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1.
Int J Mol Sci ; 22(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34638569

RESUMO

Renal ischemia reperfusion injury (RIRI) is one of the main causes of acute kidney injury (AKI), which can lead to acute renal failure. The development of RIRI is so complicated that it involves many factors such as inflammatory response, oxidative stress and cell apoptosis. Ganoderic acids (GAs), as one of the main pharmacological components of Ganoderma lucidum, have been reported to possess anti-inflammatory, antioxidant, and other pharmacological effects. The study is aimed to investigate the protective effect of GAs on RIRI and explore related underlying mechanisms. The mechanisms involved were assessed by a mouse RIRI model and a hypoxia/reoxygenation model. Compared with sham-operated group, renal dysfunction and morphological damages were relieved markedly in GAs-pretreatment group. GAs pretreatment could reduce the production of pro-inflammatory factors such as IL-6, COX-2 and iNOS induced by RIRI through inhibiting TLR4/MyD88/NF-kB signaling pathway. Furthermore, GAs reduced cell apoptosis via the decrease of the ratios of cleaved caspase-8 and cleaved caspase-3. The experimental results suggest that GAs prevent RIRI by alleviating tissue inflammation and apoptosis and might be developed as a candidate drug for preventing RIRI-induced AKI.


Assuntos
Injúria Renal Aguda/prevenção & controle , Apoptose/efeitos dos fármacos , Inflamação/tratamento farmacológico , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Triterpenos/farmacologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Ratos , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo , Triterpenos/uso terapêutico
2.
Molecules ; 26(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34577169

RESUMO

Artemisinin (also known as Qinghaosu), an active component of the Qinghao extract, is widely used as antimalarial drug. Previous studies reveal that artemisinin and its derivatives also have effective anti-inflammatory and immunomodulatory properties, but the direct molecular target remains unknown. Recently, several reports mentioned that myeloid differentiation factor 2 (MD-2, also known as lymphocyte antigen 96) may be the endogenous target of artemisinin in the inhibition of lipopolysaccharide signaling. However, the exact interaction between artemisinin and MD-2 is still not fully understood. Here, experimental and computational methods were employed to elucidate the relationship between the artemisinin and its inhibition mechanism. Experimental results showed that artemether exhibit higher anti-inflammatory activity performance than artemisinin and artesunate. Molecular docking results showed that artemisinin, artesunate, and artemether had similar binding poses, and all complexes remained stable throughout the whole molecular dynamics simulations, whereas the binding of artemisinin and its derivatives to MD-2 decreased the TLR4(Toll-Like Receptor 4)/MD-2 stability. Moreover, artemether exhibited lower binding energy as compared to artemisinin and artesunate, which is in good agreement with the experimental results. Leu61, Leu78, and Ile117 are indeed key residues that contribute to the binding free energy. Binding free energy analysis further confirmed that hydrophobic interactions were critical to maintain the binding mode of artemisinin and its derivatives with MD-2.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Artemisininas/química , Artemisininas/farmacologia , Antígeno 96 de Linfócito/antagonistas & inibidores , Antígeno 96 de Linfócito/química , Animais , Artemeter/farmacologia , Artesunato/farmacologia , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a Ácido Graxo/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Imunomodulação/efeitos dos fármacos , Técnicas In Vitro , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/efeitos dos fármacos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Óxido Nítrico/metabolismo , Ligação Proteica , Termodinâmica , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/química , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
J Med Chem ; 64(16): 12261-12272, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34382796

RESUMO

Modern adjuvants for vaccine formulations are immunostimulating agents whose action is based on the activation of pattern recognition receptors (PRRs) by well-defined ligands to boost innate and adaptive immune responses. Monophosphoryl lipid A (MPLA), a detoxified analogue of lipid A, is a clinically approved adjuvant that stimulates toll-like receptor 4 (TLR4). The synthesis of MPLA poses manufacturing and quality assessment challenges. Bridging this gap, we report here the development and preclinical testing of chemically simplified TLR4 agonists that could sustainably be produced in high purity and on a large scale. Underpinned by computational and biological experiments, we show that synthetic monosaccharide-based molecules (FP compounds) bind to the TLR4/MD-2 dimer with submicromolar affinities stabilizing the active receptor conformation. This results in the activation of MyD88- and TRIF-dependent TLR4 signaling and the NLRP3 inflammasome. FP compounds lack in vivo toxicity and exhibit adjuvant activity by stimulating antibody responses with a potency comparable to MPLA.


Assuntos
Adjuvantes Imunológicos/farmacologia , Glucosamina/farmacologia , Glicolipídeos/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Adjuvantes Imunológicos/síntese química , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/toxicidade , Animais , Feminino , Glucosamina/síntese química , Glucosamina/metabolismo , Glucosamina/toxicidade , Glicolipídeos/síntese química , Glicolipídeos/metabolismo , Glicolipídeos/toxicidade , Humanos , Inflamassomos/metabolismo , Interleucina-1/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
4.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206009

RESUMO

Toll-like receptor (TLR) signaling plays a critical role in the induction and progression of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematous, experimental autoimmune encephalitis, type 1 diabetes mellitus and neurodegenerative diseases. Deciphering antigen recognition by antibodies provides insights and defines the mechanism of action into the progression of immune responses. Multiple strategies, including phage display and hybridoma technologies, have been used to enhance the affinity of antibodies for their respective epitopes. Here, we investigate the TLR4 antibody-binding epitope by computational-driven approach. We demonstrate that three important residues, i.e., Y328, N329, and K349 of TLR4 antibody binding epitope identified upon in silico mutagenesis, affect not only the interaction and binding affinity of antibody but also influence the structural integrity of TLR4. Furthermore, we predict a novel epitope at the TLR4-MD2 interface which can be targeted and explored for therapeutic antibodies and small molecules. This technique provides an in-depth insight into antibody-antigen interactions at the resolution and will be beneficial for the development of new monoclonal antibodies. Computational techniques, if coupled with experimental methods, will shorten the duration of rational design and development of antibody therapeutics.


Assuntos
Anticorpos Monoclonais/imunologia , Artrite Reumatoide/imunologia , Encefalite/imunologia , Epitopos/genética , Doença de Hashimoto/imunologia , Doenças Neurodegenerativas/imunologia , Receptor 4 Toll-Like/genética , Sequência de Aminoácidos/genética , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Técnicas de Visualização da Superfície Celular , Encefalite/genética , Encefalite/patologia , Mapeamento de Epitopos/métodos , Epitopos/imunologia , Doença de Hashimoto/genética , Doença de Hashimoto/patologia , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Ligação Proteica/genética , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/imunologia
5.
Molecules ; 26(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073777

RESUMO

House dust mites (HDM) are critical factors in airway inflammation. They activate respiratory epithelial cells to produce reactive oxygen species (ROS) and activate Toll-like receptor 4 (TLR4). ROS induce the expression of inflammatory cytokines in respiratory epithelial cells. Lycopene is a potent antioxidant nutrient with anti-inflammatory activity. The present study aimed to investigate whether HDM induce intracellular and mitochondrial ROS production, TLR4 activation, and pro-inflammatory cytokine expression (IL-6 and IL-8) in respiratory epithelial A549 cells. Additionally, we examined whether lycopene inhibits HDM-induced alterations in A549 cells. The treatment of A549 cells with HDM activated TLR4, induced the expression of IL-6 and IL-8, and increased intracellular and mitochondrial ROS levels. TAK242, a TLR4 inhibitor, suppressed both HDM-induced ROS production and cytokine expression. Furthermore, lycopene inhibited the HDM-induced TLR4 activation and cytokine expression, along with reducing the intracellular and mitochondrial ROS levels in HDM-treated cells. These results collectively indicated that the HDM induced TLR4 activation and increased intracellular and mitochondrial ROS levels, thus resulting in the induction of cytokine expression in respiratory epithelial cells. The antioxidant lycopene could inhibit HDM-induced cytokine expression, possibly by suppressing TLR4 activation and reducing the intracellular and mitochondrial ROS levels in respiratory epithelial cells.


Assuntos
Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Licopeno/farmacologia , Pyroglyphidae/metabolismo , Mucosa Respiratória/metabolismo , Receptor 4 Toll-Like/metabolismo , Células A549 , Animais , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores
6.
Mol Med Rep ; 24(2)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34109422

RESUMO

Mycoplasma pneumoniae (MP) is a common pathogen that can cause respiratory infections. MP pneumonia (MPP) leads to numerous complications, including lung injury and even death. The present study aimed to investigate the protective effects of Baicalin treatment on MP infection­induced lung injury and the molecular mechanism underlying these effects. Briefly, after mice were infected intranasally by MP and treated with Baicalin (80 mg/kg), serum levels of MP­immunoglobulin M (IgM) were detected by ELISA. The expression levels of C­reactive protein (CRP) in lung tissue were detected by immunohistochemistry and the bronchoalveolar lavage fluid (BALF) was examined by ELISA. Inflammatory factors and inflammatory cells in the BALF were assessed. The expression levels of microRNA (miR)­221 in lung tissue were examined by reverse transcription­quantitative PCR and pathological changes in lung tissue were detected by H&E staining. Cell apoptosis was evaluated by TUNEL assay and the protein expression levels of TLR4, MyD88 and NF­κB were detected by western blotting. Baicalin treatment significantly reduced serum levels of MP­IgM and CRP expression in lung tissue during MP infection. In addition, Baicalin decreased the levels of IL­1ß, IL­6, IL­18 and TNF­α in the BALF, and the number of inflammatory cells. Baicalin also reduced the inflammatory infiltration in lung tissue induced by MP infection, improved the pathological changes detected in lung tissue, reduced apoptosis, and downregulated the protein expression levels of TLR4, MyD88 and NF­κB. Furthermore, Baicalin treatment downregulated the expression of miR­221 and the protective effects of Baicalin were attenuated by miR­221 overexpression. In conclusion, Baicalin has a therapeutic effect on mice with MP infection­induced lung injury, which may be related to inhibition of miR­221 expression and regulation of the TLR4/NF­κB signaling pathway.


Assuntos
Anti-Infecciosos/farmacologia , Flavonoides/farmacologia , Lesão Pulmonar/tratamento farmacológico , MicroRNAs/genética , Pneumonia por Mycoplasma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Anti-Infecciosos/uso terapêutico , Apoptose/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/imunologia , Proteínas de Transporte/metabolismo , Citocinas/imunologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Feminino , Flavonoides/uso terapêutico , Imunoglobulina M/sangue , Lesão Pulmonar/etiologia , Lesão Pulmonar/patologia , Camundongos Endogâmicos BALB C , MicroRNAs/efeitos dos fármacos , Mycoplasma pneumoniae/efeitos dos fármacos , Mycoplasma pneumoniae/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Pneumonia por Mycoplasma/complicações , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
7.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068193

RESUMO

In this study, we investigate the immunomodulatory effects of a novel antimicrobial peptide, YD1, isolated from Kimchi, in both in vitro and in vivo models. We establish that YD1 exerts its anti-inflammatory effects via up-regulation of the Nrf2 pathway, resulting in the production of HO-1, which suppresses activation of the NF-κB pathway, including the subsequent proinflammatory cytokines IL-1ß, IL-6, and TNF-α. We also found that YD1 robustly suppresses nitric oxide (NO) and prostaglandin E2 (PGE2) production by down-regulating the expression of the upstream genes, iNOS and COX-2, acting as a strong antioxidant. Collectively, YD1 exhibits vigorous anti-inflammatory and antioxidant activity, presenting it as an interesting potential therapeutic agent.


Assuntos
Anti-Inflamatórios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Inflamação/prevenção & controle , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Citocinas/metabolismo , Edema/induzido quimicamente , Edema/metabolismo , Edema/patologia , Edema/prevenção & controle , Heme Oxigenase-1/genética , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Proteínas de Membrana/genética , Camundongos , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 2 Relacionado a NF-E2/genética , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
8.
Phytomedicine ; 87: 153569, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33985878

RESUMO

BACKGROUND: Toll-like receptor 2 and Toll-like receptor 4 (TLR2/4) on microglia have been found as important regulators in the inflammatory response during cerebral ischemia/reperfusion (I/R). In China, traditional Chinese medicine Salvia miltiorrhiza (danshen) and its some components are considered to be effective in rescuing cerebral I/R injury through clinical practice. HYPOTHESIS/PURPOSE: Here we examined the effect of Salvianolic acid A (SAA), a monomer compound in the water extract of Salvia miltiorrhiza, on TLR2/4 of microglia and its mediated inflammatory injury during cerebral I/R in vivo and in vitro. STUDY DESIGN: For exploring the effect of SAA on cerebral I/R and TLR2/4, classic middle cerebral artery occlusion (MCAO) model and oxygen glucose deprivation / reoxygenation (OGD/R) model of co-culture with primary hippocampal neurons and microglia in vitro were used. Signal pathway research and gene knockout have been applied to further explain its mechanism. METHODS: The evaluation indexes of I/R injury included infarct size, edema degree and pathology as well as primary hippocampal neurons and microglia culture, ELISA, western, RT-PCR, HE staining, immunofluorescence, flow cytometry, siRNA gene knockout were also employed. RESULTS: SAA significantly improved the degree of brain edema and ischemic area in I/R rats accompanied by decreases in levels of interleukin-1ß (IL-1ß) and tumor necrosis factor-alpha (TNF-α). Pathological staining revealed that SAA could reduce inflammatory cell infiltration and mcirogila activation after reperfusion. Both protein and gene expression of TLR2 and TLR4 in ischemic hemisphere were obviously inhibited by SAA treatment while changes were not found in the non-ischemic hemisphere. In order to further study its mechanism, OGD/R model was used to mimic inflammatory damage of ischemic tissue by co-culturing primary rat hippocampal neurons and microglial cells. It was found that SAA also inhibited the protein and gene expression of TLR2 and TLR4 after OGD/R injury in microglia. After TLR2/4 knockout, the inhibitory effect of SAA on IL-1ß and TNF-α levels in cell supernatant and neuron apoptosis were significantly weakened in each dose group. Moreover, expression levels of myeloid differentiation factor 88 (MyD88), NFκB, IL-1ß and IL-6 in TLR2/4 mediated inflammatory pathway were reduced with SAA treatment. CONCLUSION: SAA could significantly reduce the inflammatory response and injury in cerebral ischemia-reperfusion in vivo and in vitro, and its mechanism may be through the inhibition of TLR2/4 and its related signal pathway.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ácidos Cafeicos/farmacologia , Lactatos/farmacologia , Microglia/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Isquemia Encefálica/patologia , Ácidos Cafeicos/uso terapêutico , Infarto da Artéria Cerebral Média , Inflamação/metabolismo , Lactatos/uso terapêutico , Masculino , Microglia/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética
9.
Theranostics ; 11(13): 6225-6239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995655

RESUMO

Colitis-associated colorectal cancer (CAC) develops from chronic intestinal inflammation. Dihydroartemisinin (DHA) is an antimalarial drug exhibiting anti-inflammatory and anti-tumor effects. Nonetheless, the therapeutic effects of DHA on CAC remain unestablished. Methods: Mice were challenged with azoxymethane (AOM) and dextran sulfate sodium (DSS) to establish CAC models. DHA was administered via oral gavage in different stages of CAC models. Colon and tumor tissues were obtained from the AOM/DSS models to investigate inflammatory responses and tumor development. Inflammatory cytokines in the murine models were detected through qRT-PCR and ELISA. Toll-like receptor 4 (TLR4) signaling-related proteins were detected by western blot. Macrophage infiltration was measured using immunostaining analysis, and apoptosis in the colon cancer cells was detected by flow cytometry and western blot. Results: DHA inhibited inflammatory responses in the early stage of the AOM/DSS model and subsequent tumor formation. In the early stage, DHA reversed macrophage infiltration in colon mucosa and decreased the expression of pro-inflammatory cytokines. DHA inhibited the activation of macrophage by suppressing the TLR4 signal pathway. In the late stage of CAC, DHA inhibited tumor growth by enhancing cell cycle arrest and apoptosis in tumor cells. Administration of DHA during the whole period of the AOM/DSS model generated an addictive effect based on the inhibition of inflammation and tumor growth, thereby improving the therapeutic effect of DHA on CAC. Conclusion: Our study indicated that DHA could be a potent agent in managing the initiation and development of CAC without obvious side effects, warranting further clinical translation of DHA for CAC treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Artemisininas/uso terapêutico , Neoplasias Associadas a Colite/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Artemisininas/farmacologia , Linhagem Celular Tumoral , Colite/induzido quimicamente , Colite/patologia , Citocinas/análise , Ensaios de Seleção de Medicamentos Antitumorais , Macrófagos Peritoneais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/análise , Receptor 4 Toll-Like/antagonistas & inibidores
10.
Phys Chem Chem Phys ; 23(21): 12260-12269, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34013938

RESUMO

Nalmefene is an opiate derivative having a similar structure to naltrexone. Recent evidence suggests that nalmefene, acting as the innate immune protein toll-like receptor 4 (TLR4) antagonist, effectively reduces the injury of lung ischemia-reperfusion and prevents neuroinflammation. However, the molecular recognition mechanism, especially the enantioselectivity, of nalmefene by the innate immune receptor is not well understood. Herein in vitro assays and in silico simulations were performed to dissect the innate immune recognition of nalmefene at the atomic, molecular, and cellular levels. Biophysical binding experiments and molecular dynamic simulations provide direct evidence that (-)-nalmefene and (+)-nalmefene bind to the hydrophobic cavity of myeloid differentiation protein 2 (MD-2) and behave similarly, which is primarily driven by hydrophobic interactions. The inhibition activity and the calculated binding free energies show that no enantioselectivity was observed during the interaction of nalmefene with MD-2 as well as the inhibition of TLR4 signaling. Interestingly, nalmefene showed ∼6 times better TLR4 antagonisic activity than naltrexone, indicating that the bioisosteric replacement with the methylene group is critical for the molecular recognition of nalmefene by MD-2. In all, this study provides molecular insight into the innate immune recognition of nalmefene, which demonstrates that nalmefene is non-enantioselectively sensed by MD-2.


Assuntos
Antígeno 96 de Linfócito/antagonistas & inibidores , Naltrexona/análogos & derivados , Antagonistas de Entorpecentes/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Células Cultivadas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Antígeno 96 de Linfócito/genética , Antígeno 96 de Linfócito/isolamento & purificação , Camundongos , Conformação Molecular , Simulação de Dinâmica Molecular , Naltrexona/química , Naltrexona/farmacologia , Antagonistas de Entorpecentes/química , Transdução de Sinais/efeitos dos fármacos , Estereoisomerismo , Termodinâmica
11.
Biosci Biotechnol Biochem ; 85(7): 1665-1674, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34014269

RESUMO

This study aims to explore the effect of Tectorigenin in chronic cerebral ischemia (CCI)-induced cognitive impairment mice model. Cognitive impairment, hippocampal tissue histopathology, and myelin density in CCI mice were detected. HT22 cells were used to induce oxygen-glucose deprivation/reperfusion (OGD/R) injury. Cell viability and apoptosis of transfected HT22 cells and toll-like receptor-4 (TLR4)/nuclear factor-kappaB (NF-κB) pathway-related factor levels in hippocampal tissue and OGD/R models were detected. CCI caused cognitive impairment, hippocampal damage, and decreased myelin density in mice while promoting interleukin-1ß, tumor necrosis factor-alpha, TLR4, myeloid differentiation primary response gene 88, p-p65, NLRP3, and ASC levels. Tectorigenin reversed the effects of CCI in mice and reversed the promoting effects of OGD/R on apoptosis and TLR4/NF-κB pathway-related factors levels, while overexpressed TLR4 reversed the effects of Tectorigenin in OGD/R-induced HT-22 cells. Tectorigenin alleviated cognitive impairment in CCI mice by inhibiting the TLR4/NF-κB signaling pathway.


Assuntos
Isquemia Encefálica/complicações , Transtornos Cognitivos/prevenção & controle , Isoflavonas/farmacologia , NF-kappa B/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Doença Crônica , Transtornos Cognitivos/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo
12.
Front Immunol ; 12: 669747, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025672

RESUMO

Patients suffering from ulcerative colitis are at increased risk of developing colorectal cancer. Although the exact underlying mechanisms of inflammation-associated carcinogenesis remain unknown, the intestinal microbiota as well as pathogenic bacteria are discussed as contributors to inflammation and colitis-associated colon cancer (CAC). In the present study, we analyzed the impact of TLR4, the receptor for Gram-negative bacteria derived lipopolysaccharides, on intestinal inflammation and tumorigenesis in a murine model of CAC. During the inflammatory phases of CAC development, we observed a strong upregulation of Tlr4 expression in colonic tissues. Blocking of TLR4 signaling by a small-molecule-specific inhibitor during the inflammatory phases of CAC strongly diminished the development and progression of colonic tumors, which was accompanied by decreased numbers of infiltrating macrophages and reduced colonic pro-inflammatory cytokine levels compared to CAC control mice. Interestingly, inhibiting bacterial signaling by antibiotic treatment during the inflammatory phases of CAC also protected mice from severe intestinal inflammation and almost completely prevented tumor growth. Nevertheless, application of antibiotics involved rapid and severe body weight loss and might have unwanted side effects. Our results indicate that bacterial activation of TLR4 on innate immune cells in the colon triggers inflammation and promotes tumor growth. Thus, the inhibition of the TLR4 signaling during intestinal inflammation might be a novel approach to impede CAC development.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Associadas a Colite/prevenção & controle , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Linhagem Celular Tumoral , Colite/metabolismo , Colite/microbiologia , Colite/patologia , Neoplasias Associadas a Colite/metabolismo , Neoplasias Associadas a Colite/microbiologia , Neoplasias Associadas a Colite/patologia , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Citocinas/metabolismo , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos Endogâmicos BALB C , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Carga Tumoral/efeitos dos fármacos , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo
13.
Sci Rep ; 11(1): 10531, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006936

RESUMO

Ceramic orthopaedic implants are increasingly popular due to the need for robust total joint replacement implants that have a high success rate long-term and do not induce biological responses in patients. This study was designed to investigate the biological effects of ceramic nanopowders containing aluminium oxide or zirconium oxide to activate the human macrophage THP-1 cell line. In vitro investigation of pro-inflammatory gene expression and chemokine secretion was performed studied using RT-qPCR and ELISA, respectively. TLR4 inhibition, using a small-molecule inhibitor, was used to determine whether ceramic-mediated inflammation occurs in a similar manner to that of metals such as cobalt. THP-1 macrophages were primed with ceramics or LPS and then treated with ATP or ceramics, respectively, to determine whether these nanopowders are involved in the priming or activation of the NLRP3 inflammasome through IL-1ß secretion. Cells treated with ceramics significantly increased pro-inflammatory gene expression and protein secretion which was attenuated through TLR4 blockade. Addition of ATP to cells following ceramic treatment significantly increased IL-1ß secretion. Therefore, we identify the ability of ceramic metal oxides to cause a pro-inflammatory phenotype in THP-1 macrophages and propose the mechanism by which this occurs is primarily via the TLR4 pathway which contributes to inflammasome signalling.


Assuntos
Óxido de Alumínio/farmacologia , Cerâmica , Inflamação/induzido quimicamente , Nanopartículas/química , Pós/farmacologia , Zircônio/farmacologia , Artroplastia de Quadril , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Fagocitose , Células THP-1 , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
14.
Carbohydr Polym ; 263: 117998, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33858583

RESUMO

Herein, dual-bioresponsive of Rhein (RH) in promoting colonic mucous damage repair and controlling inflammatory reactions were combined by the dual-targeting (intestinal epithelial cells and macrophages) oral nano delivery strategy for effective therapy of ulcerative colitis (UC). Briefly, two carbohydrates, calcium pectinate (CP) and hyaluronic acid (HA) were used to modify lactoferrin (LF) nanoparticles (NPs) to encapsulate RH (CP/HA/RH-NPs). CP layer make CP/HA/RH-NPs more stable and protect against the destructive effects of the gastrointestinal environment and then release HA/RH-NPs to colon lesion site. Cellular uptake evaluation confirmed that NPs could specifically target and enhance the uptake rate via LF and HA ligands. in vivo experiments revealed that CP/HA/RH-NPs significantly alleviated inflammation by inhibiting the TLR4/MyD88/NF-κB signaling pathway and accelerated colonic healing. Importantly, with the help of CP, this study was the first to attempt for LF as a targeting nanomaterial in UC treatment and offers a promising food-based nanodrug in anti-UC.


Assuntos
Antraquinonas/farmacologia , Colite Ulcerativa/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Ácido Hialurônico/química , Lactoferrina/química , Nanopartículas/química , Pectinas/química , Animais , Antraquinonas/química , Transporte Biológico , Linhagem Celular , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Citocinas/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Inibidores Enzimáticos/química , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/antagonistas & inibidores , Nanopartículas/uso terapêutico , Receptores de Superfície Celular/metabolismo , Proteínas de Junções Íntimas/metabolismo , Distribuição Tecidual , Receptor 4 Toll-Like/antagonistas & inibidores
15.
J Neurosci ; 41(19): 4349-4365, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846230

RESUMO

Complex regional pain syndrome (CRPS) is a chronic pain disorder with a clear acute-to-chronic transition. Preclinical studies demonstrate that toll-like receptor 4 (TLR4), expressed by myeloid-lineage cells, astrocytes, and neurons, mediates a sex-dependent transition to chronic pain; however, evidence is lacking on which exact TLR4-expressing cells are responsible. We used complementary pharmacologic and transgenic approaches in mice to more specifically manipulate myeloid-lineage TLR4 and outline its contribution to the transition from acute-to-chronic CRPS based on three key variables: location (peripheral vs central), timing (prevention vs treatment), and sex (male vs female). We demonstrate that systemic TLR4 antagonism is more effective at improving chronic allodynia trajectory when administered at the time of injury (early) in the tibial fracture model of CRPS in both sexes. In order to clarify the contribution of myeloid-lineage cells peripherally (macrophages) or centrally (microglia), we rigorously characterize a novel spatiotemporal transgenic mouse line, Cx3CR1-CreERT2-eYFP;TLR4fl/fl (TLR4 cKO) to specifically knock out TLR4 only in microglia and no other myeloid-lineage cells. Using this transgenic mouse, we find that early TLR4 cKO results in profound improvement in chronic, but not acute, allodynia in males, with a significant but less robust effect in females. In contrast, late TLR4 cKO results in partial improvement in allodynia in both sexes, suggesting that downstream cellular or molecular TLR4-independent events may have already been triggered. Overall, we find that the contribution of TLR4 is time- and microglia-dependent in both sexes; however, females also rely on peripheral myeloid-lineage (or other TLR4 expressing) cells to trigger chronic pain.SIGNIFICANCE STATEMENT The contribution of myeloid cell TLR4 to sex-specific pain progression remains controversial. We used complementary pharmacologic and transgenic approaches to specifically manipulate TLR4 based on three key variables: location (peripheral vs central), timing (prevention vs treatment), and sex (male vs female). We discovered that microglial TLR4 contributes to early pain progression in males, and to a lesser extent in females. We further found that maintenance of chronic pain likely occurs through myeloid TLR4-independent mechanisms in both sexes. Together, we define a more nuanced contribution of this receptor to the acute-to-chronic pain transition in a mouse model of complex regional pain syndrome.


Assuntos
Dor Crônica/genética , Células Mieloides/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Dor Crônica/tratamento farmacológico , Dor Crônica/metabolismo , Síndromes da Dor Regional Complexa/tratamento farmacológico , Síndromes da Dor Regional Complexa/genética , Feminino , Humanos , Hiperalgesia/tratamento farmacológico , Hiperalgesia/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microglia/metabolismo , Medição da Dor/efeitos dos fármacos , Caracteres Sexuais , Sulfonamidas/uso terapêutico , Fraturas da Tíbia/complicações , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética
16.
J Med Microbiol ; 70(4)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33830910

RESUMO

Introduction. Clostridioides difficile infection (CDI) causes toxin-mediated enteropathy, such as antibiotic-associated diarrhoea and pseudomembranous colitis. Rho-glucosylating toxin A (TcdA) and toxin B (TcdB) have been clearly implicated in pathogenesis, whereas the virulence of binary toxin (CDT) is still debated.Hypothesis statement. We hypothesized that CDT is involved in the host immune response and plays a pivotal role in establishing virulence by modulating pro-inflammatory cytokine production; this is achieved through the integral Toll-like receptor (TLR) signalling pathways.Aim. The aim of the present study was to determine whether and how CDT impacts macrophages compared to TcdA or TcdB by examining the induction of CXC chemokine ligand 2 (CXCL2) and tumour necrosis factor-α (TNF-α), both of which are crucial in mediating local and systematic inflammatory responses.Methodology. RAW264.7 cells or transfected human embryonic kidney (HEK) 293 T cells were incubated with TcdA, TcdB, or CDT. In some experiments, a neutralizing antibody against TLR2 or TLR4, or myeloid differentiation 88 inhibitory peptide were added. The amount of CXCL2 and TNF-α secreted was then measured.Results. In RAW264.7 macrophages, CXCL2 and TNF-α were produced via the Toll-like receptor 2 (TLR2) or Toll-like receptor 4 (TLR4) pathway in a TcdA, TcdB, or CDT dose-dependent manner. Interleukin-8 secretion was induced in TLR4/MD2/CD14-transfected, but not in TLR2-transfected, HEK 293 T cells following TcdB or CDT exposure.Conclusion. Our results showed that C. difficile toxins, including CDT, enhanced macrophage-mediated CXCL2 and TNF-α production via TLR2 and TLR4, indicating that CDT affects host immune responses.


Assuntos
Toxinas Bacterianas/farmacologia , Quimiocina CXCL2/metabolismo , Clostridioides difficile/patogenicidade , Macrófagos/efeitos dos fármacos , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células HEK293 , Humanos , Macrófagos/metabolismo , Camundongos , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Fator 88 de Diferenciação Mieloide/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Virulência
17.
Mol Med Rep ; 23(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33655339

RESUMO

Toll­like receptor (TLR) 2/4 serves an important regulatory role in nerve tissue injury. However, the downstream and potential mechanisms remain to be elucidated. The present study was designed to investigate the roles of the TLR2/4­major myeloid differentiation response gene 88 (MyD88)­NF­κB signaling pathway in the development of intracranial aneurysm. The expression of TLR2, TLR4 and MyD88 in the blood of normal controls and patients with intracranial aneurysm were detected by quantitative PCR and ELISA. Human brain vascular smooth muscle cells were treated by Angiotensin II (Ang II) to evaluate the involvement of TLR2/4­MyD88­NF­κB signaling pathway in the process. The in vitro experiment was divided into four groups: The control group, an Ang â…¡ group, an Ang â…¡ + small interfering (si)RNA control group and an Ang â…¡ + TLR2­group. Cell viability, migration, apoptosis and expression of TLR2, TLR4, MyD88, NF­κB and phosphorylated (p­)p65 expression were detected. The results demonstrated that the expression of TLR2, TLR4, MyD88 and NF­κB at mRNA and protein levels in patients with intracranial aneurysm was significantly higher compared with corresponding protein in normal controls (P<0.05). In vitro experiments demonstrated that Ang â…¡ treatment increased the cell proliferation and migration rate but reduced the apoptotic rate compared with the control (P<0.05). The expression of TLR2, TLR4, MyD88, NF­κB and p­p65 was significantly increased in the Ang II group (vs. control; P<0.05). By contrast, TLR2­short interfering RNA reduced the cell proliferation and migration rate, and reduced the expression of TLR2, TLR4, MyD88, NF­κB and p­p65 (vs. Ang â…¡ + short interfering RNA control; P<0.05). In conclusion, the data of the present study indicated that the TLR2/4­MyD88­NF­κB signaling pathway is involved in the pathogenesis of intracranial aneurysm.


Assuntos
Aneurisma Intracraniano/genética , Fator 88 de Diferenciação Mieloide/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Angiotensina II/farmacologia , Feminino , Regulação da Expressão Gênica/genética , Humanos , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/terapia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , NF-kappa B/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética
18.
Mol Nutr Food Res ; 65(10): e2000943, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33650755

RESUMO

SCOPE: Coconut oil (CO) diets remain controversial due to the possible association with metabolic disorder and obesity. This study investigates the metabolic effects of a low amount of CO supplementation. METHODS AND RESULTS: Swiss male mice are assigned to be supplemented orally during 8 weeks with 300 µL of water for the control group (CV), 100 or 300 µL of CO (CO100 and CO300) and 100 or 300 µL of soybean oil (SO; SO100 and SO300). CO led to anxious behavior, increase in body weight gain, and adiposity. In the hypothalamus, CO and SO increase cytokines expression and pJNK, pNFKB, and TLR4 levels. Nevertheless, the adipose tissue presented increases macrophage infiltration, TNF-α and IL-6 after CO and SO consumption. IL-1B and CCL2 expression, pJNK and pNFKB levels increase only in CO300. In the hepatic tissue, CO increases TNF-α and chemokines expression. Neuronal cell line (mHypoA-2/29) exposed to serum from CO and SO mice shows increased NFKB migration to the nucleus, TNF-α, and NFKBia expression, but are prevented by inhibitor of TLR4 (TAK-242). CONCLUSIONS: These results show that a low-dose CO changes the behavioral pattern, induces inflammatory pathway activation, TLR4 expression in healthy mice, and stimulates the pro-inflammatory response through a TLR4-mediated mechanism.


Assuntos
Comportamento Animal/efeitos dos fármacos , Óleo de Coco/administração & dosagem , Óleo de Coco/efeitos adversos , Doenças Hipotalâmicas/induzido quimicamente , Inflamação/induzido quimicamente , Doenças Metabólicas/induzido quimicamente , Adiposidade/efeitos dos fármacos , Animais , Glicemia/análise , Suplementos Nutricionais , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/fisiologia , Ganho de Peso/efeitos dos fármacos
19.
Indian J Gastroenterol ; 40(1): 5-21, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33666891

RESUMO

Gastrointestinal inflammation is a hallmark of highly prevalent disorders, including cancer treatment-induced mucositis and ulcerative colitis. These disorders cause debilitating symptoms, have a significant impact on quality of life, and are poorly managed. The activation of toll-like receptor 4 (TLR4) has been proposed to have a major influence on the inflammatory signalling pathways of the intestinal tract. Inhibition of TLR4 has been postulated as an effective way to treat intestinal inflammation. However, there are a limited number of studies looking into the potential of TLR4 antagonism as a therapeutic approach for intestinal inflammation. This review surveyed available literature and reported on the in vitro, ex vivo and in vivo effects of TLR4 antagonism on different models of intestinal inflammation. Of the studies reviewed, evidence suggests that there is indeed potential for TLR4 antagonists to treat inflammation, although only a limited number of studies have investigated treating intestinal inflammation with TLR4 antagonists directly. These results warrant further research into the effect of TLR4 antagonists in the intestinal tract.


Assuntos
Anti-Inflamatórios/farmacologia , Fármacos Gastrointestinais/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Intestinos/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Humanos , Inflamação , Transdução de Sinais/efeitos dos fármacos
20.
J Neuroinflammation ; 18(1): 77, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33752705

RESUMO

BACKGROUND: While the etiology remains elusive, macrophages and T cells in peripheral nerves are considered as effector cells mediating autoimmune peripheral neuropathy (APN), such as Guillain-Barre syndrome. By recognizing both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) signals, TLRs play a central role in the initiation of both innate and adaptive immune responses. In this study, we aimed to understand the involvement of TLR4 in the pathogenesis of APN and explore the potential of TLR4 as a drug target for therapeutic use. METHODS: APN was induced by a partial ligation on one of the sciatic nerves in B7.2 (L31) transgenic mice which possess a predisposed inflammatory background. APN pathology and neurological function were evaluated on the other non-injured sciatic nerve. RESULTS: TLR4 and its endogenous ligand HMGB1 were highly expressed in L31 mice, in circulating immune cells and in peripheral nerves. Enhanced TLR4 signaling was blocked with TAK 242, a selective TLR4 inhibitor, before and after disease onset. Intraperitoneal administration of TAK 242 not only inhibited monocyte, macrophage and CD8+ T cell activation, but also reduced the release of pro-inflammatory cytokines. TAK 242 protected mice from severe myelin and axonal loss, resulting in a remarkable improvement in mouse motor and sensory functions. TAK 242 was effective in alleviating the disease in both preventive and reversal paradigms. CONCLUSION: The study identified the critical contribution of TLR4-mediated macrophage activation in disease course and provided strong evidence to support TLR4 as a useful drug target for treating inflammatory autoimmune neuropathy.


Assuntos
Doenças Autoimunes/fisiopatologia , Transtornos dos Movimentos/fisiopatologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Transtornos das Sensações/fisiopatologia , Receptor 4 Toll-Like/genética , Animais , Doenças Autoimunes/prevenção & controle , Doenças Autoimunes/psicologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Feminino , Proteína HMGB1/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/efeitos dos fármacos , Transtornos dos Movimentos/prevenção & controle , Transtornos dos Movimentos/psicologia , Doenças do Sistema Nervoso Periférico/psicologia , Nervo Isquiático/lesões , Transtornos das Sensações/prevenção & controle , Transtornos das Sensações/psicologia , Transdução de Sinais , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores
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