RESUMO
PURPOSE: Myocardial ischemia/reperfusion (Ml/R) injury is a leading cause of damage in cardiac tissues, with high rates of mortality and disability. Biochanin A (BCA) is a main constituent of Trifolium pratense L. This study was intended to explore the effect of BCA on Ml/R injury and explore the potential mechanism. METHODS: In vivo MI/R injury was established by transient coronary ligation in Sprague-Dawley rats. Triphenyltetrazolium chloride staining (TTC) was used to measure myocardial infarct size. ELISA assay was employed to evaluate the levels of myocardial enzyme and inflammatory cytokines. Western blot assay was conducted to detect related protein levels in myocardial tissues. RESULTS: BCA significantly ameliorated myocardial infarction area, reduced the release of myocardial enzyme levels including aspartate transaminase (AST), creatine kinase (CK-MB) and lactic dehydrogenase (LDH). It also decreased the production of inflammatory cytokines (IL-1ß, IL-18, IL-6 and TNF-α) in serum of Ml/R rats. Further mechanism studies demonstrated that BCA inhibited inflammatory reaction through blocking TLR4/NF-kB/NLRP3 signaling pathway. CONCLUSION: The present study is the first evidence demonstrating that BCA attenuated Ml/R injury through suppressing TLR4/NF-kB/NLRP3 signaling pathway-mediated anti-inflammation pathway.
Assuntos
Cardiotônicos/farmacologia , Genisteína/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NF-kappa B/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Aspartato Aminotransferases/sangue , Western Blotting , Creatina Quinase/sangue , Citocinas/sangue , Lactato Desidrogenases/sangue , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos Sprague-Dawley , Valores de Referência , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismoRESUMO
Abstract Purpose: Myocardial ischemia/reperfusion (Ml/R) injury is a leading cause of damage in cardiac tissues, with high rates of mortality and disability. Biochanin A (BCA) is a main constituent of Trifolium pratense L. This study was intended to explore the effect of BCA on Ml/R injury and explore the potential mechanism. Methods: In vivo MI/R injury was established by transient coronary ligation in Sprague-Dawley rats. Triphenyltetrazolium chloride staining (TTC) was used to measure myocardial infarct size. ELISA assay was employed to evaluate the levels of myocardial enzyme and inflammatory cytokines. Western blot assay was conducted to detect related protein levels in myocardial tissues. Results: BCA significantly ameliorated myocardial infarction area, reduced the release of myocardial enzyme levels including aspartate transaminase (AST), creatine kinase (CK-MB) and lactic dehydrogenase (LDH). It also decreased the production of inflammatory cytokines (IL-1β, IL-18, IL-6 and TNF-α) in serum of Ml/R rats. Further mechanism studies demonstrated that BCA inhibited inflammatory reaction through blocking TLR4/NF-kB/NLRP3 signaling pathway. Conclusion: The present study is the first evidence demonstrating that BCA attenuated Ml/R injury through suppressing TLR4/NF-kB/NLRP3 signaling pathway-mediated anti-inflammation pathway.
Assuntos
Animais , Masculino , Cardiotônicos/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NF-kappa B/efeitos dos fármacos , Genisteína/farmacologia , Receptor 4 Toll-Like/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Aspartato Aminotransferases/sangue , Valores de Referência , Traumatismo por Reperfusão Miocárdica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Western Blotting , Reprodutibilidade dos Testes , Citocinas/sangue , NF-kappa B/metabolismo , Ratos Sprague-Dawley , Creatina Quinase/sangue , Lactato Desidrogenases/sangue , Receptor 4 Toll-Like/metabolismo , Anti-Inflamatórios/farmacologiaRESUMO
Purpose: In view of the principal role of Toll-like receptor 4 (TLR4) in mediating sterile inflammatory response contributing to osteoarthritis (OA) pathogenesis, we used lipopolysaccharide (LPS), a known TLR4 activator, to clarify whether modulation of TLR4 contributed to the protective actions of intra-articular administration of curcumin in a classical rat OA model surgically induced by anterior cruciate ligament transection (ACLT). Methods: The rats underwent ACLT and received 50μl of curcumin at the concentration of 1 mg mL-1and 10 μg LPS by intra-articular injection once a week for 8 weeks. Morphological changes of the cartilage and synovial tissues were observed. Apoptotic chondrocytes were detected using TUNEL assay. The concentrations of IL-1β and TNF-ɑ in synovial fluid were determined using ELISA kits. The mRNA and protein expression levels of TLR4 and NF-κB p65 were detected by real-time PCR and Western blotting, respectively. Results: Intra-articular administration of curcumin significantly improved articular cartilage injury, suppressed synovial inflammation and down-regulated the overexpression of TLR4 and its downstream NF-κB caused by LPS-induced TLR4 activation in rat osteoarthritic knees. Conclusion: The data suggested that the inhibition of TLR4 signal might be an important mechanism underlying a protective effect of local curcumin administration on OA.(AU)
Assuntos
Animais , Masculino , Ratos , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Osteoartrite/prevenção & controle , Lipopolissacarídeos/análise , Lipopolissacarídeos/uso terapêutico , Curcuma/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Cartilagem/efeitos dos fármacos , Líquido Sinovial/efeitos dos fármacos , ChinaRESUMO
PURPOSE: In view of the principal role of Toll-like receptor 4 (TLR4) in mediating sterile inflammatory response contributing to osteoarthritis (OA) pathogenesis, we used lipopolysaccharide (LPS), a known TLR4 activator, to clarify whether modulation of TLR4 contributed to the protective actions of intra-articular administration of curcumin in a classical rat OA model surgically induced by anterior cruciate ligament transection (ACLT). METHODS: The rats underwent ACLT and received 50µl of curcumin at the concentration of 1 mg mL-1 and 10 µg LPS by intra-articular injection once a week for 8 weeks. Morphological changes of the cartilage and synovial tissues were observed. Apoptotic chondrocytes were detected using TUNEL assay. The concentrations of IL-1ß and TNF-É in synovial fluid were determined using ELISA kits. The mRNA and protein expression levels of TLR4 and NF-κB p65 were detected by real-time PCR and Western blotting, respectively. RESULTS: Intra-articular administration of curcumin significantly improved articular cartilage injury, suppressed synovial inflammation and down-regulated the overexpression of TLR4 and its downstream NF-κB caused by LPS-induced TLR4 activation in rat osteoarthritic knees. CONCLUSION: The data suggested that the inhibition of TLR4 signal might be an important mechanism underlying a protective effect of local curcumin administration on OA.
Assuntos
Ligamento Cruzado Anterior/cirurgia , Curcumina/farmacologia , Osteoartrite/prevenção & controle , Receptor 4 Toll-Like/metabolismo , Animais , Ligamento Cruzado Anterior/patologia , Western Blotting , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Injeções Intra-Articulares , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Masculino , NF-kappa B/metabolismo , Osteoartrite/induzido quimicamente , Osteoartrite/metabolismo , Reação em Cadeia da Polimerase , Ratos , Receptor 4 Toll-Like/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Acute lung injury (ALI) is a serious clinical syndrome with a high rate of mortality. The activation of inflammation is well-recognized as a vital factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI. Therefore, suppression of the inflammatory response could be an ideal strategy to prevent ALI. Epigallocatechin-3-gallate (EGCG), mainly from green tea, has been shown to have an anti-inflammatory effect. The aim of the study was to explore whether EGCG alleviates inflammation in sepsis-related ALI. Male BALB/C mice were treated with EGCG (10 mg/kg) intraperitoneally (ip) 1 h before LPS injection (10 mg/kg, ip). The results showed that EGCG attenuated LPS-induced ALI as it decreased the changes in blood gases and reduced the histological lesions, wet-to-dry weight ratios, and myeloperoxidase (MPO) activity. In addition, EGCG significantly decreased the expression of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 in the lung, serum, and bronchoalveolar lavage fluid, and alleviated the expression of TLR-4, MyD88, TRIF, and p-p65 in the lung tissue. In addition, it increased the expression of IκB-α and had no influence on the expression of p65. Collectively, these results demonstrated the protective effects of EGCG against LPS-induced ALI in mice through its anti-inflammatory effect that may be attributed to the suppression of the activation of TLR 4-dependent NF-κB signaling pathways.
Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Catequina/análogos & derivados , NF-kappa B/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Catequina/administração & dosagem , Modelos Animais de Doenças , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacosRESUMO
Abstract Purpose In view of the principal role of Toll-like receptor 4 (TLR4) in mediating sterile inflammatory response contributing to osteoarthritis (OA) pathogenesis, we used lipopolysaccharide (LPS), a known TLR4 activator, to clarify whether modulation of TLR4 contributed to the protective actions of intra-articular administration of curcumin in a classical rat OA model surgically induced by anterior cruciate ligament transection (ACLT). Methods The rats underwent ACLT and received 50μl of curcumin at the concentration of 1 mg mL-1 and 10 μg LPS by intra-articular injection once a week for 8 weeks. Morphological changes of the cartilage and synovial tissues were observed. Apoptotic chondrocytes were detected using TUNEL assay. The concentrations of IL-1β and TNF-ɑ in synovial fluid were determined using ELISA kits. The mRNA and protein expression levels of TLR4 and NF-κB p65 were detected by real-time PCR and Western blotting, respectively. Results Intra-articular administration of curcumin significantly improved articular cartilage injury, suppressed synovial inflammation and down-regulated the overexpression of TLR4 and its downstream NF-κB caused by LPS-induced TLR4 activation in rat osteoarthritic knees. Conclusion The data suggested that the inhibition of TLR4 signal might be an important mechanism underlying a protective effect of local curcumin administration on OA.
Assuntos
Animais , Masculino , Ratos , Osteoartrite/prevenção & controle , Ligamento Cruzado Anterior/cirurgia , Curcumina/farmacologia , Osteoartrite/induzido quimicamente , Osteoartrite/metabolismo , Ensaio de Imunoadsorção Enzimática , Lipopolissacarídeos , Western Blotting , Reação em Cadeia da Polimerase , Ligamento Cruzado Anterior/patologia , NF-kappa B/metabolismo , Linfotoxina-alfa/metabolismo , Modelos Animais de Doenças , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Interleucina-1beta/metabolismo , Injeções Intra-ArteriaisRESUMO
Acute lung injury (ALI) is a serious clinical syndrome with a high rate of mortality. The activation of inflammation is well-recognized as a vital factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI. Therefore, suppression of the inflammatory response could be an ideal strategy to prevent ALI. Epigallocatechin-3-gallate (EGCG), mainly from green tea, has been shown to have an anti-inflammatory effect. The aim of the study was to explore whether EGCG alleviates inflammation in sepsis-related ALI. Male BALB/C mice were treated with EGCG (10 mg/kg) intraperitoneally (ip) 1 h before LPS injection (10 mg/kg, ip). The results showed that EGCG attenuated LPS-induced ALI as it decreased the changes in blood gases and reduced the histological lesions, wet-to-dry weight ratios, and myeloperoxidase (MPO) activity. In addition, EGCG significantly decreased the expression of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the lung, serum, and bronchoalveolar lavage fluid, and alleviated the expression of TLR-4, MyD88, TRIF, and p-p65 in the lung tissue. In addition, it increased the expression of IκB-α and had no influence on the expression of p65. Collectively, these results demonstrated the protective effects of EGCG against LPS-induced ALI in mice through its anti-inflammatory effect that may be attributed to the suppression of the activation of TLR 4-dependent NF-κB signaling pathways.
Assuntos
Animais , Masculino , Coelhos , Catequina/análogos & derivados , NF-kappa B/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Lesão Pulmonar Aguda/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Catequina/administração & dosagem , Lipopolissacarídeos , Modelos Animais de Doenças , Lesão Pulmonar Aguda/induzido quimicamente , Camundongos Endogâmicos BALB CRESUMO
Eikenella corrodens is a gram-negative bacterium, and although primarily associated with periodontal infections or infective endocarditis, it has been identified in coronary atheromatous plaques. The effect of its lipopolysaccharide (LPS) on human coronary artery endothelial cells (HCAECs) is unknown. Our aim was to examine the mechanism underlying the inflammatory response in HCAECs stimulated with E. corrodens-LPS and to evaluate monocyte adhesion. Endothelial responses were determined by measuring the levels of chemokines and cytokines using flow cytometry. The surface expression of intercellular adhesion molecule 1 (ICAM-1) was determined using a cell-based ELISA, and the adhesion of THP-1 monocytes to HCAECs was also monitored. The involvement of toll-like receptors (TLRs) 2 and 4 was examined using TLR-neutralizing antibodies, and activation of extracellular signal-regulated kinase (ERK)1/2 and nuclear factor-kappa B (NF-κB) p65 were measured by western blotting and ELISA, respectively. Eikenella corrodens-LPS increased secretion of interleukin-8 (IL-8), monocyte chemotactic protein 1 (MCP-1), and granulocyte-macrophage colony-stimulating factor (GM-CSF), and expression of ICAM-1 on the surface of HCAECs, consistent with the increased adhesion of THP-1 cells. Moreover, E. corrodens-LPS interacted with TLR4, a key receptor able to maintain the levels of IL-8, MCP-1, and GM-CSF in HCAECs. Phosphorylation of ERK1/2 and activation of NF-κB p65 were also increased. The results indicate that E. corrodens-LPS activates HCAECs through TLR4, ERK, and NF-κB p65, triggering a pro-atherosclerotic endothelial response and enhancing monocyte adhesion.
Assuntos
Doença da Artéria Coronariana/induzido quimicamente , Doença da Artéria Coronariana/imunologia , Vasos Coronários/efeitos dos fármacos , Eikenella corrodens/metabolismo , Células Endoteliais/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/imunologia , Monócitos/efeitos dos fármacos , Anticorpos Neutralizantes , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Quimiocina CCL2/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-8/metabolismo , Lipopolissacarídeos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fosforilação , Células THP-1/imunologia , Receptor 2 Toll-Like , Receptor 4 Toll-Like/efeitos dos fármacosRESUMO
Glucocorticoid insensitivity is an important barrier to the treatment of several inflammatory diseases, including acute lung injury (ALI). Saquinavir (SQV) is an inhibitor of the human immunodeficiency virus protease, and the therapeutic effects of SQV in ALI accompanied with glucocorticoid insensitivity have not been previously investigated. In this study, the effects of SQV on lipopolysaccharide (LPS)-mediated injury in human pulmonary microvascular endothelial cells (HPMECs), human type I alveolar epithelial cells (AT I), and alveolar macrophages were determined. In addition, the effects of SQV on an LPS-induced ALI model with or without methylprednisolone (MPS) were studied. In LPS-stimulated HPMECs, SQV treatment resulted in a decrease of high mobility group box 1 (HMGB1), phospho-NF-κB (p-NF-κB), and toll-like receptor 4 (TLR4), and an increase of VE-cadherin. Compared to MPS alone, MPS plus SQV attenuated the decrease of glucocorticoid receptor alpha (GRα) and IκBα in LPS-stimulated HPMECs. HMGB1, TLR4, and p-NF-κB expression were also lessened in LPS-stimulated alveolar macrophages with SQV treatment. In addition, SQV reduced the injury in human AT I with a decrease of HMGB1 and p-NF-κB, and with an increase of aquaporin 5 (AQP 5). SQV ameliorated the lung injury caused by LPS in rats with reductions in vascular permeability, myeloperoxidase activity (MPO) and histopathological scores, and with lowered HMGB1, TLR4, and p-NF-κB expression, but with enhanced VE-cadherin expression. By comparison, SQV plus MPS increased GRα and IκBα in lung tissues of rats with ALI. This study demonstrated that SQV prevented experimental ALI and improved glucocorticoid insensitivity by modulating the HMGB1/TLR4 pathway.
Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Metilprednisolona/administração & dosagem , Saquinavir/administração & dosagem , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Antígenos CD/efeitos dos fármacos , Antígenos CD/metabolismo , Caderinas/efeitos dos fármacos , Caderinas/metabolismo , Modelos Animais de Doenças , Proteína HMGB1/efeitos dos fármacos , Proteína HMGB1/metabolismo , Lipopolissacarídeos , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismoRESUMO
Glucocorticoid insensitivity is an important barrier to the treatment of several inflammatory diseases, including acute lung injury (ALI). Saquinavir (SQV) is an inhibitor of the human immunodeficiency virus protease, and the therapeutic effects of SQV in ALI accompanied with glucocorticoid insensitivity have not been previously investigated. In this study, the effects of SQV on lipopolysaccharide (LPS)-mediated injury in human pulmonary microvascular endothelial cells (HPMECs), human type I alveolar epithelial cells (AT I), and alveolar macrophages were determined. In addition, the effects of SQV on an LPS-induced ALI model with or without methylprednisolone (MPS) were studied. In LPS-stimulated HPMECs, SQV treatment resulted in a decrease of high mobility group box 1 (HMGB1), phospho-NF-κB (p-NF-κB), and toll-like receptor 4 (TLR4), and an increase of VE-cadherin. Compared to MPS alone, MPS plus SQV attenuated the decrease of glucocorticoid receptor alpha (GRα) and IκBα in LPS-stimulated HPMECs. HMGB1, TLR4, and p-NF-κB expression were also lessened in LPS-stimulated alveolar macrophages with SQV treatment. In addition, SQV reduced the injury in human AT I with a decrease of HMGB1 and p-NF-κB, and with an increase of aquaporin 5 (AQP 5). SQV ameliorated the lung injury caused by LPS in rats with reductions in vascular permeability, myeloperoxidase activity (MPO) and histopathological scores, and with lowered HMGB1, TLR4, and p-NF-κB expression, but with enhanced VE-cadherin expression. By comparison, SQV plus MPS increased GRα and IκBα in lung tissues of rats with ALI. This study demonstrated that SQV prevented experimental ALI and improved glucocorticoid insensitivity by modulating the HMGB1/TLR4 pathway.