors in the intestinal mesenteric lymph after trauma hemorrhagic shock (T/HS mediate gut-induced lung injury via TLR4 activation.The concept that factors in T/HS lymph exiting the gut recreates ALI is evidenced by our findings that the infusion of porcine lymph, collected from animals subjected to global T/HS injury, into naïve wildtype (WT mice induced lung injury. Using C3H/HeJ mice that harbor a TLR4 mutation, we found that TLR4 activation was necessary for the development of T/HS porcine lymph-induced lung injury as determined by Evan's blue dye (EBD lung permeability and myeloperoxidase (MPO levels as well as the induction of the injurious pulmonary iNOS response. TRIF and Myd88 deficiency fully and partially attenuated T/HS lymph-induced increases in lung permeability respectively. Additional studies in TLR2 deficient mice showed that TLR2 activation was not involved in the pathology of T/HS lymph-induced lung injury. Lastly, the lymph samples were devoid of bacteria, endotoxin and bacterial DNA and passage of lymph through an endotoxin removal column did not abrogate the ability of T/HS lymph to cause lung injury in naïve mice.Our findings suggest that non-microbial factors in the intestinal mesenteric lymph after T/HS are capable of recreating T/HS-induced lung injury via TLR4 activation.

Quantitative determination of amitriptyline and its metabolite in rat plasma by liquid chromatography-tandem mass spectrometry

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Chae, Jungwoo; Baek, Inhwan; An, Junghwa; Kim, Eun Jung; Kwon, Kwangil [Chungnam National Univ., Daejeon (Korea, Republic of)

2012-07-15

A rapid, specific, and reliable LC-MS/MS-based bioanalytical method was developed and validated in rat plasma for the simultaneous quantitation of amitriptyline and its metabolite nortriptyline. Chromatographic separation of these analytes was achieved on a Gemini C18 column (50 X 4.60 mm, 5 {mu}m) using reversed-phase chromatography. The mobile phase was an isocratic solvent system consisting of 1% formic acid in water and methanol (10:90, v/v), at a flow rate of 0.2 mL/min. The analytical range was set as 0.1-500 ng/mL for amitriptyline and 0.08-500 ng/mL for nortriptyline using a 200 {mu}L plasma sample. The accuracy and precision of the assay were in accordance with FDA regulations for the validation of bioanalytical methods. The validated method was successfully applied to a pharmacokinetic study in six rats after oral administration of amitriptyline (15 mg/kg). This method allows laboratory scientists to rapidly determine amitriptyline and nortriptyline concentrations in plasma.

Correlation between Amitriptyline-Induced Cardiotoxic Effects and Cardiac S100b Protein in Isolated Rat Hearts

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Nil Hocaoğlu

2016-12-01

Full Text Available Background: Amitriptyline is an important cause of mortality due to its cardiovascular toxicity. Aims: To investigate the changes in levels of cardiac S100b protein on amitriptyline-induced cardiotoxicity and also to examine the correlation between amitriptyline-induced cardiotoxic effects and cardiac S100b protein in an isolated rat heart model. Study Design: Animal experimentation, isolated heart model. Methods: After a stabilization period, isolated hearts were randomized to two groups (n=5 and n=7. In the control group, isolated hearts were subjected to an infusion of 5% dextrose for 60 minutes. In the amitriptyline group, 5.5×10-5 M amitriptyline was infused for 60 minutes to achieve amitriptyline toxicity. After the infusion period, heart tissues were removed for histological examination. Results: In comparison to control treatment, amitriptyline infusion decreased left ventricular developed pressure (LVDP, dp/dtmax and heart rate (HR and significantly prolonged QRS duration (p<0.05. The semiquantitative scores for S100b protein levels in amitriptyline-infused hearts were higher than in the control group (p<0.01. At the end of the experiment, in the amitriptyline-infused group, significant correlations were found between LVDP and S100b protein scores (r=-0.807, p=0.003 and between QRS duration and S100b protein scores (r=0.859, p=0.001. Conclusion: Our results indicate that the S100b protein may be a helpful indicator or biomarker in studying the cardiotoxic effects of amitriptyline.

The Roles of Bacteria and TLR4 in Rat and Murine Models of Necrotizing Enterocolitis1

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Jilling, Tamas; Simon, Dyan; Lu, Jing; Meng, Fan Jing; Li, Dan; Schy, Robert; Thomson, Richard B.; Soliman, Antoine; Arditi, Moshe; Caplan, Michael S.

2009-01-01

Bacteria are thought to contribute to the pathogenesis of necrotizing enterocolitis (NEC), but it is unknown whether their interaction with the epithelium can participate in the initiation of mucosal injury or they can act only following translocation across a damaged intestinal barrier. Our aims were to determine whether bacteria and intestinal epithelial TLR4 play roles in a well-established neonatal rat model and a novel neonatal murine model of NEC. Neonatal rats, C57BL/6J, C3HeB/FeJ (TLR4 wild type), and C3H/HeJ (TLR4 mutant) mice were delivered by Cesarean section and were subjected to formula feeding and cold asphyxia stress or were delivered naturally and were mother-fed. NEC incidence was evaluated by histological scoring, and gene expression was quantified using quantitative real-time PCR from cDNA generated from intestinal total RNA or from RNA obtained by laser capture microdissection. Spontaneous feeding catheter colonization or supplementation of cultured bacterial isolates to formula increased the incidence of experimental NEC. During the first 72 h of life, i.e., the time frame of NEC development in this model, intestinal TLR4 mRNA gradually decreases in mother-fed but increases in formula feeding and cold asphyxia stress, correlating with induced inducible NO synthase. TLR4, inducible NO synthase, and inflammatory cytokine induction occurred in the intestinal epithelium but not in the submucosa. NEC incidence was diminished in C3H/HeJ mice, compared with C3HeB/FeJ mice. In summary, bacteria and TLR4 play significant roles in experimental NEC, likely via an interaction of intraluminal bacteria and aberrantly overexpressed TLR4 in enterocytes. PMID:16920968

Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation.

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Kirschning, Carsten J; Dreher, Stefan; Maass, Björn; Fichte, Sylvia; Schade, Jutta; Köster, Mario; Noack, Andreas; Lindenmaier, Werner; Wagner, Hermann; Böldicke, Thomas

2010-04-13

Toll-like receptor (TLR) 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs) of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs) contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies) are applied to block translocation of secreted and cell surface molecules from the ER to the cell surface resulting in functional inhibition of the target protein. Here we describe generation and application of a functional anti-TLR2 ER intrabody (alphaT2ib) which was generated from an antagonistic monoclonal antibody (mAb) towards human and murine TLR2 (T2.5) to inhibit the function of TLR2. alphaT2ib is a scFv fragment comprising the variable domain of the heavy chain and the variable domain of the light chain of mAb T2.5 linked together by a synthetic (Gly4Ser)3 amino acid sequence. Coexpression of alphaT2ib and mouse TLR2 in HEK293 cells led to efficient retention and accumulation of TLR2 inside the ER compartment. Co-immunoprecipitation of human TLR2 with alphaT2ib indicated interaction of alphaT2ib with its cognate antigen within cells. alphaT2ib inhibited NF-kappaB driven reporter gene activation via TLR2 but not through TLR3, TLR4, or TLR9 if coexpressed in HEK293 cells. Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding alphaT2ib into HEK293 cells demonstrated high efficiency of the TLR2-alphaT2ib interaction. The alphaT2ib open reading frame was integrated into an adenoviral cosmid vector for production of recombinant adenovirus (AdV)-alphaT2ib. Transduction with AdValphaT2ib specifically inhibited TLR2 surface expression of murine RAW264.7 and primary macrophages derived from bone marrow (BMM). Furthermore, TLR2 activation dependent TNFalpha mRNA accumulation, as

Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy

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Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A.; Sung, Junne-Ming; Tsai, Yau-Sheng

2015-01-01

ABSTRACT Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-κB promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4−/− mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

TOLL-LIKE RECEPTORS (TLR 2 AND 4 EXPRESSION OF KERATINOCYTES FROM PATIENTS WITH LOCALIZED AND DISSEMINATED DERMATOPHYTOSIS

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Cristiane Beatriz de Oliveira

2015-02-01

Full Text Available There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs 2 and 4 in localized (LD and disseminated (DD dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.

Impact of TLR4 on behavioral and cognitive dysfunctions associated with alcohol-induced neuroinflammatory damage.

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Pascual, María; Baliño, Pablo; Alfonso-Loeches, Silvia; Aragón, Carlos M G; Guerri, Consuelo

2011-06-01

Toll-like receptors (TLRs) play an important role in the innate immune response, and emerging evidence indicates their role in brain injury and neurodegeneration. Our recent results have demonstrated that ethanol is capable of activating glial TLR4 receptors and that the elimination of these receptors in mice protects against ethanol-induced glial activation, induction of inflammatory mediators and apoptosis. This study was designed to assess whether ethanol-induced inflammatory damage causes behavioral and cognitive consequences, and if behavioral alterations are dependent of TLR4 functions. Here we show in mice drinking alcohol for 5months, followed by a 15-day withdrawal period, that activation of the astroglial and microglial cells in frontal cortex and striatum is maintained and that these events are associated with cognitive and anxiety-related behavioral impairments in wild-type (WT) mice, as demonstrated by testing the animals with object memory recognition, conditioned taste aversion and dark and light box anxiety tasks. Mice lacking TLR4 receptors are protected against ethanol-induced inflammatory damage, and behavioral associated effects. We further assess the possibility of the epigenetic modifications participating in short- or long-term behavioral effects associated with neuroinflammatory damage. We show that chronic alcohol treatment decreases H4 histone acetylation and histone acetyltransferases activity in frontal cortex, striatum and hippocampus of WT mice. Alterations in chromatin structure were not observed in TLR4(-/-) mice. These results provide the first evidence of the role that TLR4 functions play in the behavioral consequences of alcohol-induced inflammatory damage and suggest that the epigenetic modifications mediated by TLR4 could contribute to short- or long-term alcohol-induced behavioral or cognitive dysfunctions. Copyright © 2011 Elsevier Inc. All rights reserved.

Molecular characterization and expression profile of partial TLR4 gene in association to mastitis in crossbred cattle.

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Panigrahi, Manjit; Sharma, Arjava; Bhushan, Bharat

2014-01-01

Crossbred cattle are more prone to mastitis in comparison to indigenous cattle. Toll-like receptor 4 (TLR4) recognizes pathogen ligands, for example, lipopolysaccharide (LPS) endotoxin from Escherichia coli and mediates signaling to initiate innate and adaptive immune responses. Mutations in TLR4 can compromise the host immune response to certain pathogens, so it may be a potential candidate for marker assisted selection to enhance mastitis resistance in dairy cattle. Hence, in this study role of bovine TLR4 gene in mastitis resistance was investigated by association as well as expression profiling analysis in crossbred cattle. The animals were divided into mastitis affected and unaffected groups on the basis of history of animals and California Mastitis Test (CMT). PCR-SSCP and Sequence analysis revealed three genotypes of coreceptor binding region 1 (CRBR1) fragment of TLR4 gene namely AA, AB, and BB in both groups of cattle. The logistic regression model did not show any significant effect of these genotypes on the occurrence of clinical mastitis. Moreover, in vitro challenge of peripheral blood mononuclear cells (PBMCs) with LPS failed to show any association of the genotypes with TLR4 gene expression. In a nutshell, in the present study enough evidence was not found for association of the SNP variants of CRBR1 fragment of TLR4 gene with mastitis susceptibility in crossbred cattle.

Andrographolide inhibits multiple myeloma cells by inhibiting the TLR4/NF-κB signaling pathway.

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Gao, Hui; Wang, Jianrong

2016-02-01

Andrographolide is an active component from the extract of Andrographis paniculata [(Burm.f) Nees], a medicinal plant from the Acanthaceae family. Pharmacological studies have revealed that andrographolide possesses anti-bacterial, anti-inflammatory, anti-viral, immune regulatory and hepatoprotective properties, and is efficacious in the treatment of cardiovascular diseases, while exhibiting low toxicity and low cost. The present study aimed to determine the inhibitory effects of andrographolide on the growth of multiple myeloma (MM) cells and its possible impact on the Toll-like receptor (TLR)4/nuclear factor (NF)-κB signaling pathway. Cell proliferation was detected using an MTT assay, cellular apoptosis was measured using flow cytometry, and caspase-9/3 activation were assessed using colorimetric assay kits. Furthermore, TLR4 and NF-κB protein expression was determined by western blot analysis. The results revealed that andrographolide reduced the proliferation, while increasing cellular apoptosis and caspase-9/3 activation of MM cells, in addition to downregulating the expression of TLR4 and NF-κB protein. Of note, TLR4- or NF-κB-targeting small-interfering (si)RNA enhanced the andrographolide-induced inhibition of cell proliferation and induction of apoptosis of MM cells. The results of the present study therefore suggested that andrographolide inhibited multiple myeloma cells via the TLR4/NF-κB signaling pathway.

Mycobacterial Phenolic Glycolipids Selectively Disable TRIF-Dependent TLR4 Signaling in Macrophages

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Reid Oldenburg

2018-01-01

Full Text Available Phenolic glycolipids (PGLs are cell wall components of a subset of pathogenic mycobacteria, with immunomodulatory properties. Here, we show that in addition, PGLs exert antibactericidal activity by limiting the production of nitric oxide synthase (iNOS in mycobacteria-infected macrophages. PGL-mediated downregulation of iNOS was complement receptor 3-dependent and comparably induced by bacterial and purified PGLs. Using Mycobacterium leprae PGL-1 as a model, we found that PGLs dampen the toll-like receptor (TLR4 signaling pathway, with macrophage exposure to PGLs leading to significant reduction in TIR-domain-containing adapter-inducing interferon-β (TRIF protein level. PGL-driven decrease in TRIF operated posttranscriptionally and independently of Src-family tyrosine kinases, lysosomal and proteasomal degradation. It resulted in the defective production of TRIF-dependent IFN-β and CXCL10 in TLR4-stimulated macrophages, in addition to iNOS. Our results unravel a mechanism by which PGLs hijack both the bactericidal and inflammatory responses of host macrophages. Moreover, they identify TRIF as a critical node in the crosstalk between CR3 and TLR4.

An apple oligogalactan prevents against inflammation and carcinogenesis by targeting LPS/TLR4/NF-κB pathway in a mouse model of colitis-associated colon cancer.

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Liu, Li; Li, Yu H; Niu, Yin B; Sun, Yang; Guo, Zhen J; Li, Qian; Li, Chen; Feng, Juan; Cao, Shou S; Mei, Qi B

2010-10-01

Evidence strongly supported a link between inflammation and cancer. Patients with colitis have high risk for development of colon cancer. Nuclear factor-kappa B (NF-κB), partially induced by lipopolysaccharide (LPS) binding to Toll-like receptor (TLR) 4, is a vital molecule in supervising the transformation of colitis to colon cancer. It could be a good strategy to prevent colitis carcinogenesis for targeting LPS/TLR4/NF-κB pathway. In the present study, we obtained an oligogalactan composed of five galacturonic acids from apple pectin and evaluated its protective efficacy on intestinal toxicities and carcinogenesis in a mouse model of colitis-associated colon cancer induced by 1,2-dimethylhydrazine and dextran sodium sulfate (DSS). The apple oligogalactan (AOG) was highly effective against intestinal toxicities and carcinogenesis and decreased the elevated levels of TLR4 and tumor necrosis factor-α (TNF-α) induced by inflammation in vivo in this model system. In vitro studies, AOG alone only slightly increased the levels of protein expression and messenger RNA of TLR4, phosphorylation of IκBα and production of TNF-α in HT-29 cells. However, AOG significantly decreased the elevation of all the biomarkers induced by LPS when it was combined with LPS. The effect of AOG may be related to membrane internalization and redistribution of TLR4 from cell membrane to cytoplasm. AOG is active against inflammation and carcinogenesis through targeting LPS/TLR4/NF-κB pathway. Both AOG and LPS are agonists of TLR4 for sharing the same ligand but AOG has a much lower intrinsic activity than that of LPS. AOG may be useful for treatment of colitis and prevention of carcinogenesis in the clinics.

Amitriptyline converts non-responders into responders to low-frequency electroacupuncture-induced analgesia in rats.

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Fais, Rafael S; Reis, G M; Rossaneis, A C; Silveira, J W S; Dias, Q M; Prado, W A

2012-07-26

The purpose of this study was to examine whether the use of intraperitoneal or intrathecal amitriptyline combined with electroacupuncture modifies the tail-flick reflex and incision pain in rats that normally do not have analgesia to electroacupuncture in the tail-flick test (non-responder rats). Changes in the nociceptive threshold of intraperitoneal or intrathecal saline- or amitriptyline-treated non-responder rats were evaluated using the tail-flick or incision pain tests before, during and after a 20-min period of electroacupuncture, applied at 2 Hz to the Zusanli and Sanynjiao acupoints. Amitriptyline was used at doses of 0.8 mg/kg or 30 μg/kg by intraperitoneal or intrathecal route, respectively. At these doses, amitriptyline has no effect against thermal or incision pain in rats. Rats selected as non-responders to the analgesic effect of electroacupuncture 2 Hz in tail-flick and incision pain tests become responders after an intraperitoneal or intrathecal injection of amitriptyline. Amitriptyline converts non-responder rats to rats that respond to electroacupuncture with analgesia in a model of thermal phasic pain and anti-hyperalgesia in a model of incision pain. Copyright © 2012 Elsevier Inc. All rights reserved.

The Structural Basis for Endotoxin-induced Allosteric Regulation of the Toll-like Receptor 4 (TLR4) Innate Immune Receptor*

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Paramo, Teresa; Piggot, Thomas J.; Bryant, Clare E.; Bond, Peter J.

2013-01-01

As part of the innate immune system, Toll-like receptor 4 (TLR4) recognizes bacterial cell surface lipopolysaccharide (LPS) by forming a complex with a lipid-binding co-receptor, MD-2. In the presence of agonist, TLR4·MD-2 dimerizes to form an active receptor complex, leading to initiation of intracellular inflammatory signals. TLR4 is of great biomedical interest, but its pharmacological manipulation is complicated because even subtle variations in the structure of LPS can profoundly impact the resultant immunological response. Here, we use atomically detailed molecular simulations to gain insights into the nature of the molecular signaling mechanism. We first demonstrate that MD-2 is extraordinarily flexible. The “clamshell-like” motions of its β-cup fold enable it to sensitively match the volume of its hydrophobic cavity to the size and shape of the bound lipid moiety. We show that MD-2 allosterically transmits this conformational plasticity, in a ligand-dependent manner, to a phenylalanine residue (Phe-126) at the cavity mouth previously implicated in TLR4 activation. Remarkably, within the receptor complex, we observe spontaneous transitions between active and inactive signaling states of Phe-126, and we confirm that Phe-126 is indeed the “molecular switch” in endotoxic signaling. PMID:24178299

The structural basis for endotoxin-induced allosteric regulation of the Toll-like receptor 4 (TLR4) innate immune receptor.

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Paramo, Teresa; Piggot, Thomas J; Bryant, Clare E; Bond, Peter J

2013-12-20

As part of the innate immune system, Toll-like receptor 4 (TLR4) recognizes bacterial cell surface lipopolysaccharide (LPS) by forming a complex with a lipid-binding co-receptor, MD-2. In the presence of agonist, TLR4·MD-2 dimerizes to form an active receptor complex, leading to initiation of intracellular inflammatory signals. TLR4 is of great biomedical interest, but its pharmacological manipulation is complicated because even subtle variations in the structure of LPS can profoundly impact the resultant immunological response. Here, we use atomically detailed molecular simulations to gain insights into the nature of the molecular signaling mechanism. We first demonstrate that MD-2 is extraordinarily flexible. The "clamshell-like" motions of its β-cup fold enable it to sensitively match the volume of its hydrophobic cavity to the size and shape of the bound lipid moiety. We show that MD-2 allosterically transmits this conformational plasticity, in a ligand-dependent manner, to a phenylalanine residue (Phe-126) at the cavity mouth previously implicated in TLR4 activation. Remarkably, within the receptor complex, we observe spontaneous transitions between active and inactive signaling states of Phe-126, and we confirm that Phe-126 is indeed the "molecular switch" in endotoxic signaling.

Poly-thymidine oligonucleotides mediate activation of murine glial cells primarily through TLR7, not TLR8.

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Min Du

Full Text Available The functional role of murine TLR8 in the inflammatory response of the central nervous system (CNS remains unclear. Murine TLR8 does not appear to respond to human TLR7/8 agonists, due to a five amino acid deletion in the ectodomain. However, recent studies have suggested that murine TLR8 may be stimulated by alternate ligands, which include vaccinia virus DNA, phosphothioate oligodeoxynucleotides (ODNs or the combination of phosphothioate poly-thymidine oligonucleotides (pT-ODNs with TLR7/8 agonists. In the current study, we analyzed the ability of pT-ODNs to induce activation of murine glial cells in the presence or absence of TLR7/8 agonists. We found that TLR7/8 agonists induced the expression of glial cell activation markers and induced the production of multiple proinflammatory cytokines and chemokines in mixed glial cultures. In contrast, pT-ODNs alone induced only low level expression of two cytokines, CCL2 and CXCL10. The combination of pT-ODNs along with TLR7/8 agonists induced a synergistic response with substantially higher levels of proinflammatory cytokines and chemokines compared to CL075. This enhancement was not due to cellular uptake of the agonist, indicating that the pT-ODN enhancement of cytokine responses was due to effects on an intracellular process. Interestingly, this response was also not due to synergistic stimulation of both TLR7 and TLR8, as the loss of TLR7 abolished the activation of glial cells and cytokine production. Thus, pT-ODNs act in synergy with TLR7/8 agonists to induce strong TLR7-dependent cytokine production in glial cells, suggesting that the combination of pT-ODNs with TLR7 agonists may be a useful mechanism to induce pronounced glial activation in the CNS.

Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation

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Lindenmaier Werner

2010-04-01

Full Text Available Abstract Background Toll-like receptor (TLR 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies are applied to block translocation of secreted and cell surface molecules from the ER to the cell surface resulting in functional inhibition of the target protein. Here we describe generation and application of a functional anti-TLR2 ER intrabody (αT2ib which was generated from an antagonistic monoclonal antibody (mAb towards human and murine TLR2 (T2.5 to inhibit the function of TLR2. αT2ib is a scFv fragment comprising the variable domain of the heavy chain and the variable domain of the light chain of mAb T2.5 linked together by a synthetic (Gly4Ser3 amino acid sequence. Results Coexpression of αT2ib and mouse TLR2 in HEK293 cells led to efficient retention and accumulation of TLR2 inside the ER compartment. Co-immunoprecipitation of human TLR2 with αT2ib indicated interaction of αT2ib with its cognate antigen within cells. αT2ib inhibited NF-κB driven reporter gene activation via TLR2 but not through TLR3, TLR4, or TLR9 if coexpressed in HEK293 cells. Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding αT2ib into HEK293 cells demonstrated high efficiency of the TLR2-αT2ib interaction. The αT2ib open reading frame was integrated into an adenoviral cosmid vector for production of recombinant adenovirus (AdV-αT2ib. Transduction with AdVαT2ib specifically inhibited TLR2 surface expression of murine RAW264.7 and primary macrophages derived from bone marrow (BMM. Furthermore, TLR2 activation dependent TNFα mRNA accumulation, as well

Amitriptyline and intraoral devices for migraine prevention: a randomized comparative trial

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Marco A. D. Bruno

Full Text Available ABSTRACT Objectives: Nonpharmacological treatments, such as the Nociceptive Trigeminal Inhibition Tension Suppression System (NTI-tss, are approved for migraine prophylaxis. We aimed at evaluating the effectiveness of the NTI-tss and to compare its efficacy with amitriptyline and with a sham intraoral device in the preventive treatment of migraine. Methods: Consecutive patients with migraine were randomized to receive 25 mg of amitriptyline/day (n = 34, NTI-tss (n = 33 and a non-occlusal splint (n = 30. The headache frequency was evaluated at six and 12 weeks. Results: The amitriptyline group showed, respectively, 60% and 64% reduction in attack frequency at six and 12 weeks (P = 0.000. In the NTI-tss and non-occlusal splint groups, reduction was 39% and 30%, respectively, at six weeks and 48% for both groups at 12 weeks. Conclusions: Amitriptyline proved superior to the NTI-tss and the non-occlusal splint. Despite its approval by the United States Food and Drug Administration, the NTI-tss was not superior to a sham device.

Development of a novel severe triple allergen asthma model in mice which is resistant to dexamethasone and partially resistant to TLR7 and TLR9 agonist treatment.

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Matthias J Duechs

Full Text Available Severe asthma is characterised by persistent inflammation, hyperreactivity and remodeling of the airways. No efficient treatment is available, this is particularly the case for steroid resistant phenotypes. Our aim therefore was to develop a preclinical model showing characteristics of severe human asthma including steroid insensitivity. Mice were first sensitized with ovalbumin, extracts of cockroach or house dust mite followed by a challenge period of seven weeks. Further to this, an additional group of mice was sensitized with all three allergens and then challenged with allergen alternating weekly between allergens. All three allergens applied separately to the mice induced comparably strong Th2-type airway inflammation, airway hyperreactivity and airway remodeling, which was characterised by fibrosis and increased smooth muscle thickness. In contrast, application of all three allergens together resulted in a greater Th2 response and increased airway hyperreactivity and a stronger albeit not significant remodeling phenotype compared to using HDM or CRA. In this triple allergen model dexamethasone application, during the last 4 weeks of challenge, showed no suppressive effects on any of these parameters in this model. In contrast, both TLR7 agonist resiquimod and TLR9 agonist CpG-ODN reduced allergen-specific IgE, eosinophils, and collagen I in the lungs. The TLR9 agonist also reduced IL-4 and IL-5 whilst increasing IFN-γ and strongly IL-10 levels in the lungs, effects not seen with the TLR7 agonist. However, neither TLR agonist had any effect on airway hyperreactivity and airway smooth muscle mass. In conclusion we have developed a severe asthma model, which is steroid resistant and only partially sensitive to TLR7 and TLR9 agonist treatment. This model may be particular useful to test new potential therapeutics aiming at treating steroid resistant asthma in humans and investigating the underlying mechanisms responsible for steroid

Polymorphisms at Locus 4p14 of Toll-Like Receptors TLR-1 and TLR-10 Confer Susceptibility to Gastric Carcinoma in Helicobacter pylori Infection.

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M Ravishankar Ram

Full Text Available Helicobacter pylori (H. pylori -induced gastric inflammation impacts the functions of leptin- and ghrelin-producing cells in the gastroduodenum. Inflammation resulting from H. pylori sensing via Toll-like receptors (TLRs and the associated downstream signaling largely remain ambiguous. Here, we investigated the role of gut hormones, pro-inflammatory cytokines and single nucleotide polymorphisms (SNPs associated with TLR 4p14 in H. pylori disease in 30 subjects with non-ulcer dyspepsia (NUD, 40 with peptic ulcer disease (PUD and 15 with gastric cancer (GC subjects positive and negative for H. pylori infection. The level of pro-inflammatory cytokines was directly proportional to the severity of gastritis, and disease status influenced the levels of gut hormones and pro-inflammatory cytokines. TLR-1 SNPs rs4833095 and TLR-10 SNPs rs10004195 and were directly associated with H. pylori disease, and were up-regulated in the presence of H. pylori in a genotype-independent manner. We concluded that TLR-1 rs4833095 and TLR10 rs10004195 confer susceptibility to development of gastroduodenal disease, especially GC in H.pylori disease.

TLR4, NOD1 and NOD2 Mediate Immune Recognition of Putative Newly-Identified Periodontal Pathogens

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Schaff, Riley A.; Hao, Jie; Morelli, Thiago; Kinney, Janet S.; Gerow, Elizabeth; Sheridan, Rachel; Rodrigues, Vinicius; Paster, Bruce J.; Inohara, Naohiro; Giannobile, William V.

2015-01-01

SUMMARY Periodontitis is a polymicrobial inflammatory disease that results from the interaction between the oral microbiota and the host immunity. While the innate immune response is important for disease initiation and progression, the innate immune receptors that recognize both classical and putative periodontal pathogens that elicit an immune response have not been elucidated. By using the Human Oral Microbe Identification Microarray (HOMIM), we identified multiple predominant oral bacterial species in human plaque biofilm that strongly associate with severe periodontitis. Ten of the identified species were evaluated in greater depth, 6 being classical pathogens and 4 putative novel pathogens. Using human peripheral blood monocytes (HPBM) and murine bone marrow–derived macrophages (BMDM) from wild-type (WT) and toll-like receptor (TLR)-specific and MyD88 knockouts (KOs), we demonstrated that heat-killed Campylobacter concisus, Campylobacter rectus, Selenomonas infelix, Porphyromonas endodontalis, Porphyromonas gingivalis, and Tannerella forsythia mediate high immunostimulatory activity. C. concisus, C. rectus, and S. infelix exhibited robust TLR4 stimulatory activity. Studies using mesothelial cells from WT and NOD1-specific KOs and NOD2-expressing human embryonic kidney (HEK) cells demonstrated that Eubacterium saphenum, Eubacterium nodatum and Filifactor alocis exhibit robust NOD1 stimulatory activity, and that Porphyromonas endodontalis and Parvimonas micra have the highest NOD2-stimulatory activity. These studies allowed us to provide important evidence on newly-identified putative pathogens in periodontal disease pathogenesis showing that these bacteria exhibit different immunostimulatory activity via TLR4, NOD1, and NOD2 (Clinicaltrials.gov NCT01154855). PMID:26177212

A Brief Review of the Pharmacology of Amitriptyline and Clinical Outcomes in Treating Fibromyalgia

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Kim Lawson

2017-05-01

Full Text Available Fibromyalgia is a complex chronic condition characterized by pain, physical fatigue, sleep disorder and cognitive impairment. Evidence-based guidelines recommend antidepressants as treatments of fibromyalgia where tricyclics are often considered to have the greatest efficacy, with amitriptyline often being a first-line treatment. Amitriptyline evokes a preferential reduction in pain and fatigue of fibromyalgia, and in the Fibromyalgia Impact Questionnaire (FIQ score, which is a quality of life assessment. The multimodal profile of the mechanisms of action of amitriptyline include monoamine reuptake inhibition, receptor modulation and ion channel modulation. Several of the actions of amitriptyline on multiple nociceptive and sensory processes at central and peripheral locations have the potential to act cumulatively to suppress the characteristic symptoms of fibromyalgia. Greater understanding of the role of these mechanisms of action of amitriptyline could provide further clues to the pathophysiology of fibromyalgia and to a preferable pharmacological profile for future drug development.

A Brief Review of the Pharmacology of Amitriptyline and Clinical Outcomes in Treating Fibromyalgia

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Lawson, Kim

2017-01-01

Fibromyalgia is a complex chronic condition characterized by pain, physical fatigue, sleep disorder and cognitive impairment. Evidence-based guidelines recommend antidepressants as treatments of fibromyalgia where tricyclics are often considered to have the greatest efficacy, with amitriptyline often being a first-line treatment. Amitriptyline evokes a preferential reduction in pain and fatigue of fibromyalgia, and in the Fibromyalgia Impact Questionnaire (FIQ) score, which is a quality of life assessment. The multimodal profile of the mechanisms of action of amitriptyline include monoamine reuptake inhibition, receptor modulation and ion channel modulation. Several of the actions of amitriptyline on multiple nociceptive and sensory processes at central and peripheral locations have the potential to act cumulatively to suppress the characteristic symptoms of fibromyalgia. Greater understanding of the role of these mechanisms of action of amitriptyline could provide further clues to the pathophysiology of fibromyalgia and to a preferable pharmacological profile for future drug development. PMID:28536367

P-MAPA immunotherapy potentiates the effect of cisplatin on serous ovarian carcinoma through targeting TLR4 signaling.

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de Almeida Chuffa, Luiz Gustavo; de Moura Ferreira, Grazielle; Lupi, Luiz Antonio; da Silva Nunes, Iseu; Fávaro, Wagner José

2018-01-17

Toll-like receptors (TLRs) are transmembrane proteins expressed on the surface of ovarian cancer (OC) and immune cells. Identifying the specific roles of the TLR-mediated signaling pathways in OC cells is important to guide new treatments. Because immunotherapies have emerged as the adjuvant treatment for patients with OC, we investigated the effect of a promising immunotherapeutic strategy based on protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride (P-MAPA) combined with cisplatin (CIS) on the TLR2 and TLR4 signaling pathways via myeloid differentiation factor 88 (MyD88) and TLR-associated activator of interferon (TRIF) in an in vivo model of OC. Tumors were chemically induced by a single injection of 100 μg of 7,12-dimethylbenz(a)anthracene (DMBA) directly under the left ovarian bursa in Fischer 344 rats. After the rats developed serous papillary OC, they were given P-MAPA, CIS or the combination P-MAPA+CIS as therapies. To understand the effects of the treatments, we assessed the tumor size, histopathology, and the TLR2- and TLR4-mediated inflammatory responses. Although CIS therapy was more effective than P-MAPA in reducing the tumor size, P-MAPA immunotherapy significantly increased the expressions of TLR2 and TLR4. More importantly, the combination of P-MAPA with CIS showed a greater survival rate compared to CIS alone, and exhibited a significant reduction in tumor volume compared to P-MAPA alone. The combination therapy also promoted the increase in the levels of the following OC-related proteins: TLR4, MyD88, TRIF, inhibitor of phosphorylated NF-kB alpha (p-IkBα), and nuclear factor kappa B (NF-kB p65) in both cytoplasmic and nuclear sites. While P-MAPA had no apparent effect on tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6, it seems to increase interferon-γ (IFN-γ), which may induce the Thelper (Th1)-mediated immune response. Collectively, our results suggest that P-MAPA immunotherapy combined with cisplatin

β2-glycoprotein I, lipopolysaccharide and endothelial TLR4: three players in the two hit theory for anti-phospholipid-mediated thrombosis.

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Raschi, Elena; Chighizola, Cecilia B; Grossi, Claudia; Ronda, Nicoletta; Gatti, Rita; Meroni, Pier Luigi; Borghi, M Orietta

2014-12-01

The thrombogenic effect of β2-glycoprotein I (β2GPI)-dependent anti-phospholipid antibodies (aPL) in animal models was found to be LPS dependent. Since β2GPI behaves as LPS scavenger, LPS/β2GPI complex was suggested to account for in vitro cell activation through LPS/TLR4 involvement being LPS the actual bridge ligand between β2GPI and TLR4 at least in monocytes/macrophages. However, no definite information is available on the interaction among β2GPI, LPS and endothelial TLR4 in spite of the main role of endothelial cells (EC) in clotting. To analyse at the endothelial level the need of LPS, we investigated the in vitro interaction of β2GPI with endothelial TLR4 and we assessed the role of LPS in such an interaction. To do this, we evaluated the direct binding and internalization of β2GPI by confocal microscopy in living TLR4-MD2 transfected CHO cells (CHO/TLR4-MD2) and β2GPI binding to CHO/TLR4-MD2 cells and human umbilical cord vein EC (HUVEC) by flow cytometry and cell-ELISA using anti-β2GPI monoclonal antibodies in the absence or presence of various concentrations of exogenous LPS. To further investigate the role of TLR4, we performed anti-β2GPI antibody binding and adhesion molecule up-regulation in TLR4-silenced HUVEC. Confocal microscopy studies show that β2GPI does interact with TLR4 at the cell membrane and is internalized in cytoplasmic granules in CHO/TLR4-MD2 cells. β2GPI binding to CHO/TLR4-MD2 cells and HUVEC is also confirmed by flow cytometry and cell-ELISA, respectively. The interaction between β2GPI and TLR4 is confirmed by the reduction of anti-β2GPI antibody binding and by the up-regulation of E-selectin or ICAM-1 by TLR4 silencing in HUVEC. β2GPI binding is not affected by LPS at concentrations comparable to those found in both β2GPI and antibody preparations. Only higher amount of LPS that can activate EC and up-regulate TLR4 expression are found to increase the binding. Our findings demonstrate that β2GPI interacts

The TLR4 D299G and T399I SNPs are constitutively active to up-regulate expression of Trif-dependent genes.

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Georgina L Hold

Full Text Available Dysregulated Toll-Like Receptor (TLR signalling and genetic polymorphisms in these proteins are linked to many human diseases. We investigated TLR4 functional variants D299G and T399I to assess the impact on LPS-induced responsiveness in comparison to wild-type TLR4. The mechanism by which this occurs in unclear as these SNPs do not lie within the lipid A binding domain or dimerisation sites of the LPS-TLR4/MD2 receptor complexes. Transfection of TLR4D299G, TLR4T399I or TLR4D299G. T399I into HEK cells resulted in constitutive activation of an NF-κB reporter gene and a blunting of the LPS-induced reporter activation compared to WT-TLR4. Unstimulated human monocyte/macrophages, from patients with the D299G and T399I SNPs demonstrated a downregulation of many genes, particularly Tram/Trif signalling pathway constitutents compared to the TLR4 wild-type subjects supporting the concept of basal receptor activity. Monocyte/macrophages from carriers of the TLR4 D299G and T399I polymorphisms stimulated with LPS showed >6 fold lower levels of NF-κB and ∼12 fold higher IFN-β gene expression levels compared to wild-type subjects (P<0.05; MWU test and dramatically altered resultant cytokine profiles. We conclude that these TLR4 SNPs affect constitutive receptor activity which impacts on the hosts ability to respond to LPS challenge leading to a dysregulated sub-optimal immune response to infection.

Expression of TLR4 in Non-Small Cell Lung Cancer Is Associated with PD-L1 and Poor Prognosis in Patients Receiving Pulmonectomy

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Xiubao Ren

2017-04-01

Full Text Available Currently, the effect of inflammation on tumorigenesis and progression has been widely noted. As a member of pattern recognition receptors, toll-like receptor 4 (TLR4 plays a pivotal role in tumor immune microenvironment and has been increasingly investigated. In the present study, we evaluated TLR4 expression and its association with programmed cell death ligand 1 (PD-L1 in non-small cell lung cancer (NSCLC tissues and assessed the predicting value of TLR4 on postoperative outcome. A total of 126 NSCLC patients receiving complete pulmonary resection and systematic lymph node dissection between April 2008 and August 2014 were enrolled. All the patients had integrated clinicopathological records and follow-up data. TLR4 and PD-L1 expression on NSCLC samples were determined by immunohistochemistry, and serum soluble TLR4 (sTLR4 levels were measured by enzyme-linked immunosorbent assay. Results showed that TLR4 expression level in cancer tissue was significantly higher than that in para-cancer tissue. Elevated TLR4 expression was significantly associated with histological type (adenocarcinoma higher than squamous cell carcinoma, P = 0.041, increased clinical TNM stage (P < 0.001, and presence of lymphatic invasion (P < 0.001. Besides, TLR4 expression level in cancer samples was inversely correlated with serum sTLR4 level in patients with early-stage NSCLC (r = −0.485, P = 0.003. TLR4 expression level was also positively correlated with the PD-L1 expression level (r = 0.545, P < 0.0001. Multivariate analysis showed that expression level of TLR4 was an independent prognostic factor and TLR4 overexpression indicated a poor overall survival and disease-free survival. Taken together, we conclude that expression of TLR4 in lung cancer is associated with PD-L1 and could predict the outcome of patients with NSCLC receiving pulmonary resection for cancer.

TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role in monocyte adhesion to vascular endothelium.

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Seung Jin Lee

Full Text Available Toll-like receptor 4 (TLR4 is known to mediate monocyte adhesion to endothelial cells, however, its role on the expression of monocyte adhesion molecules is unclear. In the present study, we investigated the role of TLR4 on the expression of monocyte adhesion molecules, and determined the functional role of TLR4-induced adhesion molecules on monocyte adhesion to endothelial cells. When THP-1 monocytes were stimulated with Kdo2-Lipid A (KLA, a specific TLR4 agonist, Mac-1 expression was markedly increased in association with an increased adhesion of monocytes to endothelial cells. These were attenuated by anti-Mac-1 antibody, suggesting a functional role of TLR4-induced Mac-1 on monocyte adhesion to endothelial cells. In monocytes treated with MK886, a 5-lipoxygenase (LO inhibitor, both Mac-1 expression and monocyte adhesion to endothelial cells induced by KLA were markedly attenuated. Moreover, KLA increased the expression of mRNA and protein of 5-LO, suggesting a pivotal role of 5-LO on these processes. In in vivo studies, KLA increased monocyte adhesion to aortic endothelium of wild-type (WT mice, which was attenuated in WT mice treated with anti-Mac-1 antibody as well as in TLR4-deficient mice. Taken together, TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role on monocyte adhesion to vascular endothelium, leading to increased foam cell formation in the development of atherosclerosis.

Genetic Diversity of IFγ, IL1β, TLR2, and TLR8 Loci in Pulmonary Tuberculosis in Kazakhstan

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Dauren Yerezhepov

2014-12-01

Full Text Available Introduction. Tuberculosis (TB is caused by bacterium Mycobacterium tuberculosis (MTB, and according to the WHO, up to 30% of world population is infected with latent TB. Pathogenesis of TB is multifactorial, and its development depends on environmental, social, microbial, and genetic factors of both the bacterium and the host. The number of TB cases in Kazakhstan has decreased in the past decade, but multidrug-resistant (MDR TB cases are dramatically increasing. Polymorphisms in genes responsible for immune response have been associated with TB susceptibility. The objective of this study was to investigate the risk of developing pulmonary TB (PTB associated with polymorphisms in several inflammatory pathway genes among Kazakhstani population.Methods. 703 participants from 3 regions of Kazakhstan were recruited for a case-control study. 251 participants had pulmonary TB (PTB, and 452 were healthy controls (HC. Males and females represented 42.39% and 57.61%, respectively. Of all participants, 67.4% were Kazakhs, 22.8% Russians, 3.4% Ukrainians, and 6.4% were of other origins. Clinical and epidemiological data were collected from medical records, interviews, and questionnaires. DNA samples were genotyped using TaqMan assay on 4 polymorphisms: IFNγ (rs2430561 and IL1β (rs16944, TLR2 (rs5743708 and TLR8 (rs3764880. Statistical data was analyzed using SPSS 19.Results. Genotyping by IFγ, IL1β, TLR2 showed no significant association with PTB susceptibility (p > 0.05. TLR8 genotype A/G was significantly higher in females (F/M – 41.5%/1.3% and G/G in males (M/F – 49%/20.7% (χ2=161.43, p < 0.001. A significantly increased risk of PTB development was observed for TLR A/G with an adjusted OR of 1.48 (95%, CI: 0.96 - 2.28, and a protective feature was revealed for TLR8 G/G genotype (OR: 0.81, 95%, CI: 0.56 - 1.16, p = 0.024. Additional grouping by gender revealed that TLR8 G/G contributes as protective genotype (OR: 1.83, 95%, CI: 1.18 - 2.83, p

Interactions of Notch1 and TLR4 signaling pathways in DRG neurons of in vivo and in vitro models of diabetic neuropathy.

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Chen, Tianhua; Li, Hao; Yin, Yiting; Zhang, Yuanpin; Liu, Zhen; Liu, Huaxiang

2017-11-02

Understanding the interactions between Notch1 and toll-like receptor 4 (TLR4) signaling pathways in the development of diabetic peripheral neuropathy may lead to interpretation of the mechanisms and novel approaches for preventing diabetic neuropathic pain. In the present study, the interactions between Notch1 and TLR4 signaling pathways were investigated by using dorsal root ganglion (DRG) from diabetic neuropathic pain rats and cultured DRG neurons under high glucose challenge. The results showed that high glucose induced not only Notch1 mRNA, HES1 mRNA, and TLR4 mRNA expression, but also Notch1 intracellular domain (NICD1) and TLR4 protein expression in DRG neurons. The proportion of NICD1-immunoreactive (IR) and TLR4-IR neurons in DRG cultures was also increased after high glucose challenge. The above alterations could be partially reversed by inhibition of either Notch1 or TLR4 signaling pathway. Inhibition of either Notch1 or TLR4 signaling pathway could improve mechanical allodynia and thermal hyperalgesia thresholds. Inhibition of Notch1 or TLR4 signaling also decreased tumor necrosis factor-α (TNF-α) levels in DRG from diabetic neuropathic rats. These data imply that the interaction between Notch1 and TLR4 signaling pathways is one of the important mechanisms in the development or progression of diabetic neuropathy.

Influence of heparin on the assay of amitriptyline, clomipramine, and their metabolites

NARCIS (Netherlands)

Levering, S.C.M.; Oostelbos, M.C.J.M.; Toll, P.J.M.M.; Loonen, A.J.M.

1996-01-01

In this study the effect of the use of lithium heparin containers on the plasma levels of amitriptyline, clomipramine, and their metabolites was investigated. Twenty-five patients (10 men and 15 women, mean age 51.8 ± 14.9 years) taking either amitriptyline or clomipramine in a daily dosage varying

Challenging the neuronal MIBG uptake by pharmacological intervention: effect of a single dose of oral amitriptyline on regional cardiac MIBG uptake

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Estorch, Montserrat; Carrio, Ignasi; Mena, Esther; Flotats, Albert; Camacho, Valle; Fuertes, Jordi [Autonomous University of Barcelona, Department of Nuclear Medicine, Hospital Sant Pau, Barcelona (Spain); Kulisewsky, Jaume [Autonomous University of Barcelona, Department of Neurology, Hospital Sant Pau, Barcelona (Spain); Narula, Jagat [Irvine College of Medicine, Division of Cardiology, University of California, Irvine, CA (United States)

2004-12-01

Imaging with metaiodobenzylguanidine (MIBG) is used for the assessment of neuronal dysfunction in various cardiovascular disorders. Although valuable information is obtained by resting MIBG imaging, it is conceivable that competitive interference with the re-uptake mechanism would exaggerate MIBG defects and might unmask subclinical neuronal dysfunction. Tricyclic antidepressants, such as amitriptyline, have been reported to significantly increase cardiac MIBG washout and inhibit uptake into presynaptic neurons. This study was undertaken to assess whether a single oral dose of amitriptyline could influence cardiac MIBG distribution. Six patients (aged 62-81 years; four males, two females) who had demonstrated a normal cardiac MIBG scan during work-up for movement disorders were studied. The patients underwent a second {sup 123}I-MIBG study after oral administration of 25 mg amitriptyline within 1 week. Single-photon emission computed tomography images were acquired at 4 h to assess the regional distribution of MIBG, after generation of polar maps and employing a 20-segment model. Mean percentage of peak activity was calculated for each segment at rest and after amitriptyline administration. After amitriptyline administration, there was a decrease in regional MIBG uptake in 10{+-}4 segments per patient [62/120 segments (52%): 37 segments with a 5-10% decrease, 25 segments with a >10% decrease]. This change was statistically significant in lateral (P=0.003), apical (P<0.0001) and inferior (P=0.03) regions. A single oral dose of amitriptyline can induce changes in the uptake and retention of cardiac MIBG, indicating the feasibility of use of pharmacological intervention in cardiac neurotransmission imaging. (orig.)

Platelet-activating factor induces TLR4 expression in intestinal epithelial cells: implication for the pathogenesis of necrotizing enterocolitis.

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Antoine Soliman

Full Text Available Necrotizing enterocolitis (NEC is a leading cause of morbidity and mortality in neonatal intensive care units, however its pathogenesis is not completely understood. We have previously shown that platelet activating factor (PAF, bacteria and TLR4 are all important factors in the development of NEC. Given that Toll-like receptors (TLRs are expressed at low levels in enterocytes of the mature gastrointestinal tract, but were shown to be aberrantly over-expressed in enterocytes in experimental NEC, we examined the regulation of TLR4 expression and signaling by PAF in intestinal epithelial cells using human and mouse in vitro cell lines, and the ex vivo rat intestinal loop model. In intestinal epithelial cell (IEC lines, PAF stimulation yielded upregulation of both TLR4 mRNA and protein expression and led to increased IL-8 secretion following stimulation with LPS (in an otherwise LPS minimally responsive cell line. PAF stimulation resulted in increased human TLR4 promoter activation in a dose dependent manner. Western blotting and immunohistochemical analysis showed PAF induced STAT3 phosphorylation and nuclear translocation in IEC, and PAF-induced TLR4 expression was inhibited by STAT3 and NFκB Inhibitors. Our findings provide evidence for a mechanism by which PAF augments inflammation in the intestinal epithelium through abnormal TLR4 upregulation, thereby contributing to the intestinal injury of NEC.

Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy.

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Santana, Nadja de Lima; Rêgo, Jamile Leão; Oliveira, Joyce Moura; Almeida, Lucas Frederico de; Braz, Marcos; Machado, Lídia Maria Medeiros; Machado, Paulo Roberto Lima; Castellucci, Léa Cristina

2017-04-01

Leprosy or hansen's disease is a spectral disease whose clinical forms mostly depends on host's immune and genetic factors. Different Toll-like receptors (TLR) variants have been described associated with leprosy, but with some lack of replication across different populations. To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551), TLR2 (rs7656411, rs3804099) and TLR4 (rs1927914, rs1927911). A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA) test in the serum of a subgroup of patients with and without leprosy reactions. Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR) = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2). Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host's production of key cytokines and chemokines involved in the pathogenesis of this disease.

Desert dust induces TLR signaling to trigger Th2-dominant lung allergic inflammation via a MyD88-dependent signaling pathway

International Nuclear Information System (INIS)

He, Miao; Ichinose, Takamichi; Song, Yuan; Yoshida, Yasuhiro; Bekki, Kanae; Arashidani, Keiichi; Yoshida, Seiichi; Nishikawa, Masataka; Takano, Hirohisa; Shibamoto, Takayuki; Sun, Guifan

2016-01-01

Asian sand dust (ASD) is known to exacerbate asthma, although its mechanism is not yet well understood. In this study, when the effects on inflammatory response by LPS present in ASD was investigated by measuring the gene expression of cytokines and chemokines in RAW264.7 cells treated with ASD and/or polymyxin B (PMB), the ASD effects were attenuated by PMB, but not completely. When an in vitro study was performed using bone marrow-derived macrophages (BMDMs) from WT, TLR2 −/− , TLR4 −/− , and MyD88 −/− BALB/c mice and BMDMs from WT, TLR2 −/− , TLR4 −/− , TLR2/4 −/− , TLR7/9 −/− , and MyD88 −/− C57BL/6J mice, cytokine (IL-6, IL-12) production in BMDMs was higher in ASD-stimulated TLR2 −/− cells than in TLR4 −/− cells, whereas it was lower or undetectable in TLR2/4 −/− and MyD88 −/− cells. These results suggest that ASD causes cytokine production predominantly in a TLR4/MyD88-dependent pathway. When WT and TLRs 2 −/− , 4 −/− , and MyD88 −/− BALB/c mice were intratracheally challenged with OVA and/or ASD, ASD caused exacerbation of lung eosinophilia along with Th2 cytokine and eosinophil-relevant chemokine production. Serum OVA-specific IgE and IgG1 similar to WT was observed in TLRs 2 −/− , 4 −/− mice, but not in MyD88 −/− mice. The Th2 responses in TLR2 −/− mice were attenuated remarkably by PMB. These results indicate that ASD exacerbates lung eosinophilia in a MyD88-dependent pathway. TLRs 2 and 4 signaling may be important in the increase in lung eosinophilia. Also, the TLR4 ligand LPS and TLR2 ligand like β-glucan may be strong candidates for exacerbation of lung eosinophilia. - Highlights: • ASD enhanced Th2 response in TLR2 −/− , TLR4 −/− and WT mice, but not in MyD88 −/− . • Th2 responses in TLR2 −/− mice were attenuated by LPS inhibitor polymyxin B. • TLR2 and TLR4 signaling is important in allergic lung disease aggravation by ASD. • MyD88 is the key

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways

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Lena Seifert

2015-12-01

Full Text Available Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1–/– mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis.

Vitamin K2 can suppress the expression of Toll-like receptor 2 (TLR2) and TLR4, and inhibit calcification of aortic intima in ApoE-/- mice as well as smooth muscle cells.

Science.gov (United States)

Wang, Zhaojun; Wang, Zhongqun; Zhu, Jie; Long, Xinguang; Yan, Jinchuan

2018-02-01

Background and objectives Vascular calcification is a common complication in atherosclerosis. Accumulating evidence showed that Toll-like receptors (TLRs) mediate pro-inflammatory and atherosclerosis. Recent studies demonstrated that vascular calcification is one of the detrimental effects of vitamin K (Vit K) antagonists. However, the effects of Vit K on the expression of TLR2 and 4 and intimal calcification in artery remained unidentified. Methods and results Eighteen ApoE -/- mice were randomly divided into model group, Vit K-treated group, and control group. The mice of model and Vit K-treated group were fed with high-fat diet, while control group mice were fed with normal diet. Mice of Vit K-treated group were administered orally with vitamin K2 (40 mg.kg -1 .day -1 ) for 12 weeks. Twelve weeks later the aortic sections of mice were acquired and stained with hematoxylin and eosin and von Kossa, respectively. Calcium content and activity of alkaline phosphatase (ALP) at aortic tissues were measured. The expression levels of TLR2 and TLR4 in aorta sections were detected by immunohistochemisty and RT-PCR, respectively. The effects of Vit K on cellular calcification were further studied in A7r5 SMCs. Results demonstrated that high-fat diet induced typical atherosclerosis with intimal calcification in ApoE -/- mice, while in Vit K-treated group atherosclerosis and calcium deposits were not serious; Vit K2 also inhibited cellular calcification in A7r5 SMCs. Quantitative analysis showed that calcium and ALP activity at aortic tissues in the Vit K-treated mice were significantly lower than that of the model group ( P < 0.01); Compared to the control group, the expression levels of TLR2 and TLR4 in the model group were significantly higher ( P < 0.05), while in Vit K-treated group the levels of TLR2 and 4 were significantly lower than that in the model group. Furthermore, the content of calcium was positively related to the expression levels of TLR2 and TLR4

TLR4, NOD1 and NOD2 mediate immune recognition of putative newly identified periodontal pathogens.

Science.gov (United States)

Marchesan, Julie; Jiao, Yizu; Schaff, Riley A; Hao, Jie; Morelli, Thiago; Kinney, Janet S; Gerow, Elizabeth; Sheridan, Rachel; Rodrigues, Vinicius; Paster, Bruce J; Inohara, Naohiro; Giannobile, William V

2016-06-01

Periodontitis is a polymicrobial inflammatory disease that results from the interaction between the oral microbiota and the host immunity. Although the innate immune response is important for disease initiation and progression, the innate immune receptors that recognize both classical and putative periodontal pathogens that elicit an immune response have not been elucidated. By using the Human Oral Microbe Identification Microarray (HOMIM), we identified multiple predominant oral bacterial species in human plaque biofilm that strongly associate with severe periodontitis. Ten of the identified species were evaluated in greater depth, six being classical pathogens and four putative novel pathogens. Using human peripheral blood monocytes (HPBM) and murine bone-marrow-derived macrophages (BMDM) from wild-type (WT) and Toll-like receptor (TLR)-specific and MyD88 knockouts (KOs), we demonstrated that heat-killed Campylobacter concisus, Campylobacter rectus, Selenomonas infelix, Porphyromonas endodontalis, Porphyromonas gingivalis, and Tannerella forsythia mediate high immunostimulatory activity. Campylobacter concisus, C. rectus, and S. infelix exhibited robust TLR4 stimulatory activity. Studies using mesothelial cells from WT and NOD1-specific KOs and NOD2-expressing human embryonic kidney cells demonstrated that Eubacterium saphenum, Eubacterium nodatum and Filifactor alocis exhibit robust NOD1 stimulatory activity, and that Porphyromonas endodontalis and Parvimonas micra have the highest NOD2 stimulatory activity. These studies allowed us to provide important evidence on newly identified putative pathogens in periodontal disease pathogenesis showing that these bacteria exhibit different immunostimulatory activity via TLR4, NOD1, and NOD2 (Clinicaltrials.gov NCT01154855). © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Role of TLR4 gene polymorphisms in the colorectal cancer risk ...

African Journals Online (AJOL)

Role of TLR4 gene polymorphisms in the colorectal cancer risk modulation in ethnic Kashmiri population – A case–control study. Saniya Nissar, Aga Syed Sameer, Roohi Rasool, Qurteeba Qadri, Nissar A. Chowdri, Fouzia Rashid ...

Saturated fatty acids enhance TLR4 immune pathways in human trophoblasts.

Science.gov (United States)

Yang, Xiaohua; Haghiac, Maricela; Glazebrook, Patricia; Minium, Judi; Catalano, Patrick M; Hauguel-de Mouzon, Sylvie

2015-09-01

What are the effects of fatty acids on placental inflammatory cytokine with respect to toll-like receptor-4/nuclear factor-kappa B (TLR4/NF-kB)? Exogenous fatty acids induce a pro-inflammatory cytokine response in human placental cells in vitro via activation of TLR4 signaling pathways. The placenta is exposed to changes in circulating maternal fatty acid concentrations throughout pregnancy. Fatty acids are master regulators of innate immune pathways through recruitment of toll-like receptors and activation of cytokine synthesis. Trophoblast cells isolated from 14 normal term human placentas were incubated with long chain fatty acids (FA) of different carbon length and degree of saturation. The expression and secretion of interleukin-6 (IL-6), IL-8 and tumor necrosis factor-alpha (TNF-α) were measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Antibodies against TLR4 ligand binding domain, downstream signaling and anti-p65 NFkB-inhibitor were used to characterize the pathways of FA action. General approach used primary human term trophoblast cell culture. Methods and end-points used real-time quantitative PCR, cytokine measurements, immunohistochemistry, western blots. The long chain saturated fatty acids, stearic and palmitic (PA), stimulated the synthesis as well as the release of TNF-α, IL-6 and IL-8 by trophoblast cells (2- to 6-fold, P acids did not modify cytokine expression significantly. Palmitate-induced inflammatory effects were mediated via TLR4 activation, NF-kB phosphorylation and nuclear translocation. TNF-α protein level was close to the limit of detection in the culture medium even when cells were cultured with PA. These mechanisms open the way to a better understanding of how changes in maternal lipid homeostasis may regulate placental inflammatory status. X.Y. was recipient of fellowship award from West China Second University Hospital, Sichuan University (NIH HD 22965-19). The authors have nothing

Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy

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Nadja de Lima Santana

Full Text Available BACKGROUND Leprosy or hansen’s disease is a spectral disease whose clinical forms mostly depends on host’s immune and genetic factors. Different Toll-like receptors (TLR variants have been described associated with leprosy, but with some lack of replication across different populations. OBJECTIVES To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. METHODS Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551, TLR2 (rs7656411, rs3804099 and TLR4 (rs1927914, rs1927911. A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA test in the serum of a subgroup of patients with and without leprosy reactions. FINDINGS Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2. Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. MAIN CONCLUSIONS All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host’s production of key cytokines and chemokines involved in the pathogenesis of this disease.

Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy

Science.gov (United States)

Santana, Nadja de Lima; Rêgo, Jamile Leão; Oliveira, Joyce Moura; de Almeida, Lucas Frederico; Braz, Marcos; Machado, Lídia Maria Medeiros; Machado, Paulo Roberto Lima; Castellucci, Léa Cristina

2017-01-01

BACKGROUND Leprosy or hansen’s disease is a spectral disease whose clinical forms mostly depends on host’s immune and genetic factors. Different Toll-like receptors (TLR) variants have been described associated with leprosy, but with some lack of replication across different populations. OBJECTIVES To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. METHODS Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551), TLR2 (rs7656411, rs3804099) and TLR4 (rs1927914, rs1927911). A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA) test in the serum of a subgroup of patients with and without leprosy reactions. FINDINGS Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR) = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2). Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. MAIN CONCLUSIONS All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host’s production of key cytokines and chemokines involved in the pathogenesis of this disease. PMID:28327786

Polymorphisms within the Toll-Like Receptor (TLR-2, -4, and -6 Genes in Cattle

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Marco Mariotti

2009-07-01

Full Text Available In mammals, members of the TLR gene family play a primary role in the recognition of pathogen-associated molecular patterns from bacteria, viruses, protozoa and fungi. Recently, cattle TLR genes have been mapped to chromosomes using a radiation hybrid panel. Nucleotide sequences of bovine TLR2, TLR4 and TLR6 genes were screened to identify novel SNPs that can be used in studies of cattle resistance to diseases. In total, 8 SNPs were identified and were submitted to the NCBI dbSNP database. The frequencies of the SNPs were assessed in 16 different bovine European cattle breeds and a phylogenetic analysis carried out to describe the relationships between the breeds. Even if from our analysis the SNPs do not appear located in loci under selection, a deviation of three SNPs from Hardy Weinberg equilibrium was observed, and we hypothesize that some of the polymorphisms may be fixated since many generations. The described variations in immune function related genes will contribute to research on disease response in cattle. In fact, the SNPs can be used in association studies between polymorphisms and cattle resistance to diseases.

Amitriptyline and intraoral devices for migraine prevention: a randomized comparative trial

OpenAIRE

Bruno, Marco A. D.; Krymchantowski, Abouch V.

2018-01-01

ABSTRACT Objectives: Nonpharmacological treatments, such as the Nociceptive Trigeminal Inhibition Tension Suppression System (NTI-tss), are approved for migraine prophylaxis. We aimed at evaluating the effectiveness of the NTI-tss and to compare its efficacy with amitriptyline and with a sham intraoral device in the preventive treatment of migraine. Methods: Consecutive patients with migraine were randomized to receive 25 mg of amitriptyline/day (n = 34), NTI-tss (n = 33) and a non-occlusal...

TLR4-HMGB1 signaling pathway affects the inflammatory reaction of autoimmune myositis by regulating MHC-I.

Science.gov (United States)

Wan, Zemin; Zhang, Xiujuan; Peng, Anping; He, Min; Lei, Zhenhua; Wang, Yunxiu

2016-12-01

To analyze the effects of TLR4 on the expression of the HMGB1, MHC-I and downstream cytokines IL-6 and TNF-α, and to investigate the biological role of the TLR4-HMGB1 signaling pathway in the development of the autoimmune myositis. We built mice models with experimental autoimmune myositis (EAM) and used the inverted screen experiment to measure their muscle endurance; we also examined inflammatory infiltration of muscle tissues after HE staining; and we assessed the expression of MHC-I using immunohistochemistry. In addition, peripheral blood mononuclear cells (PBMC) were extracted and flow cytometry was utilized to detect the effect of IFN-γ on the expression of MHC-I. Furthermore, PBMCs were treated with IFN-γ, anti-TLR4, anti-HMGB1 and anti-MHC-I. Real-time PCR and western blotting were employed to examine the expressions of TLR4, HMGB1 and MHC-I in different groups. The ELISA method was also utilized to detect the expression of the downstream cytokines TNF-α and IL-6. The expressions of TLR4, HMGB1 and MHC-I in muscle tissues from mice with EAM were significantly higher than those in the control group (all Pmyositis inflammation by regulating the expression of MHC-I and other pro-inflammatory cytokines. Copyright © 2016 Elsevier B.V. All rights reserved.

Cloning and SNP screening of TLR4 gene and the association ...

African Journals Online (AJOL)

huis

Human models, in particular, suggest TLR4 to be a candidate gene .... Rapid amplification of cDNA ends (RACE) was performed with a BD SMART™ RACE cDNA .... content (PIC) were calculated with software of POPGENE (Ver. 1.31).

Desert dust induces TLR signaling to trigger Th2-dominant lung allergic inflammation via a MyD88-dependent signaling pathway

Energy Technology Data Exchange (ETDEWEB)

He, Miao, E-mail: hemiao@mail.cmu.edu.cn [Environment and Non-communicable Disease Research Center, School of Public Health, China Medical University, Shenyang 110122 (China); Ichinose, Takamichi, E-mail: ichinose@oita-nhs.ac.jp [Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita 870-1201 (Japan); Song, Yuan; Yoshida, Yasuhiro [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Fukuoka 807-8555 (Japan); Bekki, Kanae [Department of Environmental Health, National Institute of Public Health, Saitama 351-0197 (Japan); Arashidani, Keiichi [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Fukuoka 807-8555 (Japan); Yoshida, Seiichi [Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita 870-1201 (Japan); Nishikawa, Masataka [Environmental Chemistry Division, National Institute for Environmental Studies, Ibaraki 305-8506 (Japan); Takano, Hirohisa [Environmental Health Division, Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8530 (Japan); Shibamoto, Takayuki [Department of Environmental Toxicology, University of California, Davis, CA 95616, USA. (United States); Sun, Guifan [Environment and Non-communicable Disease Research Center, School of Public Health, China Medical University, Shenyang 110122 (China)

2016-04-01

Asian sand dust (ASD) is known to exacerbate asthma, although its mechanism is not yet well understood. In this study, when the effects on inflammatory response by LPS present in ASD was investigated by measuring the gene expression of cytokines and chemokines in RAW264.7 cells treated with ASD and/or polymyxin B (PMB), the ASD effects were attenuated by PMB, but not completely. When an in vitro study was performed using bone marrow-derived macrophages (BMDMs) from WT, TLR2{sup −/−}, TLR4{sup −/−}, and MyD88{sup −/−} BALB/c mice and BMDMs from WT, TLR2{sup −/−}, TLR4{sup −/−}, TLR2/4{sup −/−}, TLR7/9{sup −/−}, and MyD88{sup −/−} C57BL/6J mice, cytokine (IL-6, IL-12) production in BMDMs was higher in ASD-stimulated TLR2{sup −/−} cells than in TLR4{sup −/−} cells, whereas it was lower or undetectable in TLR2/4{sup −/−} and MyD88{sup −/−} cells. These results suggest that ASD causes cytokine production predominantly in a TLR4/MyD88-dependent pathway. When WT and TLRs 2{sup −/−}, 4{sup −/−}, and MyD88{sup −/−} BALB/c mice were intratracheally challenged with OVA and/or ASD, ASD caused exacerbation of lung eosinophilia along with Th2 cytokine and eosinophil-relevant chemokine production. Serum OVA-specific IgE and IgG1 similar to WT was observed in TLRs 2{sup −/−}, 4{sup −/−} mice, but not in MyD88{sup −/−} mice. The Th2 responses in TLR2{sup −/−} mice were attenuated remarkably by PMB. These results indicate that ASD exacerbates lung eosinophilia in a MyD88-dependent pathway. TLRs 2 and 4 signaling may be important in the increase in lung eosinophilia. Also, the TLR4 ligand LPS and TLR2 ligand like β-glucan may be strong candidates for exacerbation of lung eosinophilia. - Highlights: • ASD enhanced Th2 response in TLR2{sup −/−}, TLR4{sup −/−} and WT mice, but not in MyD88{sup −/−}. • Th2 responses in TLR2{sup −/−} mice were attenuated by LPS inhibitor polymyxin B. • TLR2

Decreased Secondary Lesion Growth and Attenuated Immune Response after Traumatic Brain Injury in Tlr2/4−/− Mice

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Sandro M. Krieg

2017-08-01

Full Text Available Danger-associated molecular patterns are released by damaged cells and trigger neuroinflammation through activation of non-specific pattern recognition receptors, e.g., toll-like receptors (TLRs. Since the role of TLR2 and 4 after traumatic brain injury (TBI is still unclear, we examined the outcome and the expression of pro-inflammatory mediators after experimental TBI in Tlr2/4−/− and wild-type (WT mice. Tlr2/4−/− and WT mice were subjected to controlled cortical injury and contusion volume and brain edema formation were assessed 24 h thereafter. Expression of inflammatory markers in brain tissue was measured by quantitative PCR 15 min, 3 h, 6 h, 12 h, and 24 h after controlled cortical impact (CCI. Contusion volume was significantly attenuated in Tlr2/4−/− mice (29.7 ± 0.7 mm3 as compared to 33.5 ± 0.8 mm3 in WT; p < 0.05 after CCI while brain edema was not affected. Only interleukin (IL-1β gene expression was increased after CCI in the Tlr2/4−/− relative to WT mice. Inducible nitric oxide synthetase, TNF, IL-6, and COX-2 were similar in injured WT and Tlr2/4−/− mice, while the increase in high-mobility group box 1 was attenuated at 6 h. TLR2 and 4 are consequently shown to potentially promote secondary brain injury after experimental CCI via neuroinflammation and may therefore represent a novel therapeutic target for the treatment of TBI.

Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

Science.gov (United States)

Seifert, Lena; Deutsch, Michael; Alothman, Sara; Alqunaibit, Dalia; Werba, Gregor; Pansari, Mridul; Pergamo, Matthew; Ochi, Atsuo; Torres-Hernandez, Alejandro; Levie, Elliot; Tippens, Daniel; Greco, Stephanie H; Tiwari, Shaun; Ly, Nancy Ngoc Giao; Eisenthal, Andrew; van Heerden, Eliza; Avanzi, Antonina; Barilla, Rocky; Zambirinis, Constantinos P; Rendon, Mauricio; Daley, Donnele; Pachter, H Leon; Hajdu, Cristina; Miller, George

2015-12-01

Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1(-/-) mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS)-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF) expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Enhanced Dendritic Cell-Mediated Antigen-Specific CD4+ T Cell Responses: IFN-Gamma Aids TLR Stimulation

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Kuo-Ching Sheng

2013-01-01

Full Text Available Phenotypic maturation and T cell stimulation are two functional attributes of DCs critical for immune induction. The combination of antigens, including those from cancer, with Toll-like receptor (TLR ligands induces far superior cellular immune responses compared to antigen alone. In this study, IFN-gamma treatment of bone marrow-derived DC, followed by incubation with the TLR2, TLR4, or TLR9 agonists, enhanced DC activation compared to TLR ligation alone. Most notably, the upregulation of CD40 with LPS stimulation and CD86 with CpG stimulation was observed in in vitro cultures. Similarly, IFN-gamma coinjected with TLR ligands was able to promote DC activation in vivo, with DCs migrating from the site of immunization to the popliteal lymph nodes demonstrating increased expression of CD80 and CD86. The heightened DC activation translated to a drastic increase in T cell stimulatory capacity in both antigen independent and antigen dependent fashions. This is the first time that IFN-gamma has been shown to have a combined effect with TLR ligation to enhance DC activation and function. The results demonstrate the novel use of IFN-gamma together with TLR agonists to enhance antigen-specific T cell responses, for applications in the development of enhanced vaccines and drug targets against diseases including cancer.

Neonatal plasma polarizes TLR4-mediated cytokine responses towards low IL-12p70 and high IL-10 production via distinct factors.

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Mirjam E Belderbos

Full Text Available Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP or soluble CD14 (sCD14. The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection.

Neonatal Plasma Polarizes TLR4-Mediated Cytokine Responses towards Low IL-12p70 and High IL-10 Production via Distinct Factors

Science.gov (United States)

Belderbos, Mirjam E.; Levy, Ofer; Stalpers, Femke; Kimpen, Jan L.; Meyaard, Linde; Bont, Louis

2012-01-01

Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR) responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs) produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP) or soluble CD14 (sCD14). The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection. PMID:22442690

Structure-based discovery of an immunomodulatory inhibitor of TLR1-TLR2 heterodimerization from a natural product-like database.

Science.gov (United States)

Zhong, Zhangfeng; Liu, Li-Juan; Dong, Zhi-Qiang; Lu, Lihua; Wang, Modi; Leung, Chung-Hang; Ma, Dik-Lung; Wang, Yitao

2015-06-30

We report herein the identification of an immunomodulatory natural product-like compound as a direct inhibitor of TLR1-TLR2 heterodimerization. Compound suppressed TNF-α and IL-6 secretion in Pam3CSK4-induced macrophages. Moreover, compound inhibited the phagocytic activity of macrophages, presumably through modulation of TLR1-TLR2 signaling and inactivation of NF-κB. Molecular docking revealed that compound bound to the interface region of TLR1-TLR2 by forming two hydrogen bonds with residues lining the binding site. To our knowledge, compound has been only the second inhibitor overall of TLR1-TLR2 heterodimerization reported to date.

Pharmacological Evaluation of Antidepressant-Like Effect of Genistein and Its Combination with Amitriptyline: An Acute and Chronic Study

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Gaurav Gupta

2015-01-01

Full Text Available The present study was designed to evaluate the acute and chronic antidepressant effect of genistein in combination with amitriptyline in mice. Animals were divided into six groups (n=6 for treatment with water, genistein, or amitriptyline, either alone or in combination for ten days. Animals were subjected to locomotor activity testing; tail suspension test (TST; and forced swim test (FST and immobility time was recorded on day one and day ten. Acute treatment of all treatment groups did not significantly reduce the immobility time (p>0.05. Chronic treatment of combination of genistein (10 mg/kg and amitriptyline (5 mg/kg and 10 mg/kg significantly reduced the immobility time as compared to control group (p<0.001 and was comparable to amitriptyline alone (10 mg/kg. However, no changes in anti-immobility activity in combination of subeffective doses of genistein (5 mg/kg and amitriptyline (5 mg/kg were observed. Genistein at its standard dose (10 mg/kg rendered synergistic effects in combination with subeffective dose of amitriptyline (5 mg/kg and additive effects in combination with therapeutic dose of amitriptyline (10 mg/kg.

Expression and significance of HMGB1, TLR4 and NF-κB p65 in human epidermal tumors

International Nuclear Information System (INIS)

Weng, Hui; Deng, Yunhua; Xie, Yuyan; Liu, Hongbo; Gong, Feili

2013-01-01

High mobility group protein box 1 (HMGB1) is a DNA binding protein located in nucleus. It is released into extracellular fluid where it acts as a novel proinflammatory cytokine which interacts with Toll like receptor 4 (TLR4) to activate nuclear factor-κB (NF-κB). This sequence of events is involved in tumor growth and progression. However, the effects of HMGB1, TLR4 and NF-κB on epidermal tumors remain unclear. Human epidermal tumor specimens were obtained from 96 patients. Immunohistochemistry was used to detect expression of HMGB1, TLR4 and NF-κB p65 in human epidermal tumor and normal skin specimens. Western blot analysis was used to detect the expression of NF-κB p65 in epithelial cell nuclei in human epidermal tumor and normal tissues. Immunohistochemistry and western blot analysis indicated a progressive but statistically significant increase in p65 expression in epithelial nuclei in benign seborrheic keratosis (SK), precancerous lesions (PCL), low malignancy basal cell carcinoma (BCC) and high malignancy squamous cell carcinoma (SCC) (P <0.01). The level of extracellular HMGB1 in SK was significantly higher than in normal skin (NS) (P <0.01), and was higher than in SCC but without statistical significance. The level of TLR4 on epithelial membranes of SCC cells was significantly higher than in SK, PCL, BCC and NS (P <0.01). There was a significant positive correlation between p65 expression in the epithelial nuclei and TLR4 expression on the epithelial cell membranes (r = 0.3212, P <0.01). These findings indicate that inflammation is intensified in parallel with increasing malignancy. They also indicate that the TLR4 signaling pathway, rather than HMGB1, may be the principal mediator of inflammation in high-grade malignant epidermal tumors. Combined detection of p65 in the epithelial nuclei and TLR4 on the epithelial membranes may assist the accurate diagnosis of malignant epidermal tumors

TLR4 response mediates ethanol-induced neurodevelopment alterations in a model of fetal alcohol spectrum disorders.

Science.gov (United States)

Pascual, María; Montesinos, Jorge; Montagud-Romero, Sandra; Forteza, Jerónimo; Rodríguez-Arias, Marta; Miñarro, José; Guerri, Consuelo

2017-07-24

Inflammation during brain development participates in the pathogenesis of early brain injury and cognitive dysfunctions. Prenatal ethanol exposure affects the developing brain and causes neural impairment, cognitive and behavioral effects, collectively known as fetal alcohol spectrum disorders (FASD). Our previous studies demonstrate that ethanol activates the innate immune response and TLR4 receptor and causes neuroinflammation, brain damage, and cognitive defects in the developmental brain stage of adolescents. We hypothesize that by activating the TLR4 response, maternal alcohol consumption during pregnancy triggers the release of cytokines and chemokines in both the maternal sera and brains of fetuses/offspring, which impairs brain ontogeny and causes cognitive dysfunction. WT and TLR4-KO female mice treated with or without 10% ethanol in the drinking water during gestation and lactation were used. Cytokine/chemokine levels were determined by ELISA in the amniotic fluid, maternal serum, and cerebral cortex, as well as in the offspring cerebral cortex. Microglial and neuronal markers (evaluated by western blotting), myelin proteins (immunohistochemical and western blotting) and synaptic parameters (western blotting and electron microscopy) were assessed in the cortices of the WT and TLR4-KO pups on PND 0, 20, and 66. Behavioral tests (elevated plus maze and passive avoidance) were performed in the WT and TLR4-KO mice on PND 66 exposed or not to ethanol. We show that alcohol intake during gestation and lactation increases the levels of several cytokines/chemokines (IL-1β, IL-17, MIP-1α, and fractalkine) in the maternal sera, amniotic fluid, and brains of fetuses and offspring. The upregulation of cytokines/chemokines is associated with an increase in activated microglia markers (CD11b and MHC-II), and with a reduction in some synaptic (synaptotagmin, synapsin IIa) and myelin (MBP, PLP) proteins in the brains of offspring on days 0, 20, and 66 (long-term effects

Boxb mediate BALB/c mice corneal inflammation through a TLR4/MyD88-dependent signaling pathway in Aspergillus fumigatus keratitis

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Min Liu

2018-04-01

Full Text Available AIM: To investigate whether high-mobility group box 1 (HMGB1 Boxb exacerbates BALB/c mice corneal immune responses and inflammatory through the Toll-like receptor 4 (TLR4/myeloid differentiation primary response 88 (MyD88-dependent signaling pathway in Aspergillus fumigatus (A. fumigatus keratitis. METHODS: The mice corneas were pretreated with phosphate buffer saline (PBS, Boxb before A. fumigatus infection. The abdominal cavity extracted macrophages were pretreated with PBS, Boxb, TLR4 inhibitor (CLI-095, Dimethyl sulfoxide (DMSO separately before A. fumigatus hyphae stimulation. HMGB1 was detected in normal and infected mice corneas and macrophages by real-time reverse transcriptase polymerase chain reaction (RT-PCR, the TLR4, MyD88, interleukin-1β (IL-1β, tumor necrosis factor-α (TNF-α were detected by Western blot and PCR. RESULTS: In BALB/c mice corneas, the expressions of TLR4, HMGB1, IL-1β, TNF-α were increased after A. fumigatus infection. While pretreatment with Boxb significantly increased the expressions of TLR4, HMGB1, MyD88, IL-1β, TNF-α compared with PBS control after infection. In BALB/c mice abdominal cavity extracted macrophages, pretreatment with Boxb increased the expressions of TLR4, HMGB1, MyD88, IL-1β, TNF-α, while pretreatment with CLI-095 and Boxb significantly decreased the expressions of TLR4, HMGB1, MyD88, IL-1β, TNF-α. CONCLUSION: In A. fumigatus keratitis, Boxb play a pro-inflammatory role in corneal anti-fungi immune response through the HMGB1-TLR4-MyD88 signal pathway.

Intradermally administered TLR4 agonist GLA-SE enhances the capacity of human skin DCs to activate T cells and promotes emigration of Langerhans cells

NARCIS (Netherlands)

Schneider, Laura P.; Schoonderwoerd, Antoinet J.; Moutaftsi, Magdalini; Howard, Randall F.; Reed, Steven G.; de Jong, Esther C.; Teunissen, Marcel B. M.

2012-01-01

The natural TLR4 agonist lipopolysaccharide (LPS) has notable adjuvant activity. However, it is not useful as a vaccine adjuvant due to its toxicity. Glucopyranosyl lipid A (GLA) is a synthetic derivative of the lipid A tail of LPS with limited cytotoxicity, but strong potential to induce immune

Curcumin attenuates acute inflammatory injury by inhibiting the TLR4/MyD88/NF-κB signaling pathway in experimental traumatic brain injury

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2014-01-01

Background Traumatic brain injury (TBI) initiates a neuroinflammatory cascade that contributes to substantial neuronal damage and behavioral impairment, and Toll-like receptor 4 (TLR4) is an important mediator of thiscascade. In the current study, we tested the hypothesis that curcumin, a phytochemical compound with potent anti-inflammatory properties that is extracted from the rhizome Curcuma longa, alleviates acute inflammatory injury mediated by TLR4 following TBI. Methods Neurological function, brain water content and cytokine levels were tested in TLR4-/- mice subjected to weight-drop contusion injury. Wild-type (WT) mice were injected intraperitoneally with different concentrations of curcumin or vehicle 15 minutes after TBI. At 24 hours post-injury, the activation of microglia/macrophages and TLR4 was detected by immunohistochemistry; neuronal apoptosis was measured by FJB and TUNEL staining; cytokines were assayed by ELISA; and TLR4, MyD88 and NF-κB levels were measured by Western blotting. In vitro, a co-culture system comprised of microglia and neurons was treated with curcumin following lipopolysaccharide (LPS) stimulation. TLR4 expression and morphological activation in microglia and morphological damage to neurons were detected by immunohistochemistry 24 hours post-stimulation. Results The protein expression of TLR4 in pericontusional tissue reached a maximum at 24 hours post-TBI. Compared with WT mice, TLR4-/- mice showed attenuated functional impairment, brain edema and cytokine release post-TBI. In addition to improvement in the above aspects, 100 mg/kg curcumin treatment post-TBI significantly reduced the number of TLR4-positive microglia/macrophages as well as inflammatory mediator release and neuronal apoptosis in WT mice. Furthermore, Western blot analysis indicated that the levels of TLR4 and its known downstream effectors (MyD88, and NF-κB) were also decreased after curcumin treatment. Similar outcomes were observed in the microglia and

Lipopolysaccharide-induced inhibition of transcription of tlr4 in vitro is reversed by dexamethasone and correlates with presence of conserved NFκB binding sites

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Bonin, Camila P., E-mail: mila_bonin@yahoo.com.br [Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-900 (Brazil); Baccarin, Raquel Y.A., E-mail: baccarin@usp.br [Department of Clinics, School of Veterinary Medicine, University of São Paulo, São Paulo 05508-900 (Brazil); Nostell, Katarina, E-mail: katarina.nostell@slu.se [Department of Clinical Sciences, Swedish University of Agricultural Sciences, Box 7054, 750 07 Uppsala (Sweden); Nahum, Laila A., E-mail: laila@nahum.com.br [Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte 30190-002 (Brazil); Faculdade Infórium de Tecnologia, Belo Horizonte 30130-180 (Brazil); Fossum, Caroline, E-mail: caroline.fossum@bvf.slu.se [Department of Biomedicine and Veterinary Public Health, Section for Immunology, Swedish University of Agricultural Sciences, BMC, Box 588, SE 751 23 Uppsala (Sweden); Camargo, Maristela M. de, E-mail: mmcamar@usp.br [Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-900 (Brazil)

2013-03-08

Highlights: ► Chimpanzees, horses and humans have regions of similarity on TLR4 and MD2 promoters. ► Rodents have few regions of similarity on TLR4 promoter when compared to primates. ► Conserved NFkB binding sites were found in the promoters of TLR4 and MD2. ► LPS-induced inhibition of TLR4 transcription is reversed by dexamethasone. ► LPS-induced transcription of MD2 is inhibited by dexamethasone. -- Abstract: Engagement of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) is a master trigger of the deleterious effects of septic shock. Horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. Analysis of tlr4 promoters revealed high similarity among LPS-sensitive species (human, chimpanzee, and horse) and low similarity with LPS-resistant species (mouse and rat). Four conserved nuclear factor kappa B (NFκB) binding sites were found in the tlr4 promoter and two in the md2 promoter sequences that are likely to be targets for dexamethasone regulation. In vitro treatment of equine peripheral blood mononuclear cells (eqPBMC) with LPS decreased transcripts of tlr4 and increased transcription of md2 (myeloid differentiation factor 2) and cd14 (cluster of differentiation 14). Treatment with dexamethasone rescued transcription of tlr4 after LPS inhibition. LPS-induced transcription of md2 was inhibited in the presence of dexamethasone. Dexamethasone alone did not affect transcription of tlr4 and md2.

Tissue Factor and Toll Like Receptor (TLR)4 in Hyperglycemia-Hyperinsulinemia: Effects in Healthy Subjects, and Type 1 and Type 2 Diabetes Mellitus

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Singh, Anamika; Boden, Guenther; Rao, A. Koneti

2015-01-01

SUMMARY Background Diabetes mellitus (DM) patients have increased cardiovascular events. Blood tissue factor-procoagulant activity (TF-PCA), the initiating mechanism for blood coagulation, is elevated in DM. We have shown that hyperglycemia (HG), hyperinsulinemia (HI) and combined HG+HI (induced using 24 hr infusion clamps) increases TF-PCA in healthy and T2DM subjects, but not in T1DM subjects. The mechanisms for this are unknown. DM patients have elevated plasma lipopolysaccharide (LPS), a toll-like receptor (TLR) 4 ligand. We postulated that TLR4 plays a role in modulating TF levels. Objectives and Methods We studied the effect of HG+HI on TLR4 and TF-PCA in vivo during 24 hr HG+HI infusion clamps in healthy subjects, and T1DM and T2DM subjects, and in vitro in blood. Results In vivo, in healthy subjects, 24 hr HG + HI infusion increased TLR4 6-fold, which correlated with TF-PCA (r= 0.91, p<0.0001). T2DM patients showed smaller increases in both. In T1DM subjects, TLR4 declined (50%, p<0.05) and correlated with TF-PCA (r=0.55; p<0.05). In vitro, HG (200 mg/dl added glucose) and HI (1-100 nM added insulin) increased TF-PCA in healthy subjects (~2-fold, 2-4 hr). Insulin inhibited by ~30% LPS-induced increase in TF-PCA and high glucose reversed it. TLR4 levels paralleled TF-PCA (r=0.71, p<0.0001); HG and HI increased TLR4 and insulin inhibited LPS-induced TLR4 increase. Conclusions This is first evidence that even in healthy subjects, HG of short duration increases TLR4 and TF-PCA, key players in inflammation and thrombosis. TLR4-TF interplay is strikingly different in non-diabetic, T1DM and T2DM subjects. PMID:25653143

Effects of administration of sertraline, clozapine, amitriptyline and ...

African Journals Online (AJOL)

Dr Gatsing

imipramine on brain serotonin, liver enzymes and blood chemistry of rabbit. O. A. T. EBUEHI ... The chronic administration of sertraline, clozapine, amitriptyline and imipramine on brain serotonin, liver ..... and Alcohol consumption affect human.

Altered gut microbiome in a mouse model of Gulf War Illness causes neuroinflammation and intestinal injury via leaky gut and TLR4 activation.

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Firas Alhasson

Full Text Available Many of the symptoms of Gulf War Illness (GWI that include neurological abnormalities, neuroinflammation, chronic fatigue and gastrointestinal disturbances have been traced to Gulf War chemical exposure. Though the association and subsequent evidences are strong, the mechanisms that connect exposure to intestinal and neurological abnormalities remain unclear. Using an established rodent model of Gulf War Illness, we show that chemical exposure caused significant dysbiosis in the gut that included increased abundance of phylum Firmicutes and Tenericutes, and decreased abundance of Bacteroidetes. Several gram negative bacterial genera were enriched in the GWI-model that included Allobaculum sp. Altered microbiome caused significant decrease in tight junction protein Occludin with a concomitant increase in Claudin-2, a signature of a leaky gut. Resultant leaching of gut caused portal endotoxemia that led to upregulation of toll like receptor 4 (TLR4 activation in the small intestine and the brain. TLR4 knock out mice and mice that had gut decontamination showed significant decrease in tyrosine nitration and inflammatory mediators IL1β and MCP-1 in both the small intestine and frontal cortex. These events signified that gut dysbiosis with simultaneous leaky gut and systemic endotoxemia-induced TLR4 activation contributes to GW chemical-induced neuroinflammation and gastrointestinal disturbances.

Clinical characteristics and frequency of TLR4 polymorphisms in Brazilian patients with ankylosing spondylitis

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Natalia Pereira Machado

Full Text Available ABSTRACT Objectives: Innate immunity is involved in the physiopathology of ankylosing spondylitis (AS, with the participation of Gram-negative bacteria, modulation of human leukocyte antigen (HLA B27 and the involvement of pattern recognition receptors, such as Toll-like receptors (TLRs. The aim of this study was to investigate the clinical characteristics and frequency of TLR4 polymorphisms (Asp299Gly and Thr 399Ile in a cohort of Brazilian patients with AS. Methods: A cross-sectional study was carried out involving 200 patients with a diagnosis of AS and a healthy control group of 200 individuals. Disease activity, severity and functional capacity were measured. The study of TLR4 polymorphisms was performed using the restriction fragment length polymorphism method. HLA-B27 was analyzed by conventional polymerase chain reaction. The IBM SPSS Statistics 20 program was used for the statistical analysis, with p-values less than 0.05 considered significant. Results: Mean age and disease duration were 43.1 ± 12.7 and 16.6 ± 9.2 years, respectively. The sample was predominantly male (71% and non-Caucasian (52%. A total of 66% of the group of patients were positive for HLA-B27. The sample of patients was characterized by moderate functional impairment and a high degree of disease activity. No significant association was found between the two TLR4 polymorphisms and susceptibility to AS. Conclusions: TLR4 polymorphisms 399 and 299 were not more frequent in patients with AS in comparison to the health controls and none of the clinical variables were associated with these polymorphisms.

Molecular and functional characterization of Toll-like receptor (Tlr)1 and Tlr2 in common carp (Cyprinus carpio).

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Fink, Inge R; Pietretti, Danilo; Voogdt, Carlos G P; Westphal, Adrie H; Savelkoul, Huub F J; Forlenza, Maria; Wiegertjes, Geert F

2016-09-01

Toll-like receptors (TLRs) are fundamental components of innate immunity that play significant roles in the defence against pathogen invasion. In this study, we present the molecular characterization of the full-length coding sequence of tlr1, tlr2a and tlr2b from common carp (Cyprinus carpio). Each is encoded within a single exon and contains a conserved number of leucine-rich repeats, a transmembrane region and an intracellular TIR domain for signalling. Indeed, sequence, phylogenetic and synteny analysis of carp tlr1, tlr2a and tlr2b support that these genes are orthologues of mammalian TLR1 and TLR2. The tlr genes are expressed in various immune organs and cell types. Furthermore, the carp sequences exhibited a good three-dimensional fit with the heterodimer structure of human TLR1-TLR2, including the potential to bind to the ligand Pam3CSK4. This supports the possible formation of carp Tlr1-Tlr2 heterodimers. However, we were unable to demonstrate Tlr1/Tlr2-mediated ligand binding in transfected cell lines through NF-κB activation, despite showing the expression and co-localization of Tlr1 and Tlr2. We discuss possible limitations when studying ligand-specific activation of NF-κB after expression of Tlr1 and/or Tlr2 in human but also fish cell lines and we propose alternative future strategies for studying ligand-binding properties of fish Tlrs. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Association Between Antibiotic Exposure, Bronchiolitis, and TLR4 (rs1927911) Polymorphisms in Childhood Asthma

Science.gov (United States)

Lee, Eun; Kwon, Ji-Won; Kim, Hyo-Bin; Yu, Ho-Sung; Kang, Mi-Jin; Hong, Kyungmo; Yang, Song I; Jung, Young Ho; Lee, Seung-Hwa; Choi, Kil Young; Shin, Hye Lim; Hong, Seo Ah; Kim, Hyung Young; Seo, Ju-Hee; Kim, Byoung-Ju; Lee, So Yeon; Song, Dae Jin; Kim, Woo-Kyung; Jang, Gwang Cheon; Shim, Jung Yeon

2015-01-01

Purpose The complex interplay between environmental and genetic factors plays an important role in the development of asthma. Several studies have yielded conflicting results regarding the 2 asthma-related risk factors: antibiotic usage during infancy and/or a history of bronchiolitis during early life and the development of asthma. In addition to these risk factors, we also explored the effects of Toll-like receptor 4 (TLR4) polymorphism on the development of childhood asthma. Methods This cross-sectional study involved 7,389 middle school students who were from 8 areas of Seoul, Korea, and completed the International Study of Asthma and Allergies in Childhood questionnaire. The TLR4 polymorphism rs1927911 was genotyped in 1,395 middle school students from two areas using the TaqMan assay. Results Bronchiolitis in the first 2 years of life, antibiotic exposure during the first year of life, and parental history of asthma were independent risk factors for the development of asthma. When combined, antibiotic use and a history of bronchiolitis increased the risk of asthma (adjusted odds ratio [aOR]: 4.64, 95% confidence interval [CI]: 3.09-6.97, P value for interaction=0.02). In subjects with CC genotype of TLR4, antibiotic exposure and a history of bronchiolitis during infancy, the risk of asthma was increased, compared to subjects without these risk factors (aOR: 5.72, 95% CI: 1.74-18.87). Conclusions Early-life antibiotic exposures and a history of bronchiolitis are risk factors for asthma in young adolescents. Polymorphisms of TLR4 modified the influence of these environmental factors. Reducing antibiotic exposure and preventing bronchiolitis during infancy may prevent the development of asthma, especially in genetically susceptible subjects. PMID:25729624

Radioimmunoassay for nortriptyline and amitriptyline

International Nuclear Information System (INIS)

Turner, P.

1977-01-01

A description has been given (Aherne, G.W.; Marks, V.; Mould, G.; Stout, G.; Lancet; 1214, June 4 (1977)) of a radioimmunoassay (RIA) technique having advantages for monitoring patient response by estimation of plasma concentrations of nortriptyline and amitriptyline. A wide range of monoamine-reuptake-inhibiting drugs is now used in the treatment of depressive illness. There are other analytical techniques such as gas-liquid chromatography which can be used in the estimation of most of these drugs and their major metabolites, as well as for the identification of some other centrally-acting drugs such as benzodiazepines. The chromatographic technique was able to detect the administration of the wrong drug in one comparative study of two antidepressive drugs. Chromatographic and RIA methods therefore both have their own analytical roles according to the clinical or research problem being investigated. (U.K.)

TLR5 signaling enhances the proliferation of human allogeneic CD40-activated B cell induced CD4hiCD25+ regulatory T cells.

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Ping-Lung Chan

Full Text Available Although diverse functions of different toll-like receptors (TLR on human natural regulatory T cells have been demonstrated recently, the role of TLR-related signals on human induced regulatory T cells remain elusive. Previously our group developed an ex vivo high-efficient system in generating human alloantigen-specific CD4(hiCD25(+ regulatory T cells from naïve CD4(+CD25(- T cells using allogeneic CD40-activated B cells as stimulators. In this study, we investigated the role of TLR5-related signals on the generation and function of these novel CD4(hiCD25(+ regulatory T cells. It was found that induced CD4(hiCD25(+ regulatory T cells expressed an up-regulated level of TLR5 compared to their precursors. The blockade of TLR5 using anti-TLR5 antibodies during the co-culture decreased CD4(hiCD25(+ regulatory T cells proliferation by induction of S phase arrest. The S phase arrest was associated with reduced ERK1/2 phosphorylation. However, TLR5 blockade did not decrease the CTLA-4, GITR and FOXP3 expressions, and the suppressive function of CD4(hiCD25(+ regulatory T cells. In conclusion, we discovered a novel function of TLR5-related signaling in enhancing the proliferation of CD4(hiCD25(+ regulatory T cells by promoting S phase progress but not involved in the suppressive function of human CD40-activated B cell-induced CD4(hiCD25(+ regulatory T cells, suggesting a novel role of TLR5-related signals in the generation of induced regulatory T cells.

Splenectomy following MCAO inhibits the TLR4-NF-κB signaling pathway and protects the brain from neurodegeneration in rats.

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Belinga, Victor Fabrice; Wu, Guan-Jin; Yan, Fu-Ling; Limbenga, Erica Audrey

2016-04-15

The Toll-like receptor 4(TLR4)/nuclear factor kappa B NF-κB inflammatory pathway contributes to secondary inflammation in many diseases including stroke. Moreover, the neuroprotective effect of splenectomy in stroke is supported by a vast body of experimental evidence. Nevertheless, the underlying mechanism(s) by which splenectomy enhance neuroprotection in stroke is still poorly understood. Our study aimed to investigate whether post-ischemic splenectomy modulate the TLR4/NF-κB inflammatory pathway in stroke. Immunohistochemistry was used to evaluate the levels of TLR4 and NF-κB expression in brain areas (parietal lobe, hippocampus and striatum) of rats that underwent: MCAO-splenectomy surgery (MS ); MCAO surgery without splenectomy (MCAO control or MC); Sham MCAO and splenectomy surgery (sham control group or SC group respectively. Apoptosis in these areas was assessed by TUNEL detection technique. The levels of TLR4 and NF-κB expression were significantly reduced in splenectomized rats relative to the MS group (Psplenectomy in ischemic stroke. Our results suggest that such an effect might be due to the inhibition of theTLR4/NF-κB inflammatory pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

Toxicokinetics of nortriptyline and amitriptyline: two case reports

NARCIS (Netherlands)

Franssen, E. J. F.; Kunst, P. W. A.; Bet, P. M.; Strack van Schijndel, R. J. M.; van Loenen, A. C.; Wilhelm, A. J.

2003-01-01

Two cases are presented of intentional intoxications with the tricyclic antidepressants (TCAs) nortriptyline (NT) and amitriptyline (AT). The peak plasma concentrations were 2290 microg/L and 2900 microg/L, respectively. The active metabolites E-10-hydroxynortriptyline (EHNT) and

Nonbilayer Phospholipid Arrangements Are Toll-Like Receptor-2/6 and TLR-4 Agonists and Trigger Inflammation in a Mouse Model Resembling Human Lupus

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Carlos Wong-Baeza

2015-01-01

Full Text Available Systemic lupus erythematosus is characterized by dysregulated activation of T and B cells and autoantibodies to nuclear antigens and, in some cases, lipid antigens. Liposomes with nonbilayer phospholipid arrangements induce a disease resembling human lupus in mice, including IgM and IgG antibodies against nonbilayer phospholipid arrangements. As the effect of these liposomes on the innate immune response is unknown and innate immune system activation is necessary for efficient antibody formation, we evaluated the effect of these liposomes on Toll-like receptor (TLR signaling, cytokine production, proinflammatory gene expression, and T, NKT, dendritic, and B cells. Liposomes induce TLR-4- and, to a lesser extent, TLR-2/TLR-6-dependent signaling in TLR-expressing human embryonic kidney (HEK cells and bone marrow-derived macrophages. Mice with the lupus-like disease had increased serum concentrations of proinflammatory cytokines, C3a and C5a; they also had more TLR-4-expressing splenocytes, a higher expression of genes associated with TRIF-dependent TLR-4-signaling and complement activation, and a lower expression of apoptosis-related genes, compared to healthy mice. The percentage of NKT and the percentage and activation of dendritic and B2 cells were also increased. Thus, TLR-4 and TLR-2/TLR-6 activation by nonbilayer phospholipid arrangements triggers an inflammatory response that could contribute to autoantibody production and the generation of a lupus-like disease in mice.

Antitumor Activity of Portulaca Oleracea L. Polysaccharide on HeLa Cells Through Inducing TLR4/NF-κB Signaling.

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Zhao, Rui; Zhang, Tao; Ma, Baoling; Li, Xing

2017-01-01

Abstarct We have previously shown that Portulaca oleracea L. polysaccharide (POL-P3b) possesses the ability to inhibit cervical cancer cell growth in vitro and in vivo. In this study, we explored how toll-like receptor 4 (TLR4) signaling correlated with the antitumor mechanism of POL-P3b. Western blotting was utilized to detect the expression of TLR4 and the downstream signaling pathway. The level of inflammatory mediator was quantified using enzyme-linked immunosorbent assay (ELISA) kits. The effects of POL-P3b on the proliferation and apoptosis in HeLa cells were determined by WST-8 assay and Hoechst 33342/propidium iodide (PI) assay. Our results demonstrated that lipopolysaccharide (LPS) binding to TLR4 on tumor cells could enhance HeLa cell proliferation and increase the expression of TLR4 and the downstream molecules. Treating HeLa cells with POL-P3b could decrease the proliferation of HeLa cells, and upregulate Bax level and downregulate Bcl-2 level in a concentration-dependent manner. In addition, POL-P3b inhibited the protein expression levels of TLR4, MyD88, TRAF6, Activator Protein-1 (AP-1) and nuclear factor-κB (NF-κB) subunit P65 in HeLa cells. Furthermore, POL-P3b also reduced the production of cytokine/chemokine. Taken together, the present work suggested the antitumor mechanism of POL-P3b by downregulating TLR4 downstream signaling pathway and inducing cell apoptosis. Our results may provide direct evidence to suggest that POL-P3b should be considered as a potent nutrient supplement for oncotherapy.

Matrine pretreatment improves cardiac function in rats with diabetic cardiomyopathy via suppressing ROS/TLR-4 signaling pathway.

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Liu, Zhong-wei; Wang, Jun-kui; Qiu, Chuan; Guan, Gong-chang; Liu, Xin-hong; Li, Shang-jian; Deng, Zheng-rong

2015-03-01

Matrine is an alkaloid from Sophora alopecuroides L, which has shown a variety of pharmacological activities and potential therapeutic value in cardiovascular diseases. In this study we examined the protective effects of matrine against diabetic cardiomyopathy (DCM) in rats. Male SD rats were injected with streptozotocin (STZ) to induce DCM. One group of DCM rats was pretreated with matrine (200 mg·kg(-1)·d(-1), po) for 10 consecutive days before STZ injection. Left ventricular function was evaluated using invasive hemodynamic examination, and myocardiac apoptosis was assessed. Primary rat myocytes were used for in vitro experiments. Intracellular ROS generation, MDA content and GPx activity were determined. Real-time PCR and Western blotting were performed to detect the expression of relevant mRNAs and proteins. DCM rats exhibited abnormally elevated non-fasting blood glucose levels at 4 weeks after STZ injection, and LV function impairment at 16 weeks. The cardiac tissues of DCM rats showed markedly increased apoptosis, excessive ROS production, and activation of TLR-4/MyD-88/caspase-8/caspase-3 signaling. Pretreatment with matrine significantly decreased non-fasting blood glucose levels and improved LV function in DCM rats, which were associated with reducing apoptosis and ROS production, and suppressing TLR-4/MyD-88/caspase-8/caspase-3 signaling in cardiac tissues. Incubation in a high-glucose medium induced oxidative stress and activation of TLR-4/MyD-88 signaling in cultured myocytes in vitro, which were significantly attenuated by pretreatment with N-acetylcysteine. Excessive ROS production in DCM activates the TLR-4/MyD-88 signaling, resulting in cardiomyocyte apoptosis, whereas pretreatment with matrine improves cardiac function via suppressing ROS/TLR-4 signaling pathway.

Sublingual flagellin protects against acute pneumococcal pneumonia in a TLR5-dependent and NLRC4-independent fashion.

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Muñoz-Wolf, Natalia; Rial, Analía; Fougeron, Delphine; Tabareau, Julien; Sirard, Jean-Claude; Chabalgoity, José A

2016-09-01

To evaluate efficacy of sublingual flagellin to treat acute pneumonia. Mice were treated sublingually with flagellin and challenged intranasally with a lethal dose of pneumococcus. Flagellins lacking TLR5 or NLRC4 activation domains were used to assess their contribution to protection. Sublingual flagellin protected mice in a TLR5-dependent, NLRC4-independent fashion. Neutrophils were required for protection. Flagellin-stimulated lung epithelial cells recapitulated the lung's transcriptional profile suggesting they could be targeted by flagellin in vivo. Ligation of TLR5, a pathogen recognition receptor not naturally engaged by pneumococcus, protects mice from invasive pneumonia when administered via sublingual route. This can be a highly cost-effective alternative therapy against pneumonia.

Neuroanatomical characterization of the cellular and axonal architecture of subcortical band heterotopia in the BXD29-Tlr4lps-2J/J mouse cortex.

Science.gov (United States)

Ramos, Raddy L; Toia, Alyssa R; Pasternack, Daniel M; Dotzler, Timothy P; Cuoco, Joshua A; Esposito, Anthony W; Le, Megan M; Parker, Alexander K; Goodman, Jeffrey H; Sarkisian, Matthew R

2016-11-19

Subcortical band heterotopia (SBH) are malformations of the human cerebral cortex typically associated with epilepsy and cognitive delay/disability. Rodent models of SBH have demonstrated strong face validity as they are accompanied by both cognitive deficits and spontaneous seizures or reduced seizure threshold. BXD29-Tlr4 lps-2J /J recombinant inbred mice display striking bilateral SBH, partial callosal agenesis, morphological changes in subcortical structures of the auditory pathway, and display sensory deficits in behavioral tests (Rosen et al., 2013; Truong et al., 2013, 2015). Surprisingly, these mice show no cognitive deficits and have a higher seizure threshold to chemi-convulsive treatment (Gabel et al., 2013) making them different than other rodent SBH models described previously. In the present report, we perform a detailed characterization of the cellular and axonal constituents of SBH in BXD29-Tlr4 lps-2J /J mice and demonstrate that various types of interneurons and glia as well as cortical and subcortical projections are found in SBH. In addition, the length of neuronal cilia was reduced in SBH compared to neurons in the overlying and adjacent normotopic cortex. Finally, we describe additional and novel malformations of the hippocampus and neocortex present in BXD29-Tlr4 lps-2J /J mice. Together, our findings in BXD29-Tlr4 lps-2J /J mice are discussed in the context of the known neuroanatomy and phenotype of other SBH rodent models. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Modulation of endotoxicity of Shigella generalized modules for membrane antigens (GMMA) by genetic lipid A modifications: relative activation of TLR4 and TLR2 pathways in different mutants.

Science.gov (United States)

Rossi, Omar; Pesce, Isabella; Giannelli, Carlo; Aprea, Susanna; Caboni, Mariaelena; Citiulo, Francesco; Valentini, Sara; Ferlenghi, Ilaria; MacLennan, Calman Alexander; D'Oro, Ugo; Saul, Allan; Gerke, Christiane

2014-09-05

Outer membrane particles from Gram-negative bacteria are attractive vaccine candidates as they present surface antigens in their natural context. We previously developed a high yield production process for genetically derived particles, called generalized modules for membrane antigens (GMMA), from Shigella. As GMMA are derived from the outer membrane, they contain immunostimulatory components, especially lipopolysaccharide (LPS). We examined ways of reducing their reactogenicity by modifying lipid A, the endotoxic part of LPS, through deletion of late acyltransferase genes, msbB or htrB, in GMMA-producing Shigella sonnei and Shigella flexneri strains. GMMA with resulting penta-acylated lipid A from the msbB mutants showed a 600-fold reduced ability, and GMMA from the S. sonnei ΔhtrB mutant showed a 60,000-fold reduced ability compared with GMMA with wild-type lipid A to stimulate human Toll-like receptor 4 (TLR4) in a reporter cell line. In human peripheral blood mononuclear cells, GMMA with penta-acylated lipid A showed a marked reduction in induction of inflammatory cytokines (S. sonnei ΔhtrB, 800-fold; ΔmsbB mutants, 300-fold). We found that the residual activity of these GMMA is largely due to non-lipid A-related TLR2 activation. In contrast, in the S. flexneri ΔhtrB mutant, a compensatory lipid A palmitoleoylation resulted in GMMA with hexa-acylated lipid A with ∼10-fold higher activity to stimulate peripheral blood mononuclear cells than GMMA with penta-acylated lipid A, mostly due to retained TLR4 activity. Thus, for use as vaccines, GMMA will likely require lipid A penta-acylation. The results identify the relative contributions of TLR4 and TLR2 activation by GMMA, which need to be taken into consideration for GMMA vaccine development. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Inhibition of TLR2 signaling by small molecule inhibitors targeting a pocket within the TLR2 TIR domain

Science.gov (United States)

Mistry, Pragnesh; Laird, Michelle H. W.; Schwarz, Ryan S.; Greene, Shannon; Dyson, Tristan; Snyder, Greg A.; Xiao, Tsan Sam; Chauhan, Jay; Fletcher, Steven; Toshchakov, Vladimir Y.; MacKerell, Alexander D.; Vogel, Stefanie N.

2015-01-01

Toll-like receptor (TLR) signaling is initiated by dimerization of intracellular Toll/IL-1 receptor resistance (TIR) domains. For all TLRs except TLR3, recruitment of the adapter, myeloid differentiation primary response gene 88 (MyD88), to TLR TIR domains results in downstream signaling culminating in proinflammatory cytokine production. Therefore, blocking TLR TIR dimerization may ameliorate TLR2-mediated hyperinflammatory states. The BB loop within the TLR TIR domain is critical for mediating certain protein–protein interactions. Examination of the human TLR2 TIR domain crystal structure revealed a pocket adjacent to the highly conserved P681 and G682 BB loop residues. Using computer-aided drug design (CADD), we sought to identify a small molecule inhibitor(s) that would fit within this pocket and potentially disrupt TLR2 signaling. In silico screening identified 149 compounds and 20 US Food and Drug Administration-approved drugs based on their predicted ability to bind in the BB loop pocket. These compounds were screened in HEK293T-TLR2 transfectants for the ability to inhibit TLR2-mediated IL-8 mRNA. C16H15NO4 (C29) was identified as a potential TLR2 inhibitor. C29, and its derivative, ortho-vanillin (o-vanillin), inhibited TLR2/1 and TLR2/6 signaling induced by synthetic and bacterial TLR2 agonists in human HEK-TLR2 and THP-1 cells, but only TLR2/1 signaling in murine macrophages. C29 failed to inhibit signaling induced by other TLR agonists and TNF-α. Mutagenesis of BB loop pocket residues revealed an indispensable role for TLR2/1, but not TLR2/6, signaling, suggesting divergent roles. Mice treated with o-vanillin exhibited reduced TLR2-induced inflammation. Our data provide proof of principle that targeting the BB loop pocket is an effective approach for identification of TLR2 signaling inhibitors. PMID:25870276

[Effect of resveratrol on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment].

Science.gov (United States)

Lv, Jia-Shu; Jiang, Xue-Wei; Zhang, Yan; Zhen, Lei

2017-02-01

Through a study of the molecular mechanism of the effect of resveratrol(RSV) on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment, the therapeutic effect and molecular mechanism of resveratrol on periodontitis in patients with diabetes mellitus was investigated. Gingival epithelial cells were cultured in vitro; according to the way of action, the cultured cells were divided into control group, high glucose group(HG) and HG+RSV group. The mRNA expression of TLR4 was detected by PCR; The third generation of gingival epithelial cells were pre-treated with or without RSV for 24 h under high glucose conditions, and subsequently treated with LPS at 100 ng/mL for 2 h. ELISA was used to detect the secretion of IL-1 beta, IL-6, IL-8 and TNF- alpha; the activation of TLR4 downstream signaling molecules NF-κB p65, p38 MAPK, and STAT3 was determined by Western blot. SPSS17.0 software package was used for statistical analysis. RSV could reverse the increase of TLR4 level in gingival epithelial cells in high glucose medium.LPS markedly increased the expression and secretion of IL-1β, IL-6, IL-8, and TNF-α in GECs cultured in high glucose medium, which was partly blocked in the presence of RSV. Furthermore, Western blot results showed that RSV significantly suppressed the phosphorylation of TLR4 downstream factors NF-κB p65, p38MAPK, and STAT3. RSV reduces inflammatory cytokine secretion in gingival epithelial cells, through negative regulation of TLR4 signaling pathway.

Amitriptyline induces early growth response-1 gene expression via ERK and JNK mitogen-activated protein kinase pathways in rat C6 glial cells.

Science.gov (United States)

Chung, Eun Young; Shin, Soon Young; Lee, Young Han

2007-07-05

Astrocytes play important roles in guiding the construction of the nervous system, controlling extracellular ions and neurotransmitters, and regulating CNS synaptogenesis. Egr-1 is a transcription factor involved in neuronal differentiation and astrocyte cell proliferation. In this study, we investigated whether the tricyclic antidepressant (TCA) amitriptyline induces Egr-1 expression in astrocytes using rat C6 glioma cells as a model. We found that amitriptyline increased the expression of Egr-1 in a dose- and time-dependent manner. The amitriptyline-induced Egr-1 expression was mediated through serum response elements (SREs) in the Egr-1 promoter. SREs were activated by the Ets-domain transcription factor Elk-1 through the ERK and JNK mitogen-activated protein (MAP) kinase pathways. The inhibition of the ERK and JNK MAP kinase signals attenuated amitriptyline-induced transactivation of Gal4-Elk-1 and Egr-1 promoter activity. Our findings suggest that the induction of Egr-1 expression in astrocytes may be required to attain the therapeutic effects of antidepressant drugs.

TLR4 induces CREB-mediated IL-6 production via upregulation of F-spondin to promote vascular smooth muscle cell migration

Energy Technology Data Exchange (ETDEWEB)

Lee, Guan-Lin [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Wu, Jing-Yiing [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Yeh, Chang-Ching [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Kuo, Cheng-Chin, E-mail: kuocc@nhri.org.tw [Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan (China); Graduate Institutes of Life Sciences, National Defense Medical Center, Taipei, Taiwan (China); Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China)

2016-05-13

Toll-like receptor 4 (TLR4) is important in promoting inflammation and vascular smooth muscle cell (VSMC) migration, both of which contribute to atherosclerosis development and progression. But the mechanism underlying the regulation of TLR4 in VSMC migration remains unclear. Stimulation of VSMCs with LPS increased the cellular level of F-spondin which is associated with the regulation of proinflammatory cytokine production. The LPS-induced F-spondin expression depended on TLR4-mediated PI3K/Akt pathway. Suppression of F-spondin level by siRNA inhibited not only F-spondin expression but also LPS-induced phosphorylation of cAMP response element binding protein (CREB) and IL-6 expression, VSMC migration and proliferation as well as MMP9 expression. Moreover, suppression of CREB level by siRNA inhibited TLR4-induced IL-6 production and VSMC migration. Inhibition of F-spondin siRNA on LPS-induced migration was restored by addition of exogenous recombinant mouse IL-6. We conclude that upon ligand binding, TLR4 activates PI3K/Akt signaling to induce F-spondin expression, subsequently control CREB-mediated IL-6 production to promote VSMC migration. These findings provide vital insights into the essential role of F-spondin in VSMC function and will be valuable for developing new therapeutic strategies against atherosclerosis. -- Highlights: •LPS-induced F-spondin expression of VSMCs is via a TLR4/PI3K/Akt signaling. •F-spondin is pivotal for LPS-induced CREB-mediated IL-6 production. •F-spondin is required for LPS-induced VSMC migration and proliferation.

TLR4 induces CREB-mediated IL-6 production via upregulation of F-spondin to promote vascular smooth muscle cell migration

International Nuclear Information System (INIS)

Lee, Guan-Lin; Wu, Jing-Yiing; Yeh, Chang-Ching; Kuo, Cheng-Chin

2016-01-01

Toll-like receptor 4 (TLR4) is important in promoting inflammation and vascular smooth muscle cell (VSMC) migration, both of which contribute to atherosclerosis development and progression. But the mechanism underlying the regulation of TLR4 in VSMC migration remains unclear. Stimulation of VSMCs with LPS increased the cellular level of F-spondin which is associated with the regulation of proinflammatory cytokine production. The LPS-induced F-spondin expression depended on TLR4-mediated PI3K/Akt pathway. Suppression of F-spondin level by siRNA inhibited not only F-spondin expression but also LPS-induced phosphorylation of cAMP response element binding protein (CREB) and IL-6 expression, VSMC migration and proliferation as well as MMP9 expression. Moreover, suppression of CREB level by siRNA inhibited TLR4-induced IL-6 production and VSMC migration. Inhibition of F-spondin siRNA on LPS-induced migration was restored by addition of exogenous recombinant mouse IL-6. We conclude that upon ligand binding, TLR4 activates PI3K/Akt signaling to induce F-spondin expression, subsequently control CREB-mediated IL-6 production to promote VSMC migration. These findings provide vital insights into the essential role of F-spondin in VSMC function and will be valuable for developing new therapeutic strategies against atherosclerosis. -- Highlights: •LPS-induced F-spondin expression of VSMCs is via a TLR4/PI3K/Akt signaling. •F-spondin is pivotal for LPS-induced CREB-mediated IL-6 production. •F-spondin is required for LPS-induced VSMC migration and proliferation.

Cobalt Alloy Implant Debris Induces Inflammation and Bone Loss Primarily through Danger Signaling, Not TLR4 Activation: Implications for DAMP-ening Implant Related Inflammation

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Samelko, Lauryn; Landgraeber, Stefan; McAllister, Kyron; Jacobs, Joshua; Hallab, Nadim James

2016-01-01

Cobalt alloy debris has been implicated as causative in the early failure of some designs of current total joint implants. The ability of implant debris to cause excessive inflammation via danger signaling (NLRP3 inflammasome) vs. pathogen associated pattern recognition receptors (e.g. Toll-like receptors; TLRs) remains controversial. Recently, specific non-conserved histidines on human TLR4 have been shown activated by cobalt and nickel ions in solution. However, whether this TLR activation is directly or indirectly an effect of metals or secondary endogenous alarmins (danger-associated molecular patterns, DAMPs) elicited by danger signaling, remains unknown and contentious. Our study indicates that in both a human macrophage cell line (THP-1) and primary human macrophages, as well as an in vivo murine model of inflammatory osteolysis, that Cobalt-alloy particle induced NLRP3 inflammasome danger signaling inflammatory responses were highly dominant relative to TLR4 activation, as measured respectively by IL-1β or TNF-α, IL-6, IL-10, tissue histology and quantitative bone loss measurement. Despite the lack of metal binding histidines H456 and H458 in murine TLR4, murine calvaria challenge with Cobalt alloy particles induced significant macrophage driven in vivo inflammation and bone loss inflammatory osteolysis, whereas LPS calvaria challenge alone did not. Additionally, no significant increase (p500pg/mL). Therefore, not only do the results of this investigation support Cobalt alloy danger signaling induced inflammation, but under normal homeostasis low levels of hematogenous PAMPs (<2pg/mL) from Gram-negative bacteria, seem to have negligible contribution to the danger signaling responses elicited by Cobalt alloy metal implant debris. This suggests the unique nature of Cobalt alloy particle bioreactivity is strong enough to illicit danger signaling that secondarily activate concomitant TLR activation, and may in part explain Cobalt particulate associated

Treating Chronic Tension-type Headache Not Responding to Amitriptyline Hydrochloride With Paroxetine Hydrochloride: A Pilot Evaluation

Science.gov (United States)

Holroyd, Kenneth A.; Labus, Jennifer S.; O'Donnell, Francis J.; Cordingley, Gary E.

2007-01-01

Context In some individuals, chronic tension-type headache fails to respond to tricyclic antidepressant medications that often serve as first-line therapy. Objective To evaluate the clinical efficacy of paroxetine hydrochloride for chronic tension-type headache not responding to amitriptyline hydrochloride. Design and Setting Open-label trial of paroxetine conducted at 2 outpatient sites in Ohio. Participants and Intervention Thirty-one adults (mean age, 37 years; 20 women) with chronic tension-type headache (mean, 25 headache days per month) who had failed to respond (less than 30% improvement) to treatment with either amitriptyline (n = 13) or matched placebo (n = 18). All participants were treated with paroxetine (up to 40 mg per day) in a 9-month protocol. Outcome Measures Monthly headache index calculated as the mean of pain ratings (0 to 10 scale) recorded by participants in a diary 4 times per day, number of days per month with at least moderate pain (pain rating of 5 or greater), and analgesic medication use. Results In patients who had not responded to amitriptyline, paroxetine failed to reduce chronic tension-type headaches or analgesic medication use. In patients who had not responded to placebo, paroxetine produced modest reductions in chronic tension-type headaches and analgesic use. Conclusions We found no evidence that chronic tension-type headaches that failed to respond to tricyclic antidepressant therapy with amitriptyline improved when subsequently treated with paroxetine. More support was found for the efficacy of paroxetine in patients with chronic tension-type headaches who had failed to respond to placebo. PMID:14511278

Analysis of the antinociceptive interactions in two-drug combinations of gabapentin, oxcarbazepine and amitriptyline in streptozotocin-induced diabetic mice.

Science.gov (United States)

Tomić, Maja A; Vucković, Sonja M; Stepanović-Petrović, Radica M; Micov, Ana M; Ugresić, Nenad D; Prostran, Milica S; Bosković, Bogdan

2010-02-25

Antiepileptic and antidepressant drugs are the primary treatments for pain relief in diabetic neuropathy. Combination therapy is a valid approach in pain treatment, where a reduction of doses could reduce side effects and still achieve optimal analgesia. We examined the effects of two-drug combinations of gabapentin, oxcarbazepine, and amitriptyline on nociception in diabetic mice and aimed to determine the type of interaction between components. The nociceptive responses in normal and diabetic mice were assessed by the tail-flick test. The testing was performed before and three weeks after the diabetes induction with streptozotocin (150mg/kg; i.p.), when the antinociceptive effects of gabapentin, oxcarbazepine, amitriptyline and their two-drug combinations were examined. Gabapentin (10-40mg/kg; p.o.) and oxcarbazepine (20-80mg/kg; p.o.) produced a significant, dose-dependent antinociception in diabetic mice while amitriptyline (5-60mg/kg; p.o.) produced weak antinociceptive effect. In normal mice, neither of the drugs produced antinociception. Gabapentin and oxcarbazepine, co-administered in fixed-dose fractions of the ED(50) to diabetic mice, induced significant, dose-dependent antinociception. Isobolographic analysis revealed synergistic interaction. Oxcarbazepine (10-60mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) and gabapentin (10-30mg/kg; p.o.)+amitriptyline (5mg/kg; p.o.) combinations significantly and dose-dependently reduced nociception in diabetic mice. Analysis of the log dose-response curves for oxcarbazepine or gabapentin in a presence of amitriptyline and oxcarbazepine or gabapentin applied alone, revealed a synergism in oxcarbazepine-amitriptyline and additivity in gabapentin-amitriptyline combination. These findings provide new information about the combination therapy of painful diabetic neuropathy and should be explored further in patients with diabetic neuropathy.

An investigation on in vitro and in vivo antimicrobial properties of the antidepressant: amitriptyline hydrochloride

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Anurup Mandal

2010-10-01

Full Text Available The antidepressant drug amitriptyline hydrochloride was obtained in a dry powder form and was screened against 253 strains of bacteria which included 72 Gram positive and 181 Gram negative bacteria and against 5 fungal strains. The minimum inhibitory concentration (MIC was determined by inoculating a loopful of an overnight peptone water culture of the organism on nutrient agar plates containing increasing concentrations of amitriptyline hydrochloride (0, 10 µg/mL, 25 µg/mL, 50 µg/mL, 100 µg/mL, 200 µg/mL. Amitriptyline hydrochloride exhibited significant action against both Gram positive and Gram negative bacteria at 25-200 µg/mL. In the in vivo studies it was seen that amitriptyline hydrochloride at a concentration of 25 µg/g and 30 µg/g body weight of mouse offered significant protection to Swiss strain of white mice when challenged with 50 median lethal dose (MLD of a virulent strain of Salmonella typhimurium NCTC 74. The in vivo data were highly significant (p<0.001 according to the chi-square test.

Dexmedetomidine Inhibits Inflammatory Reaction in Lung Tissues of Septic Rats by Suppressing TLR4/NF-κB Pathway

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Yuqing Wu

2013-01-01

and 20 μg/kg significantly decreased mortality and pulmonary inflammation of septic rats, as well as suppressed CLP-induced elevation of TNF-α and IL-6 and inhibited TLR4/MyD88 expression and NF-κB activation. These results suggest that dexmedetomidine may decrease mortality and inhibit inflammatory reaction in lung tissues of septic rats by suppressing TLR4/MyD88/NF-κB pathway.

Lipid raft localization of TLR2 and its co-receptors is independent of membrane lipid composition

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Christine Hellwing

2018-01-01

Full Text Available Background Toll like receptors (TLRs are an important and evolutionary conserved class of pattern recognition receptors associated with innate immunity. The recognition of Gram-positive cell wall constituents strongly depends on TLR2. In order to be functional, TLR2 predominantly forms a heterodimer with TLR1 or TLR6 within specialized membrane microdomains, the lipid rafts. The membrane lipid composition and the physicochemical properties of lipid rafts are subject to modification by exogenous fatty acids. Previous investigations of our group provide evidence that macrophage enrichment with polyunsaturated fatty acids (PUFA induces a reordering of lipid rafts and non-rafts based on the incorporation of supplemented PUFA as well as their elongation and desaturation products. Methods In the present study we investigated potential constraining effects of membrane microdomain reorganization on the clustering of TLR2 with its co-receptors TLR1 and TLR6 within lipid rafts. To this end, RAW264.7 macrophages were supplemented with either docosahexaenoic acid (DHA or arachidonic acid (AA and analyzed for receptor expression and microdomain localization in context of TLR stimulation. Results and Conclusions Our analyses showed that receptor levels and microdomain localization were unchanged by PUFA supplementation. The TLR2 pathway, in contrast to the TLR4 signaling cascade, is not affected by exogenous PUFA at the membrane level.

Activated human neonatal CD8+ T cells are subject to immunomodulation by direct TLR2 or TLR5 stimulation.

LENUS (Irish Health Repository)

McCarron, Mark

2012-02-01

In conditions of optimal priming, the neonate possesses competency to mount quantitatively adult-like responses. Vaccine formulations containing sufficiently potent adjuvants may overcome the neonate\\'s natural tendency for immunosuppression and provoke a similarly robust immune response. TLR expression on T cells represents the possibility of directly enhancing T cell immunity. We examined the ex vivo responsiveness of highly purified human cord blood-derived CD8(+) T cells to direct TLR ligation by a repertoire of TLR agonists. In concert with TCR stimulation, only Pam(3)Cys (palmitoyl-3-Cys-Ser-(Lys)(4)) and flagellin monomers significantly enhanced proliferation, CD25(+) expression, IL-2, IFN-gamma, TNF-alpha, and intracellular granzyme B expression. TLR2 and TLR5 mRNA was detected in the CD8(+) T cells. Blocking studies confirmed that the increase in IFN-gamma production was by the direct triggering of surface TLR2 or TLR5. The simultaneous exposure of CD8(+) T cells to both TLR agonists had an additive effect on IFN-gamma production. These data suggest that a combination of the two TLR ligands would be a potent T cell adjuvant. This may represent a new approach to TLR agonist-based adjuvant design for future human neonatal vaccination strategies requiring a CD8(+) component.

A Brief Review of the Pharmacology of Amitriptyline and Clinical Outcomes in Treating Fibromyalgia

OpenAIRE

Kim Lawson

2017-01-01

Fibromyalgia is a complex chronic condition characterized by pain, physical fatigue, sleep disorder and cognitive impairment. Evidence-based guidelines recommend antidepressants as treatments of fibromyalgia where tricyclics are often considered to have the greatest efficacy, with amitriptyline often being a first-line treatment. Amitriptyline evokes a preferential reduction in pain and fatigue of fibromyalgia, and in the Fibromyalgia Impact Questionnaire (FIQ) score, which is a quality of li...

Evaluation of the effect of locally administered amitriptyline gel as adjunct to local anesthetics in irreversible pulpitis pain

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Moghadamnia A

2009-01-01

Full Text Available Background: Amitriptyline is one of the most common tricyclic antidepressants, which binds to pain sensory nerve fibers close to the sodium channel; hence, it could interact to some degree with receptors of local anesthetics. This study was designed to assess the additional analgesic effects of 2% Amitriptyline local gel administration in irreversible pulpitis pain of the molars. Materials and Methods: This study was a randomized, double-blind clinical trial that was performed on 56 consented adult patients who did not receive enough analgesia after a lidocaine nerve block for their tooth pulpitis pain. Patients were treated with 0.2 ml of either 2% amitriptyline or placebo, which was directly injected into their mandibular molar pulp chamber after they had received two routine lidocaine injections. Patients were asked to score their pain as a mark on a 10-cm Visual Analogue Scale (VAS at different timepoints: 0 (just before gel administration, 1, 3, 5, 7, and 9 minutes after the treatments. Results: There was a 92.5% decrease in VAS scores of patients 9 minutes after amitriptyline administration compared to Time 0, while in the placebo group this difference was only 13.5%. Further, in the amitriptyline group, the VAS score at all timepoints was statistically different from Time 0 ( P < 0.01. The overall pain reduction and its trend was significantly higher in the amitriptyline group compared with the placebo group ( P < 0.001. Conclusion: Inter-pulp space administration of amitriptyline 2% gel for completing analgesia in irreversible pulpitis pain could be effective and useful as a conjunctive therapy to injections of local anesthetics.

The role of TLR4 896 A>G and 1196 C>T in susceptibility to infections: a review and meta-analysis of genetic association studies.

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Panayiotis D Ziakas

Full Text Available BACKGROUND: Toll-like receptor 4 plays a role in pathogen recognition, and common polymorphisms may alter host susceptibility to infectious diseases. PURPOSE: To review the association of two common polymorphisms (TLR4 896A>G and TLR4 1196C>T with infectious diseases. DATA SOURCES: We searched PubMed and EMBASE up to March 2013 for pertinent literature in English, and complemented search with references lists of eligible studies. STUDY SELECTION: We included all studies that: reported an infectious outcome; had a case-control design and reported the TLR4 896A>G and/or TLR4 1196C>T genotype frequencies; 59 studies fulfilled these criteria and were analyzed. DATA EXTRACTION: Two authors independently extracted study data. DATA SYNTHESIS: The generalized odds ratio metric (ORG was used to quantify the impact of TLR4 variants on disease susceptibility. A meta-analysis was undertaken for outcomes reported in >1 study. Eleven of 37 distinct outcomes were significant. TLR4 896 A>G increased risk for all parasitic infections (ORG 1.59; 95%CI 1.05-2.42, malaria (1.31; 95%CI 1.04-1.66, brucellosis (2.66; 95%CI 1.66-4.27, cutaneous leishmaniasis (7.22; 95%CI 1.91-27.29, neurocysticercosis (4.39; 95%CI 2.53-7.61, Streptococcus pyogenes tonsillar disease (2.93; 95%CI 1.24-6.93 , typhoid fever (2.51; 95%CI 1.18-5.34 and adult urinary tract infections (1.98; 95%CI 1.04-3.98, but was protective for leprosy (0.36; 95%CI 0.22-0.60. TLR4 1196 C>T effects were similar to TLR4 896 A>G for brucellosis, cutaneous leishmaniasis, leprosy, typhoid fever and S. pyogenes tonsillar disease, and was protective for bacterial vaginosis in pregnancy (0.55; 95%CI 0.31-0.98 and Haemophilus influenzae tonsillar disease (0.42; 95%CI 0.17-1.00. The majority of significant associations were among predominantly Asian populations and significant associations were rare among European populations. CONCLUSIONS: Depending on the type of infection and population, TLR4 polymorphisms are

Hypoacylated LPS from Foodborne Pathogen Campylobacter jejuni Induces Moderate TLR4-Mediated Inflammatory Response in Murine Macrophages.

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Korneev, Kirill V; Kondakova, Anna N; Sviriaeva, Ekaterina N; Mitkin, Nikita A; Palmigiano, Angelo; Kruglov, Andrey A; Telegin, Georgy B; Drutskaya, Marina S; Sturiale, Luisa; Garozzo, Domenico; Nedospasov, Sergei A; Knirel, Yuriy A; Kuprash, Dmitry V

2018-01-01

Toll-like receptor 4 (TLR4) initiates immune response against Gram-negative bacteria upon specific recognition of lipid A moiety of lipopolysaccharide (LPS), the major component of their cell wall. Some natural differences between LPS variants in their ability to interact with TLR4 may lead to either insufficient activation that may not prevent bacterial growth, or excessive activation which may lead to septic shock. In this study we evaluated the biological activity of LPS isolated from pathogenic strain of Campylobacter jejuni , the most widespread bacterial cause of foodborne diarrhea in humans. With the help of hydrophobic chromatography and MALDI-TOF mass spectrometry we showed that LPS from a C. jejuni strain O2A consists of both hexaacyl and tetraacyl forms. Since such hypoacylation can result in a reduced immune response in humans, we assessed the activity of LPS from C. jejuni in mouse macrophages by measuring its capacity to activate TLR4-mediated proinflammatory cytokine and chemokine production, as well as NFκB-dependent reporter gene transcription. Our data support the hypothesis that LPS acylation correlates with its bioactivity.

TLR4 Gene Expression and Pro-Inflammatory Cytokines in Alzheimer's Disease and in Response to Hippocampal Deafferentation in Rodents.

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Miron, Justin; Picard, Cynthia; Frappier, Josée; Dea, Doris; Théroux, Louise; Poirier, Judes

2018-01-01

One important aspect in Alzheimer's disease pathology is the presence of chronic inflammation. Considering its role as a key receptor in the microglial innate immune system, TLR4 was shown to regulate the binding and phagocytosis of amyloid plaques by microglia in several mouse models of amyloidosis, as well as the production of pro-inflammatory cytokines. To our knowledge, TLR4 and its association with cytokines have not been thoroughly examined in the brains of subjects affected with Alzheimer's disease. Using quantitative reverse transcription polymerase chain reaction (qRT-PCR) in postmortem human brains, we observed increased expression for the TLR4 and TNF genes (p = 0.001 and p = 0.025, respectively), as well as a trend for higher IL6 gene expression in the frontal cortex of AD subjects when compared to age-matched controls. Similarly, using a mouse model of hippocampal deafferentation without amyloidosis, (i.e., the entorhinal cortex lesioned mouse), we observed significant increases in the expression of both the Tlr4 (p = 0.0367 and p = 0.0193 compared to sham-lesioned mice or to the contralateral side, respectively) and Il1b (p = 0.0055 and p = 0.0066 compared to sham-lesioned mice or to the contralateral side, respectively) genes in the deafferentation phase, but not during the ensuing reinnervation process. In conclusion, we suggest that the modulation of cytokines by TLR4 is differentially regulated whether by the presence of amyloid plaques or by the ongoing deafferentation process.

DMPD: LPS, TLR4 and infectious disease diversity. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available Nat Rev Microbiol. 2005 Jan;3(1):36-46. (.png) (.svg) (.html) (.csml) Show LPS, TLR4 and infectious disease... (.png) SVG File (.svg) HTML File (.html) CSML File (.csml) Open .csml file with CIOPlayer Open .csml file w

Induction of TLR-2 and TLR-5 expression by Helicobacter pylori switches cagPAI-dependent signalling leading to the secretion of IL-8 and TNF-α.

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Suneesh Kumar Pachathundikandi

2011-05-01

Full Text Available Helicobacter pylori is the causative agent for developing gastritis, gastric ulcer, and even gastric cancer. Virulent strains carry the cag pathogenicity island (cagPAI encoding a type-IV secretion system (T4SS for injecting the CagA protein. However, mechanisms of sensing this pathogen through Toll-like receptors (TLRs and downstream signalling pathways in the development of different pathologies are widely unclear. Here, we explored the involvement of TLR-2 and TLR-5 in THP-1 cells and HEK293 cell lines (stably transfected with TLR-2 or TLR-5 during infection with wild-type H. pylori and isogenic cagPAI mutants. H. pylori triggered enhanced TLR-2 and TLR-5 expression in THP-1, HEK293-TLR2 and HEK293-TLR5 cells, but not in the HEK293 control. In addition, IL-8 and TNF-α cytokine secretion in THP-1 cells was induced in a cagPAI-dependent manner. Furthermore, we show that HEK293 cells are not competent for the uptake of T4SS-delivered CagA, and are therefore ideally suited for studying TLR signalling in the absence of T4SS functions. HEK293 control cells, which do not induce TLR-2 and TLR-5 expression during infection, only secreted cytokines in small amounts, in agreement with T4SS functions being absent. In contrast, HEK293-TLR2 and HEK293-TLR5 cells were highly competent for inducing the secretion of IL-8 and TNF-α cytokines in a cagPAI-independent manner, suggesting that the expression of TLR-2 or TLR-5 has profoundly changed the capability to trigger pro-inflammatory signalling upon infection. Using phospho-specific antibodies and luciferase reporter assays, we further demonstrate that H. pylori induces IRAK-1 and IκB phosphorylation in a TLR-dependent manner, and this was required for activation of transcription factor NF-κB. Finally, NF-κB activation in HEK293-TLR2 and HEK293-TLR5 cells was confirmed by expressing p65-GFP which was translocated from the cytoplasm into the nucleus. These data indicate that H. pylori-induced expression

Atopy and new-onset asthma in young Danish farmers and CD14, TLR2, and TLR4 genetic polymorphisms: a nested case-control study

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Smit, L A M; Bongers, S I M; Ruven, H J T

2007-01-01

BACKGROUND: Evidence exists that exposure to high levels of microbial agents such as endotoxin in the farm environment decreases the risk of atopic sensitization. Genetic variation in innate immunity genes may modulate the response to microbial agents and thus influence susceptibility to asthma...... and atopy. OBJECTIVE: To study potential associations between single nucleotide polymorphisms (SNPs) in CD14, Toll-like receptor 2 (TLR2), and TLR4 genes, and atopy and new-onset asthma in young farmers. METHODS: A nested case-control study was conducted within a cohort of 1901 young Danish farmers. We....../-651 promoter polymorphisms are associated with atopy prevalence among young adults exposed to farm environments. Udgivelsesdato: 2007-Nov...

Identification, characterization and genetic mapping of TLR7, TLR8a1 and TLR8a2 genes in rainbow trout (Oncorhynchus mykiss)

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Palti, Yniv; Gahr, Scott A.; Purcell, Maureen K.; Hadidi, Sima; Rexroad, Caird E.; Wiens, Gregory A.

2010-01-01

Induction of the innate immune pathways is critical for early anti-viral defense but there is limited understanding of how teleost fish recognize viral molecules and activate these pathways. In mammals, Toll-like receptors (TLR) 7 and 8 bind single-stranded RNA of viral origin and are activated by synthetic anti-viral imidazoquinoline compounds. Herein, we identify and describe the rainbow trout (Oncorhynchus mykiss) TLR7 and TLR8 gene orthologs and their mRNA expression. Two TLR7/8 loci were identified from a rainbow trout bacterial artificial chromosome (BAC) library using DNA fingerprinting and genetic linkage analyses. Direct sequencing of two representative BACs revealed intact omTLR7 and omTLR8a1 open reading frames (ORFs) located on chromosome 3 and a second locus on chromosome 22 that contains an omTLR8a2 ORF and a putative TLR7 pseudogene. We used the omTLR8a1/2 nomenclature for the two trout TLR8 genes as phylogenetic analysis revealed that they and all the other teleost TLR8 genes sequenced to date are similar to the zebrafish TLR8a, but are distinct from the zebrafish TLR8b. The duplicated trout loci exhibit conserved synteny with other fish genomes extending beyond the tandem of TLR7/8 genes. The trout TLR7 and 8a1/2 genes are composed of a single large exon similar to all other described TLR7/8 genes. The omTLR7 ORF is predicted to encode a 1049 amino acid (aa) protein with 84% similarity to the Fugu TLR7 and a conserved pattern of predicted leucine-rich repeats (LRR). The omTLR8a1 and omTLR8a2 are predicted to encode 1035- and 1034-aa proteins, respectively, and have 86% similarity to each other. omTLR8a1 is likely the ortholog of the only Atlantic salmon TLR8 gene described to date as they have 95% aa sequence similarity. The tissue expression profiles of omTLR7, omTLR8a1 and omTLR8a2 in healthy trout were highest in spleen tissue followed by anterior and then posterior kidney tissues. Rainbow trout anterior kidney leukocytes produced elevated

Positive Correlation between Enhanced Expression of TLR4/MyD88/NF-κB with Insulin Resistance in Placentae of Gestational Diabetes Mellitus.

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Hui Feng

Full Text Available Insulin resistance (IR is a critical factor of the pathophysiology of Gestational diabetes mellitus (GDM. Studies on key organs involved in IR, such as livers and adipose tissues, showed that Toll-like receptor 4 (TLR4 can regulate insulin sensitivity. As a maternal-fetal interface with multi-functions, placentae could contribute to the development of IR for GDM. Thus, we investigated the expressions of TLR4/Myeloid Differentiation factor 88 (MyD88/Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-kB in term placentae from 33 GDM women and 36 healthy pregnant women with normal glucose tolerance, evaluated local and systemic IR and furthermore identified the association between placental TLR4 and IR. TLR4 protein was expressed in various cells of term placenta, particularly in syncytiotrophoblast of villi. Compared with normal pregnancy, the expression of TLR4/MyD88/NF-kB pathway increased in the placenta of GDM (p<0.05, and these differences were more pronounced in the maternal section of the placenta and the syncytiotrophoblast of villi. In addition, more severe IR was observed in the placenta of GDM patients than the control group, evidenced with higher pIRS-1(ser312 (p<0.001 and lower IRS-1 (p<0.05 as well as pAkt proteins (p<0.01. The expression of TLR4 in placentae is positively correlated with local IR (pIRS-1: r = 0.76, p <0.001 and pAkt: r = -0.47, p <0.001 and maternal fasting (r = 0.42, p <0.01, one-hour (r = 0.52, p <0.01 and two-hour glucose (r = 0.54, p <0.01 at OGTT. We found an that enhanced expression of the TLR4-MyD88-NF-kB pathway occurs in GDM placentae, which positively correlates with heightened local IR in placentae and higher maternal hyperglycemia. The TLR4/MyD88/NF-kB pathway may play a potential role in the development of IR in placentae of GDM.

RP105 Protects Against Apoptosis in Ischemia/Reperfusion-Induced Myocardial Damage in Rats by Suppressing TLR4-Mediated Signaling Pathways

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Jun Yang

2015-07-01

Full Text Available Background: Myocardial apoptosis is heavily implicated in the myocardial damage caused by ischemia-reperfusion (I/R. Toll-like receptor 4 (TLR4 is a potent inducer of these apoptotic cascades. In contrast, the radioprotective 105 kDa protein (RP105 is a specific negative regulator of TLR4 signaling pathways. However, the precise mechanisms by which RP105 inhibits myocardium apoptosis via TLR4-associated pathways during I/R is not fully understood. Methods: We utilized a rat model of myocardial ischemic reperfusion injury (MIRI. Animals were pre-treated with Ad-EGFP adenovirus, Ad-EGFP-RP105 adenovirus, saline, or nothing (sham. After three days, rats underwent a 30min left anterior descending coronary artery occlusion and a 4h reperfusion. Mycardial tissue was assessed by immunohistochemistry, TUNEL-staining, Western blot, quantitative RT-PCR, and a morphometric assay. Results: RP105 overexpression resulted in a reduction in infarct size, fewer TUNEL-positive cardiomyocytes, and a reduction in mitochondrial-associated apoptosis cascade activity. Further, RP105 overexpression repressed I/R-induced myocardial injury by attenuating myocardial apoptosis. This was mediated by inhibiting TLR4 activation and the phosphorylation of P38MAPK and the downstream transcription factor AP-1. Conclusion: RP105 overexpression leads to the de-activation of TLR4, P38MAPK, and AP-1 signaling pathways, and subsequently represses apoptotic cascades and ensuing damage of myocardial ischemic reperfusion. These findings may become the basis of a novel therapeutic approach for reducing of cardiac damage caused by MIRI.

Intra-oral orthosis vs amitriptyline in chronic tension-type headache: a clinical and laser evoked potentials study

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Sardaro Michele

2006-05-01

Full Text Available Abstract Background In the present study, we examined clinical and laser-evoked potentials (LEP features in two groups of chronic tension-type headache (CTTH patients treated with two different approaches: intra-oral appliance of prosthesis, aiming to reduce muscular tenderness, and 10 mg daily amitriptyline. Methods Eighteen patients with diagnosed CTTH participated in this open label, controlled study. A baseline evaluation was performed for clinical features, Total Tenderness Score (TTS and a topographic analysis of LEPs obtained manually and the pericranial points stimulation in all patients vs. healthy subjects. Thereafter, patients were randomly assigned to a two-month treatment by either amitriptyline or intra-oral appliance. Results and discussion Both the intra-oral appliance and amitriptyline significantly reduced headache frequency. The TTS was significantly reduced in the group treated with the appliance. The amplitude of P2 response elicited by stimulation of pericranial zones showed a reduction after amitriptyline treatment. Both therapies were effective in reducing headache severity, the appliance with a prevalent action on the pericranial muscular tenderness, amitriptyline reducing the activity of the central cortical structures subtending pain elaboration Conclusion The results of this study may suggest that in CTTH both the interventions at the peripheral and central levels improve the outcome of headache.

Effects of amitriptyline and fluoxetine on synaptic plasticity in the dentate gyrus of hippocampal formation in rats

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Ghasem Zarei

2014-01-01

Full Text Available Background: Several studies have been shown that antidepressant drugs have contradictory effects on cognitive processes. Therefore, the aim of this study was to investigate the effects of amitriptyline and fluoxetine on synaptic plasticity in the dentate gyrus (DG of the hippocampal formation in rat. Materials and Methods: Experimental groups were the control, the fluoxetine, and amitriptyline. The rats were treated for 21 days and then, paired pulse facilitation/inhibition (PPF/I and long-term potentiation (LTP in perforant path-DG synapses were assessed (by 400 Hz tetanization. Field excitatory post-synaptic potential (fEPSP slope and population spike (PS amplitude were measured. Results: The results of PPF/I showed that PS amplitude ratios were increased in 10-70 ms inter-stimulus intervals in the amitriptyline group compared to the control group. In the fluoxetine group, EPSP slope ratios were decreased in intervals 30, 40, and 50 ms inter-stimulus intervals compared to the control group. The PS-LTP was significantly lower in the fluoxetine and the amitriptyline groups with respect to the control group. Conclusion: The results showed that fluoxetine and amitriptyline affect synaptic plasticity in the hippocampus and these effects is probably due to the impact on the number of active neurons.

Effect of amitriptyline vs. physiotherapy in management of fibromyalgia syndrome: What predicts a clinical benefit?

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Joshi M

2009-01-01

Full Text Available Context : Fibromyalgia is a chronic disabling condition, and physicians treat it using a number of different treatment modalities. It is not known if one or more of such modalities are better than the others. We compared the efficacy of physiotherapy and amitriptyline in disability reduction in patients of fibromyalgia syndrome in a rural tertiary care hospital in Central India. Design : Open-label alternate patient treatment allocation. Materials and Methods : A six-month follow-up was done to assess the benefit of amitriptyline and physiotherapy for disability reduction in patients with fibromyalgia syndrome. Primary outcome measure was improvement in fibromyalgia impact questionnaire (FIQ score. Statistical Analysis Used : Predictors of benefit were determined using multivariate logistic regression. Results : A total of 175 outpatients were assigned to either amitriptyline (n=87 or structured physiotherapy (n=88 treatments. There was a significant but similar (P=0.82 improvement in disability in both groups. High FIQ score at baseline and low socioeconomic status scores were significant predictors of benefit. Conclusions : Therapy with amitriptyline or physiotherapy is equally effective in improving outcome in patients of fibromyalgia over a period of six months.

Single administration of ultra-low-dose lipopolysaccharide in rat early pregnancy induces TLR4 activation in the placenta contributing to preeclampsia.

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Pingping Xue

Full Text Available Balanced immune responses are essential for the maintenance of successful pregnancy. Aberrant responses of immune system during pregnancy increase the risk of preeclampsia. Toll-like receptor 4 (TLR4 plays a crucial role in the activation of immune system at the maternal-fetal interface. This study aimed to generate a rat model of preeclampsia by lipopolysaccharide (LPS, a TLR4 agonist administration on gestational day (GD 5 as rats are subjected to placentation immediately after implantation between GDs 4 and 5, and to assess the contribution of TLR4 signaling to the development of preeclampsia. Single administration of 0.5 μg/kg LPS significantly increased blood pressure of pregnant rats since GD 6 (systolic blood pressure, 124.89 ± 1.79 mmHg versus 119.02 ± 1.80 mmHg, P < 0.05 and urinary protein level since GD 9 (2.02 ± 0.29 mg versus 1.11 ± 0.18 mg, P < 0.01, but barely affected blood pressure or proteinuria of virgin rats compared with those of saline-treated pregnant rats. This was accompanied with adverse pregnancy outcomes including fetal growth restriction. The expression of TLR4 and NF-κB p65 were both increased in the placenta but not the kidney from LPS-treated pregnant rats, with deficient trophoblast invasion and spiral artery remodeling. Furthermore, the levels of inflammatory cytokines were elevated systemically and locally in the placenta from pregnant rats treated with LPS. TLR4 signaling in the placenta was activated, to which that in the placenta of humans with preeclampsia changed similarly. In conclusion, LPS administration to pregnant rats in early pregnancy could elicit TLR4-mediated immune response at the maternal-fetal interface contributing to poor early placentation that may culminate in the preeclampsia-like syndrome.

Ginkgolide B Suppresses TLR4-Mediated Inflammatory Response by Inhibiting the Phosphorylation of JAK2/STAT3 and p38 MAPK in High Glucose-Treated HUVECs

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Kun Chen

2017-01-01

Full Text Available Aim. Ginkgolide B is a Ginkgo biloba leaf extract that has been identified as a natural platelet-activating factor receptor (PAFR antagonist. We investigated the effect of ginkgolide B on high glucose-induced TLR4 activation in human umbilical vein endothelial cells (HUVECs. Methods. Protein expression was analyzed by immunoblotting. Small-interfering RNA (siRNA was used to knock down PAFR and TLR4 expression. Results. Ginkgolide B suppressed the expression of TLR4 and MyD88 that was induced by high glucose. Ginkgolide B also reduced the levels of platelet endothelial cell adhesion molecule-1, interleukin-6, and monocyte chemotactic protein 1. Further, we examined the association between PAFR and TLR4 by coimmunoprecipitation. The result showed that high glucose treatment caused the binding of PAFR and TLR4, whereas ginkgolide B abolished this binding. The functional analysis indicated that PAFR siRNA treatment reduced TLR4 expression, and TLR4 siRNA treatment decreased PAFR expression in high glucose-treated HUVECs, further supporting the coimmunoprecipitation data. Ginkgolide B inhibited the phosphorylation of Janus kinase 2 (JAK2/signal transducer and activator of transcription 3 (STAT3 and p38 mitogen-activated protein kinase (MAPK. Conclusion. Ginkgolide B exerted protective effects by inhibiting the TLR4-mediated inflammatory response in high glucose-treated endothelial cells. The mechanism of action of ginkgolide B might be associated with inhibition of the JAK2/STAT3 and p38 MAPK phosphorylation.

Cobalt Alloy Implant Debris Induces Inflammation and Bone Loss Primarily through Danger Signaling, Not TLR4 Activation: Implications for DAMP-ening Implant Related Inflammation.

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Lauryn Samelko

Full Text Available Cobalt alloy debris has been implicated as causative in the early failure of some designs of current total joint implants. The ability of implant debris to cause excessive inflammation via danger signaling (NLRP3 inflammasome vs. pathogen associated pattern recognition receptors (e.g. Toll-like receptors; TLRs remains controversial. Recently, specific non-conserved histidines on human TLR4 have been shown activated by cobalt and nickel ions in solution. However, whether this TLR activation is directly or indirectly an effect of metals or secondary endogenous alarmins (danger-associated molecular patterns, DAMPs elicited by danger signaling, remains unknown and contentious. Our study indicates that in both a human macrophage cell line (THP-1 and primary human macrophages, as well as an in vivo murine model of inflammatory osteolysis, that Cobalt-alloy particle induced NLRP3 inflammasome danger signaling inflammatory responses were highly dominant relative to TLR4 activation, as measured respectively by IL-1β or TNF-α, IL-6, IL-10, tissue histology and quantitative bone loss measurement. Despite the lack of metal binding histidines H456 and H458 in murine TLR4, murine calvaria challenge with Cobalt alloy particles induced significant macrophage driven in vivo inflammation and bone loss inflammatory osteolysis, whereas LPS calvaria challenge alone did not. Additionally, no significant increase (p500pg/mL. Therefore, not only do the results of this investigation support Cobalt alloy danger signaling induced inflammation, but under normal homeostasis low levels of hematogenous PAMPs (<2pg/mL from Gram-negative bacteria, seem to have negligible contribution to the danger signaling responses elicited by Cobalt alloy metal implant debris. This suggests the unique nature of Cobalt alloy particle bioreactivity is strong enough to illicit danger signaling that secondarily activate concomitant TLR activation, and may in part explain Cobalt particulate

TLR3 mediates release of IL-1β and cell death in keratinocytes in a caspase-4 dependent manner.

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Grimstad, Øystein; Husebye, Harald; Espevik, Terje

2013-10-01

Inflammation and timely cell death are important elements in host defence and healing processes. Keratinocytes express high levels of Toll-like receptor 3 (TLR3), and stimulation of the receptor with its ligand polyinosinic-polycytidylic acid (polyI:C) is a powerful signal for release of a variety of proinflammatory cytokines. Caspase-4 is required for maturation of pro-IL-1β through activation of caspase-1 in keratinocytes. TLR3 in keratinocytes was stimulated with polyI:C. Induction of messenger RNA of pro-IL-1β and inflammasomal components was measured using quantitative polymerase chain reaction methodology. Protein expression of IL-1β was analysed with ELISA and Western blot techniques. Activation of apoptotic caspases was measured with flow cytometry, and cytotoxicity was determined. TLR3 induced release of substantial amounts of pro-IL-1β in keratinocytes. NLRP3 or ASC dependent processing of IL-1β into its cleaved bioactive form was found to be minimal. The release of IL-1β was due to polyI:C induced cell death that occurred through a caspase-4 dependent manner. Caspase-1 did not seem to be involved in the polyI:C induced cytotoxicity despite that TLR3 stimulation induced activation of caspase-1. In addition, the apoptotic caspases -8, -9 and -3/7 were activated by polyI:C. TLR3 stimulation in keratinocytes induces a caspase-4 dependent release of pro-IL-1β, but further processing to active IL-1β is limited. Furthermore, TLR3 stimulation results in pyroptotic- and apoptotic cell death. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Amitriptyline-mediated cognitive enhancement in aged 3×Tg Alzheimer's disease mice is associated with neurogenesis and neurotrophic activity.

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Wayne Chadwick

Full Text Available Approximately 35 million people worldwide suffer from Alzheimer's disease (AD. Existing therapeutics, while moderately effective, are currently unable to stem the widespread rise in AD prevalence. AD is associated with an increase in amyloid beta (Aβ oligomers and hyperphosphorylated tau, along with cognitive impairment and neurodegeneration. Several antidepressants have shown promise in improving cognition and alleviating oxidative stress in AD but have failed as long-term therapeutics. In this study, amitriptyline, an FDA-approved tricyclic antidepressant, was administered orally to aged and cognitively impaired transgenic AD mice (3×TgAD. After amitriptyline treatment, cognitive behavior testing demonstrated that there was a significant improvement in both long- and short-term memory retention. Amitriptyline treatment also caused a significant potentiation of non-toxic Aβ monomer with a concomitant decrease in cytotoxic dimer Aβ load, compared to vehicle-treated 3×TgAD controls. In addition, amitriptyline administration caused a significant increase in dentate gyrus neurogenesis as well as increases in expression of neurosynaptic marker proteins. Amitriptyline treatment resulted in increases in hippocampal brain-derived neurotrophic factor protein as well as increased tyrosine phosphorylation of its cognate receptor (TrkB. These results indicate that amitriptyline has significant beneficial actions in aged and damaged AD brains and that it shows promise as a tolerable novel therapeutic for the treatment of AD.

Amitriptyline versus placebo for major depression

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Kessing, Lars Vedel; Bukh, Jens Otto Drachmann

2013-01-01

A recent Cochrane review concluded that amitriptyline is an efficacious antidepressant drug, however associated with a number of side effects. The present paper discusses this finding in relation to studies on effects and side effects of SSRIs and dual-action drugs. It is concluded that there is ...... that there is some evidence for recommending treatment with tricyclic antidepressants (TCA) especially in patients who are hospitalized with severe depression and melancholic features. Further, nortriptylin is preferred due to its more favourable side effects profile....

Amitriptyline is efficacious in ameliorating muscle inflammation and depressive symptoms in the mdx mouse model of Duchenne muscular dystrophy.

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Manning, Jennifer; Kulbida, Rebecca; Rai, Prerana; Jensen, Lindsay; Bouma, Judith; Singh, Sanjay P; O'Malley, Dervla; Yilmazer-Hanke, Deniz

2014-10-01

Mutations in the structural protein dystrophin underlie muscular dystrophies characterized by progressive deterioration of muscle function. Dystrophin-deficient mdx mice are considered a model for Duchenne muscular dystrophy (DMD). Individuals with DMD are also susceptible to mood disorders, such as depression and anxiety. Therefore, the study objectives were to investigate the effects of the tricyclic antidepressant amitriptyline on mood, learning, central cytokine expression and skeletal muscle inflammation in mdx mice. Amitriptyline-induced effects (10 mg kg(-1) daily s.c. injections, 25 days) on the behaviour of mdx mice were investigated using the open field arena and tail suspension tests. The effects of chronic amitriptyline treatment on inflammatory markers were studied in the muscle and plasma of mdx mice, and mood-associated monoamine and cytokine concentrations were measured in the amygdala, hippocampus, prefrontal cortex, striatum, hypothalamus and midbrain. The mdx mice exhibited increased levels of anxiety and depressive-like behaviour compared with wild-type mice. Amitriptyline treatment had anxiolytic and antidepressant effects in mdx mice associated with elevations in serotonin levels in the amygdala and hippocampus. Inflammation in mdx skeletal muscle tissue was also reduced following amitriptyline treatment as indicated by decreased immune cell infiltration of muscle and lower levels of the pro-inflammatory cytokines tumour necrosis factor-α and interleukin-6 in the forelimb flexors. Interleukin-6 mRNA expression was remarkably reduced in the amygdala of mdx mice by chronic amitriptyline treatment. Positive effects of amitriptyline on mood, in addition to its anti-inflammatory effects in skeletal muscle, may make it an attractive therapeutic option for individuals with DMD. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

Immunogenicity investigations of lipidoid structures in vitro and in silico: Modulating lipidoid-mediated TLR4 activation by nanoparticle design

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de Groot, Anne Marit; Thanki, Kaushik; Gangloff, Monique

2018-01-01

, we showed that encapsulation of siRNA in lipid-polymer hybrid nanoparticles (LPNs), based on poly(DL-lactic-co-glycolic acid) (PLGA) and cationic lipid-like materials (lipidoids), remarkably enhances intracellular delivery of siRNA as compared to siRNA delivery with LPNs modified...... acid lipid particles, which was the reference formulation for siRNA delivery, proved to activate TLR4. However, by combining lipidoids with PLGA into LPNs, TLR4 activation was abrogated. Thus, lipidoid-mediated TLR4 activation during siRNA delivery may be modulated via optimization of the formulation......Therapeutics based on small interfering RNA (siRNA) have promising potential as antiviral and anti-inflammatory agents. To deliver siRNA across cell membranes to reach the RNA interference pathway in the cytosol of target cells, non-viral nanoparticulate delivery approaches are explored. Recently...

Atorvastatin attenuates experimental contrast-induced acute kidney injury: a role for TLR4/MyD88 signaling pathway.

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Yue, Rongzheng; Zuo, Chuan; Zeng, Jing; Su, Baihai; Tao, Ye; Huang, Songmin; Zeng, Rui

2017-11-01

To investigate the protective effect of different atorvastatin doses on contrast-induced acute kidney injury and the related mechanism. Healthy male Sprague-Dawley (SD) rats were randomly divided into the blank control group, experimental control group and different-dose atorvastatin groups. A rat model of contrast-induced acute kidney injury was established. We detected changes in serum creatinine (Scr) and blood urea nitrogen (BUN) before and after model establishment, observed and scored renal tubular injury, analyzed rat renal cell apoptosis, and measure the expression of signal pathway proteins and downstream inflammatory factors. After contrast agent injection, the Scr and BUN levels of the experimental control group were significantly increased, the different doses applied in the atorvastatin group significantly reduced the Scr and BUN levels (p atorvastatin doses have protective effects on contrast-induced acute renal tubular injury in rats, possibly by targeting TLR4, suppressing TLR4 expression, regulating the TLR4/Myd88 signaling pathway, and inhibiting the expression of downstream inflammatory factors.

Gene conversion limits divergence of mammalian TLR1 and TLR6

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Dunoyer-Geindre Sylvie

2007-08-01

Full Text Available Abstract Background Toll-like receptors (TLR recognize pathogen-associated molecular patterns and are important mediators of the innate immune system. TLR1 and TLR6 are paralogs and located in tandem on the same chromosome in mammals. They form heterodimers with TLR2 and bind lipopeptide components of gram-positive and gram-negative bacterial cell walls. To identify conserved stretches in TLR1 and TLR6, that may be important for their function, we compared their protein sequences in nine mammalian species(Homo sapiens, Pan troglodytes, Macaca mulatta, Mus musculus, Rattus norvegicus; Erinaceus europaeus, Bos Taurus, Sus scrofa and Canis familiaris. Results The N-terminal sequences of the orthologous proteins showed greater similarity than corresponding paralog sequences. However, we identified a region of 300 amino acids towards the C-terminus of TLR1 and TLR6, where paralogs had a greater degree of sequence identity than orthologs. Preservation of DNA sequence identity of paralogs in this region was observed in all nine mammalian species investigated, and is due to independent gene conversion events. The regions having undergone gene conversion in each species are almost identical and encode the leucine-rich repeat motifs 16 to 19, the C-terminal cap motif, the transmembrane domain and most of the intracellular Toll/interleukin-1 receptor (TIR domain. Conclusion Our results show that, for a specific conserved region, divergence of TLR1 and TLR6 is limited by gene conversion, most likely because of the need for co-evolution with multiple intracellular and extracellular binding partners. Thus, gene conversion provides a mechanism for limiting the divergence of functional regions of protein paralogs, while allowing other domains to evolve diversified functions.

Tricyclic Antidepressant Amitriptyline-induced Glial Cell Line-derived Neurotrophic Factor Production Involves Pertussis Toxin-sensitive Gαi/o Activation in Astroglial Cells.

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Hisaoka-Nakashima, Kazue; Miyano, Kanako; Matsumoto, Chie; Kajitani, Naoto; Abe, Hiromi; Okada-Tsuchioka, Mami; Yokoyama, Akinobu; Uezono, Yasuhito; Morioka, Norimitsu; Nakata, Yoshihiro; Takebayashi, Minoru

2015-05-29

Further elaborating the mechanism of antidepressants, beyond modulation of monoaminergic neurotransmission, this study sought to elucidate the mechanism of amitriptyline-induced production of glial cell line-derived neurotrophic factor (GDNF) in astroglial cells. Previous studies demonstrated that an amitriptyline-evoked matrix metalloproteinase (MMP)/FGF receptor (FGFR)/FGFR substrate 2α (FRS2α)/ERK cascade is crucial for GDNF production, but how amitriptyline triggers this cascade remains unknown. MMP is activated by intracellular mediators such as G proteins, and this study sought to clarify the involvement of G protein signaling in amitriptyline-evoked GDNF production in rat C6 astroglial cells (C6 cells), primary cultured rat astrocytes, and normal human astrocytes. Amitriptyline-evoked GDNF mRNA expression and release were inhibited by pertussis toxin (PTX), a Gα(i/o) inhibitor, but not by NF449, a Gα(s) inhibitor, or YM-254890, a Gαq inhibitor. The activation of the GDNF production cascade (FGFR/FRS2α/ERK) was also inhibited by PTX. Deletion of Gα(ο1) and Gα(i3) by RNAi demonstrated that these G proteins play important roles in amitriptyline signaling. G protein activation was directly analyzed by electrical impedance-based biosensors (CellKey(TM) assay), using a label-free (without use of fluorescent proteins/probes or radioisotopes) and real time approach. Amitriptyline increased impedance, indicating Gα(i/o) activation that was suppressed by PTX treatment. The impedance evoked by amitriptyline was not affected by inhibitors of the GDNF production cascade. Furthermore, FGF2 treatment did not elicit any effect on impedance, indicating that amitriptyline targets PTX-sensitive Gα(i/o) upstream of the MMP/FGFR/FRS2α/ERK cascade. These results suggest novel targeting for the development of antidepressants. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Hypoacylated LPS from Foodborne Pathogen Campylobacter jejuni Induces Moderate TLR4-Mediated Inflammatory Response in Murine Macrophages

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Kirill V. Korneev

2018-02-01

Full Text Available Toll-like receptor 4 (TLR4 initiates immune response against Gram-negative bacteria upon specific recognition of lipid A moiety of lipopolysaccharide (LPS, the major component of their cell wall. Some natural differences between LPS variants in their ability to interact with TLR4 may lead to either insufficient activation that may not prevent bacterial growth, or excessive activation which may lead to septic shock. In this study we evaluated the biological activity of LPS isolated from pathogenic strain of Campylobacter jejuni, the most widespread bacterial cause of foodborne diarrhea in humans. With the help of hydrophobic chromatography and MALDI-TOF mass spectrometry we showed that LPS from a C. jejuni strain O2A consists of both hexaacyl and tetraacyl forms. Since such hypoacylation can result in a reduced immune response in humans, we assessed the activity of LPS from C. jejuni in mouse macrophages by measuring its capacity to activate TLR4-mediated proinflammatory cytokine and chemokine production, as well as NFκB-dependent reporter gene transcription. Our data support the hypothesis that LPS acylation correlates with its bioactivity.

Targeted delivery of TLR ligands to human and mouse dendritic cells strongly enhances adjuvanticity.

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Tacken, Paul J; Zeelenberg, Ingrid S; Cruz, Luis J; van Hout-Kuijer, Maaike A; van de Glind, Gerline; Fokkink, Remco G; Lambeck, Annechien J A; Figdor, Carl G

2011-12-22

Effective vaccines consist of 2 components: immunodominant antigens and effective adjuvants. Whereas it has been demonstrated that targeted delivery of antigens to dendritic cells (DCs) improves vaccine efficacy, we report here that co-targeting of TLR ligands (TLRLs) to DCs strongly enhances adjuvanticity and immunity. We encapsulated ligands for intracellular TLRs within biodegradable nanoparticles coated with Abs recognizing DC-specific receptors. Targeted delivery of TLRLs to human DCs enhanced the maturation and production of immune stimulatory cytokines and the Ag-specific activation of naive CD8(+) T cells. In vivo studies demonstrated that nanoparticles carrying Ag induced cytotoxic T-lymphocyte responses at 100-fold lower adjuvant dose when TLRLs were co-encapsulated instead of administered in soluble form. Moreover, the efficacy of these targeted TLRLs reduced the serum cytokine storm and related toxicity that is associated with administration of soluble TLRLs. We conclude that the targeted delivery of adjuvants may improve the efficacy and safety of DC-based vaccines.

Immunity to endotoxin and Asp299Gly polymorphism of TLR-4 in adult patients with early and late onset of asthma

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Yu. A. Bisyuk

2015-06-01

Full Text Available Aim. The gene polymorphism of Asp299Gly TLR-4 may be associated with the risk of asthma development. Methods and results. The gene polymorphism of TLR-4 (Asp299Gly receptor has been researched in 262 early-onset and in 69 late-onset asthma patients. The state of anti-endotoxin immunity was assessed by determination of specific antibodies to the endotoxin of A, M, G classes and sCD14 by ELISA. The polymorphism was analyzed by the allele-specific polymerase chain reaction with electrophoretic detection. It was estimated that the risk of early-onset asthma in the population of Crimea is associated with genotypes AG and GG (Asp299Gly of TLR-4. There were increased levels of anti-endotoxin IgM and decreased of sIgA in patients with late-onset asthma and AA genotype as compared to other genotypes. Conclusion. The gene polymorphism of Asp299Gly TLR-4 is associated with the risk of early-onset asthma development in Crimea population.

Dopamine antagonists for treatment resistance in autism spectrum disorders: review and focus on BDNF stimulators loxapine and amitriptyline.

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Hellings, Jessica A; Arnold, L Eugene; Han, Joan C

2017-04-01

Drug development and repurposing are urgently needed for individuals with autism spectrum disorders (ASD) and psychiatric comorbidity, which often presents as aggression and self-injury. Areas covered: We review dopamine antagonists, including classical and atypical, as well as unconventional antipsychotics in ASD. The older antipsychotic loxapine is discussed in terms of preliminary albeit limited evidence in ASD. Emerging promise of amitriptyline in ASD is discussed, together with promising BDNF effects of loxapine and amitriptyline. Expert opinion: In ASD, pharmacotherapy and specifically dopamine antagonist drugs are often prescribed for challenging behaviors including aggression. The novel antipsychotics risperidone and aripiprazole have received most study in ASD and are FDA-approved for irritability in children with ASD over age 5 years; individuals with ASD are prone to weight gain, Type II diabetes and associated side effects. Low dose loxapine has properties of classical and novel antipsychotics but importantly appears more weight neutral, and with promising use in adolescents and adults with ASD. Amitriptyline appears effective in ASD for irritability, aggression, gastrointestinal problems, and insomnia, in children, adolescents and adults however our adult data on amitriptyline in ASD is still in preparation for publication. Both loxapine and amitriptyline may stimulate BDNF; further studies are warranted.

The toll-like receptor 4 (TLR4) variant rs2149356 and risk of gout in European and polynesian sample sets

NARCIS (Netherlands)

Rasheed, Humaira; McKinney, Cushla; Stamp, Lisa K.; Dalbeth, Nicola; Topless, Ruth K.; Day, Richard; Kannangara, Diluk; Williams, Kenneth; Smith, Malcolm; Janssen, Matthijs; Jansen, Tim L.; Joosten, Leo A.; Radstake, Timothy R.; Riches, Philip L.; Tausche, Anne Kathrin; Lioté, Frederic; Lu, Leo; Stahl, Eli A.; Choi, Hyon K.; So, Alexander; Merriman, Tony R.

2016-01-01

Deposition of crystallized monosodium urate (MSU) in joints as a result of hyperuricemia is a central risk factor for gout. However other factors must exist that control the progression from hyperuricaemia to gout. A previous genetic association study has implicated the tolllike receptor 4 (TLR4)

Interactions of TLR4 and PPARγ, Dependent on AMPK Signalling Pathway Contribute to Anti-Inflammatory Effects of Vaccariae Hypaphorine in Endothelial Cells

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Haijian Sun

2017-07-01

Full Text Available Background /Aims: Accumulating evidence indicates that endothelial inflammation is one of the critical determinants in pathogenesis of atherosclerotic cardiovascular disease. Our previous studies had demonstrated that Vaccariae prevented high glucose or oxidative stress-triggered endothelial dysfunction in vitro. Very little is known about the potential effects of hypaphorine from Vaccariae seed on inflammatory response in endothelial cells. Methods: In the present study, we evaluated the anti-inflammatory effects of Vaccariae hypaphorine (VH on lipopolysaccharide (LPS-challenged endothelial EA.hy926 cells. The inflammatory cytokines including tumor necrosis factor-α (TNF-α, interleukin-1β (IL-1β, monocyte chemoattractant protein 1 (MCP-1 and vascular cellular adhesion molecule-1 (VCAM-1 were measured by real-time PCR (RT-PCR. The expressions of adenosine monophosphate-activated protein kinase (AMPK, acetyl-CoA carboxylase (ACC, toll-like receptor 4 (TLR4, peroxisome proliferator-activated receptor γ (PPARγ were detected by Western blotting or immunofluorescence. Results: We showed that LPS stimulated the expressions of TNF-α, IL-1β, MCP-1, VCAM-1 and TLR4, but attenuated the phosphorylation of AMPK and ACC as well as PPARγ protein levels, which were reversed by VH pretreatment. Moreover, we observed that LPS-upregulated TLR4 protein expressions were inhibited by PPARγ agonist pioglitazone, and the downregulated PPARγ expressions in response to LPS were partially restored by knockdown of TLR4. The negative regulation loop between TLR4 and PPARγ response to LPS was modulated by AMPK agonist AICAR (5-Aminoimidazole-4-carboxamide riboside or acadesine or A769662. Conclusions: Taken together, our results suggested that VH ameliorated LPS-induced inflammatory cytokines production in endothelial cells via inhibition of TLR4 and activation of PPARγ, dependent on AMPK signalling pathway.

Pharmacological TLR4 Inhibition Protects against Acute and Chronic Fat-Induced Insulin Resistance in Rats.

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Zhang, Ning; Liang, Hanyu; Farese, Robert V; Li, Ji; Musi, Nicolas; Hussey, Sophie E

2015-01-01

To evaluate whether pharmacological TLR4 inhibition protects against acute and chronic fat-induced insulin resistance in rats. For the acute experiment, rats received a TLR4 inhibitor [TAK-242 or E5564 (2x5 mg/kg i.v. bolus)] or vehicle, and an 8-h Intralipid (20%, 8.5 mg/kg/min) or saline infusion, followed by a two-step hyperinsulinemic-euglycemic clamp. For the chronic experiment, rats were subcutaneously implanted with a slow-release pellet of TAK-242 (1.5 mg/d) or placebo. Rats then received a high fat diet (HFD) or a low fat control diet (LFD) for 10 weeks, followed by a two-step insulin clamp. Acute experiment; the lipid-induced reduction (18%) in insulin-stimulated glucose disposal (Rd) was attenuated by TAK-242 and E5564 (the effect of E5564 was more robust), suggesting improved peripheral insulin action. Insulin was able to suppress hepatic glucose production (HGP) in saline- but not lipid-treated rats. TAK-242, but not E5564, partially restored this effect, suggesting improved HGP. Chronic experiment; insulin-stimulated Rd was reduced ~30% by the HFD, but completely restored by TAK-242. Insulin could not suppress HGP in rats fed a HFD and TAK-242 had no effect on HGP. Pharmacological TLR4 inhibition provides partial protection against acute and chronic fat-induced insulin resistance in vivo.

Morphine amplifies mechanical allodynia via TLR4 in a rat model of spinal cord injury

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Ellis, Amanda; Grace, Peter M.; Wieseler, Julie; Favret, Jacob; Springer, Kendra; Skarda, Bryce; Hutchinson, Mark R.; Falci, Scott; Rice, Kenner C.; Maier, Steven F.; Watkins, Linda R.

2016-01-01

Central neuropathic pain (CNP) is a pervasive, debilitating problem that impacts thousands of people living with central nervous system disorders, including spinal cord injury (SCI). Current therapies for treating this type of pain are ineffective and often have dose-limiting side effects. Although opioids are one of the most commonly used CNP treatments, recent animal literature has indicated that administering opioids shortly after a traumatic injury can actually have deleterious effects on long-term health and recovery. In order to study the deleterious effects of administering morphine shortly after trauma, we employed our low thoracic (T13) dorsal root avulsion model (Spinal Neuropathic Avulsion Pain, SNAP). Administering a weeklong course of 10 mg/kg/day morphine beginning 24 hr after SNAP resulted in amplified mechanical allodynia. Co-administering the non-opioid toll-like receptor 4 (TLR4) antagonist (+)-naltrexone throughout the morphine regimen prevented morphine-induced amplification of SNAP. Exploration of changes induced by early post-trauma morphine revealed that this elevated gene expression of TLR4, TNF, IL-1β, and NLRP3, as well as IL-1β protein at the site of spinal cord injury. These data suggest that a short course of morphine administered early after spinal trauma can exacerbate CNP in the long term. TLR4 initiates this phenomenon and, as such, may be potential therapeutic targets for preventing the deleterious effects of administering opioids after traumatic injury. PMID:27519154

TLR2-Modulating Lipoproteins of the Mycobacterium tuberculosis Complex Enhance the HIV Infectivity of CD4+ T Cells.

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Ciaran Skerry

Full Text Available Co-infection with Mycobacterium tuberculosis accelerates progression from HIV to AIDS. Our previous studies showed that M. tuberculosis complex, unlike M. smegmatis, enhances TLR2-dependent susceptibility of CD4+ T cells to HIV. The M. tuberculosis complex produces multiple TLR2-stimulating lipoproteins, which are absent in M. smegmatis. M. tuberculosis production of mature lipoproteins and TLR2 stimulation is dependent on cleavage by lipoprotein signal peptidase A (LspA. In order to determine the role of potential TLR2-stimulating lipoproteins on mycobacterial-mediated HIV infectivity of CD4+ T cells, we generated M. smegmatis recombinant strains overexpressing genes encoding various M. bovis BCG lipoproteins, as well as a Mycobacterium bovis BCG strain deficient in LspA (ΔlspA. Exposure of human peripheral blood mononuclear cells (PBMC to M. smegmatis strains overexpressing the BCG lipoproteins, LprF (p<0.01, LprH (p<0.05, LprI (p<0.05, LprP (p<0.001, LprQ (p<0.005, MPT83 (p<0.005, or PhoS1 (p<0.05, resulted in increased HIV infectivity of CD4+ T cells isolated from these PBMC. Conversely, infection of PBMC with ΔlspA reduced HIV infectivity of CD4+ T cells by 40% relative to BCG-infected cells (p<0.05. These results may have important implications for TB vaccination programs in areas with high mother-to-child HIV transmission.

TLR2-Modulating Lipoproteins of the Mycobacterium tuberculosis Complex Enhance the HIV Infectivity of CD4+ T Cells.

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Skerry, Ciaran; Klinkenberg, Lee G; Page, Kathleen R; Karakousis, Petros C

2016-01-01

Co-infection with Mycobacterium tuberculosis accelerates progression from HIV to AIDS. Our previous studies showed that M. tuberculosis complex, unlike M. smegmatis, enhances TLR2-dependent susceptibility of CD4+ T cells to HIV. The M. tuberculosis complex produces multiple TLR2-stimulating lipoproteins, which are absent in M. smegmatis. M. tuberculosis production of mature lipoproteins and TLR2 stimulation is dependent on cleavage by lipoprotein signal peptidase A (LspA). In order to determine the role of potential TLR2-stimulating lipoproteins on mycobacterial-mediated HIV infectivity of CD4+ T cells, we generated M. smegmatis recombinant strains overexpressing genes encoding various M. bovis BCG lipoproteins, as well as a Mycobacterium bovis BCG strain deficient in LspA (ΔlspA). Exposure of human peripheral blood mononuclear cells (PBMC) to M. smegmatis strains overexpressing the BCG lipoproteins, LprF (p<0.01), LprH (p<0.05), LprI (p<0.05), LprP (p<0.001), LprQ (p<0.005), MPT83 (p<0.005), or PhoS1 (p<0.05), resulted in increased HIV infectivity of CD4+ T cells isolated from these PBMC. Conversely, infection of PBMC with ΔlspA reduced HIV infectivity of CD4+ T cells by 40% relative to BCG-infected cells (p<0.05). These results may have important implications for TB vaccination programs in areas with high mother-to-child HIV transmission.

The effects of dexmedetomidine alone and in combination with tramadol or amitriptyline in a neuropathic pain model.

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Farghaly, Hanan Sm; Abd-Ellatief, Rasha B; Moftah, Marie Z; Mostafa, Mostafa G; Khedr, Eman M; Kotb, Hassan I

2014-01-01

Interactions between the sympathetic and somatic nervous system play an essential role in the pathophysiologic mechanisms of neuropathic pain. The α2-adrenoceptor agonists produce effective antinociception, but sedation is an important adverse effect. Multidrug therapy is potentially valuable to decrease side effects. The aim of the present study was to investigate the possible antinociceptive effect of dexmedetomidine, an α2-adrenoceptor agonist, and its combination with front-line treatment of neuropathic pain, i.e., amitriptyline or tramadol, in a chronic constriction injury (CCI) model of the sciatic nerve in rats. Controlled animal study. Following unilateral ligation of the left sciatic nerve, the effect of intraperitoneal (i.p.) dexmedetomidine (5 ug/kg), tramadol (5 mg/kg), and amitriptyline (30 mg/kg) on mechanical allodynia (measured by electrical von Frey apparatus) and hyperalgesia (measured by Randall and Selitto test) was studied. The sham-operated rats and un-operated hind paw (right paw) press normally on the floor reproduced by a weighted pain score of 0. Behavioral and mechanical tests confirmed the development of neuropathic pain after CCI. All individual drugs and dexmedetomidine combination with either tramadol or amitriptyline were effective in reducing mechanical allodynia and hyperalgesia. Dexmedetomidine, amitriptyline, tramadol, amitriptyline+dexmedetomidine, and tramadol+dexmedetomidine combination did not produce any sedation/motor impairment (P > 0.05). Although the combination of these drugs improved the CCI model of neuropathic pain in this study, an additional interpretation of the underlying mechanism(s) will be needed to confirm these findings. The combination of these drugs appears to be more effective in increasing the pain threshold after peripheral nerve injury, when compared with the administration of either of amitriptyline or tramadol alone and should be considered as a possible alternative to decrease side effects of

TLR4 accessory molecule RP105 (CD180 regulates monocyte-driven arteriogenesis in a murine hind limb ischemia model.

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Antonius J N M Bastiaansen

Full Text Available AIMS: We investigated the role of the TLR4-accessory molecule RP105 (CD180 in post-ischemic neovascularization, i.e. arteriogenesis and angiogenesis. TLR4-mediated activation of pro-inflammatory Ly6Chi monocytes is crucial for effective neovascularization. Immunohistochemical analyses revealed that RP105+ monocytes are present in the perivascular space of remodeling collateral arterioles. As RP105 inhibits TLR4 signaling, we hypothesized that RP105 deficiency would lead to an unrestrained TLR4-mediated inflammatory response and hence to enhanced blood flow recovery after ischemia. METHODS AND RESULTS: RP105-/- and wild type (WT mice were subjected to hind limb ischemia and blood flow recovery was followed by Laser Doppler Perfusion Imaging. Surprisingly, we found that blood flow recovery was severely impaired in RP105-/- mice. Immunohistochemistry showed that arteriogenesis was reduced in these mice compared to the WT. However, both in vivo and ex vivo analyses showed that circulatory pro-arteriogenic Ly6Chi monocytes were more readily activated in RP105-/- mice. FACS analyses showed that Ly6Chi monocytes became activated and migrated to the affected muscle tissues in WT mice following induction of hind limb ischemia. Although Ly6Chi monocytes were readily activated in RP105-/- mice, migration into the ischemic tissues was hampered and instead, Ly6Chi monocytes accumulated in their storage compartments, bone marrow and spleen, in RP105-/- mice. CONCLUSIONS: RP105 deficiency results in an unrestrained inflammatory response and monocyte over-activation, most likely due to the lack of TLR4 regulation. Inappropriate, premature systemic activation of pro-inflammatory Ly6Chi monocytes results in reduced infiltration of Ly6Chi monocytes in ischemic tissues and in impaired blood flow recovery.

TNF{alpha} and IL-1{beta} are mediated by both TLR4 and Nod1 pathways in the cultured HAPI cells stimulated by LPS

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Zheng, Wenwen; Zheng, Xuexing [College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, Jilin Province (China); Department of Anesthesiology, University of Miami Miller School of Medicine, Miami, FL 33136 (United States); Liu, Shue [Department of Anesthesiology, University of Miami Miller School of Medicine, Miami, FL 33136 (United States); Ouyang, Hongsheng [College of Animal Science and Veterinary Medicine, Jilin University, Changchun 130062, Jilin Province (China); Levitt, Roy C.; Candiotti, Keith A. [Department of Anesthesiology, University of Miami Miller School of Medicine, Miami, FL 33136 (United States); Hao, Shuanglin, E-mail: shao@med.miami.edu [Department of Anesthesiology, University of Miami Miller School of Medicine, Miami, FL 33136 (United States)

2012-04-20

Highlights: Black-Right-Pointing-Pointer LPS induces proinflammatory cytokine release in HAPI cells. Black-Right-Pointing-Pointer JNK pathway is dependent on TLR4 signaling to release cytokines. Black-Right-Pointing-Pointer NF-{kappa}B pathway is dependent on Nod1 signaling to release cytokines. -- Abstract: A growing body of evidence recently suggests that glial cell activation plays an important role in several neurodegenerative diseases and neuropathic pain. Microglia in the central nervous system express toll-like receptor 4 (TLR4) that is traditionally accepted as the primary receptor of lipopolysaccharide (LPS). LPS activates TLR4 signaling pathways to induce the production of proinflammatory molecules. In the present studies, we verified the LPS signaling pathways using cultured highly aggressively proliferating immortalized (HAPI) microglial cells. We found that HAPI cells treated with LPS upregulated the expression of TLR4, phospho-JNK (pJNK) and phospho-NF-{kappa}B (pNF-{kappa}B), TNF{alpha} and IL-1{beta}. Silencing TLR4 with siRNA reduced the expression of pJNK, TNF{alpha} and IL-1{beta}, but not pNF-{kappa}B in the cells. Inhibition of JNK with SP600125 (a JNK inhibitor) decreased the expression of TNF{alpha} and IL-1{beta}. Unexpectedly, we found that inhibition of Nod1 with ML130 significantly reduced the expression of pNF-{kappa}B. Inhibition of NF-{kappa}B also reduced the expression of TNF{alpha} and IL-1{beta}. Nod1 ligand, DAP induced the upregulation of pNF-{kappa}B which was blocked by Nod1 inhibitor. These data indicate that LPS-induced pJNK is TLR4-dependent, and that pNF-{kappa}B is Nod1-dependent in HAPI cells treated with LPS. Either TLR4-JNK or Nod1-NF-{kappa}B pathways is involved in the expression of TNF{alpha} and IL-1{beta}.

Bacterial endotoxin enhances colorectal cancer cell adhesion and invasion through TLR-4 and NF-kappaB-dependent activation of the urokinase plasminogen activator system.

LENUS (Irish Health Repository)

Killeen, S D

2009-05-19

Perioperative exposure to lipopolysaccharide (LPS) is associated with accelerated metastatic colorectal tumour growth. LPS directly affects cells through Toll-like receptor 4 (TLR-4) and the transcription factor NF-kappaB. The urokinase plasminogen activator (u-PA) system is intimately implicated in tumour cell extracellular matrix (ECM) interactions fundamental to tumour progression. Thus we sought to determine if LPS directly induces accelerated tumour cell ECM adhesion and invasion through activation of the u-PA system and to elucidate the cellular pathways involved. Human colorectal tumour cell lines were stimulated with LPS. u-PA concentration, u-PA activity, active u-PA, surface urokinase plasminogen activator receptor (u-PAR) and TLR-4 expression were assessed by ELISA, colorimetric assay, western blot analysis and flow cytometry respectively. In vitro tumour cell vitronectin adhesion and ECM invasion were analysed by vitronectin adhesion assay and ECM invasion chambers. u-PA and u-PAR function was inhibited with anti u-PA antibodies or the selective u-PA inhibitors amiloride or WXC-340, TLR-4 by TLR-4-blocking antibodies and NF-kappaB by the selective NF-kappaB inhibitor SN-50. LPS upregulates u-PA and u-PAR in a dose-dependent manner, enhancing in vitro tumour cell vitronectin adhesion and ECM invasion by >40% (P<0.01). These effects were ameliorated by u-PA and u-PAR inhibition. LPS activates NF-kappaB through TLR-4. TLR-4 and NF-kappaB inhibition ameliorated LPS-enhanced u-PA and u-PAR expression, tumour cell vitronectin adhesion and ECM invasion. LPS promotes tumour cell ECM adhesion and invasion through activation of the u-PA system in a TLR-4- and NF-kappaB-dependent manner.

The GABAA Receptor α2 Subunit Activates a Neuronal TLR4 Signal in the Ventral Tegmental Area that Regulates Alcohol and Nicotine Abuse

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Irina Balan

2018-04-01

Full Text Available Alcoholism initiates with episodes of excessive alcohol drinking, known as binge drinking, which is one form of excessive drinking (NIAAA Newsletter, 2004 that is related to impulsivity and anxiety (Ducci et al., 2007; Edenberg et al., 2004 and is also predictive of smoking status. The predisposition of non-alcohol exposed subjects to initiate binge drinking is controlled by neuroimmune signaling that includes an innately activated neuronal Toll-like receptor 4 (TLR4 signal. This signal also regulates cognitive impulsivity, a heritable trait that defines drug abuse initiation. However, the mechanism of signal activation, its function in dopaminergic (TH+ neurons within the reward circuitry implicated in drug-seeking behavior [viz. the ventral tegmental area (VTA], and its contribution to nicotine co-abuse are still poorly understood. We report that the γ-aminobutyric acidA receptor (GABAAR α2 subunit activates the TLR4 signal in neurons, culminating in the activation (phosphorylation/nuclear translocation of cyclic AMP response element binding (CREB but not NF-kB transcription factors and the upregulation of corticotropin-releasing factor (CRF and tyrosine hydroxylase (TH. The signal is activated through α2/TLR4 interaction, as evidenced by co-immunoprecipitation, and it is present in the VTA from drug-untreated alcohol-preferring P rats. VTA infusion of neurotropic herpes simplex virus (HSV vectors for α2 (pHSVsiLA2 or TLR4 (pHSVsiTLR4 but not scrambled (pHSVsiNC siRNA inhibits signal activation and both binge alcohol drinking and nicotine sensitization, suggesting that the α2-activated TLR4 signal contributes to the regulation of both alcohol and nicotine abuse.

Characterization of Toll-like receptors in primary lung epithelial cells: strong impact of the TLR3 ligand poly(I:C on the regulation of Toll-like receptors, adaptor proteins and inflammatory response

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Weith Andreas

2005-11-01

Full Text Available Abstract Background Bacterial and viral exacerbations play a crucial role in a variety of lung diseases including COPD or asthma. Since the lung epithelium is a major source of various inflammatory mediators that affect the immune response, we analyzed the inflammatory reaction of primary lung epithelial cells to different microbial molecules that are recognized by Toll-like receptors (TLR. Methods The effects of TLR ligands on primary small airway epithelial cells were analyzed in detail with respect to cytokine, chemokine and matrix metalloproteinase secretion. In addition, the regulation of the expression of TLRs and their adaptor proteins in small airway epithelial cells was investigated. Results Our data demonstrate that poly(I:C, a synthetic analog of viral dsRNA, mediated the strongest proinflammatory effects among the tested ligands, including an increased secretion of IL-6, IL-8, TNF-α, GM-CSF, GRO-α, TARC, MCP-1, MIP-3α, RANTES, IFN-β, IP-10 and ITAC as well as an increased release of MMP-1, MMP-8, MMP-9, MMP-10 and MMP-13. Furthermore, our data show that poly(I:C as well as type-1 and type-2 cytokines have a pronounced effect on the expression of TLRs and molecules involved in TLR signaling in small airway epithelial cells. Poly(I:C induced an elevated expression of TLR1, TLR2 and TLR3 and increased the gene expression of the general TLR adaptor MyD88 and IRAK-2. Simultaneously, poly(I:C decreased the expression of TLR5, TLR6 and TOLLIP. Conclusion Poly(I:C, an analog of viral dsRNA and a TLR3 ligand, triggers a strong inflammatory response in small airway epithelial cells that is likely to contribute to viral exacerbations of pulmonary diseases like asthma or COPD. The pronounced effects of poly(I:C on the expression of Toll-like receptors and molecules involved in TLR signaling is assumed to influence the immune response of the lung epithelium to viral and bacterial infections. Likewise, the regulation of TLR expression by type

Uncarinic Acid C Isolated from Uncaria rhynchophylla Induces Differentiation of Th1-Promoting Dendritic Cells Through TLR4 Signaling.

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Kim, Kyu Sik; Pham, Thanh Nhan Nguyen; Jin, Chun-Ji; Umeyama, Akemi; Shoji, Noboru; Hashimoto, Toshihiro; Lee, Je-Jung; Takei, Masao

2011-02-28

Uncarinic acid C (URC) is triterpene isolated from Uncaria rhynchophylla and is a pharmacologically active substance. The induction of dendritic cells (DC) is critical for the induction of Ag-specific T lymphocyte responses and may be essential for the development of human vaccines relying on T cell immunity. DC might be a potential target for URC. We demonstrate that URC activates human DC as documented by phenotypic and functional maturation, and altered cytokine production. The expression of CD1a, CD38, CD40, CD54, CD80, CD83, CD86, HLA-DR and CCR7 on URC-primed DC was enhanced. The production of IL-12p70 by URC-primed DC was higher than that of lipopolysaccharide (LPS)-primed DC. The production of IL-12p70 by URC-primed DC was inhibited by the anti-Toll-like receptor 4 (TLR4) monoclonal antibody (mAb), but partially abolished by anti-TLR2 mAb. mRNA coding for TLR2 and TLR4 was expressed in URC-primed DC. URC-primed DC induced the NF-κB transcription factor. Naïve T cells co-cultured with URC-primed DC turned into typical Th1 cells that produced large quantities of IFN-γ depending on IL-12 secretion. URC enhanced the T cell stimulatory capacity in an allo MLR. In the cytotoxic T-lymphocyte assay (CTL) assay, DNA fragmentation assay and (51)Cr release on URC-primed DC were more augmented than that of TNF-α-primed DC. DC matured with URC had an intermediate migratory capacity towards CCL19 and CCL21. These results suggest that URC modulates DC function in a fashion that favors Th1 polarization via the activation of IL-12p70 dependent on TLR4 signaling, and may be used on DC-based vaccine for cancer immunotherapy.

TLR-dependent control of Francisella tularensis infection and host inflammatory responses.

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Allison L Abplanalp

2009-11-01

Full Text Available Francisella tularensis is the causative agent of tularemia and is classified as a Category A select agent. Recent studies have implicated TLR2 as a critical element in the host protective response to F. tularensis infection, but questions remain about whether TLR2 signaling dominates the response in all circumstances and with all species of Francisella and whether F. tularensis PAMPs are predominantly recognized by TLR2/TLR1 or TLR2/TLR6. To address these questions, we have explored the role of Toll-like receptors (TLRs in the host response to infections with F. tularensis Live Vaccine Strain (LVS and F. tularensis subspecies (subsp. novicida in vivo.C57BL/6 (B6 control mice and TLR- or MyD88-deficient mice were infected intranasally (i.n. or intradermally (i.d. with F. tularensis LVS or with F. tularensis subsp. novicida. B6 mice survived >21 days following infection with LVS by both routes and survival of TLR1(-/-, TLR4(-/-, and TLR6(-/- mice infected i.n. with LVS was equivalent to controls. Survival of TLR2(-/- and MyD88(-/- mice, however, was significantly reduced compared to B6 mice, regardless of the route of infection or the subspecies of F. tularensis. TLR2(-/- and MyD88(-/- mice also showed increased bacterial burdens in lungs, liver, and spleen compared to controls following i.n. infection. Primary macrophages from MyD88(-/- and TLR2(-/- mice were significantly impaired in the ability to secrete TNF and other pro-inflammatory cytokines upon ex vivo infection with LVS. TNF expression was also impaired in vivo as demonstrated by analysis of bronchoalveolar lavage fluid and by in situ immunofluorescent staining.We conclude from these studies that TLR2 and MyD88, but not TLR4, play critical roles in the innate immune response to F. tularensis infection regardless of the route of infection or the subspecies. Moreover, signaling through TLR2 does not depend exclusively on TLR1 or TLR6 during F. tularensis LVS infection.

Stress-induced neuroinflammation is mediated by GSK3-dependent TLR4 signaling that promotes susceptibility to depression-like behavior.

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Cheng, Yuyan; Pardo, Marta; Armini, Rubia de Souza; Martinez, Ana; Mouhsine, Hadley; Zagury, Jean-Francois; Jope, Richard S; Beurel, Eleonore

2016-03-01

Most psychiatric and neurological diseases are exacerbated by stress. Because this may partially result from stress-induced inflammation, we examined factors involved in this stress response. After a paradigm of inescapable foot shock stress that causes learned helplessness depression-like behavior, eighteen cytokines and chemokines increased in mouse hippocampus, peaking 6-12h after stress. A 24h prior pre-conditioning stress accelerated the rate of stress-induced hippocampal cytokine and chemokine increases, with most reaching peak levels after 1-3h, often without altering the maximal levels. Toll-like receptor 4 (TLR4) was involved in this response because most stress-induced hippocampal cytokines and chemokines were attenuated in TLR4 knockout mice. Stress activated glycogen synthase kinase-3 (GSK3) in wild-type mouse hippocampus, but not in TLR4 knockout mice. Administration of the antidepressant fluoxetine or the GSK3 inhibitor TDZD-8 reduced the stress-induced increases of most hippocampal cytokines and chemokines. Stress increased hippocampal levels of the danger-associated molecular pattern (DAMP) protein high mobility group box 1 (HMGB1), activated the inflammatory transcription factor NF-κB, and the NLRP3 inflammasome. Knockdown of HMGB1 blocked the acceleration of cytokine and chemokine increases in the hippocampus caused by two successive stresses. Fluoxetine treatment blocked stress-induced up-regulation of HMGB1 and subsequent NF-κB activation, whereas TDZD-8 administration attenuated NF-κB activation downstream of HMGB1. To test if stress-induced cytokines and chemokines contribute to depression-like behavior, the learned helplessness model was assessed. Antagonism of TNFα modestly reduced susceptibility to learned helplessness induction, whereas TLR4 knockout mice were resistant to learned helplessness. Thus, stress-induces a broad inflammatory response in mouse hippocampus that involves TLR4, GSK3, and downstream inflammatory signaling, and

Stress-induced neuroinflammation is mediated by GSK3-dependent TLR4 signaling that promotes susceptibility to depression-like behavior

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Cheng, Yuyan; Pardo, Marta; de Souza Armini, Rubia; Martinez, Ana; Mouhsine, Hadley; Zagury, Jean-Francois; Jope, Richard S.; Beurel, Eleonore

2016-01-01

Most psychiatric and neurological diseases are exacerbated by stress. Because this may partially result from stress-induced inflammation, we examined factors involved in this stress response. After a paradigm of inescapable foot shock stress that causes learned helplessness depression-like behavior, eighteen cytokines and chemokines increased in mouse hippocampus, peaking 6 to 12 hr after stress. A 24 hr prior pre-conditioning stress accelerated the rate of stress-induced hippocampal cytokine and chemokine increases, with most reaching peak levels after 1 to 3 hr, often without altering the maximal levels. Toll-like receptor 4 (TLR4) was involved in this response because most stress-induced hippocampal cytokines and chemokines were attenuated in TLR4 knockout mice. Stress activated glycogen synthase kinase-3 (GSK3) in wild-type mouse hippocampus, but not in TLR4 knockout mice. Administration of the antidepressant fluoxetine or the GSK3 inhibitor TDZD-8 reduced the stress-induced increases of most hippocampal cytokines and chemokines. Stress increased hippocampal levels of the danger-associated molecular pattern (DAMP) protein high mobility group box 1 (HMGB1), activated the inflammatory transcription factor NF-κB, and the NLRP3 inflammasome. Knockdown of HMGB1 blocked the acceleration of cytokine and chemokine increases in the hippocampus caused by two successive stresses. Fluoxetine treatment blocked stress-induced up-regulation of HMGB1 and subsequent NF-κB activation, whereas TDZD-8 administration attenuated NF-κB activation downstream of HMGB1. To test if stress-induced cytokines and chemokines contribute to depression-like behavior, the learned helplessness model was assessed. Antagonism of TNFα modestly reduced susceptibility to learned helplessness induction, whereas TLR4 knockout mice were resistant to learned helplessness. Thus, stress-induces a broad inflammatory response in mouse hippocampus that involves TLR4, GSK3, and downstream inflammatory

TLR9 played a more important role than TLR2 in the combination of maltose-binding protein and BCG-induced Th1 activation.

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Ni, Weihua; Wang, Fang; Liu, Guomu; Zhang, Nannan; Yuan, Hongyan; Jie, Jing; Tai, Guixiang

2016-11-01

Our previous study demonstrated that maltose-binding protein (MBP) combined with BCG induced synergistic mouse Th1 activation in vivo. Here, to explore the mechanism of MBP combined with BCG on Th1 activation, mouse purified CD4 + T cells were stimulated with MBP and BCG in vitro. The results showed that MBP combined with BCG synergistically increased IFN-γ production, accompanied with the upregulation of TLR2/9 expressions, suggesting that TLR2/9 were involved in the combination-induced Th1 activation. Next, TLR2 antibodies and TLR9 inhibitor were used to further analyze the effects of TLRs in Th1 activation. Results showed TLR2 antibody partly decreased MBP combined with BCG-induced IFN-γ production, MyD88 expression and IκB phosphorylation, indicating that TLR2-mediated MyD88-dependent pathway was involved in the MBP combined with BCG-induced Th1 activation. Moreover, MBP combined with BCG-induced Th1 activation was completely abrogated by TLR9 inhibitor, suggesting that TLR9-mediated MyD88-dependent pathway played a more important role than TLR2 in the combination-induced Th1 activation. Further study showed that TLR9 inhibitor downregulated TLR2 expression, suggesting that TLR9 signaling regulated TLR2 activation to favor Th1 resonse induced by MBP combined with BCG. Collectively, we demonstrated for the first time that the cross-talk of TLR2 and TLR9 triggered Th1 activation collaboratively and our findings provided valuable information about designing more effective adjuvant for cancer therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Wogonin improves histological and functional outcomes, and reduces activation of TLR4/NF-κB signaling after experimental traumatic brain injury.

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Chien-Cheng Chen

Full Text Available Traumatic brain injury (TBI initiates a neuroinflammatory cascade that contributes to neuronal damage and behavioral impairment. This study was undertaken to investigate the effects of wogonin, a flavonoid with potent anti-inflammatory properties, on functional and histological outcomes, brain edema, and toll-like receptor 4 (TLR4- and nuclear factor kappa B (NF-κB-related signaling pathways in mice following TBI.Mice subjected to controlled cortical impact injury were injected with wogonin (20, 40, or 50 mg·kg(-1 or vehicle 10 min after injury. Behavioral studies, histology analysis, and measurement of blood-brain barrier (BBB permeability and brain water content were carried out to assess the effects of wogonin. Levels of TLR4/NF-κB-related inflammatory mediators were also examined. Treatment with 40 mg·kg(-1 wogonin significantly improved functional recovery and reduced contusion volumes up to post-injury day 28. Wogonin also significantly reduced neuronal death, BBB permeability, and brain edema beginning at day 1. These changes were associated with a marked reduction in leukocyte infiltration, microglial activation, TLR4 expression, NF-κB translocation to nucleus and its DNA binding activity, matrix metalloproteinase-9 activity, and expression of inflammatory mediators, including interleukin-1β, interleukin-6, macrophage inflammatory protein-2, and cyclooxygenase-2.Our results show that post-injury wogonin treatment improved long-term functional and histological outcomes, reduced brain edema, and attenuated the TLR4/NF-κB-mediated inflammatory response in mouse TBI. The neuroprotective effects of wogonin may be related to modulation of the TLR4/NF-κB signaling pathway.

MAPK/p38 regulation of cytoskeleton rearrangement accelerates induction of macrophage activation by TLR4, but not TLR3.

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Bian, Hongjun; Li, Feifei; Wang, Wenwen; Zhao, Qi; Gao, Shanshan; Ma, Jincai; Li, Xiao; Ren, Wanhua; Qin, Chengyong; Qi, Jianni

2017-11-01

Toll-like receptor 3 (TLR3) and TLR4 utilize adaptor proteins to activate mitogen‑activated protein kinase (MAPK), resulting in the acute but transient inflammatory response aimed at the clearance of pathogens. In the present study, it was demonstrated that macrophage activation by lipopolysaccharide (LPS) or poly(I:C), leading to changes in cell morphology, differed significantly between the mouse macrophage cell line RAW264.7 and mouse primary peritoneal macrophages. Moreover, the expression of α- and β-tubulin was markedly decreased following LPS stimulation. By contrast, α- and β-tubulin expression were only mildly increased following poly(I:C) treatment. However, the expression of β-actin and GAPDH was not significantly affected. Furthermore, it was verified that vincristine pretreatment abrogated the cytoskeleton rearrangement and decreased the synthesis and secretion of proinflammatory cytokines and migration of macrophages caused by LPS. Finally, it was observed that the MAPK/p38 signaling pathway regulating cytoskeleton rearrangement may participate in LPS‑induced macrophage cytokine production and migration. Overall, the findings of the present study indicated that MAPK/p38 regulation of the cytoskeleton, particularly tubulin proteins, plays an important role in LPS-induced inflammatory responses via alleviating the synthesis and secretion of proinflammatory cytokines and inhibiting the migration of macrophages.

Association of gene variants in TLR4 and IL-6 genes with Perthes disease

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Srzentić Sanja

2014-01-01

Full Text Available Introduction. Perthes disease is idiopathic avascular osteonecrosis of the hip in children, with unknown etiology. Inflammation is present during development of Perthes disease and it is known that this process influences bone remodeling. Objective. Since genetic studies related to inflammation have not been performed in Perthes disease so far, the aim of this study was to analyze the association of frequencies of genetic variants of immune response genes, toll-like receptor 4 (TLR4 and interleukin-6 (IL-6, with this disease. Methods. The study cohort consisted of 37 patients with Perthes disease and 50 healthy controls. Polymorphisms of well described inflammatory mediators: TLR4 (Asp299Gly, Thr399Ile and IL-6 (G-174C, G- 597A were determined by polymerase chain reaction restriction fragment length polymorphism method. Results. IL-6 G-174C and G-597A polymorphisms were in complete linkage disequilibrium. A statistically significant increase of heterozygote subjects for IL-6 G-174C/G-597A was found in controls in comparison to Perthes patient group (p=0.047, OR=2.49, 95% CI=1.00-6.21. Also, the patient group for IL-6 G-174C/G- 597A polymorphisms was not in Hardy-Weinberg equilibrium. No statistically significant differences were found between patient and control groups for TLR4 analyzed polymorphisms. A stratified analysis by the age at disease onset also did not reveal any significant difference for all analyzed polymorphisms. Conclusion. Our study revealed that heterozygote subjects for the IL-6 G-174C/G-597A polymorphisms were significantly overrepresented in the control group than in the Perthes patient group. Consequently, we concluded that children who are heterozygous for these polymorphisms have a lower chance of developing Perthes disease than carriers of both homozygote genotypes. [Projekat Ministarstva nauke Republike Srbije, br. III41004

[Gallic acid inhibits inflammatory response of RAW264.7 macrophages by blocking the activation of TLR4/NF-κB induced by LPS].

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Huang, Lihua; Hou, Lin; Xue, Hainan; Wang, Chunjie

2016-12-01

Objective To observe the influence of gallic acid on Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway in the RAW264.7 macrophages stimulated by lipopolysaccharide (LPS). Methods RAW264.7 macrophages were divided into the following groups: control group, LPS group, LPS combined with gallic acid group, LPS combined with pyrrolidine dithiocarbamate (PDTC) group and LPS combined with dexamethasone (DM) group. RAW264.7 cells were cultured for 24 hours after corresponding treatments. The levels of tumor necrosis factor α (TNF-α), interleukin-1 (IL-1) and IL-6 were detected by ELISA. The levels of TLR4 and NF-κB mRNAs were tested by real-time PCR. The levels of p-IκBα, p65, p-p65 and TLR4 proteins were examined by Western blotting. Results The expression levels of TNF-α, IL-1 and IL-6 were up-regulated in the RAW264.7 macrophages after stimulated by LPS. Gallic acid could reduce the elevated expression levels of TNF-α, IL-1 and IL-6 induced by LPS. The expression of TLR4 significantly increased after stimulated by LPS and NF-κB was activated. Gallic acid could reverse the above changes and prevent the activation of NF-κB. Conclusion Gallic acid could inhibit LPS-induced inflammatory response in RAW264.7 macrophages via TLR4/NF-κB pathway.

Hyperin protects against LPS-induced acute kidney injury by inhibiting TLR4 and NLRP3 signaling pathways

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Chunzhi, Gong; Zunfeng, Li; Chengwei, Qin; Xiangmei, Bu; Jingui, Yu

2016-01-01

Hyperin is a flavonoid compound derived from Ericaceae, Guttifera, and Celastraceae that has been shown to have various biological effects, such as anti-inflammatory and anti-oxidant effects. However, there is no evidence to show the protective effects of hyperin on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). Therefore, we investigated the protective effects and mechanism of hyperin on LPS-induced AKI in mice. The levels of TNF-α, IL-6, and IL-1β were tested by ELISA. The effects of hyperin on blood urea nitrogen (BUN) and serum creatinine were also detected. In addition, the expression of TLR4, NF-κB, and NLRP3 were detected by western blot analysis. The results showed that hyperin significantly inhibited LPS-induced TNF-α, IL-6, and IL-1β production. The levels of BUN and creatinine were also suppressed by hyperin. Furthermore, LPS-induced TLR4 expression and NF-κB activation were also inhibited by hyperin. In addition, treatment of hyperin dose-dependently inhibited LPS-induced NLRP3 signaling pathway. In conclusion, the results showed that hyperin inhibited LPS-induced inflammatory response by inhibiting TLR4 and NLRP3 signaling pathways. Hyperin has potential application prospects in the treatment of sepsis-induced AKI. PMID:27813491

Pretreatment of Sialic Acid Efficiently Prevents Lipopolysaccharide-Induced Acute Renal Failure and Suppresses TLR4/gp91-Mediated Apoptotic Signaling

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Shih-Ping Hsu

2016-05-01

Full Text Available Background/Aims: Lipopolysaccharides (LPS binding to Toll-like receptor 4 (TLR4 activate NADPH oxidase gp91 subunit-mediated inflammation and oxidative damage. Recognizing the high binding affinity of sialic acid (SA with LPS, we further explored the preventive potential of SA pretreatment on LPS-evoked acute renal failure (ARF. Methods: We determined the effect of intravenous SA 30 min before LPS-induced injury in urethane-anesthetized female Wistar rats by evaluating kidney reactive oxygen species (ROS responses, renal and systemic hemodynamics, renal function, histopathology, and molecular mechanisms. Results: LPS time-dependently reduced arterial blood pressure, renal microcirculation, and increased blood urea nitrogen and creatinine in the rats. LPS enhanced monocyte/macrophage infiltration and ROS production, and subsequently impaired kidneys with the enhancement of TLR4/NADPH oxidase gp91/Caspase 3/poly-(ADP-ribose-polymerase (PARP-mediated apoptosis in the kidneys. SA pretreatment effectively alleviated LPS-induced ARF. The levels of LPS-increased ED-1 infiltration and ROS production in the kidney were significantly depressed by SA pretreatment. Furthermore, SA pretreatment significantly depressed TLR4 activation, gp91 expression, and Caspase 3/PARP induced apoptosis in the kidneys. Conclusion: We suggest that pretreatment of SA significantly and preventively attenuated LPS-induced detrimental effects on systemic and renal hemodynamics, renal ROS production and renal function, as well as, LPS-activated TLR4/gp91/Caspase3 mediated apoptosis signaling.

TLR9 is required for MAPK/NF-κB activation but does not cooperate with TLR2 or TLR6 to induce host resistance to Brucella abortus.

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Gomes, Marco Túlio; Campos, Priscila Carneiro; Pereira, Guilherme de Sousa; Bartholomeu, Daniella Castanheira; Splitter, Gary; Oliveira, Sergio Costa

2016-05-01

Brucella abortus is a Gram-negative intracellular bacterial pathogen that causes a zoonosis of worldwide occurrence, leading to undulant fever in humans and abortion in domestic animals. B. abortus is recognized by several pattern-recognition receptors triggering pathways during the host innate immune response. Therefore, here, we determined the cooperative role of TLR9 with TLR2 or TLR6 receptors in sensing Brucella Furthermore, we deciphered the host innate immune response against B. abortus or its DNA, emphasizing the role of TLR9-MAPK/NF-κB signaling pathways in the production of proinflammatory cytokines. TLR9 is required for the initial host control of B. abortus, but this TLR was dispensable after 6 wk of infection. The susceptibility of TLR9(-/-)-infected animals to Brucella paralleled with lower levels of IFN-γ produced by mouse splenocytes stimulated with this pathogen compared with wild-type cells. However, no apparent cooperative interplay was observed between TLR2-TLR9 or TLR6-TLR9 receptors to control infection. Moreover, B. abortus or its DNA induced activation of MAPK/NF-κB pathways and production of IL-12 and TNF-α by macrophages partially dependent on TLR9 but completely dependent on MyD88. In addition, B. abortus-derived CpG oligonucleotides required TLR9 to promote IL-12 and TNF-α production by macrophages. By confocal microscopy, we demonstrated that TLR9 redistributed and colocalized with lysosomal-associated membrane protein-1 upon Brucella infection. Thus, B. abortus induced TLR9 traffic, leading to cell signaling activation and IL-12 and TNF-α production. Although TLR9 recognized Brucella CpG motifs, our results suggest a new pathway of B. abortus DNA-activating macrophages independent of TLR9. © Society for Leukocyte Biology.

MicroRNA-129-5p inhibits the development of autoimmune encephalomyelitis-related epilepsy by targeting HMGB1 through the TLR4/NF-kB signaling pathway.

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Liu, Ai-Hua; Wu, Ya-Ting; Wang, Yu-Ping

2017-06-01

The study aimed to explore the effects of microRNA-129-5p (miR-129-5p) on the development of autoimmune encephalomyelitis (AE)-related epilepsy by targeting HMGB1 through the TLR4/NF-kB signaling pathway in a rat model. AE-related epilepsy models were established. Sprague-Dawley (SD) rats were randomly divided into control, model, miR-129-5p mimics, miR-129-5p inhibitor, HMGB1 shRNA, TLR4/NF-kB (TLR4/NF-kB signaling pathway was inhibited) and miR-129-5p mimics+HMGB1 shRNA groups respectively. Latency to a first epilepsy seizure attack was recorded. Neuronal injuries in the hippocampus regions were detected using HE, Nissl and FJB staining methods 24h following model establishment. Microglial cells were detected by OX-42 immunohistochemistry. Expressions of miR-129-5p, HMGB1 and TLR4/NF-kB signaling pathway-related proteins were detected by qRT-PCR. Protein expressions of HMGB1 and TLR4/NF-kB signaling pathway-related proteins were detected by Western blotting. Dual luciferase reporter gene assay showed that miR-129-5p was negatively targeting HMGB1. Neurons of hippocampal tissues in rats were heavily injured by an injection of lithium chloride. Compared with the model and control groups, neuronal injury of the hippocampus and AE-related epilepsy decreased and microglial cells increased in the miR-129-5p mimics, HMGB1 shRNA and TLR4/NF-kB groups; however, in the miR-129-5p inhibitor group, miR-129-5p expression decreased, HMGB1 expression increased, TLR4/NF-kB signaling pathway was activated, latency to a first epilepsy seizure attack was shortened, and neuronal injury increased. This study provides evidence that miR-129-5p inhibits the development of AE-related epilepsy by suppressing HMGB1 expression and inhibiting TLR4/NF-kB signaling pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

Unilateral Partial Nephrectomy with Warm Ischemia Results in Acute Hypoxia Inducible Factor 1-Alpha (HIF-1α and Toll-Like Receptor 4 (TLR4 Overexpression in a Porcine Model.

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Zhiyong Zhang

Full Text Available Ischemia/reperfusion (I/R during partial nephrectomy (PN contributes to acute kidney injury (AKI, which is inaccurately assessed using existent clinical markers of renal function. We evaluated I/R-related changes in expression in hypoxia inducible factor 1α (HIF-1α and toll-like receptor 4 (TLR4, within kidney tissue and peripheral blood leukocytes (PBL in a porcine model of PN.Three adult pigs each underwent unilateral renal hilar cross clamping for 180 min followed by a 15 min reperfusion. The contralateral kidney served as control. Biopsies of clamped kidneys were obtained at baseline (time 0, every 60 min during the hypoxic phase, and post-reperfusion. Control kidneys were biopsied once at 180 min. Peripheral blood was sampled at time 0, every 30 min during the hypoxic phase, and post-reperfusion. HIF-1α and TLR4 expression in kidney tissue and PBL were analyzed by Western blotting. I/R-related histological changes were assessed.Expression of HIF-1α in clamped kidneys and PBL was below detection level at baseline, rising to detectable levels after 60 min of hypoxia, and continuing to rise throughout the hypoxic and reperfusion phases. Expression of TLR-4 in clamped kidneys followed a similar trend with initial detection after 30-60 min of hypoxia. Control kidneys exhibited no change in HIF-1α or TLR-4 expression. I/R-related histologic changes were minimal, primarily mild tubular dilatation.In a porcine model of PN, HIF-1α and TLR4 exhibited robust, I/R-related increases in expression in kidney tissue and PBL. Further studies investigating these molecules as potential markers of AKI are warranted.

A preliminary study on the association of single nucleotide polymorphisms of interleukin 4 (IL4, IL13, IL4 receptor alpha (IL4Rα & Toll-like receptor 4 (TLR4 genes with asthma in Indian adults

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Parisa Davoodi

2015-01-01

Full Text Available Background & objectives: Interleukin 4 (IL4 and IL13 genes are believed to be responsible for inflammation of the airways in asthmatics. These share a common receptor component called IL4Rα which is another potentially important candidate gene linked to asthma phenotypes. Another gene Toll-like receptor 4 (TLR4 might affect the incidence or progression of asthma through the expression of proinflammatory genes. Several single nucleotide polymorphisms (SNPs in IL4, IL13, IL4Rα and TLR4 have been reported to be linked to asthma or related phenotypes in several ethnic populations using linkage studies and association studies. However, the results have not been consistent. We investigated five SNPs (C-589T and C-33T of IL4, G+2044A of IL13, A+1902G of IL4Rα, and A+896G of TLR4 in patients with adult onset asthma to evaluate their role in manifestation and severity of asthma. Methods: Adult (>18 yr of age patients with asthma (n=100 and healthy controls (n=50 were included in the study. Genotyping was performed using sequenom MassARRAY technology. Results: The mutant alleles of the C-589T and C-33T SNPs in the promoter region of IL4 were present in 4 per cent patients with asthma but absent from the control group suggesting that the variations in IL4 may contribute to asthma occurrence. The SNPs of other genes were seen in both controls and patients. Interpretation & conclusions: The results suggest the possible association between the genetic distribution of C-589T and C-33T SNPs of IL4 with asthma in Indian adults.

The Probiotic Lactobacillus Prevents Citrobacter rodentium-Induced Murine Colitis in a TLR2-Dependent Manner.

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Ryu, Seung-Hyun; Park, Jong-Hyung; Choi, Soo-Young; Jeon, Hee-Yeon; Park, Jin-Il; Kim, Jun-Young; Ham, Seung-Hoon; Choi, Yang-Kyu

2016-07-28

The main objective of this study was to investigate whether Lactobacillus rhamnosus GG (LGG) ameliorated the effects of Citrobactor rodentium infection in Toll-like receptor 2 (TLR2) knockout (KO) and TLR4 KO mice, as well as in wild-type C57BL/6 (B6) mice. TLR2 KO, TLR4 KO, and B6 mice were divided into three groups per each strain. Each group had an uninfected control group (n = 5), C. rodentium-infected group (n = 8), and LGG-pretreated C. rodentium-infected group (n = 8). The survival rate of B6 mice infected with C. rodentium was higher when pretreated with LGG. Pretreatment with LGG ameliorated C. rodentium-induced mucosal hyperplasia in B6 and TLR4 KO mice. However, in C-rodentium-infected TLR2 KO mice, mucosal hyperplasia persisted, regardless of pretreatment with LGG. In addition, LGG-pretreated B6 and TLR4 KO mice showed a decrease in spleen weight and downregulation of tumor necrosis factor alpha, interferon gamma, and monocyte chemotactic protein 1 mRNA expression compared with the non-pretreated group. In contrast, such changes were not observed in TLR2 KO mice, regardless of pretreatment with LGG. From the above results, we conclude that pretreatment with LGG ameliorates C. rodentium-induced colitis in B6 and TLR4 KO mice, but not in TLR2 KO mice. Therefore, LGG protects mice from C. rodentium-induced colitis in a TLR2-dependent manner.

Analysis of TLR polymorphisms in typhoid patients and ...

African Journals Online (AJOL)

Ilakkia Sivaji

2016-01-20

Jan 20, 2016 ... implicated the genetic variations (polymorphisms) in TLR genes to influence the host susceptibility to infectious diseases. However, the available literature on TLR polymorphism and susceptibility to typhoid fever is unclear. Aim: This study aimed to investigate the polymorphism of TLRs 1, 2, 4 and 5 in ...

Lipopolysaccharide promotes lipid accumulation in human adventitial fibroblasts via TLR4-NF-κB pathway

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Wang Jun

2012-10-01

Full Text Available Abstract Background Atherosclerosis is a chronic degenerative disease of the arteries and is thought to be one of the most common causes of death globally. In recent years, the functions of adventitial fibroblasts in the development of atherosclerosis and tissue repair have gained increased interests. LPS can increase the morbidity and mortality of atherosclerosis-associated cardiovascular disease. Although LPS increases neointimal via TLR4 activation has been reported, how LPS augments atherogenesis through acting on adventitial fibroblasts is still unknown. Here we explored lipid deposition within adventitial fibroblasts mediated by lipopolysaccharide (LPS to imitate inflammatory conditions. Results In our study, LPS enhanced lipid deposition by the up-regulated expression of adipose differentiation-related protein (ADRP as the silencing of ADRP abrogated lipid deposition in LPS-activated adventitial fibroblasts. In addition, pre-treatment with anti-Toll-like receptor 4 (TLR4 antibody diminished the LPS-induced lipid deposition and ADRP expression. Moreover, LPS induced translocation of nuclear factor-κB (NF-κB, which could markedly up-regulate lipid deposition as pre-treatment with the NF-κB inhibitor, PDTC, significantly reduced lipid droplets. In addition, the lowering lipid accumulation was accompanied with the decreased ADRP expression. Furthermore, LPS-induced adventitial fibroblasts secreted more monocyte chemoattractant protein (MCP-1, compared with transforming growth factor-β1 (TGF-β1. Conclusions Taken together, these results suggest that LPS promotes lipid accumulation via the up-regulation of ADRP expression through TLR4 activated downstream of NF-κB in adventitial fibroblasts. Increased levels of MCP-1 released from LPS-activated adventitial fibroblasts and lipid accumulation may accelerate monocytes recruitment and lipid-laden macrophage foam cells formation. Here, our study provides a new explanation as to how bacterial

Lipopolysaccharide promotes lipid accumulation in human adventitial fibroblasts via TLR4-NF-κB pathway.

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Wang, Jun; Si, Yanfang; Wu, Chen; Sun, Lu; Ma, Yudong; Ge, Aili; Li, Baomin

2012-10-17

Atherosclerosis is a chronic degenerative disease of the arteries and is thought to be one of the most common causes of death globally. In recent years, the functions of adventitial fibroblasts in the development of atherosclerosis and tissue repair have gained increased interests. LPS can increase the morbidity and mortality of atherosclerosis-associated cardiovascular disease. Although LPS increases neointimal via TLR4 activation has been reported, how LPS augments atherogenesis through acting on adventitial fibroblasts is still unknown. Here we explored lipid deposition within adventitial fibroblasts mediated by lipopolysaccharide (LPS) to imitate inflammatory conditions. In our study, LPS enhanced lipid deposition by the up-regulated expression of adipose differentiation-related protein (ADRP) as the silencing of ADRP abrogated lipid deposition in LPS-activated adventitial fibroblasts. In addition, pre-treatment with anti-Toll-like receptor 4 (TLR4) antibody diminished the LPS-induced lipid deposition and ADRP expression. Moreover, LPS induced translocation of nuclear factor-κB (NF-κB), which could markedly up-regulate lipid deposition as pre-treatment with the NF-κB inhibitor, PDTC, significantly reduced lipid droplets. In addition, the lowering lipid accumulation was accompanied with the decreased ADRP expression. Furthermore, LPS-induced adventitial fibroblasts secreted more monocyte chemoattractant protein (MCP-1), compared with transforming growth factor-β1 (TGF-β1). Taken together, these results suggest that LPS promotes lipid accumulation via the up-regulation of ADRP expression through TLR4 activated downstream of NF-κB in adventitial fibroblasts. Increased levels of MCP-1 released from LPS-activated adventitial fibroblasts and lipid accumulation may accelerate monocytes recruitment and lipid-laden macrophage foam cells formation. Here, our study provides a new explanation as to how bacterial infection contributes to the pathological process of

Procyanidin dimer B2-mediated IRAK-M induction negatively regulates TLR4 signaling in macrophages

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Sung, Nak-Yun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Yang, Mi-So [Department of Microbiology, Infection Signaling Network Research Center, College of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Song, Du-Sub [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); School of life sciences and Biotechnology, Korea University 5-ka, Anam-Dong, Sungbuk-ku, Seoul 136-701 (Korea, Republic of); Kim, Jae-Kyung; Park, Jong-Heum; Song, Beom-Seok; Park, Sang-Hyun; Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Hyun-Jin [School of life sciences and Biotechnology, Korea University 5-ka, Anam-Dong, Sungbuk-ku, Seoul 136-701 (Korea, Republic of); Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Byun, Eui-Baek, E-mail: ebbyun80@kaeri.re.kr [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Byun, Eui-Hong, E-mail: ehbyun80@kongju.ac.k [Department of Food Science and Technology, Kongju National University, Yesan 340-800 (Korea, Republic of)

2013-08-16

Highlights: •Pro B2 elevated the expression of IRAK-M, a negative regulator of TLR signaling. •LPS-induced expression of cell surface molecules was inhibited by Pro B2. •LPS-induced production of pro-inflammatory cytokines was inhibited by Pro B2. •Pro B2 inhibited LPS-induced activation of MAPKs and NF-κB through IRAK-M. •Pro B2 inactivated naïve T cells by inhibiting LPS-induced cytokines via IRAK-M. -- Abstract: Polyphenolic compounds have been found to possess a wide range of physiological activities that may contribute to their beneficial effects against inflammation-related diseases; however, the molecular mechanisms underlying this anti-inflammatory activity are not completely characterized, and many features remain to be elucidated. In this study, we investigated the molecular basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by procyanidin dimer B2 (Pro B2) in macrophages. Pro B2 markedly elevated the expression of the interleukin (IL)-1 receptor-associated kinase (IRAK)-M protein, a negative regulator of TLR signaling. Lipopolysaccharide (LPS)-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II) and production of pro-inflammatory cytokines (tumor necrosis factor-α, IL-1β, IL-6, and IL-12p70) were inhibited by Pro B2, and this action was prevented by IRAK-M silencing. In addition, Pro B2-treated macrophages inhibited LPS-induced activation of mitogen-activated protein kinases such as extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase and the translocation of nuclear factor κB and p65 through IRAK-M. We also found that Pro B2-treated macrophages inactivated naïve T cells by inhibiting LPS-induced interferon-γ and IL-2 secretion through IRAK-M. These novel findings provide new insights into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and the immune-pharmacological role of Pro B2 in the immune response against the development

[Fisetin alleviates hypoxia/reoxygenation injury in rat hepatocytes via modulation of TLR4/NF-κB signaling pathway].

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Pu, Junliang; Wan, Lei; Zheng, Daofeng; Wei, Xufu; Wu, Zhongjun; Tang, Chengyong

2017-07-01

Objective To investigate the protective effect of fisetin (FIS) against hypoxia/reoxygenation (H/R) injury in rat hepatocytes and its mechanism. Methods H/R injury model of BRL-3A cells was established and the cells were pretreated with FIS. Survival rate was detected by CCK-8 assay. Cell apoptosis was measured by flow cytometry. The levels of ALT and AST were determined by microplate assay. The production of TNF-α and IL-1β were detected by ELISA. The mRNA and protein levels of TLR4 and NF-κBp65 were analyzed by quantitative real-time PCR and Western blotting, respectively. Results After subjected to H/R, cell survival rate decreased and the apoptosis level increased. The levels of ALT and AST in cell supernatant were elevated, so were the production of TNF-α and IL-1β. FIS pretreatment increased the cell survival rate and inhibited apoptosis. The levels of ALT, AST and the production of TNF-α and IL-1β were reduced significantly. Moreover, FIS inhibited the increasing expression levels of TLR4 and NF-κBp65 induced by H/R. Conclusion FIS alleviates the hepatocyte injury induced by H/R via modulation of TLR4/NF-κB signaling pathway.

Polymorphisms in NFKB1 and TLR4 and interaction with dietary and life style factors in relation to colorectal cancer in a Danish prospective case-cohort study.

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Kopp, Tine Iskov; Andersen, Vibeke; Tjonneland, Anne; Vogel, Ulla

2015-01-01

Maintenance of a balance between commensal bacteria and the mucosal immune system is crucial and intestinal dysbiosis may be a key event in the pathogenesis of colorectal cancer (CRC). The toll-like receptor 4 (TLR4) is an important pattern-recognition receptor that regulates inflammation and barrier function in the gut by a mechanism that involves activation of the nuclear factor-κB (NF-κB) transcription factor. Dietary and life style factors may impact these functions. We therefore used a Danish prospective case-cohort study of 1010 CRC cases and 1829 randomly selected participants from the Danish Diet, Cancer and Health cohort to investigate three polymorphisms in NFKB1 and TLR4 and their possible interactions with diet and life style factors in relation to risk of CRC. Homozygous carriage of the variant allele of the TLR4/rs5030728 polymorphism was associated with increased risk of CRC (incidence rate ratio (IRR) = 1.30; 95% confidence interval (CI): 1.05-1.60; P = 0.02 (gene-dose model); IRR = 1.24; 95%CI: 1.01-1.51; P = 0.04 (recessive model)). Del-carriers of the NFKB1/rs28362491 polymorphism had a 17% (95%CI: 1.03-1.34; P = 0.02) increased risk of CRC compared to homozygous carriers of the ins-allele. However, none of these risk estimates withstood adjustment for multiple comparisons. We found no strong gene-environment interactions between the examined polymorphism and diet and life style factors in relation to CRC risk.

Polymorphisms in NFKB1 and TLR4 and interaction with dietary and life style factors in relation to colorectal cancer in a Danish prospective case-cohort study.

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Tine Iskov Kopp

Full Text Available Maintenance of a balance between commensal bacteria and the mucosal immune system is crucial and intestinal dysbiosis may be a key event in the pathogenesis of colorectal cancer (CRC. The toll-like receptor 4 (TLR4 is an important pattern-recognition receptor that regulates inflammation and barrier function in the gut by a mechanism that involves activation of the nuclear factor-κB (NF-κB transcription factor. Dietary and life style factors may impact these functions. We therefore used a Danish prospective case-cohort study of 1010 CRC cases and 1829 randomly selected participants from the Danish Diet, Cancer and Health cohort to investigate three polymorphisms in NFKB1 and TLR4 and their possible interactions with diet and life style factors in relation to risk of CRC. Homozygous carriage of the variant allele of the TLR4/rs5030728 polymorphism was associated with increased risk of CRC (incidence rate ratio (IRR = 1.30; 95% confidence interval (CI: 1.05-1.60; P = 0.02 (gene-dose model; IRR = 1.24; 95%CI: 1.01-1.51; P = 0.04 (recessive model. Del-carriers of the NFKB1/rs28362491 polymorphism had a 17% (95%CI: 1.03-1.34; P = 0.02 increased risk of CRC compared to homozygous carriers of the ins-allele. However, none of these risk estimates withstood adjustment for multiple comparisons. We found no strong gene-environment interactions between the examined polymorphism and diet and life style factors in relation to CRC risk.

Dexmedetomidine reduces ventilator-induced lung injury (VILI by inhibiting Toll-like receptor 4 (TLR4/nuclear factor (NF-κB signaling pathway

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Hongli Chen

2018-02-01

Full Text Available Mechanical ventilation (MV may lead to ventilator-induced lung injury (VILI. Previous research has shown that dexmedetomidine attenuates pulmonary inflammation caused by MV, but the underlying mechanisms remain unclear. Our study aims to test whether dexmedetomidine has a protective effect against VILI and to explore the possible molecular mechanisms using the rat model. Thirty adult male Wistar rats weighing 200-250 g were randomly assigned to 5 groups (n = 6: control, low tidal volume MV (LMV, high tidal volume (HVT MV (HMV, HVT MV + dexmedetomidine (DEX, HVT MV + dexmedetomidine + yohimbine (DEX+Y. Rats were euthanized after being ventilated for 4 hours. Pathological changes, lung wet/dry (W/D weight ratio, lung myeloperoxidase (MPO activity, levels of inflammatory cytokines (i.e., interleukin [IL]-1β, tumor necrosis factor alpha [TNF-α], and IL-6 in the bronchoalveolar lavage fluid (BALF and lung tissues, expression of Toll-like receptor 4 (TLR4 and nuclear factor (NF-κB, and activation of NF-κB in lung tissues were measured. Compared with HMV, DEX group showed fewer pathological changes, lower W/D ratios and decreased MPO activity of the lung tissues and lower concentrations of the inflammatory cytokines in the BALF and lung tissues. Dexmedetomidine significantly inhibited the expression of TLR4 and NF-κB and activation of NF-κB. Yohimbine partly alleviated the effects of dexmedetomidine. Dexmedetomidine reduced the inflammatory response to HVT-MV and had a protective effect against VILI, with the inhibition of the TLR4/NF-κB signaling pathway, at least partly via α2-adrenoceptors.

The attenuated inflammation of MPL is due to the lack of CD14-dependent tight dimerization of the TLR4/MD2 complex at the plasma membrane.

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Tanimura, Natsuko; Saitoh, Shin-Ichiroh; Ohto, Umeharu; Akashi-Takamura, Sachiko; Fujimoto, Yukari; Fukase, Koichi; Shimizu, Toshiyuki; Miyake, Kensuke

2014-06-01

TLR4/MD-2 senses lipid A, activating the MyD88-signaling pathway on the plasma membrane and the TRIF-signaling pathway after CD14-mediated TLR4/MD-2 internalization into endosomes. Monophosphoryl lipid A (MPL), a detoxified derivative of lipid A, is weaker than lipid A in activating the MyD88-dependent pathway. Little is known, however, about mechanisms underlying the attenuated activation of MyD88-dependent pathways. We here show that MPL was impaired in induction of CD14-dependent TLR4/MD-2 dimerization compared with lipid A. Impaired TLR4/MD-2 dimerization decreased CD14-mediated TNFα production. In contrast, MPL was comparable to lipid A in CD14-independent MyD88-dependent TNFα production and TRIF-dependent responses including cell surface CD86 up-regulation and IFNβ induction. Although CD86 up-regulation is dependent on TRIF signaling, it was induced by TLR4/MD-2 at the plasma membrane. These results revealed that the attenuated MPL responses were due to CD14-initiated responses at the plasma membrane, but not just to responses initiated by MyD88, that is, MPL was specifically unable to induce CD14-dependent TLR4/MD-2 dimerization that selectively enhances MyD88-mediated responses at the plasma membrane. © The Japanese Society for Immunology. 2013. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The influence of TLR4 agonist lipopolysaccharides on hepatocellular carcinoma cells and the feasibility of its application in treating liver cancer.

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Gu, Junsheng; Sun, Ranran; Shen, Shen; Yu, Zujiang

2015-01-01

This study was designed to explore the influence of Toll-like receptor 4 (TLR4) agonist lipopolysaccharides (LPS) on liver cancer cell and the feasibility to perform liver cancer adjuvant therapy. Human liver cancer cell lines HepG2, H7402, and PLC/PRF/5 were taken as models, and the expression of TLRs mRNA was detected by real time-polymerase chain reaction method semiquantitatively. WST-1 method was used to detect the influence of LPS on the proliferation ability of liver cancer cells; propidium iodide (PI) single staining and Annexin V/PI double staining were used to test the influence of LPS on the cell cycle and apoptosis, respectively, on human liver cancer cell line H7402. Fluorescent quantitative polymerase chain reaction and Western blot method were used to determine the change of expression of Cyclin D1. The results demonstrated that most TLRs were expressed in liver cancer cells; stimulating TLR4 by LPS could upregulate TLR4 mRNA and the protein level, activate NF-κB signaling pathway downstream of TLR4, and mediate the generation of inflammatory factors IL-6, IL-8, and TNF-α; LPS was found to be able to strengthen the proliferation ability of liver cancer cells, especially H7402 cells; the expression of Cyclin D1 rose and H7402 cells were promoted to transit from G1 stage to S stage under the stimulation of LPS, but cell apoptosis was not affected. It was also found that LPS was able to activate signal transducer and activator of transcription -3 (STAT3) signaling pathway in H7402 cells and meanwhile significantly increase the initiation activity of STAT3; proliferation promoting effect of LPS to liver cancer cells remarkably lowered once STAT3 was blocked or inhibited. Thus, TLR4 agonist LPS is proved to be able to induce liver cancer cells to express inflammation factors and mediate liver cancer cell proliferation and generation of multidrug resistance by activating the cyclooxygenase-2/prostaglandin signal axis as well as the STAT3 pathway.

TLR-4 and CD14 Genotypes and Soluble CD14: Could They Predispose to Coronary Atherosclerosis?

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Maria Kalliopi Konstantinidou

2016-03-01

Full Text Available Background: Inflammatory mechanisms are key to the pathogenesis of atherosclerosis. Functional polymorphisms of TLR-4, Asp299Gly and Thr399Ile, CD14 promoter area C260T polymorphism and plasma levels of soluble CD14 are studied in subjects with Coronary Artery Disease (CAD. Methods: DNA was obtained from 100 human paraffin-embedded aortic specimens, from cadavers with known coronary atheromatosis (Group A and 100 blood samples from patients with CAD, as detected by cardiac Multi-Detector-row-Computed-Tomography (MDCT (Group B. Our control group consisted of 100 healthy individuals (Group C. Genotyping was performed by Restriction Fragment Length Polymorphism-Polymerase Chain Reaction (RFLP-PCR. Plasma levels of sCD14 were measured with ELISA. Results: For TLR-4 Asp299Gly and Thr399Ile polymorphisms, no statistically significant differences were observed. Regarding the C260T polymorphism, frequencies of T allele were significantly higher in the control group compared to the case group (p = 0.05. The Odds Ratio (OR showed statistically significant association of TT genotype with healthy individuals (OR 0.25, 95% Confidence Interval CI 0.10–0.62, p = 0.0017. Plasma levels of sCD14 in patients with CAD (mean value = 1.35 μg/mL were reduced when compared to reference value. Conclusions: The studied polymorphisms ofTLR-4 showed no association with CAD. Conversely, the functional polymorphism of CD14 has a statistically significant difference in expression between healthy and affected by CAD individuals.

Treatment of cyclic vomiting syndrome with co-enzyme Q10 and amitriptyline, a retrospective study

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Preston Amy

2010-01-01

Full Text Available Abstract Background Cyclic vomiting syndrome (CVS, which is defined by recurrent stereotypical episodes of nausea and vomiting, is a relatively-common disabling condition that is associated with migraine headache and mitochondrial dysfunction. Co-enzyme Q10 (Co-Q is a nutritional supplement that has demonstrated efficacy in pediatric and adult migraine. It is increasingly used in CVS despite the complete lack of studies to demonstrate its value in treatment Methods Using an Internet-based survey filled out by subjects with CVS or their parents, the efficacy, tolerability and subject satisfaction in CVS prophylaxis were queried. Subjects taking Co-Q (22 subjects were compared against those taking amitriptyline (162 subjects, which is the general standard-of-care. Results Subjects/parents reported similar levels of efficacy for a variety of episode parameters (frequency, duration, number of emesis, nausea severity. There was a 50% reduction in at least one of those four parameters in 72% of subjects treated with amitriptyline and 68% of subjects treated Co-Q. However, while no side effects were reported on Co-Q, 50% of subjects on amitriptyline reported side effects (P = 5 × 10-7, resulting in 21% discontinuing treatment (P = 0.007. Subjects/parents considered the benefits to outweigh the risks of treatment in 47% of cases on amitriptyline and 77% of cases on Co-Q (P = 0.008. Conclusion Our data suggest that the natural food supplement Co-Q is potentially efficacious and tolerable in the treatment of CVS, and should be considered as an option in CVS prophylaxis. Our data would likely be helpful in the design of a double-blind clinical trial.

TLR2 ligands induce NF-κB activation from endosomal compartments of human monocytes.

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Karim J Brandt

Full Text Available Localization of Toll-like receptors (TLR in subcellular organelles is a major strategy to regulate innate immune responses. While TLR4, a cell-surface receptor, signals from both the plasma membrane and endosomal compartments, less is known about the functional role of endosomal trafficking upon TLR2 signaling. Here we show that the bacterial TLR2 ligands Pam3CSK4 and LTA activate NF-κB-dependent signaling from endosomal compartments in human monocytes and in a NF-κB sensitive reporter cell line, despite the expression of TLR2 at the cell surface. Further analyses indicate that TLR2-induced NF-κB activation is controlled by a clathrin/dynamin-dependent endocytosis mechanism, in which CD14 serves as an important upstream regulator. These findings establish that internalization of cell-surface TLR2 into endosomal compartments is required for NF-κB activation. These observations further demonstrate the need of endocytosis in the activation and regulation of TLR2-dependent signaling pathways.

Andrographolide suppresses proliferation of human colon cancer SW620 cells through the TLR4/NF-κB/MMP-9 signaling pathway.

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Zhang, Rui; Zhao, Jian; Xu, Jian; Jiao, De-Xin; Wang, Jian; Gong, Zhi-Qiang; Jia, Jian-Hui

2017-10-01

Modern pharmacological research has revealed that andrographolide has various functions, including anti-bacterial, anti-inflammatory and anti-viral effects, immunoregulation, treating cardiovascular and cerebrovascular diseases, and prevention and treatment of alcoholic liver injury. The present study investigated whether andrographolide suppresses the proliferation of human colon cancer cell through the Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB/matrix metalloproteinase-9 (MMP-9) signaling pathway. The MTT assay and lactate dehydrogenase assay were used to evaluate the anticancer effects of andrographolide on cell proliferation and cytotoxicity in human colon cancer SW620 cells. Flow cytometry was used to analyze the anticancer effects of andrographolide on apoptosis by Annexin V-fluorescein isothiocyanate/propidium iodide kit. The effects of andrographolide on the activity of caspase-3/9 were measured using ELISA. Western blot analysis was also used to analyze the protein expression of TLR4, myeloid differentiation primary response gene 88 (MyD88), NF-κB-p65 and MMP-9. In the present study, it was found that andrographolide suppressed the cell proliferation, augmented cytotoxicity, evoked cell apoptosis and activated caspase-3/9 activities in human colon cancer SW620 cells. The results revealed that the anti-proliferation effects of andrographolide on the SW620 cells was associated with the inhibition of TLR4, MyD88, NF-κB-p65 and MMP-9 signaling activation. The results suggest that andrographolide is a promising drug for treatment of human colon cancer via suppression of the TLR4/NF-κB/MMP-9 signaling pathway.

Activated Charcoal Hemoperfusion in the Treatment of Experimental Amitriptyline Poisoning in Pigs - The Effect on Amitriptyline Plasma Concentration and Hemodynamic Parameters

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Jansen, Tejs; Petersen, Henrik; Malskaer, Cecilie M

2017-01-01

Coated activated charcoal hemoperfusion (CAC-HP) is a well-known treatment modality. Case reports have revealed conflicting results about the efficacy of CAC-HP in the treatment of amitriptyline (AT) poisoning, and no randomised clinical trials have been identified in the literature. This study a...... of AT compared to standard treatment alone. We hypothesize that the effect of modern CAC-HP as a treatment modality in AT poisoned human patients may be inadequate. This article is protected by copyright. All rights reserved....

TLR4-NOX4-AP-1 signaling mediates lipopolysaccharide-induced CXCR6 expression in human aortic smooth muscle cells

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Patel, Devang N.; Bailey, Steven R.; Gresham, John K.; Schuchman, David B.; Shelhamer, James H.; Goldstein, Barry J.; Foxwell, Brian M.; Stemerman, Michael B.; Maranchie, Jodi K.; Valente, Anthony J.; Mummidi, Srinivas; Chandrasekar, Bysani

2006-01-01

CXCL16 is a transmembrane non-ELR CXC chemokine that signals via CXCR6 to induce aortic smooth muscle cell (ASMC) proliferation. While bacterial lipopolysaccharide (LPS) has been shown to stimulate CXCL16 expression in SMC, its effects on CXCR6 are not known. Here, we demonstrate that LPS upregulates CXCR6 mRNA, protein, and surface expression in human ASMC. Inhibition of TLR4 with neutralizing antibodies or specific siRNA interference blocked LPS-mediated CXCR6 expression. LPS stimulated both AP-1 (c-Fos, c-Jun) and NF-κB (p50 and p65) activation, but only inhibition of AP-1 attenuated LPS-induced CXCR6 expression. Using dominant negative expression vectors and siRNA interference, we demonstrate that LPS induces AP-1 activation via MyD88, TRAF6, ERK1/2, and JNK signaling pathways. Furthermore, the flavoprotein inhibitor diphenyleniodonium chloride significantly attenuated LPS-mediated AP-1-dependent CXCR6 expression, as did inhibition of NOX4 NADPH oxidase by siRNA. Finally, CXCR6 knockdown inhibited CXCL16-induced ASMC proliferation. These results demonstrate that LPS-TLR4-NOX4-AP-1 signaling can induce CXCR6 expression in ASMC, and suggest that the CXCL16-CXCR6 axis may be an important proinflammatory pathway in the pathogenesis of atherosclerosis

Ghrelin protects the heart against ischemia/reperfusion injury via inhibition of TLR4/NLRP3 inflammasome pathway.

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Wang, Qin; Lin, Ping; Li, Peng; Feng, Li; Ren, Qian; Xie, Xiaofeng; Xu, Jing

2017-10-01

The aim of this study was to investigate the cardioprotective effects of ghrelin against myocardial ischemia/reperfusion (I/R) injury and the underlying mechanism. Sprague-Dawley rats were randomized into Sham, I/R and I/R+ghrelin groups. After 30 minutes ischemia, ghrelin (8nmol/kg) was injected intraperitoneally at the time of reperfusion in the I/R+ghrelin group. Then hemodynamic parameters were observed at 24h after reperfusion. Ghrelin exhibited dramatic improvement in cardiac functions, as manifested by increased LVSP and ±dP/dt max and decreased LVDP. At 24h after reperfusion, ghrelin significantly attenuated the myocardial infarction area and apoptosis, accompanied with a decrease in the levels of the myocyte injury marker enzymes. Oxidative stress injury and inflammatory response were also relieved by ghrelin. Western blot showed that the expression of TLR4, NLRP3, and caspase-1 were obviously increased in I/R group, while ghrelin significantly inhibited the I/R-induced TLR4, NLRP3, and caspase-1 expression. Ghrelin could inhibit the increased protein levels of NLRP3, caspase-1, and IL-1β induced by lipopolysacharide in primary cultured cardiomyocytes of neonatal rats. Ghrelin protected the heart against I/R injury by inhibiting oxidative stress and inflammation via TLR4/NLRP3 signaling pathway. Our results might provide new strategy and target for treatment of myocardial ischemia/reperfusion injury. Copyright © 2017 Elsevier Inc. All rights reserved.

Cellular Decision Making by Non-Integrative Processing of TLR Inputs

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Ryan A. Kellogg

2017-04-01

Full Text Available Cells receive a multitude of signals from the environment, but how they process simultaneous signaling inputs is not well understood. Response to infection, for example, involves parallel activation of multiple Toll-like receptors (TLRs that converge on the nuclear factor κB (NF-κB pathway. Although we increasingly understand inflammatory responses for isolated signals, it is not clear how cells process multiple signals that co-occur in physiological settings. We therefore examined a bacterial infection scenario involving co-stimulation of TLR4 and TLR2. Independent stimulation of these receptors induced distinct NF-κB dynamic profiles, although surprisingly, under co-stimulation, single cells continued to show ligand-specific dynamic responses characteristic of TLR2 or TLR4 signaling rather than a mixed response, comprising a cellular decision that we term “non-integrative” processing. Iterating modeling and microfluidic experiments revealed that non-integrative processing occurred through interaction of switch-like NF-κB activation, receptor-specific processing timescales, cell-to-cell variability, and TLR cross-tolerance mediated by multilayer negative feedback.

Andrographolide Suppress Tumor Growth by Inhibiting TLR4/NF-κB Signaling Activation in Insulinoma

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Zhang, Qian-Qian; Ding, Yi; Lei, Yan; Qi, Cui-Ling; He, Xiao-Dong; Lan, Tian; Li, Jiang-Chao; Gong, Ping; Yang, Xuesong; Geng, Jian-Guo; Wang, Li-Jing

2014-01-01

Insulinomas are rare tumors, and approximately 10% of insulinomas are malignant. Accumulating evidence has implicated that we still lack effective therapy to treat the patients who are diagnosed with rare malignant insulinoma. Previous studies have reported that Andrographolide (Andro) could inhibit cell cycle progression, reduce cell invasion and induce cell apoptosis in many common cancer cells. However, the effects of andro are cell type-dependent. So we emplored the β-TC-6 cells and the RIP1-Tag2 transgenic mouse model of endogenously growing insulinoma model to elucidate the possible anti-cancer effect of Andro on insulinoma, an uncommon type of malignant cancers in this study. Our experiments revealed that Andro significantly inhibited tumor growth at both the early-stage and the advanced-stage of insulinoma through targeting the TLR4/NF-κB signaling pathway. This work initially provides the evidence that the TLR4/NF-κB signaling pathway might be vital as a potential therapeutic target, and also indispensable in Andro-mediated anti-cancer effect in insulinoma. PMID:24719558

EGCG Maintains Th1/Th2 Balance and Mitigates Ulcerative Colitis Induced by Dextran Sulfate Sodium through TLR4/MyD88/NF-κB Signaling Pathway in Rats

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Xue Bing

2017-01-01

Full Text Available Objective. To observe the protective effect of epigallocatechin gallate (EGCG on dextran sulfate sodium- (DSS- induced ulcerative colitis in rats and to explore the roles of TLR4/MyD88/NF-κB signaling pathway. Methods. Rat models of ulcerative colitis were established by giving DSS. EGCG (50 mg/kg/d was given to assess disease activity index. HE staining was applied to observe histological changes. ELISA and qPCR detected the expression of inflammatory factors. Flow cytometry was used to measure the percentage of CD4+IFN-γ+ and CD4+IL-4+ in the spleen and colon. TLR4 antagonist E5564 was given in each group. Flow cytometry was utilized to detect CD4+IFN-γ+ and CD4+IL-4+ cells. Immunohistochemistry, qPCR, and western blot assay were applied to measure the expression of TLR4, MyD88, and NF-κB. Results. EGCG improved the intestinal mucosal injury in rats, inhibited production of inflammatory factors, maintained the balance of Th1/Th2, and reduced the expression of TLR4, MyD88, and NF-κB. After TLR4 antagonism, the protective effect of EGCG on intestinal mucosal injury was weakened in rats with ulcerative colitis, and the expressions of inflammatory factors were upregulated. Conclusion. EGCG can inhibit the intestinal inflammatory response by reducing the severity of ulcerative colitis and maintaining the Th1/Th2 balance through the TLR4/MyD88/NF-κB signaling pathway.

Gene polymorphisms and febrile neutropenia in acute leukemia--no association with IL-4, CCR-5, IL-1RA, but the MBL-2, ACE, and TLR-4 are associated with the disease in Turkish patients: a preliminary study.

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Pehlivan, Mustafa; Sahin, Handan Haydaroğlu; Ozdilli, Kurşat; Onay, Hüseyin; Ozcan, Ali; Ozkinay, Ferda; Pehlivan, Sacide

2014-07-01

The aim of this study was to investigate the mannose-binding lectin 2 (MBL-2), interleukin (IL)-4, Toll-like receptor 4 (TLR-4), angiotensin converting enzyme (ACE), chemokine receptor 5 (CCR-5), and IL-1 receptor antagonist (RA) gene polymorphisms (GPs) in acute leukemias (ALs) and to evaluate their roles in febrile neutropenia (FN) resulting from chemotherapy. The study included 60 AL patients hospitalized between the period of July 2001 and August 2006. Polymorphisms for the genes ACE(I/D), CCR-5, IL-1RA, MBL-2, TLR-4, and IL-4 were typed by polymerase chain reaction (PCR) and/or PCR-restriction fragment length polymerase. Genotype frequencies for these genes were compared in the patient and control groups. The relationships between the genotypes and the body distribution of infections, pathogens, the duration of neutropenia, and febrile episodes in AL patients were evaluated. No significant differences in either the genotype distribution or the allelic frequencies of TLR-4, IL-4, CCR-5, IL-1RN GPs were observed between patients and healthy controls. The AB/BB genotype (53.3%) in the MBL-2 gene was found to be significantly higher in the AL patients compared with control groups. There were correlations between the presence of MBL-2, TLR-4, and ACE polymorphisms and clinical parameters due to FN. Overall, bacteremia was more common in MBL BB and ACE DD. Gram-positive bacteremia was more common in ACE for ID versus DD genotype. Gram-negative bacteremia was more common for both the MBL-2 AB/BB genotype and TLR-4 AG genotype. Median durations of febrile episodes were significantly shorter in ACE DD and MBL AB/BB. Although TLR-4, ACE, and MBL-2 GPs have been extensively investigated in different clinical pictures, this is the first study to evaluate the role of these polymorphisms in the genetic etiopathogenesis of FN in patients with ALs. As a conclusion, TLR-4, ACE, and MBL-2 genes might play roles in the genetic etiopathogenesis of FN in patients with ALs.

The Role of TLR4, TNF-α and IL-1β in Type 2 Diabetes Mellitus Development within a North Indian Population.

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Doody, Natalie E; Dowejko, Monika M; Akam, Elizabeth C; Cox, Nick J; Bhatti, Jasvinder S; Singh, Puneetpal; Mastana, Sarabjit S

2017-07-01

This study investigated the role of IL-1β-511 (rs16944), TLR4-896 (rs4986790) and TNF-α-308 (rs1800629) polymorphisms in type 2 diabetes mellitus (T2DM) among an endogamous Northern Indian population. Four hundred fourteen participants (204 T2DM patients and 210 nondiabetic controls) were genotyped for IL-1β-511, TLR4-896 and TNF-α-308 loci. The C allele of IL-1β-511 was shown to increase T2DM susceptibility by 75% (OR: 1.75 [CI 1.32-2.33]). Having two parents affected by T2DM increased susceptibility by 5.7 times (OR: 5.693 [CI 1.431-22.648]). In this study, we have demonstrated a conclusive association with IL-1β-511 locus and IL-1β-511-TLR4-896 diplotype (CC-AA) and T2DM, which warrants further comprehensive analyses in larger cohorts. © 2017 John Wiley & Sons Ltd/University College London.

Association analysis identifies TLR7 and TLR8 as novel risk genes in asthma and related disorders

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Møller-Larsen, Steffen; Nyegaard, Mette; Haagerup, Annette

2008-01-01

the TLR7 and TLR8 genes. METHODS: We investigated the involvement of TLR7 and TLR8 in the aetiology of asthma and related disorders by a family based association analysis of two independently ascertained family samples comprising 540 and 424 individuals from 135 and 100 families, respectively. Ten...

Randomised clinical trial: the effects of amitriptyline on drinking capacity and symptoms in patients with functional dyspepsia, a double-blind placebo-controlled study

NARCIS (Netherlands)

Braak, B.; Klooker, T. K.; Wouters, M. M.; Lei, A.; van den Wijngaard, R. M.; Boeckxstaens, G. E.

2011-01-01

Functional dyspepsia is one of the most prevalent (15-40%) functional gastrointestinal disorders. Antidepressants such as amitriptyline are often used in these patients, but clinical studies are currently lacking. To evaluate the effect of 8 weeks of treatment with amitriptyline on drinking

Cold-inducible RNA-binding protein mediates cold air inducible airway mucin production through TLR4/NF-κB signaling pathway.

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Chen, Lingxiu; Ran, Danhua; Xie, Wenyue; Xu, Qing; Zhou, Xiangdong

2016-10-01

Mucus overproduction is an important feature in patients with chronic inflammatory airway diseases and cold air stimulation has been shown to be associated with the severity of these diseases. However, the regulatory mechanisms that mediate excessive mucin production under cold stress remain elusive. Recently, the cold-inducible RNA-binding protein (CIRP) has been shown to be markedly induced after exposure to cold air. In this study, we sought to explore the expression of CIRP within bronchial biopsy specimens, the effect on mucin5AC (MUC5AC) production in chronic inflammatory airway diseases and the potential signaling pathways involved in cold air stimulation process. We found that CIRP protein expression was significantly increased in patients with COPD and in mice treated with cold air. Moreover, cold air stimulation induced MUC5AC expression in wild-type mice but not in CIRP(-/-) mice. In vitro, cold air stress significantly elevated the transcriptional and protein expression levels of MUC5AC in human bronchial epithelial cells. CIRP, toll-like receptor 4 (TLR4) and phosphorylated NF-κB p65 (p-p65) increased significantly in response to cold stress and CIRP siRNA, TLR4 - neutralizing Ab and a specific inhibitor of NF-κB could attenuated cold stress inducible MUC5AC expression. In addition, CIRP siRNA could hindered the expression levels of TLR4 and p-p65 both induced by cold stress. Taken together, these results suggest that airway epithelial cells constitutively express CIRP in vitro and in vivo. CIRP is responsible for cold-inducible MUC5AC expression by activating TLR4/NF-κB signaling pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

Innate Immune Responses to TLR2 and TLR4 Agonists Differ between Baboons, Chimpanzees and Humans

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Brinkworth, Jessica F.; Pechenkina, Ekaterina A.; Silver, Jack; Goyert, Sanna M.

2012-01-01

Background African catarrhine primates differ in bacterial disease susceptibility. Methods Human, chimpanzee, and baboon blood was stimulated with TLR-detected bacterial agonists and cytokine/chemokine induction assessed by real-time pcr. Results Humans and chimpanzees shared similar cytokine/chemokine responses, while baboon cytokine/chemokine induction differed. Generally, responses were agonist-independent. Conclusions These primates tend to generate species rather than agonist–specific responses to bacterial agonists. PMID:22978822

Fisetin alleviates early brain injury following experimental subarachnoid hemorrhage in rats possibly by suppressing TLR 4/NF-κB signaling pathway.

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Zhou, Chen-hui; Wang, Chun-xi; Xie, Guang-bin; Wu, Ling-yun; Wei, Yong-xiang; Wang, Qiang; Zhang, Hua-sheng; Hang, Chun-hua; Zhou, Meng-liang; Shi, Ji-xin

2015-12-10

Early brain injury (EBI) determines the unfavorable outcomes after subarachnoid hemorrhage (SAH). Fisetin, a natural flavonoid, has anti-inflammatory and neuroprotection properties in several brain injury models, but the role of fisetin on EBI following SAH remains unknown. Our study aimed to explore the effects of fisetin on EBI after SAH in rats. Adult male Sprague-Dawley rats were randomly divided into the sham and SAH groups, fisetin (25mg/kg or 50mg/kg) or equal volume of vehicle was given at 30min after SAH. Neurological scores and brain edema were assayed. The protein expression of toll-like receptor 4 (TLR 4), p65, ZO-1 and bcl-2 was examined by Western blot. TLR 4 and p65 were also assessed by immunohistochemistry (IHC). Enzyme-linked immunosorbent assay (ELISA) was performed to detect the production of pro-inflammatory cytokines. Terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end-labeling (TUNEL) was perform to assess neural cell apoptosis. High-dose (50mg/kg) fisetin significantly improved neurological function and reduced brain edema at both 24h and 72h after SAH. Remarkable reductions of TLR 4 expression and nuclear factor κB (NF-κB) translocation to nucleus were detected after fisetin treatment. In addition, fisetin significantly reduced the productions of pro-inflammatory cytokines, decreased neural cell apoptosis and increased the protein expression of ZO-1 and bcl-2. Our data provides the evidence for the first time that fisetin plays a protective role in EBI following SAH possibly by suppressing TLR 4/NF-κB mediated inflammatory pathway. Copyright © 2015 Elsevier B.V. All rights reserved.

Amitriptyline up-regulates connexin43-gap junction in rat cultured cortical astrocytes via activation of the p38 and c-Fos/AP-1 signalling pathway.

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Morioka, N; Suekama, K; Zhang, F F; Kajitani, N; Hisaoka-Nakashima, K; Takebayashi, M; Nakata, Y

2014-06-01

Intercellular communication via gap junctions, comprised of connexin (Cx) proteins, allow for communication between astrocytes, which in turn is crucial for maintaining CNS homeostasis. The expression of Cx43 is decreased in post-mortem brains from patients with major depression. A potentially novel mechanism of tricyclic antidepressants is to increase the expression and functioning of gap junctions in astrocytes. The effect of amitriptyline on the expression of Cx43 and gap junction intercellular communication (GJIC) in rat primary cultured cortical astrocytes was investigated. We also investigated the role of p38 MAPK intracellular signalling pathway in the amitriptyline-induced expression of Cx43 and GJIC. Treatment with amitriptyline for 48 h significantly up-regulated Cx43 mRNA, protein and GJIC. The up-regulation of Cx43 was not monoamine-related since noradrenaline, 5-HT and dopamine did not induce Cx43 expression and pretreatment with α- and β-adrenoceptor antagonists had no effect. Intracellular signalling involved p38 MAPK, as amitriptyline significantly increased p38 MAPK phosphorylation and Cx43 expression and GJIC were significantly blocked by the p38 inhibitor SB 202190. Furthermore, amitriptyline-induced Cx43 expression and GJIC were markedly reduced by transcription factor AP-1 inhibitors (curcumin and tanshinone IIA). The translocation of c-Fos from the cytosol and the nucleus of cortical astrocytes was increased by amitriptyline, and this response was dependent on p38 activity. These findings indicate a novel mechanism of action of amitriptyline through cortical astrocytes, and further suggest that targeting this mechanism could lead to the development of a new class of antidepressants. © 2014 The British Pharmacological Society.

Pam2 lipopeptides systemically increase myeloid-derived suppressor cells through TLR2 signaling

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Maruyama, Akira; Shime, Hiroaki, E-mail: shime@med.hokudai.ac.jp; Takeda, Yohei; Azuma, Masahiro; Matsumoto, Misako; Seya, Tsukasa, E-mail: seya-tu@pop.med.hokudai.ac.jp

2015-02-13

Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that exhibit potent immunosuppressive activity. They are increased in tumor-bearing hosts and contribute to tumor development. Toll-like receptors (TLRs) on MDSCs may modulate the tumor-supporting properties of MDSCs through pattern-recognition. Pam2 lipopeptides represented by Pam2CSK4 serve as a TLR2 agonist to exert anti-tumor function by dendritic cell (DC)-priming that leads to NK cell activation and cytotoxic T cell proliferation. On the other hand, TLR2 enhances tumor cell progression/invasion by activating tumor-infiltrating macrophages. How MDSCs respond to TLR2 agonists has not yet been determined. In this study, we found intravenous administration of Pam2CSK4 systemically up-regulated the frequency of MDSCs in EG7 tumor-bearing mice. The frequency of tumor-infiltrating MDSCs was accordingly increased in response to Pam2CSK4. MDSCs were not increased by Pam2CSK4 stimuli in TLR2 knockout (KO) mice. Adoptive transfer experiments using CFSE-labeled MDSCs revealed that the TLR2-positive MDSCs survived long in tumor-bearing mice in response to Pam2CSK4 treatment. Since the increased MDSC population sustained immune-suppressive properties, our study suggests that Pam2CSK4-triggered TLR2 activation enhances the MDSC potential and suppress antitumor immune response in tumor microenvironment. - Highlights: • Pam2CSK4 administration induces systemic accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • TLR2 is essential for Pam2CSK4-induced accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • Pam2CSK4 supports survival of CD11b{sup +}Gr1{sup +} MDSCs in vivo.

mTOR inhibition in macrophages of asymptomatic HIV+ persons reverses the decrease in TLR4-mediated TNFα release through prolongation of MAPK pathway activation1

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Li, Xin; Han, Xinbing; Llano, Juliana; Bole, Medhavi; Zhou, Xiuqin; Swan, Katharine; Anandaiah, Asha; Nelson, Benjamin; Patel, Naimish R.; Reinach, Peter S.; Koziel, Henry; Tachado, Souvenir D.

2011-01-01

Toll-like receptor 4 (TLR4) mediated signaling is significantly impaired in macrophages from HIV+ persons predominantly due to altered MyD88-dependent pathway signaling caused in part by constitutive activation of PI3K. Here we assessed in these macrophages if the blunted increase in TLR4-mediated TNFα release induced by lipid A are associated with PI3K-induced upregulation of mammalian target of rapamycin (mTOR) activity. mTOR inhibition with rapamycin enhanced TLR4-mediated TNFα release, but instead suppressed anti-inflammatory IL-10 release. Targeted gene silencing of mTOR in macrophages resulted in lipid A-induced TNFα and IL-10 release patterns similar to those induced by rapamycin. Rapamycin restored MyD88-IRAK interaction in a dose-dependent manner. Targeted gene silencing of MyD88 (shRNA) and mTOR (RNAi) inhibition resulted in TLR4-mediated p70s6K activation and enhanced TNFα release, whereas IL-10 release was inhibited in both silenced and non-silenced HIV+ macrophages. Furthermore, mTOR inhibition augmented lipid A-induced TNFα release through enhanced and prolonged phosphorylation of ERK1/2 and JNK1/2 MAP kinases, which was associated with time-dependent MKP-1 destabilization. Taken together, impaired TLR4-mediated TNFα release in HIV+ macrophages is attributable in part to mTOR activation by constitutive PI3K expression in a MyD88-dependent signaling pathway. These changes result in MKP-1 stabilization, which shortens and blunts MAP kinase activation. mTOR inhibition may serve as a potential therapeutic target to upregulate macrophage innate immune host defense responsiveness in HIV+ persons. PMID:22025552

The Opening of ATP-Sensitive K+ Channels Protects H9c2 Cardiac Cells Against the High Glucose-Induced Injury and Inflammation by Inhibiting the ROS-TLR4-Necroptosis Pathway

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Weijie Liang

2017-02-01

Full Text Available Background/Aims: Hyperglycemia activates multiple signaling molecules, including reactive oxygen species (ROS, toll-like receptor 4 (TLR4, receptor-interacting protein 3 (RIP3, a kinase promoting necroptosis, which mediate hyperglycemia-induced cardiac injury. This study explored whether inhibition of ROS-TLR4-necroptosis pathway contributed to the protection of ATP-sensitive K+ (KATP channel opening against high glucose-induced cardiac injury and inflammation. Methods: H9c2 cardiac cells were treated with 35 mM glucose (HG to establish a model of HG-induced insults. The expression of RIP3 and TLR4 were tested by western blot. Generation of ROS, cell viability, mitochondrial membrane potential (MMP and secretion of inflammatory cytokines were measured as injury indexes. Results: HG increased the expression of TLR4 and RIP3. Necrostatin-1 (Nec-1, an inhibitor of necroptosis or TAK-242 (an inhibitor of TLR4 co-treatment attenuated HG-induced up-regulation of RIP3. Diazoxide (DZ, a mitochondrial KATP channel opener or pinacidil (Pin, a non-selective KATP channel opener or N-acetyl-L-cysteine (NAC, a ROS scavenger pre-treatment blocked the up-regulation of TLR4 and RIP3. Furthermore, pre-treatment with DZ or Pin or NAC, or co-treatment with TAK-242 or Nec-1 attenuated HG-induced a decrease in cell viability, and increases in ROS generation, MMP loss and inflammatory cytokines secretion. However, 5-hydroxy decanoic acid (5-HD, a mitochondrial KATP channel blocker or glibenclamide (Gli, a non-selective KATP channel blocker pre-treatment did not aggravate HG-induced injury and inflammation. Conclusion: KATP channel opening protects H9c2 cells against HG-induced injury and inflammation by inhibiting ROS-TLR4-necroptosis pathway.

TLR4-dependent internalization of CX3CR1 aggravates sepsis-induced immunoparalysis.

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Ge, Xin-Yu; Fang, Shang-Ping; Zhou, Miao; Luo, Jing; Wei, Juan; Wen, Xue-Ping; Yan, Xiao-Di; Zou, Zui

2016-01-01

Sepsis, the most severe manifestation of infection, poses a major challenge to health-care systems around the world. Limited ability to clean and remove the pathogen renders difficulty in septic patients to recover from the phase of immunoparalysis. The present study found the vital role of CX3CR1 internalization on sepsis-induced immunoparalysis. A mouse model with cecal ligation and puncture (CLP) and cell model with lipopolysaccharides (LPS) were employed to explore the relationship between CX3CR1 internalization and septic immunoparalysis. Immunoparalysis model in mice was established 4 days after CLP with significantly decreased proinflammatory cytokines. Flow cytometry analysis found a decreased surface expression of CX3CR1 during immunoparalysis, which was associated with reduced mRNA level and increased internalization of CX3CR1. G-protein coupled receptor kinase 2 (GRK2) and β-arrestin2 were significantly increased during septic immunoparalysis and involved in the internalization of CX3CR1. TLR4 -/- or TLR4 inhibitor-treated macrophages exhibited an inhibited expression of GRK2 and β-arrestin2, along with reduced internalization of CX3CR1. Moreover, the knockdown of GRK2 and β-arrestin2 inhibited the internalization of CX3CR1 and led to a higher response on the second hit, which was associated with an increased activation of NF-κB. The critical association between internalization of CX3CR1 and immunosuppression in sepsis may provide a novel reference for clinical therapeutics.

Tumor cell-released TLR4 ligands stimulate Gr-1+CD11b+F4/80+ cells to induce apoptosis of activated T cells.

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Liu, Yan-Yan; Sun, Ling-Cong; Wei, Jing-Jing; Li, Dong; Yuan, Ye; Yan, Bin; Liang, Zhi-Hui; Zhu, Hui-Fen; Xu, Yong; Li, Bo; Song, Chuan-Wang; Liao, Sheng-Jun; Lei, Zhang; Zhang, Gui-Mei; Feng, Zuo-Hua

2010-09-01

Gr-1(+)CD11b(+)F4/80(+) cells play important roles in tumor development and have a negative effect on tumor immunotherapy. So far, the mechanisms underlying the regulation of their immunosuppressive phenotype by classical and alternative macrophage activation stimuli are not well elucidated. In this study, we found that molecules from necrotic tumor cells (NTC-Ms) stimulated Gr-1(+)CD11b(+)F4/80(+) cells to induce apoptosis of activated T cells but not nonstimulated T cells. The apoptosis-inducing capacity was determined by higher expression levels of arginase I and IL-10 relative to those of NO synthase 2 and IL-12 in Gr-1(+)CD11b(+)F4/80(+) cells, which were induced by NTC-Ms through TLR4 signaling. The apoptosis-inducing capacity of NTC-Ms-stimulated Gr-1(+)CD11b(+)F4/80(+) cells could be enhanced by IL-10. IFN-gamma may reduce the apoptosis-inducing capacity of Gr-1(+)CD11b(+)F4/80(+) cells only if their response to IFN-gamma was not attenuated. However, the potential of Gr-1(+)CD11b(+)F4/80(+) cells to express IL-12 in response to IFN-gamma could be attenuated by tumor, partially due to the existence of active STAT3 in Gr-1(+)CD11b(+)F4/80(+) cells and NTC-Ms from tumor. In this situation, IFN-gamma could not effectively reduce the apoptosis-inducing capacity of Gr-1(+)CD11b(+)F4/80(+) cells. Tumor immunotherapy with 4-1BBL/soluble programmed death-1 may significantly reduce, but not abolish the apoptosis-inducing capacity of Gr-1(+)CD11b(+)F4/80(+) cells in local microenvironment. Blockade of TLR4 signaling could further reduce the apoptosis-inducing capacity of Gr-1(+)CD11b(+)F4/80(+) cells and enhance the suppressive effect of 4-1BBL/soluble form of programmed death-1 on tumor growth. These findings indicate the relationship of distinct signaling pathways with apoptosis-inducing capacity of Gr-1(+)CD11b(+)F4/80(+) cells and emphasize the importance of blocking TLR4 signaling to prevent the induction of T cell apoptosis by Gr-1(+)CD11b(+)F4/80(+) cells.

Dysregulation of toll-like receptor (TLR) 2 expression on monocytes and upregulation of the frequency of T cells expressing TLR2 in patients with chronic hepatitis C virus infection

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Ronit, Andreas; Salem, Mohammad; Hartling, Hans J

2013-01-01

Toll-like receptors (TLRs) initiate inflammatory responses that may play a role in disease progression in patients infected with hepatitis C virus (HCV). TLR2 and TLR4 surface expression were assessed on CD14(+) monocytes, CD4(+) and CD8(+) T cells in treatment naïve patients with chronic HCV...... infection with fibrosis, without fibrosis, co-infected with human immunodeficiency virus (HIV), and in healthy controls. Increased expression of TLR2 was found on monocytes in HCV-infected patients with fibrosis (p...

The anti-lung cancer activity of SEP is mediated by the activation and cytotoxicity of NK cells via TLR2/4 in vivo.

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Ke, Mengyun; Wang, Hui; Zhang, Min; Tian, Yuwei; Wang, Yizhou; Li, Bing; Yu, Jie; Dou, Jie; Xi, Tao; Zhou, Changlin

2014-05-01

Strongylocentrotus nudus egg polysaccharide (SEP) has been reported to display antitumor activity. However, the effects of SEP and its underlying mechanism in the treatment of lung cancer remain unclear, particularly with an immunodeficient mouse model of human non-small cell lung cancer (NSCLC). In the present study, we investigated the anti-lung cancer effects of SEP and its underlying mechanism of action in both Lewis lung cancer (LLC)-bearing C57/BL6J mice and human NSCLC H460-bearing nude mice. Although SEP showed no inhibitory effects on tumor cells in vitro, it markedly stimulated the percentage of CD3-NK1.1(+) cells and natural killer (NK) cell cytotoxicity in the spleens of nude mice and C57/BL6J mice. In LLC-bearing mice, SEP not only inhibited tumor growth but also promoted NK-mediated cytotoxicity, the NK1.1(+) cell population, and IL-2 and IFN-γ secretion. SEP significantly suppressed H460 growth in nude mice, which was abrogated by the selective depletion of NK cells via the intraperitoneal injection of anti-asialo GM-1 antibodies. Furthermore, anti-TLR2/4 antibodies blocked both SEP and NK cell binding and SEP-induced perforin secretion. SEP-induced proliferation and IFN-γ secretion by NK cells in wild type mice were partially impaired in TLR2 or TLR4 knockout mice. These results suggest that SEP-promoted NK cytotoxicity, which was partially mediated via TLR2 and TLR4, was the main contributing factor to lung cancer inhibition in vivo and that SEP may be a potential immunotherapy candidate for the treatment of lung cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

The Effects of Agaricus blazei Murill Polysaccharides on Cadmium-Induced Apoptosis and the TLR4 Signaling Pathway of Peripheral Blood Lymphocytes in Chicken.

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Liu, Wenjing; Ge, Ming; Hu, Xuequan; Lv, Ai; Ma, Dexing; Huang, Xiaodan; Zhang, Ruili

2017-11-01

In this study, we investigated the effects of Agaricus blazei Murill polysaccharides (ABP) on cadmium (Cd)-induced apoptosis and the TLR4 signaling pathway of chicken peripheral blood lymphocytes (PBLs). Seven-day-old healthy chickens were randomly divided into four groups, and each group contained 20 males. The cadmium-supplemented diet group (Cd group) was fed daily with full feed that contained 140 mg cadmium chloride (CdCl 2 )/kg and 0.2 mL saline. The A. blazei Murill polysaccharide diet group (ABP group) was fed daily with full feed with 0.2 mL ABP solution (30 mg/mL) by oral gavage. The cadmium-supplemented plus A. blazei Murill polysaccharide diet group (Cd + ABP group) was fed daily with full feed containing 140 mg CdCl 2 /kg and 0.2 mL ABP solution (30 mg/mL) by gavage. The control group was fed daily with full feed with 0.2 mL saline per day. We measured the apoptosis rate and messenger RNA (mRNA) levels of apoptosis genes (caspase-3, Bax, and Bcl-2), the mRNA levels of TLR4 and TLR4 signaling pathway-related factors (MyD88, TRIF, NF-κB, and IRF3), the TLR4 protein expression, and the concentrations of inflammatory cytokines (IL-1β, IL-6, and TNF-α) in chicken PBLs. The results showed that the PBL apoptosis rate was significantly increased, the mRNA levels of caspase-3 and Bax were significantly increased, while that of Bcl-2 was significantly reduced. The Bax/Bcl-2 ratio was significantly increased in the Cd group at 20, 40, and 60 days after treatment compared with that in the control group. After treatment with ABP, the above changes were clearly suppressed. At the same time, ABP reduced the concentrations of IL-1β, IL-6, and TNF-α induced by Cd. We also found that ABP inhibited the TLR4 mRNA level and protein expression and inhibited the mRNA levels of MyD88, TRIF, NF-κB, and IRF3. The results demonstrated that Cd could induce apoptosis, activate the TLR4 signaling pathway, and induce the expression of inflammatory cytokines in

Advanced Electrocardiogram Analysis in the Amitriptyline-poisoned Pig Treated with Activated Charcoal Haemoperfusion

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Jansen, Tejs; Hoegberg, Lotte C.G.; Eriksen, Thomas

2018-01-01

Coated activated charcoal haemoperfusion (CAC-HP) does not reduce the plasma concentration in amitriptyline (AT)-poisoned pigs. The aim of this non-blinded, randomized, controlled animal trial was to determine if CAC-HP reduces the pathological ECG changes caused by AT poisoning. Fourteen female...

Effect of the Total Extract of Averrhoacarambola (Oxalidaceae Root on the Expression Levels of TLR4 and NF-κB in Streptozotocin-Induced Diabetic Mice

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Xiaohui Xu

2015-07-01

Full Text Available Background: Averrhoacarambola L., which is a folk medicine used in diabetes mellitus (DM in ancient China, has been reported to have anti-diabetic efficacy. Aims: The aim of this study was to evaluate the hypoglycemic effect of the extract of Averrhoacarambola L. root (EACR on the regulation of the Toll-like receptor 4 (TLR4-Nuclear-factor kappa B (NF-κB pathway in B pathway in streptozotocin (STZ-induced diabetic mice. Methods: the mice were injected with STZ (120 mg/kg body weight via a tail vein. After 72 h, the mice with FBG = 11.1 mmol/L were confirmed as having diabetes. Subsequently, the mice were treated intragastrically with EACR (300, 600, 1200 mg/kg body weight/d and metformin (320 mg/kg body weight/d for 14 days. Results: As a result the serum fasting blood glucose (FBG, interleukin-6 (IL-6 and tumor necrosis factor-a (TNF-a levels were decreased following EACR administration. Immunohistochemical analysis revealed that the pancreatic tissue expression levels of TLR4 and NF-κB were downregulated after EACR administration. EACR suppressed pancreatic mRNA expression level of TLR4 and blocked the downstream NF-κB pathway in the pancreas. According to Western blot analysis EACR suppressed pancreatic TLR4 and NF-κB protein expression levels. Histopathological examination of the pancreas showed that STZ-induced pancreas lesions were alleviated by the EACR treatment. Conclusion: These findings suggest that the modulation of the IL-6 and TNF-a inflammatory cytokines and the suppression of the TLR4-NF-κB pathway are most likely involved in the anti-hyperglycemic effect of EACR in STZ-induced diabetic mice.

TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

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Cardoso, Elaine Cristina; Pereira, Nátalli Zanete; Mitsunari, Gabrielle Eimi; Oliveira, Luanda Mara da Silva; Ruocco, Rosa Maria S A; Francisco, Rossana Pulcineli Vieira; Zugaib, Marcelo; da Silva Duarte, Alberto José; Sato, Maria Notomi

2013-01-01

Mother-to-child transmission (MTCT) of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB) collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs) (TLR2, TLR4 and TLR5) and intracellular TLRs (TLR7, TLR7/8 and TLR9). Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs) from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097) stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7), IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7/8 pathway

TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

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Elaine Cristina Cardoso

Full Text Available Mother-to-child transmission (MTCT of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs (TLR2, TLR4 and TLR5 and intracellular TLRs (TLR7, TLR7/8 and TLR9. Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs and plasmacytoid DCs (pDCs to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097 stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7, IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7

Otitis media induced by peptidoglycan-polysaccharide (PGPS) in TLR2-deficient (Tlr2(-/-)) mice for developing drug therapy.

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Zhang, Xiaolin; Zheng, Tihua; Sang, Lu; Apisa, Luke; Zhao, Hongchun; Fu, Fenghua; Wang, Qingzhu; Wang, Yanfei; Zheng, Qingyin

2015-10-01

Toll like receptor 2 (TLR2) signaling can regulate the pathogenesis of otitis media (OM). However, the precise role of TLR2 signaling in OM has not been clarified due to the lack of an optimal animal model. Peptidoglycan-polysaccharide (PGPS) of the bacterial cell wall can induce inflammation by activating the TLR2 signaling. This study aimed at examining the pathogenic characteristics of OM induced by PGPS in Tlr2(-/-) mice, and the potential therapeutic effect of sodium aescinate (SA) in this model. Wild-type (WT) and Tlr2(-/-) mice were inoculated with streptococcal PGPS into their middle ears (MEs) and treated intravenously with vehicle or SA daily beginning at 3days prior to PGPS for 6 consecutive days. The pathologic changes of individual mice were evaluated longitudinally. In comparison with WT mice, Tlr2(-/-) mice were susceptible to PGPS-induced OM. Tlr2(-/-) mice displayed greater hearing loss, tympanic membrane damage, ME mucosal thickening, longer inflammation state, cilia and goblet cell loss. SA-treatment decreased neutrophil infiltration, modulated TLR2-related gene expression and improved ciliary organization. PGPS induced a relatively stable OM in Tlr2(-/-) mice, providing a new model for OM research. Treatment with SA mitigated the pathogenic damage in the ME and may be valuable for intervention of OM. Copyright © 2015 Elsevier B.V. All rights reserved.

Activation of TLR2 and TLR6 by Dengue NS1 Protein and Its Implications in the Immunopathogenesis of Dengue Virus Infection.

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Jincheng Chen

2015-07-01

Full Text Available Dengue virus (DV infection is the most prevalent mosquito-borne viral disease and its manifestation has been shown to be contributed in part by the host immune responses. In this study, pathogen recognition receptors, Toll-like receptor (TLR 2 and TLR6 were found to be up-regulated in DV-infected human PBMC using immunofluorescence staining, flow cytometry and Western blot analyses. Using ELISA, IL-6 and TNF-α, cytokines downstream of TLR2 and TLR6 signaling pathways were also found to be up-regulated in DV-infected PBMC. IL-6 and TNF-α production by PBMC were reduced when TLR2 and TLR6 were blocked using TLR2 and TLR6 neutralizing antibodies during DV infection. These results suggested that signaling pathways of TLR2 and TLR6 were activated during DV infection and its activation contributed to IL-6 and TNF-α production. DV NS1 protein was found to significantly increase the production of IL-6 and TNF-α when added to PBMC. The amount of IL-6 and TNF-α stimulated by DV NS1 protein was reduced when TLR2 and TLR6 were blocked, suggesting that DV NS1 protein is the viral protein responsible for the activation of TLR2 and TLR6 during DV infection. Secreted alkaline phosphatase (SEAP reporter assay was used to further confirm activation of TLR2 and TLR6 by DV NS1 protein. In addition, DV-infected and DV NS1 protein-treated TLR6-/- mice have higher survivability compared to DV-infected and DV NS1 protein-treated wild-type mice. Hence, activation of TLR6 via DV NS1 protein could potentially play an important role in the immunopathogenesis of DV infection.

The influence of TLR4 agonist lipopolysaccharides on hepatocellular carcinoma cells and the feasibility of its application in treating liver cancer

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Gu J

2015-08-01

Full Text Available Junsheng Gu, Ranran Sun, Shen Shen, Zujiang Yu Department of Infectious Diseases, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan, People’s Republic of China Objective: This study was designed to explore the influence of Toll-like receptor 4 (TLR4 agonist lipopolysaccharides (LPS on liver cancer cell and the feasibility to perform liver cancer adjuvant therapy. Methods: Human liver cancer cell lines HepG2, H7402, and PLC/PRF/5 were taken as models, and the expression of TLRs mRNA was detected by real time-polymerase chain reaction method semiquantitatively. WST-1 method was used to detect the influence of LPS on the proliferation ability of liver cancer cells; propidium iodide (PI single staining and Annexin V/PI double staining were used to test the influence of LPS on the cell cycle and apoptosis, respectively, on human liver cancer cell line H7402. Fluorescent quantitative polymerase chain reaction and Western blot method were used to determine the change of expression of Cyclin D1. Results: The results demonstrated that most TLRs were expressed in liver cancer cells; stimulating TLR4 by LPS could upregulate TLR4 mRNA and the protein level, activate NF-κB signaling pathway downstream of TLR4, and mediate the generation of inflammatory factors IL-6, IL-8, and TNF-α; LPS was found to be able to strengthen the proliferation ability of liver cancer cells, especially H7402 cells; the expression of Cyclin D1 rose and H7402 cells were promoted to transit from G1 stage to S stage under the stimulation of LPS, but cell apoptosis was not affected. It was also found that LPS was able to activate signal transducer and activator of transcription -3 (STAT3 signaling pathway in H7402 cells and meanwhile significantly increase the initiation activity of STAT3; proliferation promoting effect of LPS to liver cancer cells remarkably lowered once STAT3 was blocked or inhibited. Conclusion: Thus, TLR4 agonist LPS is proved to be able to

Hepatitis C Virus NS3 Mediated Microglial Inflammation via TLR2/TLR6 MyD88/NF-κB Pathway and Toll Like Receptor Ligand Treatment Furnished Immune Tolerance.

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Ayilam Ramachandran Rajalakshmy

Full Text Available Recent evidence suggests the neurotrophic potential of hepatitis C virus (HCV. HCV NS3 protein is one of the potent antigens of this virus mediating inflammatory response in different cell types. Microglia being the immune surveillance cells in the central nervous system (CNS, the inflammatory potential of NS3 on microglia was studied. Role of toll like receptor (TLR ligands Pam2CSK3 and Pam3CSK4 in controlling the NS3 mediated microglial inflammation was studied using microglial cell line CHME3.IL (Interleukin-8, IL-6, TNF-α (Tumor nicrosis factor alpha and IL-1β gene expressions were measured by semi quantitative RT-PCR (reverse transcription-PCR. ELISA was performed to detect IL-8, IL-6, TNF-α, IL-1β and IL-10 secretion. FACS (Flourescent activated cell sorting was performed to quantify TLR1, TLR2, TLR6, MyD88 (Myeloid differntiation factor 88, IkB-α (I kappaB alpha and pNF-κB (phosphorylated nuclear factor kappaB expression. Immunofluorescence staining was performed for MyD88, TLR6 and NF-κB (Nuclear factor kappaB. Student's t-test or One way analysis of variance with Bonferoni post hoc test was performed and p < 0.05 was considered significant.Microglia responded to NS3 by secreting IL-8, IL-6, TNF-α and IL-1β via TLR2 or TLR6 mediated MyD88/NF-κB pathway. Transcription factor NF-κB was involved in activating the cytokine gene expression and the resultant inflammatory response was controlled by NF-κB inhibitor, Ro106-9920, which is known to down regulate pro-inflammatory cytokine secretion. Activation of the microglia by TLR agonists Pam3CSK4 and Pam2CSK4 induced immune tolerance against NS3. TLR ligand treatment significantly down regulated pro-inflammatory cytokine secretion in the microglia. IL-10 secretion was suggested as the possible mechanism by which TLR agonists induced immune tolerance. NS3 as such was not capable of self-inducing immune tolerance in microglia.In conclusion, NS3 protein was capable of activating

The expression of Toll-like receptors 2, 4, 5, 7 and 9 in Merkel cell carcinoma.

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Jouhi, Lauri; Koljonen, Virve; Böhling, Tom; Haglund, Caj; Hagström, Jaana

2015-04-01

We sought to clarify whether the expression of toll-like receptors (TLR) in Merkel cell carcinoma (MCC) is linked to tumor and patient characteristics, especially the presence of Merkel cell polyoma virus (MCV). The study comprised of 128 patients with data on Merkel cell polyomavirus (MCV) status and clinical features were included in the study. Immunohistochemistry for TLR expression was performed on tissue microarray (TMA) slides. TLR 2, 4, 5, 7 and 9 expression was noted in most of the tumor specimens. Decreased expression of TLR 9 correlated strongly with MCV positivity. Cytoplasmic TLR 2 expression correlated with small tumor size, while nuclear TLR 2 and TLR 5 expressions with larger tumors. Increased nuclear TLR 4 expression and decreased TLR 7 expression were associated with older age. TLR 2, 4, 5, 7 and 9 appear to reflect certain clinicopathological variables and prognostic markers of MCC tumors. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Taurine Attenuates Hepatic Inflammation in Chronic Alcohol-Fed Rats Through Inhibition of TLR4/MyD88 Signaling.

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Lin, Chao-Jen; Chiu, Chun-Ching; Chen, Yi-Chen; Chen, Mu-Lin; Hsu, Tsai-Ching; Tzang, Bor-Show

2015-12-01

Accumulating evidence indicates that overconsumption of ethanol contributes in many ways to the pathogenesis of hepatic injury. Although studies indicate that taurine decreases lipogenesis, oxidative stress, and inflammatory cytokines, the protective effect of taurine against alcohol-induced liver injury is still unclear. To clarify the precise signaling involved in the beneficial effect of taurine on alcohol-induced liver injury, rats were randomly divided into four treatment groups: (1) control (Ctl), (2) alcohol (Alc), (3) Alc+taurine (Tau), and (4) Alc+silymarin (Sil). The Tau and Sil groups had lower lymphocyte infiltration and significantly lower TLR-4/MyD88 and IκB/NFκB compared to the Alc group. The inducible nitric oxide synthase (iNOS), C-reactive protein (CRP), tumor necrosis factors (TNF)-α, interleukin (IL)-6, and IL-1β were also significantly lower in the Tau and Sil groups than in the Alc group. The experimental results indicated that hepatoprotection against alcohol-induced inflammation may be mediated by decreased TLR-4/MyD88 signaling.

The TIR-domain containing adaptor TRAM is required for TLR7 mediated RANTES production.

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Enda Shevlin

Full Text Available Toll-like receptor 7 (TLR7 plays a vital role in the immune response to ssRNA viruses such as human rhinovirus (HRV and Influenza, against which there are currently no treatments or vaccines with long term efficacy available. Clearly, a more comprehensive understanding of the TLR7 signaling axis will contribute to its molecular targeting. TRIF related adaptor molecule (TRAM plays a vital role in TLR4 signaling by recruiting TRIF to TLR4, followed by endosomal trafficking of the complex and initiation of IRF3 dependent type I interferon production as well as NF-κB dependent pro-inflammatory cytokine production. Towards understanding the molecular mechanisms that regulate TLR7 functionality, we found that TRAM(-/- murine macrophages exhibited a transcriptional and translational impairment in TLR7 mediated RANTES, but not TNFα, production. Suppression of TRAM expression in human macrophages also resulted in an impairment in TLR7 mediated CCL5 and IFN-β, but not TNFα, gene induction. Furthermore, suppression of endogenous human TRAM expression in human macrophages significantly impaired RV16 induced CCL5 and IFNβ, but not TNFα gene induction. Additionally, TRAM-G2A dose-dependently inhibited TLR7 mediated activation of CCL5, IFNβ and IFNα reporter genes. TLR7-mediated phosphorylation and nuclear translocation of IRF3 was impaired in TRAM(-/- cells. Finally, co-immunoprecipitation studies indicated that TRAM physically interacts with MyD88 upon TLR7 stimulation, but not under basal conditions. Our results clearly demonstrate that TRAM plays a, hitherto unappreciated, role in TLR7 signaling through a novel signaling axis containing, but not limited to, MyD88, TRAM and IRF3 towards the activation of anti-viral immunity.

Topical amitriptyline and ketamine for post-herpetic neuralgia and other forms of neuropathic pain.

Science.gov (United States)

Sawynok, Jana; Zinger, Celia

2016-01-01

Neuropathic pain (NP) has several therapeutic options but efficacy is limited and adverse effects occur, such that additional treatment options are needed. A topical formulation containing amitriptyline 4% and ketamine 2% (AmiKet) may provide such an option. This report summarizes both published and unpublished results of clinical trials with AmiKet. In post-herpetic neuralgia (PHN), AmiKet produces a significant analgesia which is comparable to that produced by oral gabapentin. In diabetic painful neuropathy, AmiKet showed a strong trend towards pain reduction. In mixed neuropathic pain, case series reports suggest a favourable response rate, but are limited by trial characteristics. AmiKet is absorbed minimally following topical administration. Over 700 patients have now received topical AmiKet in clinical regimens, and it is well-tolerated with the adverse effects mainly being application site reactions. Both agents are polymodal, and several mechanisms may contribute to the peripheral efficacy of AmiKet. Topical AmiKet has the potential to be a first-line treatment option for PHN, and to be useful in other NP conditions. Furthermore, AmiKet has the potential to be an adjunct to systemic therapies, with the targeting of a peripheral compartment in addition to central sites of action representing a rational drug combination.

Andrographolide Ameliorates Liver Fibrosis in Mice: Involvement of TLR4/NF-κB and TGF-β1/Smad2 Signaling Pathways

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Liteng Lin

2018-01-01

Full Text Available Liver fibrosis is characterized by activated hepatic stellate cells (HSC and extracellular matrix accumulation. Blocking the activation of HSC and the inflammation response are two major effective therapeutic strategies for liver fibrosis. In addition to the long history of using andrographolide (Andro for inflammatory disorders, we aimed at elucidating the pharmacological effects and potential mechanism of Andro on liver fibrosis. In this study, liver fibrosis was induced by carbon tetrachloride (CCl4 and the mice were intraperitoneally injected with Andro for 6 weeks. HSC cell line (LX-2 and primary HSC were also treated with Andro in vitro. Treatment of CCl4-induced mice with Andro decreased the levels of alanine aminotransferase (ALT and aspartate aminotransferase (AST, Sirius red staining as well as the expression of α smooth muscle actin (α-SMA and transforming growth factor- (TGF- β1. Furthermore, the expression of Toll-like receptor (TLR4 and NF-κB p50 was also inhibited by Andro. Additionally, in vitro data confirmed that Andro treatment not only attenuated the expression of profibrotic and proinflammatory factors but also blocked the TGF-β1/Smad2 and TLR4/NF-κB p50 pathways. These results demonstrate that Andro prevents liver inflammation and fibrosis, which is in correlation with the inhibition of the TGF-β1/Smad2 and TLR4/NF-κB p50 pathways, highlighting Andro as a potential therapeutic strategy for liver fibrosis.

Lactobacillus rhamnosus GR-1 enhances NF-kappaB activation in Escherichia coli-stimulated urinary bladder cells through TLR4

Directory of Open Access Journals (Sweden)

Karlsson Mattias

2012-01-01

Full Text Available Abstract Background Epithelial cells of the urinary tract recognize pathogenic bacteria through pattern recognition receptors on their surface, such as toll-like receptors (TLRs, and mount an immune response through the activation of the NF-kappaB pathway. Some uropathogenic bacteria can subvert these cellular responses, creating problems with how the host eliminates pathogens. Lactobacillus is a genus of lactic acid bacteria that are part of the microbiota and consist of many probiotic strains, some specifically for urogenital infections. Immunomodulation has emerged as an important mode of action of probiotic and commensal lactobacilli and given the importance of epithelial cells, we evaluated the effect of the urogenital probiotic Lactobacillus rhamnosus GR-1 on epithelial immune activation. Results Immune activation through the NF-kappaB pathway was initiated by stimulation of T24 urothelial cells with heat-killed Escherichia coli and this was further potentiated when cells were co-cultured with live L. rhamnosus GR-1. Heat-killed lactobacilli were poor activators of NF-kappaB. Concomitant stimulation of bladder cells with E. coli and L. rhamnosus GR-1 increased the levels of the pro-inflammatory cytokine TNF, whereas IL-6 and CXCL8 levels were reduced. Another probiotic, L. rhamnosus GG, was also able to potentiate NF-kappaB in these cells although at a significantly reduced level compared to the GR-1 strain. The transcript numbers and protein levels of the lipopolysaccharide receptor TLR4 were significantly increased after co-stimulation with E. coli and lactobacilli compared to controls. Furthermore, inhibition of TLR4 activation by polymixin B completely blocked the lactobacilli potentiation of NF-kappaB. Conclusions The immunological outcome of E. coli challenge of bladder cells was influenced by probiotic L. rhamnosus GR-1, by enhancing the activation of NF-kappaB and TNF release. Thus the urogenital probiotic L. rhamnosus GR-1

The Processed Amino-Terminal Fragment of Human TLR7 Acts as a Chaperone To Direct Human TLR7 into Endosomes

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Shepherd, Dawn; Booth, Sarah; Waithe, Dominic; Reis e Sousa, Caetano

2015-01-01

TLR7 mediates innate immune responses to viral RNA in endocytic compartments. Mouse and human (h)TLR7 undergo proteolytic cleavage, resulting in the generation of a C-terminal fragment that accumulates in endosomes and associates with the signaling adaptor MyD88 upon receptor triggering by TLR7 agonists. Although mouse TLR7 is cleaved in endosomes by acidic proteases, hTLR7 processing can occur at neutral pH throughout the secretory pathway through the activity of furin-like proprotein convertases. However, the mechanisms by which cleaved hTLR7 reaches the endosomal compartment remain unclear. In this study, we demonstrate that, after hTLR7 proteolytic processing, the liberated amino (N)-terminal fragment remains bound to the C terminus through disulfide bonds and provides key trafficking information that ensures correct delivery of the complex to endosomal compartments. In the absence of the N-terminal fragment, the C-terminal fragment is redirected to the cell surface, where it is functionally inactive. Our data reveal a novel role for the N terminus of hTLR7 as a molecular chaperone that provides processed hTLR7 with the correct targeting instructions to reach the endosomal compartment, hence ensuring its biological activity and preventing inadvertent cell surface responses to self-RNA. PMID:25917086

Sex-specific effects of TLR9 promoter variants on spontaneous clearance of HCV infection.

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Fischer, Janett; Weber, Alexander N R; Böhm, Stephan; Dickhöfer, Sabine; El Maadidi, Souhayla; Deichsel, Danilo; Knop, Viola; Klinker, Hartwig; Möller, Bernd; Rasenack, Jens; Wang, Lisa; Sharma, Manu; Hinrichsen, Holger; Spengler, Ulrich; Buggisch, Peter; Sarrazin, Christoph; Pawlita, Michael; Waterboer, Tim; Wiese, Manfred; Probst-Müller, Elsbeth; Malinverni, Raffaele; Bochud, Pierre-Yves; Gardiner, Clair; O'Farrelly, Cliona; Berg, Thomas

2017-10-01

As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression. Therefore, the TLR9 SNPs and the interferon lambda 4 ( IFNL4 ) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers. The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women. TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Polymorphisms in NFKB1 and TLR4 and Interaction with Dietary and Life Style Factors in Relation to Colorectal Cancer in a Danish Prospective Case-Cohort Study

DEFF Research Database (Denmark)

Kopp, Tine Iskov; Andersen, Vibeke; Tjoøneland, Anne

2015-01-01

Maintenance of a balance between commensal bacteria and the mucosal immune system is crucial and intestinal dysbiosis may be a key event in the pathogenesis of colorectal cancer (CRC). The toll-like receptor 4 (TLR4) is an important pattern-recognition receptor that regulates inflammation...... and barrier function in the gut by a mechanism that involves activation of the nuclear factor-kappa B (NF-kappa B) transcription factor. Dietary and life style factors may impact these functions. We therefore used a Danish prospective case-cohort study of 1010 CRC cases and 1829 randomly selected participants...... from the Danish Diet, Cancer and Health cohort to investigate three polymorphisms in NFKB1 and TLR4 and their possible interactions with diet and life style factors in relation to risk of CRC. Homozygous carriage of the variant allele of the TLR4/rs5030728 polymorphism was associated with increased...

Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation

OpenAIRE

Kirschning, Carsten J; Dreher, Stefan; Maa?, Bj?rn; Fichte, Sylvia; Schade, Jutta; K?ster, Mario; Noack, Andreas; Lindenmaier, Werner; Wagner, Hermann; B?ldicke, Thomas

2010-01-01

Abstract Background Toll-like receptor (TLR) 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs) of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs) contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies) are applied to blo...

Diclofenac pretreatment modulates exercise-induced inflammation in skeletal muscle of rats through the TLR4/NF-κB pathway.

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Barcelos, Rômulo Pillon; Bresciani, Guilherme; Cuevas, Maria José; Martínez-Flórez, Susana; Soares, Félix Alexandre Antunes; González-Gallego, Javier

2017-07-01

Nonsteroidal anti-inflammatory drugs, such as diclofenac, are widely used to treat inflammation and pain in several conditions, including sports injuries. This study analyzes the influence of diclofenac on the toll-like receptor-nuclear factor kappa B (TLR-NF-κB) pathway in skeletal muscle of rats submitted to acute eccentric exercise. Twenty male Wistar rats were divided into 4 groups: control-saline, control-diclofenac, exercise-saline, and exercise-diclofenac. Diclofenac or saline were administered for 7 days prior to an acute eccentric exercise bout. The inflammatory status was evaluated through mRNA levels of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNF-α), and protein content of COX-2, IL-6, and TNF-α in vastus lateralis muscle. Data obtained showed that a single bout of eccentric exercise significantly increased COX-2 gene expression. Similarly, mRNA expression and protein content of other inflammation-related genes also increased after the acute exercise. However, these effects were attenuated in the exercise + diclofenac group. TLR4, myeloid differentiation primary response gene 88 (MyD88), and p65 were also upregulated after the acute eccentric bout and the effect was blunted by the anti-inflammatory drug. These findings suggest that pretreatment with diclofenac may represent an effective tool to ameliorate the pro-inflammatory status induced by acute exercise in rat skeletal muscle possibly through an attenuation of the TLR4-NF-κB signaling pathway.

The inflammatory cytokine effect of Pam3CSK4 TLR2 agonist alone or in combination with Leishmania infantum antigen on ex-vivo whole blood from sick and resistant dogs.

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Martínez-Orellana, Pamela; Quirola-Amores, Paulina; Montserrat-Sangrà, Sara; Ordeix, Laura; Llull, Joan; Álvarez-Fernández, Alejandra; Solano-Gallego, Laia

2017-03-13

A wide spectrum of clinical manifestations and immune responses exist in canine L. infantum infection. Ibizan hounds are more "resistant" to disease than other dog breeds. Recognition of pathogen-associated molecule patterns by toll like receptors (TLRs) rapidly triggers a variety of anti-microbial immune responses through the induction of pro-inflammatory cytokines such as TNF-α and IL-6 which may play an important role in controlling Leishmania infection. The main objective of this study was to investigate and compare the effect of a TLR2 agonist (TLR2a) alone or in combination with L. infantum antigen (LSA) on ex vivo whole blood cytokine production from healthy seronegative IFN-γ non-producer dogs from an area of low in canine leishmaniosis endemicity (n = 11); sick seropositive dogs with low production of IFN-γ (n = 17) and healthy seronegative or low positive Ibizan hounds with a predominant IFN-γ production (n = 21) from a highly endemic area. Whole blood was stimulated with medium alone (Ø), LSA, concanavalin A, TLR2 (Pam3CSK4) receptor agonist (Ø + TLR2a) and TLR2a and LSA (LSA + TLR2a) for 48 h. Supernatants were harvested for measurement of canine TNF-α and IL-6 cytokines by ELISA. A significant increase of TNF-α was found in the supernatants of stimulated blood from all groups (Ø + TLR2a and LSA + TLR2a) when compared with medium alone. A similar pattern was observed for IL-6. Interestingly, a significant increase of TNF-α production was only observed when stimulation with LSA + TLR2a was compared with TLR2a alone in Ibizan hounds. A significant increase of TNF-α production was observed with stimulation of LSA + TLR2a when compared with LSA in all groups. Significantly higher concentrations of TNF-α and IL-6 were detected in Ibizan hounds, especially for the Ø + TLR2a and LSA + TLR2a treatments compared with other groups. This study demonstrated that TLR2a alone enhances the production of the

TLR2 and TLR9 Synergistically Control Herpes Simplex Virus Infection in the Brain

DEFF Research Database (Denmark)

Sørensen, Louise Nørgaard; Reinert, Line; Malmgaard, Lene

2008-01-01

Viruses are recognized by the innate immune system through pattern recognition receptors (PRRs). For instance, HSV virions and genomic DNA are recognized by TLR2 and TLR9, respectively. Although several viruses and viral components have been shown to stimulate cells through TLRs, only very few st...

A Randomized Controlled Trial on the Effectiveness of Court-Type Traditional Thai Massage versus Amitriptyline in Patients with Chronic Tension-Type Headache

Directory of Open Access Journals (Sweden)

Peerada Damapong

2015-01-01

Full Text Available This study aimed to evaluate the effectiveness of the court-type traditional Thai massage (CTTM to treat patients with chronic tension-type headaches (CTTHs comparing with amitriptyline taking. A randomized controlled trial was conducted. Sixty patients diagnosed with CTTH were equally divided into a treatment and a control group. The treatment group received a 45-minute course of CTTM twice per week lasting 4 weeks while the control group was prescribed 25 mg of amitriptyline once a day before bedtime lasting 4 weeks. Outcome measures were evaluated in week 2, week 4 and followed up in week 6 consisting of visual analog scale (VAS, tissue hardness, pressure pain threshold (PPT, and heart rate variability (HRV. The results demonstrated a significant decrease in VAS pain intensity for the CTTM group at different assessment time points while a significant difference occurred in within-group and between-group comparison (P < 0.05 for each evaluated measure. Moreover, the tissue hardness of the CTTM group was significantly lower than the control group at week 4 (P < 0.05. The PPT and HRV of the CTTM group were significantly increased (P < 0.05. CTTM could be an alternative therapy for treatment of patients with CTTHs.

Attenuation of LPS-induced inflammation by ICT, a derivate of icariin, via inhibition of the CD14/TLR4 signaling pathway in human monocytes.

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Wu, Jinfeng; Zhou, Junmin; Chen, Xianghong; Fortenbery, Nicole; Eksioglu, Erika A; Wei, Sheng; Dong, Jingcheng

2012-01-01

To evaluate the anti-inflammatory potential of ICT in LPS stimulated human innate immune cells. 3, 5, 7-Trihydroxy-4'-methoxy-8-(3-hydroxy-3- methylbutyl)-flavone (ICT) is a novel derivative of icariin, the major active ingredient of Herba Epimedii, an herb used in traditional Chinese medicine. We previously demonstrated its anti-inflammatory potential in a murine macrophage cell line as well as in mouse models. We measured TNF-α production by ELISA, TLR4/CD14 expression by flow cytometry, and NF-κB and MAPK activation by western blot all in LPS-stimulated PBMC, human monocytes, or THP-1 cells after treatment with ICT. ICT inhibited LPS-induced TNF-α production in THP-1 cells, PBMCs and human monocytes in a dose-dependent manner. ICT treatment resulted in down-regulation of the expression of CD14/TLR4 and attenuated NF-κB and MAPK activation induced by LPS. We illustrate the anti-inflammatory property of ICT in human immune cells, especially in monocytes. These effects were mediated, at least partially, via inhibition of the CD14/TLR4 signaling pathway. Copyright © 2011 Elsevier B.V. All rights reserved.

Cobalt Alloy Implant Debris Induces Inflammation and Bone Loss Primarily through Danger Signaling, Not TLR4 Activation: Implications for DAMP-ening Implant Related Inflammation

OpenAIRE

Samelko, Lauryn; Landgraeber, Stefan; McAllister, Kyron; Jacobs, Joshua; Hallab, Nadim James

2016-01-01

Cobalt alloy debris has been implicated as causative in the early failure of some designs of current total joint implants. The ability of implant debris to cause excessive inflammation via danger signaling (NLRP3 inflammasome) vs. pathogen associated pattern recognition receptors (e.g. Toll-like receptors; TLRs) remains controversial. Recently, specific non-conserved histidines on human TLR4 have been shown activated by cobalt and nickel ions in solution. However, whether this TLR activation ...

Gold-quercetin nanoparticles prevent metabolic endotoxemia-induced kidney injury by regulating TLR4/NF-κB signaling and Nrf2 pathway in high fat diet fed mice.

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Xu, Min-Xuan; Wang, Ming; Yang, Wei-Wei

2017-01-01

High-fat diet-induced metabolic syndrome followed by chronic kidney disease caused by intestinal endotoxemia have received extensive attention. Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) and oxidative stress-related Nrf2/Keap1 were regarded as the key target points involved in metabolic inflammation and kidney injury. However, the molecular mechanism of interaction between TLR4/NF-κB and Nrf2 activation in high-fat diet-induced renal injury is not absolutely understood. Quercetin, a natural product, has been reported to possess antitumor and anti-inflammatory effects. In this regard, this study attempted to prepare poly(d,l-lactide- co -glycolide)-loaded gold nanoparticles precipitated with quercetin (GQ) to investigate the anti-inflammatory and anti-oxidative stress effects in high-fat diet-induced kidney failure. For this study, C57BL/6 mice fed fat-rich fodder were used as the metabolic syndrome model to evaluate the protective effects of GQ on kidney injury and to determine whether TLR4/NF-κB and Nrf2 pathways were associated with the process. Moreover, histological examinations, enzyme-linked immunosorbent assay, Western blot, and basic blood tests and systemic inflammation-related indicators were used to investigate the inhibitory effects of GQ and underlying molecular mechanism by which it may reduce renal injury. Of note, podocyte injury was found to participate in endotoxin-stimulated inflammatory response. TLR4/NF-κB and Nrf2 pathways were upregulated with high-fat diet intake in mice, resulting in reduction of superoxide dismutase activity and increase in superoxide radical, H 2 O 2 , malondialdehyde, XO, XDH, and XO/XDH ratio. In addition, upregulation of TLR4/NF-κB and oxidative stress by endotoxin were observed in vitro, which were suppressed by GQ administration, ultimately alleviating podocyte injury. These findings indicated that GQ could restore the metabolic disorders caused by high-fat diet, which suppresses insulin

Effects of total glucosides of paeony on immune regulatory toll-like receptors TLR2 and 4 in the kidney from diabetic rats.

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Xu, Xing-xin; Qi, Xiang-Ming; Zhang, Wei; Zhang, Chao-Qun; Wu, Xiao-Xu; Wu, Yong-Gui; Wang, Kun; Shen, Ji-Jia

2014-05-15

TLRs are a family of receptors that play a critical role in the pathogenesis of diabetic nephropathy. TGP have been shown to have anti-inflammatory and immuno-regulatory activities. However, the relation between TGP and TLRs on diabetic nephropathy remains unknown. In this study, we examined effects of TGP on immune regulatory TLR2 and 4 in the kidney from streptozotocin-induced diabetic rats. TGP decreased the levels of 24h urinary albumin excretion rate significantly in diabetic rats. Western blot analysis showed that TGP significantly inhibited the expression of TLR2 and 4, MyD88, p-IRAK1, NF-κB p65, p-IRF3, TNF-α and IL-1β. Quantitative real-time PCR analysis showed that the significantly increased levels of TLR2 and 4, and MyD88mRNA in the kidneys of diabetic rats were significantly suppressed by TGP treatment. Macrophages infiltration were also markedly increased in the kidneys of the diabetic rats, but were significantly inhibited by TGP in a dose-dependent manner. These results suggest that TGP has protective effects on several pharmacological targets in the progress of diabetic nephropathy by selectively blocking TLRs activation in vivo. Copyright © 2013 Elsevier GmbH. All rights reserved.

TLR-mediated inflammatory responses to Streptococcus pneumoniae are highly dependent on surface expression of bacterial lipoproteins.

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Tomlinson, Gillian; Chimalapati, Suneeta; Pollard, Tracey; Lapp, Thabo; Cohen, Jonathan; Camberlein, Emilie; Stafford, Sian; Periselneris, Jimstan; Aldridge, Christine; Vollmer, Waldemar; Picard, Capucine; Casanova, Jean-Laurent; Noursadeghi, Mahdad; Brown, Jeremy

2014-10-01

Streptococcus pneumoniae infections induce inflammatory responses that contribute toward both disease pathogenesis and immunity, but the host-pathogen interactions that mediate these effects are poorly defined. We used the surface lipoprotein-deficient ∆lgt pneumococcal mutant strain to test the hypothesis that lipoproteins are key determinants of TLR-mediated immune responses to S. pneumoniae. We show using reporter assays that TLR2 signaling is dependent on pneumococcal lipoproteins, and that macrophage NF-κB activation and TNF-α release were reduced in response to the ∆lgt strain. Differences in TNF-α responses between Δlgt and wild-type bacteria were abrogated for macrophages from TLR2- but not TLR4-deficient mice. Transcriptional profiling of human macrophages revealed attenuated TLR2-associated responses to ∆lgt S. pneumoniae, comprising many NF-κB-regulated proinflammatory cytokine and chemokine genes. Importantly, non-TLR2-associated responses were preserved. Experiments using leukocytes from IL-1R-associated kinase-4-deficient patients and a mouse pneumonia model confirmed that proinflammatory responses were lipoprotein dependent. Our data suggest that leukocyte responses to bacterial lipoproteins are required for TLR2- and IL-1R-associated kinase-4-mediated inflammatory responses to S. pneumoniae. Copyright © 2014 The Authors.

Divergent effects of Tenofovir and Retrovir (AZT) on TLR-mediated cytokine production

DEFF Research Database (Denmark)

Melchjorsen, Jesper; Tolstrup, Martin; Paludan, Søren Riis

  Pathogen-recognizing Toll-like receptors 2 (TLR2) and TLR4 are known to recognize a number of pathogens, including E.Coli, S. Pneumoniae and N. Meningitidis. We have studied whether a number of HIV therapeutics affect immediate proinflammatory cytokine responses in cell cultures. Preliminary...

Modulation of neonatal microbial recognition: TLR-mediated innate immune responses are specifically and differentially modulated by human milk.

Science.gov (United States)

LeBouder, Emmanuel; Rey-Nores, Julia E; Raby, Anne-Catherine; Affolter, Michael; Vidal, Karine; Thornton, Catherine A; Labéta, Mario O

2006-03-15

The mechanisms controlling innate microbial recognition in the neonatal gut are still to be fully understood. We have sought specific regulatory mechanisms operating in human breast milk relating to TLR-mediated microbial recognition. In this study, we report a specific and differential modulatory effect of early samples (days 1-5) of breast milk on ligand-induced cell stimulation via TLRs. Although a negative modulation was exerted on TLR2 and TLR3-mediated responses, those via TLR4 and TLR5 were enhanced. This effect was observed in human adult and fetal intestinal epithelial cell lines, monocytes, dendritic cells, and PBMC as well as neonatal blood. In the latter case, milk compensated for the low capacity of neonatal plasma to support responses to LPS. Cell stimulation via the IL-1R or TNFR was not modulated by milk. This, together with the differential effect on TLR activation, suggested that the primary effect of milk is exerted upstream of signaling proximal to TLR ligand recognition. The analysis of TLR4-mediated gene expression, used as a model system, showed that milk modulated TLR-related genes differently, including those coding for signal intermediates and regulators. A proteinaceous milk component of > or =80 kDa was found to be responsible for the effect on TLR4. Notably, infant milk formulations did not reproduce the modulatory activity of breast milk. Together, these findings reveal an unrecognized function of human milk, namely, its capacity to influence neonatal microbial recognition by modulating TLR-mediated responses specifically and differentially. This in turn suggests the existence of novel mechanisms regulating TLR activation.

Divergent expression of bacterial wall sensing Toll-like receptors 2 and 4 in colorectal cancer.

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Paarnio, Karoliina; Väyrynen, Sara; Klintrup, Kai; Ohtonen, Pasi; Mäkinen, Markus J; Mäkelä, Jyrki; Karttunen, Tuomo J

2017-07-14

To characterize the expression of toll-like receptors (TLR) 2 and 4 in colorectal cancer (CRC) and in normal colorectal mucosa. We analysed tissue samples from a prospective series of 118 unselected surgically treated patients with CRC. Sections from formalin fixed, paraffin embedded specimens were analysed for TLR2 and TLR4 expression by immunohistochemistry. Two independent assessors evaluated separately expression at the normal mucosa, at the invasive front and the bulk of the carcinoma, and in the lymph node metastases when present. Expression levels in different locations were compared and their associations with clinicopathological features including TNM-stage and the grade of the tumour and 5-year follow-up observations were analysed. Normal colorectal epithelium showed a gradient of expression of both TLR2 and TLR4 with low levels in the crypt bases and high levels in the surface. In CRC, expression of both TLRs was present in all cases and in the major proportion of tumour cells. Compared to normal epithelium, TLR4 expression was significantly weaker but TLR2 expression stronger in carcinoma cells. Weak TLR4 expression in the invasive front was associated with distant metastases and worse cancer-specific survival at 5 years. In tumours of the proximal colon the cancer-specific survival at 5 years was 36.9% better with strong TLR4 expression as compared with those with weak expression ( P = 0.044). In contrast, TLR2 expression levels were not associated with prognosis. Tumour cells in the lymph node metastases showed higher TLR4 expression and lower TLR2 expression than cells in primary tumours. Tumour cells in CRC show downregulation of TLR4 and upregulation of TLR2. Low expression of TLR4 in the invasive front predicts poor prognosis and metastatic disease.

Gold-quercetin nanoparticles prevent metabolic endotoxemia-induced kidney injury by regulating TLR4/NF-kB signaling and Nrf2 pathway in high fat diet fed mice

Directory of Open Access Journals (Sweden)

Xu MX

2017-01-01

Full Text Available Min-Xuan Xu,1,2,* Ming Wang,3,* Wei-Wei Yang4 1Chongqing Key Laboratory of Medicinal Resources in the Three Gorges Reservoir Region, School of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, 2College of Engineering and Applied Sciences, Nanjing University, Nanjing, 3Department of Urology, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 4Department of Nephrology, Huai’an First People’s Hospital, Nanjing Medical University, Jiangsu, People’s Republic of China *These authors contributed equally to this work Abstract: High-fat diet-induced metabolic syndrome followed by chronic kidney disease caused by intestinal endotoxemia have received extensive attention. Toll-like receptor 4 (TLR4/nuclear factor-kappa B (NF-κB and oxidative stress-related Nrf2/Keap1 were regarded as the key target points involved in metabolic inflammation and kidney injury. However, the molecular mechanism of interaction between TLR4/NF-κB and Nrf2 activation in high-fat diet-induced renal injury is not absolutely understood. Quercetin, a natural product, has been reported to possess antitumor and anti-inflammatory effects. In this regard, this study attempted to prepare poly(d,l-lactide-co-glycolide-loaded gold nanoparticles precipitated with quercetin (GQ to investigate the anti-inflammatory and anti-oxidative stress effects in high-fat diet-induced kidney failure. For this study, C57BL/6 mice fed fat-rich fodder were used as the metabolic syndrome model to evaluate the protective effects of GQ on kidney injury and to determine whether TLR4/NF-κB and Nrf2 pathways were associated with the process. Moreover, histological examinations, enzyme-linked immunosorbent assay, Western blot, and basic blood tests and systemic inflammation-related indicators were used to investigate the inhibitory effects of GQ and underlying molecular mechanism by which it may reduce renal injury. Of note, podocyte

A Comparison of Pharmacological (Amitriptyline HCL) and Nonpharmacological (Cognitive-Behavioral) Therapies for Chronic Tension Headaches.

Science.gov (United States)

Holroyd, Kenneth A.; And Others

1991-01-01

Randomly assigned 41 recurrent tension headache sufferers to either cognitive-behavioral therapy or to amitriptyline therapy. Both therapies yielded clinically significant improvements in headache activity. In instances where differences in treatment effectiveness were observed, cognitive-behavioral therapy yielded somewhat more positive outcomes…

Pharmacological treatment of severely depressed patients: a meta-analysis comparing efficacy of mirtazapine and amitriptyline

NARCIS (Netherlands)

Kasper, S.; Zivkov, M.; Roes, K.C.B.; Pols, A.G.

1997-01-01

Efficacy data were available from 405 severely depressed patients (baseline 17-item Hamilton Rating Scale for Depression-HAMD scores ≤25) participating in randomized, double blind, amitriptyline-controlled studies of mirtazapine. Main efficacy variables were changes from baseline in the group mean

Soluble immune complexes shift the TLR-induced cytokine production of distinct polarized human macrophage subsets towards IL-10.

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Carmen A Ambarus

Full Text Available BACKGROUND: Costimulation of murine macrophages with immune complexes (ICs and TLR ligands leads to alternative activation. Studies on human myeloid cells, however, indicate that ICs induce an increased pro-inflammatory cytokine production. This study aimed to clarify the effect of ICs on the pro- versus anti-inflammatory profile of human polarized macrophages. MATERIALS AND METHODS: Monocytes isolated from peripheral blood of healthy donors were polarized for four days with IFN-γ, IL-4, IL-10, GM-CSF, M-CSF, or LPS, in the presence or absence of heat aggregated gamma-globulins (HAGGs. Phenotypic polarization markers were measured by flow cytometry. Polarized macrophages were stimulated with HAGGs or immobilized IgG alone or in combination with TLR ligands. TNF, IL-6, IL-10, IL-12, and IL-23 were measured by Luminex and/or RT-qPCR. RESULTS: HAGGs did not modulate the phenotypic polarization and the cytokine production of macrophages. However, HAGGs significantly altered the TLR-induced cytokine production of all polarized macrophage subsets, with the exception of MΦ(IL-4. In particular, HAGGs consistently enhanced the TLR-induced IL-10 production in both classically and alternatively polarized macrophages (M1 and M2. The effect of HAGGs on TNF and IL-6 production was less pronounced and depended on the polarization status, while IL-23p19 and IL-12p35 expression was not affected. In contrast with HAGGs, immobilized IgG induced a strong upregulation of not only IL-10, but also TNF and IL-6. CONCLUSION: HAGGs alone do not alter the phenotype and cytokine production of in vitro polarized human macrophages. In combination with TLR-ligands, however, HAGGs but not immobilized IgG shift the cytokine production of distinct macrophage subsets toward IL-10.

Fisetin Alleviates Lipopolysaccharide-Induced Acute Lung Injury via TLR4-Mediated NF-κB Signaling Pathway in Rats.

Science.gov (United States)

Feng, Guang; Jiang, Ze-Yu; Sun, Bo; Fu, Jie; Li, Tian-Zuo

2016-02-01

Acute lung injury (ALI), a common component of systemic inflammatory disease, is a life-threatening condition without many effective treatments. Fisetin, a natural flavonoid from fruits and vegetables, was reported to have wide pharmacological properties such as anti-inflammatory, antioxidant, and anticancer activities. The aim of this study was to detect the effects of fisetin on lipopolysaccharide (LPS)-induced acute lung injury and investigate the potential mechanism. Fisetin was injected (1, 2, and 4 mg/kg, i.v.) 30 min before LPS administration (5 mg/kg, i.v.). Our results showed that fisetin effectively reduced the inflammatory cytokine release and total protein in bronchoalveolar lavage fluids (BALF), decreased the lung wet/dry ratios, and obviously improved the pulmonary histology in LPS-induced ALI. Furthermore, fisetin inhibited LPS-induced increases of neutrophils and macrophage infiltration and attenuated MPO activity in lung tissues. Additionally, fisetin could significantly inhibit the Toll-like receptor 4 (TLR4) expression and the activation of NF-κB in lung tissues. Our data indicates that fisetin has a protective effect against LPS-induced ALI via suppression of TLR4-mediated NF-κB signaling pathways, and fisetin may be a promising candidate for LPS-induced ALI treatment.