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1.
Int Immunopharmacol ; 101(Pt A): 108295, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34735917

RESUMO

Toll-like receptors (TLRs) are among the players of inflammation during atherosclerosis. We assessed the effects of Eritoran, a TLR-4 antagonist, on lipopolysaccharide (LPS)-induced cytokines production by Peripheral Blood Mononuclear Cells (PBMCs) of patients with high-stenosis (HS) (n = 6) and healthy controls (HCs) (n = 6) co-cultured with Human Umbilical Vein Endothelial Cells (HUVECs). LPS stimulation significantly increased the levels of IL-6 (P = 0.007 and P = 0.005), TNF-α (P = 0.006 and P = 0.005), IL-2 (P = 0.007 and P = 0.002), IFN-γ (P = 0.006 and P = 0.003), IL-17A (P = 0.004 and P = 0.003), IL-17F (P = 0.005 and P = 0.003), IL-5 (P = 0.007 and P = 0.005), IL-13 (P = 0.006 and P = 0.005), IL-9 (P = 0.005 and P = 0.005) and IL-21 (P = 0.007 and P = 0.005) in HUVECs co-cultured with HC and HS PBMCs as compared with un-stimulated co-culture condition, respectively. Eritoran treatment (50 µg/mL and 100 µg/mL) significantly reduced the levels of LPS-induced IL-6 (P = 0.007 and P = 0.006; P = 0.007 and P = 0.007), TNF-α (P = 0.005 and P = 0.003; P = 0.007 and P = 0.005), IL-2 (P = 0.007 and P = 0.005; P = 0.005 and P = 0.004), IFN-γ (P = 0.007 and P = 0.005; P = 0.005 and P = 0.004), IL-17A (P = 0.005 and P = 0.002; P = 0.005 and P = 0.002), IL-17F (P = 0.006 and P = 0.006; P = 0.005 and P = 0.005), IL-5 (P = 0.007 and P = 0.006; P = 0.007 and P = 0.007), IL-9 (P = 0.005 and P = 0.005; P = 0.005 and P = 0.005) and IL-21 (P = 0.007 and P = 0.007; P = 0.005 and P = 0.005) in stimulated HUVECs co-cultured with HC and HS PBMCs, compared to un-treated condition, respectively. Our results demonstrate that attenuating effect of Eritoran on the inflammatory responses to LPS is higher in PBMCs of patients with high stenosis, suggesting its potential role in ameliorating inflammatory conditions in atherosclerosis.


Assuntos
Aterosclerose/imunologia , Citocinas/metabolismo , Dissacarídeos/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Fosfatos Açúcares/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Adulto , Aterosclerose/tratamento farmacológico , Estudos de Casos e Controles , Técnicas de Cocultura , Dissacarídeos/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/imunologia , Humanos , Interferon gama/metabolismo , Interleucina-17/metabolismo , Interleucina-2/metabolismo , Interleucina-6/metabolismo , Interleucina-9/metabolismo , Interleucinas/metabolismo , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Fosfatos Açúcares/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
2.
FASEB J ; 35(9): e21798, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34339064

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic threatens human species with mortality rate of roughly 2%. We can hardly predict the time of herd immunity against and end of COVID-19 with or without success of vaccine. One way to overcome the situation is to define what delineates disease severity and serves as a molecular target. The most successful analogy is found in BCR-ABL in chronic myeloid leukemia, which is the golden biomarker, and simultaneously, the most effective molecular target. We hypothesize that S100 calcium-binding protein A8 (S100A8) is one such molecule. The underlying evidence includes accumulating clinical information that S100A8 is upregulated in severe forms of COVID-19, pathological similarities of the affected lungs between COVID-19 and S100A8-induced acute respiratory distress syndrome (ARDS) model, homeostatic inflammation theory in which S100A8 is an endogenous ligand for endotoxin sensor Toll-like receptor 4/Myeloid differentiation protein-2 (TLR4/MD-2) and mediates hyper-inflammation even after elimination of endotoxin-producing extrinsic pathogens, analogous findings between COVID-19-associated ARDS and pre-metastatic lungs such as S100A8 upregulation, pulmonary recruitment of myeloid cells, increased vascular permeability, and activation coagulation cascade. A successful treatment in an animal COVID-19 model is given with a reagent capable of abrogating interaction between S100A8/S100A9 and TLR4. In this paper, we try to verify our hypothesis that S100A8 governs COVID-19-associated ARDS.


Assuntos
COVID-19/complicações , Calgranulina A/fisiologia , Síndrome da Liberação de Citocina/etiologia , Inflamação/etiologia , Pandemias , Síndrome do Desconforto Respiratório/etiologia , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/fisiologia , Animais , Antivirais/farmacologia , COVID-19/genética , COVID-19/patologia , Calgranulina A/sangue , Calgranulina A/genética , Quimiocina CXCL11/sangue , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/patologia , Dissacarídeos/farmacologia , Dissacarídeos/uso terapêutico , Modelos Animais de Doenças , Descoberta de Drogas , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Humanos , Inflamação/genética , Inflamação/patologia , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Antígeno 96 de Linfócito/fisiologia , Macaca mulatta , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Mutação , Síndrome do Desconforto Respiratório/genética , Síndrome do Desconforto Respiratório/metabolismo , Especificidade da Espécie , Fosfatos Açúcares/farmacologia , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/fisiologia , Regulação para Cima , Internalização do Vírus
3.
Cell Death Dis ; 7: e2234, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27228349

RESUMO

Toll-like receptors (TLRs) are a family of pattern recognition receptors involved in cardiovascular diseases. Notably, numerous studies have demonstrated that TLR4 activates the expression of several of pro-inflammatory cytokine genes that play pivotal roles in myocardial inflammation, particularly myocarditis, myocardial infarction, ischemia-reperfusion injury, and heart failure. In addition, TLR4 is an emerging target for anti-inflammatory therapies. Given the significance of TLR4, it would be useful to summarize the current literature on the molecular mechanisms and roles of TLR4 in myocardial inflammation. Thus, in this review, we first introduce the basic knowledge of the TLR4 gene and describe the activation and signaling pathways of TLR4 in myocardial inflammation. Moreover, we highlight the recent progress of research on the involvement of TLR4 in myocardial inflammation. The information reviewed here may be useful to further experimental research and to increase the potential of TLR4 as a therapeutic target.


Assuntos
Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/imunologia , Infarto do Miocárdio/imunologia , Miocardite/imunologia , Traumatismo por Reperfusão/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Ensaios Clínicos como Assunto , Dissacarídeos/uso terapêutico , Folistatina/uso terapêutico , Regulação da Expressão Gênica , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Humanos , Metformina/uso terapêutico , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miocardite/tratamento farmacológico , Miocardite/genética , Miocardite/patologia , Miocárdio/imunologia , Miocárdio/metabolismo , Miocárdio/patologia , NF-kappa B/genética , NF-kappa B/imunologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética
4.
Crit Care Med ; 44(8): 1461-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26992066

RESUMO

OBJECTIVES: To describe the quality of life among sepsis survivors. DESIGN: Secondary analyses of two international, randomized clinical trials (A Controlled Comparison of Eritoran and placebo in patients with Severe Sepsis [derivation cohort] and PROWESS-SHOCK [validation cohort]). SETTING: ICUs in North and South America, Europe, Africa, Asia, and Australia. PATIENTS: Adults with severe sepsis. We analyzed only patients who were functional and living at home without help before sepsis hospitalization (n = 1,143 and 987 from A Controlled Comparison of Eritoran and placebo in patients with Severe Sepsis and PROWESS-SHOCK, respectively). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In A Controlled Comparison of Eritoran and placebo in patients with Severe Sepsis and PROWESS-SHOCK, the average age of patients living at home independently was 63 and 61 years; 400 (34.9%) and 298 (30.2%) died by 6 months. In A Controlled Comparison of Eritoran and placebo in patients with Severe Sepsis, 580 patients had a quality of life measured using EQ-5D at 6 months. Of these, 41.6% could not live independently (22.7% were home but required help, 5.1% were in nursing home or rehabilitation facilities, and 5.3% were in acute care hospitals). Poor quality of life at 6 months, as evidenced by problems in mobility, usual activities, and self-care domains were reported in 37.4%, 43.7%, and 20.5%, respectively, and the high incidence of poor quality of life was also seen in patients in PROWESS-SHOCK. Over 45% of patients with mobility and self-care problems at 6 months in A Controlled Comparison of Eritoran and placebo in patients with Severe Sepsis died or reported persistent problems at 1 year. CONCLUSIONS: Among individuals enrolled in a clinical trial who lived independently prior to severe sepsis, one third had died and of those who survived, a further one third had not returned to independent living by 6 months. Both mortality and quality of life should be considered when designing new interventions and considering endpoints for sepsis trials.


Assuntos
Qualidade de Vida , Sepse/mortalidade , Sobreviventes/estatística & dados numéricos , Atividades Cotidianas , Adulto , Idoso , Comorbidade , Dissacarídeos/uso terapêutico , Feminino , Humanos , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Sepse/tratamento farmacológico , Índice de Gravidade de Doença , Fosfatos Açúcares/uso terapêutico
5.
Mediators Inflamm ; 2014: 643525, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25165412

RESUMO

PURPOSE: We investigated the effect of eritoran, a Toll-like receptor 4 antagonist, on retinochoroidal inflammatory damage in an endotoxin-induced inflammatory rat model. METHODS: Endotoxin-induced inflammatory model was obtained by intraperitoneal injection of 1.5 mg/kg lipopolysaccharide (LPS). Group 1 had control rats; in groups 2-3 LPS and 0.5 mg/kg sterile saline were injected; and in groups 4-5 LPS and 0.5 mg/kg eritoran were injected. Blood samples were taken and eyes were enucleated after 12 hours (h) (groups 2 and 4) or 24 hours (Groups 3 and 5). Tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA) levels in the serum and retinochoroidal tissue and nuclear factor kappa-B (NFκB) levels in retinochoroidal tissue were determined. Histopathological examination was performed and retinochoroidal changes were scored. RESULTS: Eritoran treatment resulted in lower levels of TNF-α, MDA, and NFκB after 12 h which became significant after 24 h. Serum TNF-α and retinochoroidal tissue NFκB levels were similar to control animals at the 24th h of the study. Eritoran significantly reversed histopathological damage after 24 h. CONCLUSIONS: Eritoran treatment resulted in less inflammatory damage in terms of serum and retinochoroidal tissue parameters.


Assuntos
Dissacarídeos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/toxicidade , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Inflamação/metabolismo , Masculino , Malondialdeído/sangue , Malondialdeído/metabolismo , NF-kappa B/sangue , NF-kappa B/metabolismo , Ratos , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
6.
Front Biosci (Landmark Ed) ; 19(6): 904-15, 2014 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-24896325

RESUMO

Sepsis continues to be a leading cause of intensive care unit (ICU) death. Gram-negative bacteria are among the most important pathogens of sepsis and their LPS content is regarded to be an important stimulator that elicits the systemic inflammatory reaction. MD-2 is a small secreted glycoprotein that can bind to both the hydrophobic portion of LPS and to the extracellular domain of TLR4. The interaction between MD-2 and LPS bridges the two TLR4 molecules and induces the dimerization of LPS-MD-2-TLR4, which forms the structural basis for biological functions of TLR4/MD-2 complex. Due to its essential role in mediating the interaction between LPS and TLR4, MD-2 has been extensively explored as a therapeutic target for treatment of inflammatory disorders such as sepsis. Eritoran is a synthetic tetraacylated lipid A that binds directly to MD-2 and antagonizes LPS binding to the same site. Although eritoran showed positive results in phase I and phase II clinical trials of severe sepsis, a phase III clinical study for severe sepsis has failed. More effective therapeutic strategies are in need to treat this devastating clinical disorder.


Assuntos
Dissacarídeos/uso terapêutico , Antígeno 96 de Linfócito/antagonistas & inibidores , Terapia de Alvo Molecular/métodos , Sepse/tratamento farmacológico , Fosfatos Açúcares/uso terapêutico , Humanos , Lipopolissacarídeos/metabolismo , Antígeno 96 de Linfócito/metabolismo , Modelos Biológicos , Ligação Proteica/efeitos dos fármacos , Sepse/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
7.
J Surg Res ; 184(2): e17-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23777984

RESUMO

BACKGROUND: Severe injury and associated hemorrhagic shock lead to an inflammatory response and subsequent increased tissue damage. Numerous reports have shown that injury-induced inflammation and the associated end-organ damage is driven by Toll-like receptor 4 (TLR4) activation via damage-associated molecular patterns. We examined the effectiveness of Eritoran tetrasodium (E5564), an inhibitor of TLR4 function, in reducing inflammation induced during hemorrhagic shock with resuscitation (HS/R) or after peripheral tissue injury (bilateral femur fracture, BFF). MATERIAL AND METHODS: Mice underwent HS/R or BFF with or without injection of Eritoran (5 mg/kg body weight) or vehicle control given before, both before and after, or only after HS/R or BFF. Mice were sacrificed after 6 h and plasma and tissue cytokines, liver damage (histology; aspartate aminotransferase/alanine aminotransferase), and inflammation (NF-κB) and gut permeability were assessed. RESULTS: In HS/R Eritoran significantly reduced liver damage (values ± SEM: alanine aminotransferase 9910 ± 3680 U/L versus 1239 ± 327 U/L and aspartate aminotransferase 5863 ± 2000 U/L versus 1246 ± 243 U/L, P < 0.01) at 6 h compared with control when given just before HS and again just prior to resuscitation. Eritoran administration also led to lower IL-6 levels in plasma and liver and less NF-κB activation in liver. Increases in gut barrier permeability induced by HS/R were also prevented with Eritoran. Eritoran similarly diminished BFF-mediated systemic inflammatory responses. CONCLUSION: These data suggest Eritoran can inhibit tissue damage and inflammation induced via TLR4/myeloid differentiation factor 2 signaling from damage-associated molecular patterns released during HS/R or BFF. Eritoran may represent a promising therapeutic for trauma patients to prevent multiple organ failure.


Assuntos
Dissacarídeos/uso terapêutico , Inflamação/prevenção & controle , Choque Hemorrágico/complicações , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Ferimentos e Lesões/complicações , Animais , Fraturas do Fêmur/complicações , Fraturas do Fêmur/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Antígeno 96 de Linfócito/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , NF-kappa B/metabolismo , Choque Hemorrágico/metabolismo , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismo , Transaminases/metabolismo , Ferimentos e Lesões/metabolismo
8.
Nature ; 497(7450): 498-502, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23636320

RESUMO

There is a pressing need to develop alternatives to annual influenza vaccines and antiviral agents licensed for mitigating influenza infection. Previous studies reported that acute lung injury caused by chemical or microbial insults is secondary to the generation of host-derived, oxidized phospholipid that potently stimulates Toll-like receptor 4 (TLR4)-dependent inflammation. Subsequently, we reported that Tlr4(-/-) mice are highly refractory to influenza-induced lethality, and proposed that therapeutic antagonism of TLR4 signalling would protect against influenza-induced acute lung injury. Here we report that therapeutic administration of Eritoran (also known as E5564)-a potent, well-tolerated, synthetic TLR4 antagonist-blocks influenza-induced lethality in mice, as well as lung pathology, clinical symptoms, cytokine and oxidized phospholipid expression, and decreases viral titres. CD14 and TLR2 are also required for Eritoran-mediated protection, and CD14 directly binds Eritoran and inhibits ligand binding to MD2. Thus, Eritoran blockade of TLR signalling represents a novel therapeutic approach for inflammation associated with influenza, and possibly other infections.


Assuntos
Antivirais/farmacologia , Dissacarídeos/farmacologia , Dissacarídeos/uso terapêutico , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Infecções por Orthomyxoviridae/tratamento farmacológico , Fosfatos Açúcares/farmacologia , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Lesão Pulmonar Aguda/complicações , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/prevenção & controle , Animais , Antivirais/uso terapêutico , Citocinas/genética , Citocinas/imunologia , Dissacarídeos/metabolismo , Feminino , Ligantes , Receptores de Lipopolissacarídeos/metabolismo , Antígeno 96 de Linfócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Fosfatos Açúcares/metabolismo , Análise de Sobrevida , Fatores de Tempo , Receptor 2 Toll-Like/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/imunologia
10.
JAMA ; 309(11): 1154-62, 2013 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-23512062

RESUMO

IMPORTANCE: Eritoran is a synthetic lipid A antagonist that blocks lipopolysaccharide (LPS) from binding at the cell surface MD2-TLR4 receptor. LPS is a major component of the outer membrane of gram-negative bacteria and is a potent activator of the acute inflammatory response. OBJECTIVE: To determine if eritoran, a TLR4 antagonist, would significantly reduce sepsis-induced mortality. DESIGN, SETTING, AND PARTICIPANTS: We performed a randomized, double-blind, placebo-controlled, multinational phase 3 trial in 197 intensive care units. Patients were enrolled from June 2006 to September 2010 and final follow-up was completed in September 2011. INTERVENTIONS: Patients with severe sepsis (n = 1961) were randomized and treated within 12 hours of onset of first organ dysfunction in a 2:1 ratio with a 6-day course of either eritoran tetrasodium (105 mg total) or placebo, with n = 1304 and n = 657 patients, respectively. MAIN OUTCOME MEASURES: The primary end point was 28-day all-cause mortality. The secondary end points were all-cause mortality at 3, 6, and 12 months after beginning treatment. RESULTS: Baseline characteristics of the 2 study groups were similar. In the modified intent-to-treat analysis (randomized patients who received at least 1 dose) there was no significant difference in the primary end point of 28-day all-cause mortality with 28.1% (366/1304) in the eritoran group vs 26.9% (177/657) in the placebo group (P = .59; hazard ratio, 1.05; 95% CI, 0.88-1.26; difference in mortality rate, -1.1; 95% CI, -5.3 to 3.1) or in the key secondary end point of 1-year all-cause mortality with 44.1% (290/657) in the eritoran group vs 43.3% (565/1304) in the placebo group, Kaplan-Meier analysis of time to death by 1 year, P = .79 (hazard ratio, 0.98; 0.85-1.13). No significant differences were observed in any of the prespecified subgroups. Adverse events, including secondary infection rates, did not differ between study groups. CONCLUSIONS AND RELEVANCE: Among patients with severe sepsis, the use of eritoran, compared with placebo, did not result in reduced 28-day mortality. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00334828.


Assuntos
Dissacarídeos/uso terapêutico , Sepse/tratamento farmacológico , Sepse/mortalidade , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Índice de Gravidade de Doença , Adulto Jovem
11.
Pharmacol Ther ; 133(3): 291-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22119168

RESUMO

Lipopolysaccharide (LPS), an endotoxin of Gram-negative bacteria, activates the innate immunity system through a receptor complex of myeloid differentiation 2 (MD-2) and toll-like receptor 4 (TLR4). MD-2 directly recognizes the lipid A domain of LPS, which triggers MD-2/TLR4-mediated cellular response aimed at eliminating the invaded pathogen. However, excess production of inflammatory mediators is harmful to host tissue and this can cause septic death in extreme cases. MD-2 represents an attractive therapeutic target of inflammatory and immune diseases in human. In particular, eritoran is a synthetic tetraacylated lipid A that binds directly to MD-2 and antagonizes LPS binding to the same site, and it ameliorates various inflammatory conditions due to infection or sterile organ injury. In this review, we outline the recent advances in the structure biology of ligand interaction with MD-2/TLR4, and highlight the MD-2-directed LPS antagonists, which are natural and synthetic chemicals, under development to treat inflammatory diseases.


Assuntos
Inflamação/imunologia , Antígeno 96 de Linfócito/imunologia , Animais , Anti-Inflamatórios/uso terapêutico , Dissacarídeos/uso terapêutico , Glicolipídeos/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Lipídeo A/análogos & derivados , Lipídeo A/uso terapêutico , Lipopolissacarídeos/imunologia , Antígeno 96 de Linfócito/agonistas , Antígeno 96 de Linfócito/antagonistas & inibidores , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/imunologia
13.
Shock ; 36(6): 613-20, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22089127

RESUMO

Severe sepsis and septic shock are often accompanied by acute cardiovascular depression. Lipopolysaccharide (LPS) signaling via Toll-like receptor 4 (TLR4) can induce septic organ dysfunction. The aim of this study was to elucidate the in vivo impact of pharmacological TLR4 antagonism on LPS-induced cardiovascular depression using eritoran tetrasodium (E5564). To simulate sepsis, C3H/HeN mice were challenged i.p. with 2 mg/kg body weight LPS. With the intent to antagonize the LPS effects, eritoran was administered i.v. (4 mg/kg body weight). Physical activity, peripheral blood pressure, and heart frequency were recorded before and after LPS and eritoran injection. In addition, intracardiac hemodynamic parameters were analyzed with a pressure conductance catheter. After 2 and 6 h of LPS stimulation ± eritoran treatment, the hearts and aortae were harvested, and TLR as well as inflammatory mediator expression was measured using reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Lipopolysaccharide significantly decreased arterial blood pressure over time. Administration of eritoran partially prevented the LPS-dependent reduction in blood pressure and preserved cardiac function. In addition, LPS increased the expression of CD14 and TLR2 in cardiac and aortic tissue. In aortic tissue, eritoran attenuated this increase, whereas no significant reduction was observed in the heart. Furthermore, cardiac and aortic inducible nitric oxide synthetase mRNA levels were significantly increased 6 h after LPS application. This effect was reduced in the presence of eritoran. In summary, the beneficial influence of eritoran on cardiovascular function in vivo seems to rely mainly on reduction of LPS-induced inducible nitric oxide synthetase expression as well as on attenuated cytokine expression in the vascular wall.


Assuntos
Dissacarídeos/uso terapêutico , Endotoxemia/tratamento farmacológico , Sepse/tratamento farmacológico , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Endotoxemia/induzido quimicamente , Feminino , Lipopolissacarídeos/toxicidade , Masculino , Camundongos
15.
Shock ; 36(4): 327-31, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21701421

RESUMO

Disease severity varies widely in patients with severe sepsis. Eritoran tetrasodium (E5564), a TLR4 antagonist, blocks the binding of endotoxin and is being evaluated as a novel therapy for severe sepsis. This analysis aimed to assess the efficacy of eritoran based on severity of illness and similar effects in other recent sepsis trials. Prospective covariates from a randomized, double-blind, placebo-controlled, phase 2 trial were analyzed for treatment interaction measured by 28-day mortality. Five statistical interaction methodologies were used. The modified intent-to-treat population (n = 292), all-cause 28-day mortality was as follows: placebo, 33.3% (32/96); eritoran 45 mg/105 mg, 29.6% (58/196). Logistic regression analysis identified Acute Physiology and Chronic Health Evaluation II scores, predicted-risk-of-mortality scores, IL-6, age, sex, race, and eritoran use as associated with survival. Significant treatment interactions were observed (eritoran vs. placebo) for baseline covariates: Acute Physiology and Chronic Health Evaluation II (P = 0.035), predicted-risk-of-mortality scores (P = 0.008), number of organ failures (P = 0.079), international normalized ratio (P = 0.05), and acute physiology score (P = 0.039). I analysis showed that 38% of the total eritoran treatment variance was explained by the severity-of-illness heterogeneity rather than by chance. No interactions observed with other variables. Consistent with the finding in this eritoran trial, other sepsis trials (IL-1 receptor antagonist, TNFsr-p55, antithrombin, drotrecogin alfa-activated) also demonstrated significant treatment by severity interaction. Potential survival benefits of eritoran in severe sepsis patients were associated with high severity of illness. These findings were used to design a phase 3 trial. Similar treatment by severity-of-illness interaction was found in most recent sepsis trials.


Assuntos
Dissacarídeos/uso terapêutico , Sepse/tratamento farmacológico , Sepse/patologia , Fosfatos Açúcares/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Interleucina-6/sangue , Masculino , Sepse/sangue , Resultado do Tratamento
16.
Eur J Heart Fail ; 13(6): 602-10, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21613426

RESUMO

AIMS: Toll-like receptor 4 (TLR4) recognizes lipopolysaccharides and endogenous ligands released after organ injury. Deficiency of TLR4 attenuates the development of left ventricular hypertrophy after transverse aortic constriction (TAC) in mice. We hypothesized that application of the TLR4 antagonist eritoran may also reduce cardiac hypertrophy after TAC surgery. METHODS AND RESULTS: A catheter was implanted into the jugular vein of C57BL/6 mice to allow repeated administration of eritoran (5 mg/kg body weight) or placebo. Three days after TAC or sham surgery, heart weights were determined and cardiac tissue underwent mRNA and protein quantification. The TAC placebo group exhibited a significant increase in left ventricular weight, left ventricular weight/tibia length, and left ventricular/body weight ratio compared with the sham and TAC eritoran groups. Natriuretic peptide mRNA was elevated significantly only in TAC placebo mice. Transverse aortic constriction surgery led to a distinct increase in interleukin (IL)-1ß and IL-6 mRNA and protein expression in the placebo but not the eritoran group. In contrast, IL-10 was significantly increased in both eritoran groups independent from TAC. Matrix metalloproteinase zymographic activity was highest in TAC placebo animals. CONCLUSION: Application of the TLR4 antagonist eritoran attenuates the development of cardiac hypertrophy possibly by a reduction in inflammatory and increase in anti-inflammatory cytokines.


Assuntos
Cardiomegalia/tratamento farmacológico , Dissacarídeos/uso terapêutico , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Cardiomegalia/metabolismo , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Interleucinas/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo Natriurético Encefálico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Expert Opin Drug Metab Toxicol ; 7(4): 479-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21323610

RESUMO

INTRODUCTION: Sepsis remains a leading cause of death worldwide. Despite years of extensive research, effective drugs that inhibit the pro-inflammatory effects of lipopolysaccharide (LPS) and improve outcome when added to conventional sepsis treatments are lacking. Eritoran tetrasodium (E5564) is a promising candidate therapy for sepsis belonging to a new class of such drugs which inhibit LPS-induced inflammation by blocking toll-like receptor 4. AREAS COVERED: This review focuses on the rationale for the use of eritoran tetrasodium in sepsis as well as on its pharmacokinetics, pharmacodynamics, efficacy and safety. Preclinical and clinical studies from a MEDLINE/PubMed literature search in August 2010 with the search terms 'eritoran' and 'E5564' are discussed. EXPERT OPINION: Preclinical in vitro and in vivo studies of eritoran tetrasodium indicate it can limit excessive inflammatory mediator release associated with LPS and improve survival in sepsis models. While early clinical results are promising, its efficacy and safety for treating patients with sepsis are currently under investigation. Even if the ongoing Phase III clinical trial enrolling patients with severe sepsis and increased risk of death shows benefit from eritoran, questions remain and confirmatory studies would be necessary to define its clinical usage.


Assuntos
Dissacarídeos/uso terapêutico , Relação Dose-Resposta a Droga , Sepse/tratamento farmacológico , Fosfatos Açúcares/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Ensaios Clínicos como Assunto , Dissacarídeos/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Lipopolissacarídeos/farmacologia , Sepse/mortalidade , Fosfatos Açúcares/farmacocinética , Receptor 4 Toll-Like/antagonistas & inibidores
18.
Eur J Cardiothorac Surg ; 39(4): 451-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20663682

RESUMO

Cardiac surgery with cardiopulmonary bypass provokes a systemic inflammatory response syndrome caused by the surgical trauma itself, blood contact with the non-physiological surfaces of the extracorporeal circuit, endotoxemia, and ischemia. The role of endotoxin in the inflammatory response syndrome has been well investigated. In this report, we reviewed recent advances in the understanding of the pathophysiology of the endotoxin release during cardiopulmonary bypass and the possible therapeutic strategies aimed to reduce the endotoxin release or to counteract the inflammatory effects of endotoxin. Although many different strategies to detoxify endotoxins were evaluated, none of them were able to show statistically significant differences in clinical outcome.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Endotoxinas/metabolismo , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Corticosteroides/uso terapêutico , Fosfatase Alcalina/fisiologia , Anti-Infecciosos/uso terapêutico , Anticorpos/fisiologia , Citocinas/fisiologia , Dissacarídeos/uso terapêutico , Endotoxinas/imunologia , Hemoperfusão/métodos , Humanos , Hipotermia Induzida , Ketanserina/uso terapêutico , Antagonistas da Serotonina/uso terapêutico , Fosfatos Açúcares/uso terapêutico , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Síndrome de Resposta Inflamatória Sistêmica/metabolismo , Taurina/análogos & derivados , Taurina/uso terapêutico , Tiadiazinas/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores
19.
Transplant Proc ; 42(5): 1539-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20620471

RESUMO

BACKGROUND: Ischemia-reperfusion injury (I/R) has a negative effect on renal allograft survival. Using a rat model of kidney IR injury, we demonstrated inhibition of Toll-like receptor (TLR) 4 with erotoran may shed new light on I/R therapy. METHODS: All 44 Fisher rats were anesthetized with ethrane. Animals were randomly divided into the S group (sham, n = 11) that received only right kidney nephrectomy or the I/R group of right kidney nephrectomy and ichemia for 40 minutes by clamping of left renal artery (n = 11). In addition, the E group (Eritoran, n = 11) and the V group (vehicle, n = 11) received eritoran (5 mg x kg(-1)) and vehicle pretreatment, respectively. Analysis of renal histology, function, cytokine/chemokine production, as well as animal mortality was performed in parallel groups by ribonuclease protection assay (RPA). RESULTS: At 24 hours, the creatinine value 1.49 +/- 0.2 mg/dL in the eritoran group was significantly lower than untreated controls (2.17 +/- 0.4 mg/dL). Histological findings showed tubular loss and morphological stutus as well as animal survival post-I/R injury compared to vehicle-treated rats; the difference between the S versus E groups was significant. Eritoran administration significantly attenuated monocyte infiltration into the kidney. RPA assays showed the following fold increase over sham normalized to that of GAPDH mRNA expression of tumor necrosis factor-alpha (4.67 +/- 1.52 vs 1.37 +/- 0.05), interleukin (IL)-1beta (5.11 +/- 1.17 vs 1.92 +/- 0.27), IL-6 (4.20 +/- 0.29 vs 1.21 +/- 0.37) and monocyte chemoattractant protein-1 (8.77 +/- 1.24 vs 2.57 +/- 1.59). GAPDH was markedly reduced by eritoran treatment (eritoran vs vehicle group). CONCLUSION: These data demonstrated that inhibition of TLR4 with eritoran reduced I/R-related inflammatory responses and improved the course of kidney I/R injury.


Assuntos
Dissacarídeos/uso terapêutico , Rim/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Fosfatos Açúcares/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Quimiocinas/genética , Creatinina/sangue , Citocinas/genética , Modelos Animais de Doenças , Rim/irrigação sanguínea , Rim/patologia , Testes de Função Renal , Masculino , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos F344 , Artéria Renal/patologia , Artéria Renal/fisiologia , Circulação Renal/efeitos dos fármacos
20.
Mediators Inflamm ; 2010: 568396, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20396414

RESUMO

Despite a decrease in mortality over the last decade, sepsis remains the tenth leading causes of death in western countries and one of the most common cause of death in intensive care units. The recent discovery of Toll-like receptors and their downstream signalling pathways allowed us to better understand the pathophysiology of sepsis-related disorders. Particular attention has been paid to Toll-like receptor 4, the receptor for Gram-negative bacteria outer membrane lipopolysaccharide or endotoxin. Since most of the clinical trial targeting single inflammatory cytokine in the treatment of sepsis failed, therapeutic targeting of Toll-like receptor 4, because of its central role, looks promising. The purpose of this paper is to focus on the recent data of various drugs targeting TLR4 expression and pathway and their potential role as adjunctive therapy in severe sepsis and septic shock.


Assuntos
Sepse/tratamento farmacológico , Receptor 4 Toll-Like/uso terapêutico , Analgésicos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Animais , Anticorpos/imunologia , Antirreumáticos/uso terapêutico , Cloroquina/uso terapêutico , Colecalciferol/análogos & derivados , Colecalciferol/uso terapêutico , Dissacarídeos/uso terapêutico , Estimulantes Ganglionares/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ketamina/uso terapêutico , Antígeno 96 de Linfócito/imunologia , Nicotina/uso terapêutico , Sepse/imunologia , Fosfatos Açúcares/uso terapêutico , Sulfonamidas/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/imunologia
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