Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.066
Filtrar
1.
Nat Immunol ; 20(9): 1196-1207, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31406379

RESUMO

The response to systemic infection and injury requires the rapid adaptation of hematopoietic stem cells (HSCs), which proliferate and divert their differentiation toward the myeloid lineage. Significant interest has emerged in understanding the signals that trigger the emergency hematopoietic program. However, the mechanisms that halt this response of HSCs, which is critical to restore homeostasis, remain unknown. Here we reveal that the E3 ubiquitin ligase Speckle-type BTB-POZ protein (SPOP) restrains the inflammatory activation of HSCs. In the absence of Spop, systemic inflammation proceeded in an unresolved manner, and the sustained response in the HSCs resulted in a lethal phenotype reminiscent of hyper-inflammatory syndrome or sepsis. Our proteomic studies decipher that SPOP restricted inflammation by ubiquitinating the innate signal transducer myeloid differentiation primary response protein 88 (MYD88). These findings unearth an HSC-intrinsic post-translational mechanism that is essential for reestablishing homeostasis after emergency hematopoiesis.


Assuntos
Inflamação/imunologia , Leucocitose/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Neutrófilos/imunologia , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Animais , Linhagem Celular , Feminino , Células HEK293 , Hematopoese/imunologia , Humanos , Masculino , Camundongos , Neutrófilos/citologia , Ubiquitina-Proteína Ligases/metabolismo
2.
J Biol Regul Homeost Agents ; 33(4): 1051-1062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392878

RESUMO

The development of electronic technology has attracted attention on the biological effects of electromagnetic fields (EMFs) and electromagnetic pulse (EMP). It remains controversial whether EMP irradiation is neurotoxic or beneficial for recovery from injuryies such as cerebral ischemia. Microglia is innate immune cells in the brain, exhibiting either neurotoxicity or neuroprotection effect during various central nervous system diseases, depending on their activation into a classical (M1) or alternative (M2) phenotype, respectively. The Toll-like receptor-4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa B (NFκB) pathway is important for microglia activation. In this study, we investigated the effect of EMP on neuronal apoptosis and microglia polarization in vivo and in vitro, using an EMP of 400 kV/m and 1 hertz for 200 pulses. Short EMP irradiation (≤24 h) resulted in microglial conversion from the resting to the M1-type state, activation of the TLR4/MyD88/NFκB pathway, higher levels of inflammatory cytokines including interleukin (IL)-6, IL-1ß and tumor necrosis factor-α, as well as neuronal apoptosis induction. In contrast, long EMP irradiation (3 days) resulted in microglial activation into the M2-type, decreased apoptosis and inflammatory mediator production, and increased levels of the neuroprotective effectors IL-10, transforming growth factor beta, and brain-derived neurotrophic factor. EMP induces both neuronal damage and neuronal recovery by influencing the switch of M1/M2 polarization and the TLR4/MyD88/NFκB pathway.


Assuntos
Lesões Encefálicas/patologia , Polaridade Celular , Campos Eletromagnéticos/efeitos adversos , Microglia/citologia , Citocinas/metabolismo , Humanos , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo
3.
Chin J Nat Med ; 17(6): 461-468, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31262458

RESUMO

In the present study, we investigated anti-inflammatory effect of Cardamine komarovii flower (CKF) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). We determined the effect of CKF methanolic extracts on LPS-induced pro-inflammatory mediators NO and prostaglandin E2 (PGE2), production of pro-inflammatory cytokines (IL-1ß, TNF-α, and IL-6), and related protein expression levels of MyD88/TRIF signaling pathways in peritoneal macrophages (PMs). Nuclear translocation of NF-κB-p65 was analyzed by immunofluorescence. For the in vivo experiments, an ALI model was established to detect the number of inflammatory cells and inflammatory factors (IL-1ß, TNF-α, and IL-6) in bronchoalveolar lavage fluid (BALF) of mice. The pathological damage in lung tissues was evaluated through H&E staining. Our results showed that CKF can decrease the production of inflammatory mediators, such as NO and PGE2, by inhibiting their synthesis-related enzymes iNOS and COX-2 in LPS-induced PMs. In addition, CKF can downregulate the mRNA levels of IL-1ß, TNF-α, and IL-6 to inhibit the production of inflammatory factors. Mechanism studies indicated that CKF possesses a fine anti-inflammatory effect by regulating MyD88/TRIF dependent signaling pathways. Immunocytochemistry staining showed that the CKF extract attenuates the LPS-induced translocation of NF-kB p65 subunit in the nucleus from the cytoplasm. In vivo experiments revealed that the number of inflammatory cells and IL-1ß in BALF of mice decrease after CKF treatment. Histopathological observation of lung tissues showed that CKF can remarkably improve alveolar clearance and infiltration of interstitial and alveolar cells after LPS stimulation. In conclusion, our results suggest that CKF inhibits LPS-induced inflammatory response by inhibiting the MyD88/TRIF signaling pathways, thereby protecting mice from LPS-induced ALI.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Cardamine/química , Fator 88 de Diferenciação Mieloide/metabolismo , Extratos Vegetais/administração & dosagem , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Feminino , Flores/química , Humanos , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
4.
J Biol Regul Homeost Agents ; 33(4): 1105-1111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31332987

RESUMO

The adapter protein myeloid differentiation primary response gene 88 (MyD88) links the intracellular domains of interleukin receptors 1 and 18, and most Toll-like receptors (TLRs) to interleukin 1 receptor associated kinase (IRAK) signaling and subsequent NF-κB-mediated transcription. Previous work showed that mice with global deficiency of MyD88 (MyD88-/-) have osteopenic cancellous bone along with a reduction in osteoblastic but also osteoclastic surfaces. To further elucidate the role of MyD88 in bone, we utilized mice with osteoclast-restricted MyD88 expression in bone (MyD88OC). Bones of MyD88OC and wild type (wt) mice were examined by microCT analysis. Mechanical properties of bones were tested by three-point bending, and gene expression measured using quantitative real-time polymerase chain reaction. In MyD88OC mice, no osteopenic traits were observed, however, a drastic reduction in geometric parameters was detected. In trabecular bone a loss of connectivity density (-44%, p less than 0.0001) was measured and in cortical bone Imax (-31%, p less than 0.0001), Imin (-20%, p less than 0.001), J (-26%, p less than 0.0001) were reduced. Mechanical testing showed increased load to failure (77%, p less than 0.01) and decreased deflection at failure (-68%, p less than 0.01) of the femur. On the molecular level, relative gene expression analysis showed a (-29%, p less than 0.01) reduction in receptor activator of nuclear factor κ B ligand (RANKL) and no difference in osteoprotegerin (OPG) or RANK. Further, the bone resorption markers cathepsin K (CTSK) and tartrate-resistant acid phosphatase 5 (TRAP) were unchanged. In contrast, the bone formation markers collagen type 1 (COL1A1) and osteocalcin (OC) were decreased by -72% (p less than 0.0001) and -82% (p less than 0.0001), respectively. Together, our data suggests that the function of MyD88 in osteoclasts is sufficient to maintain bone mass, while it fails to preserve bone geometry, likely through dysfunctions in osteoblasts.


Assuntos
Reabsorção Óssea , Osso e Ossos/patologia , Fator 88 de Diferenciação Mieloide/metabolismo , Osteoclastos/citologia , Animais , Catepsina K/metabolismo , Diferenciação Celular , Colágeno Tipo I/metabolismo , Camundongos , Osteoblastos , Osteocalcina/metabolismo , Osteoclastos/metabolismo , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Fosfatase Ácida Resistente a Tartarato/metabolismo
5.
Microb Pathog ; 135: 103567, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31163250

RESUMO

Clostridium perfringens (C. perfringens), a Gram-positive bacterium, is one of the main causing piglet diarrhea, which leads serious economic loss in the world swine industries. Generally, the innate immune response plays a critical role in host defense against pathogen invasion. TLR4, a member of the TLR (Toll-like receptor) family, has been considered to implicate in the host immune responses and induce secretion of inflammatory cytokines during bacterial infection. However, little is clear about the effects of TLR4 and key signaling genes in the process of piglet inflammatory and immune responses after C. perfringens infection. This study aims to explore the effect of C. perfringens type C infection on the key mRNAs of TLR4/MyD88/NF-κB signaling pathways during the process of piglet diarrhea. In this study, the expressions of TLR4 and other key mRNAs in the TLR4/MyD88/NF-κB signaling pathways were quantified in piglet ileum and jejunum tissues among IR (intestinal resistance), IS (intestinal susceptibility) and IC (intestinal control) groups by qPCR and Western blot methods, the concentrations of pro-inflammatory cytokines in intestinal tissues and serum immunoglobulins were also tested by ELISA kits. Results showed that compared to IC group, expressions of ileum TLR4 and TNF-α was significantly increased in the IS and IR groups, specially TBK1 gene; the expressions of ileum TLR2, TRAF6, MyD88 and IL-8 mRNAs was significantly up-regulated in the IS group, the expressions of TLR9, NF-κB, IL-6, IFN-γ and MAPK1 genes were not significant differences among the IR, IS and IC groups. Meanwhile, the protein levels of TLR4, HMGB1 and NF-κB were higher in the IS and IR groups. The levels of jejunum IFN-γ and IL-6, ileum IL-6 and IL-12 were risen in the IR group. Serum immunoglobulin IgA and IgG in the IR and IS groups reached a peak on the 72 h and 48 h post infection, respectively. These findings suggest that C. perfringens type C infection induces host immune responses involving in the TLR4/MyD88/NF-κB signaling pathways in ileum than in jejunum, which may provide valuable information for innate immune mechanisms involved in regulation of piglet diarrhea caused by C. perfringens type C infection.


Assuntos
Infecções por Clostridium/imunologia , Clostridium perfringens/patogenicidade , Intestino Delgado/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Animais , Infecções por Clostridium/microbiologia , Citocinas/genética , Citocinas/metabolismo , Diarreia/imunologia , Diarreia/microbiologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Imunidade Inata , Imunoglobulinas/sangue , Intestino Delgado/microbiologia , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , Suínos , Receptor 4 Toll-Like/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Molecules ; 24(11)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181689

RESUMO

BACKGROUND: Psoriasis is a chronic, immune-mediated inflammatory skin disease, and the inflammatory response plays an important role in its development and progression. Datura metel L. is a traditional Chinese medicine that exhibited a significant therapeutic effect on psoriasis in our previous study due to its remarkable anti-inflammatory effect. Meanwhile, the mechanism underlying its effects on psoriasis is still unclear. METHODS: An imiquimod-induced psoriasis-like dermatitis mouse model was constructed to evaluate the protective effect of the effective part of Datura metel L. (EPD), which was verified by evaluations of the Psoriasis Area and Severity Index (PASI) score. Hematoxylin and eosin (H&E) staining, immunohistochemical examination, enzyme-linked immunosorbent assay (ELISA), and Western blot were used to measure the inflammatory cytokines and the protein expression associated with the Toll-like receptor 7- myeloid differentiation primary response gene 88-nuclear Factor-κB-nucleotide-binding oligomerization domain (Nod)-like receptor family pyrin domain-containing 3 (TLR7/8-MyD88-NF-κB-NLRP3) inflammasome pathway. RESULTS: EPD significantly decreased the PASI, reduced epidermal thickness, and decreased the proliferation and differentiation of epidermal cells in psoriasis-like dermatitis C57BL/6 mice induced by imiquimod (IMQ). Furthermore, EPD reduced the infiltration of CD3+ cells to psoriatic lesions, as well as ameliorated the elevations of intercellular adhesion molecule 1 (ICAM-1) and inhibited the production of imiquimod-induced inflammatory cytokines, including IL-1ß, IL-2, IL-6, IL-10, IL-12, IL-17, IL-22, IL-23, tumor necrosis factor-α (TNF-α), monocyte chemotactic protein 1 (MCP-1), and interferon-γ (IFN-γ). Besides, EPD decreased the imiquimod-induced expression levels of TLR7, TLR8, TRAF6, MyD88, p-IKKα, p-IKBα, p-NF-κB, NLRP3, apoptosis-associated speck-like protein contained a caspase recruitment domain (ASC), cysteinyl aspartate specific proteinase 1 (caspase-1), and IL-1ß. CONCLUSION: This study demonstrated that EPD exhibited a protective effect on an imiquimod-induced psoriasis mice model by inhibiting the inflammatory response, which might be ascribed to the inhibition of the TLR7/8-MyD88-NF-κb-NLRP3 inflammasome pathway.


Assuntos
Citocinas/metabolismo , Datura metel/química , Medicamentos de Ervas Chinesas/administração & dosagem , Imiquimode/efeitos adversos , Psoríase/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Regulação para Baixo , Medicamentos de Ervas Chinesas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Psoríase/induzido quimicamente , Psoríase/imunologia , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/metabolismo
7.
Artigo em Chinês | MEDLINE | ID: mdl-31177708

RESUMO

Objective: To investigate the effects of silica dust on the expression of Myeloid differentiation factor 88 (MyD88) mRNA and tumor necrosis factor receptor-associated factor (TRAF6) mRNA of lung macrophages in rats. Methods: Selecting 40 SPF-class Wistar rats with average weight (200±20) g randomly divided into control group and 30 d, 60 d, 120 d experimental groups with 10 rats in each group according to body weight. The experimental groups rats were injected with 1 ml of SiO(2) (100 mg/ml) suspension through the trachea into lung only once, then they were respectively killed after 30, 60, 120 days. The control group rats were injected with 1 ml of saline into lung, and killed after 120 days. The lungs of the rats were taken for pathological observation. Lung macrophages were extracted and counted, and their activity was detected by MTT. RT-qPCR was used to assess the relative contents of MyD88 mRNA and TRAF6 mRNA. Results: Silica dust inhalation led to infiltration of lung tissue cells, thickening the alveolar wall and destruction of alveolar structure. The longer the exposure to dust, the more obvious the results were. The number of macrophages in all experimental groups and activity in the 30 d, 60 d groups were significantly higher than that in the control group (P<0.05) . Among them, 30 d group had the largest number and the highest activity. Compared with the control group, the expression of MyD88 mRNA and TRAF6 mRNA of lung macrophages in rats increased in the experimental groups (P<0.05) , especially in the 60 d group. Conclusion: Silica dust inhalation can increase the expression of MyD88 and TRAF6 in macrophages, suggesting that silica dust can induce silicosis fibrosis by activating TLR/NF-κB signal pathway.


Assuntos
Fator 88 de Diferenciação Mieloide , Dióxido de Silício , Fator 6 Associado a Receptor de TNF , Animais , Poeira , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Fator 88 de Diferenciação Mieloide/efeitos dos fármacos , Fator 88 de Diferenciação Mieloide/metabolismo , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Dióxido de Silício/toxicidade , Fator 6 Associado a Receptor de TNF/efeitos dos fármacos , Fator 6 Associado a Receptor de TNF/metabolismo
8.
Molecules ; 24(10)2019 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-31109132

RESUMO

Myocardial infarction (MI) remains one of the major causes of mortality around the world. A possible mechanism involved in myocardial infarction is the engagement of Toll-like receptors (TLRs). This study was intended to discover the prospective cardioprotective actions of ß-caryophyllene, a natural sesquiterpene, to ameliorate isoproterenol (ISO)-induced myocardial infarction through HSP-60/TLR/MyD88/NFκB pathway. ß-Caryophyllene (100 or 200 mg/kg/day orally) was administered for 21 days then MI was induced via ISO (85 mg/kg, subcutaneous) on 20th and 21st days. The results indicated that ISO induced a significant infarcted area associated with several alterations in the electrocardiogram (ECG) and blood pressure (BP) indices and caused an increase in numerous cardiac indicators such as creatine phosphokinase (CPK), creatine kinase-myocardial bound (CK-MB), lactate dehydrogenase (LDH), and cardiac tropinine T (cTnT). In addition, ISO significantly amplified heat shock protein 60 (HSP-60) and other inflammatory markers, such as TNF-α, IL-Iß, and NFκB, and affected TLR2 and TLR4 expression and their adaptor proteins; Myeloid differentiation primary response 88 (MYD88), and TIR-domain-containing adapter-inducing interferon-ß (TRIF). On the other hand, consumption of ß-caryophyllene significantly reversed the infarcted size, ECG and BP alterations, ameliorated the ISO elevation in cardiac indicators; it also notably diminished HSP-60, and subsequently TLR2, TLR4, MYD88, and TRIF expression, with a substantial reduction in inflammatory mediator levels. This study revealed the cardioprotective effect of ß-caryophyllene against MI through inhibiting HSP-60/TLR/MyD88/NFκB signaling pathways.


Assuntos
Produtos Biológicos/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Substâncias Protetoras/farmacologia , Sesquiterpenos/farmacologia , Receptores Toll-Like/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Pressão Sanguínea/efeitos dos fármacos , Creatina Quinase/metabolismo , Eletrocardiografia/efeitos dos fármacos , Isoproterenol/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Ratos Sprague-Dawley
9.
Eur J Pharmacol ; 854: 347-353, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31039345

RESUMO

The cytokine storm includes a clinically heterogeneous set of life-threatening conditions that are manifested by extremely elevated serum cytokine levels and related symptoms (e.g., septic shock) and is devilishly mediated by Toll-like receptor (TLR) agonists in most situations. A tyrosine kinase inhibitor (TKIs), sunitinib, was screened in our group previously and showed antagonistic activity for cytokine release in a TLR7 stimulation model. In this paper, we further studied its mechanisms on interesting phenomena. In vitro, nearly all of the eleven TKIs decreased the TNF-α levels induced by the TLR7 agonist, especially sunitinib. Furthermore, sunitinib displayed potent inhibition of the cytokine levels triggered by several types of TLR ligands, including TLR3, TLR4, TLR7/8 and TLR9, in mouse spleen lymphocytes, mouse BMDCs and human PBMCs. The in vivo results showed that sunitinib efficiently depressed the LPS-induced cytokine storm, i.e., rapid and intense production of TNF-α and IL-6. Sunitinib further increased the survival time and decreased damage to mice. As for the immunosuppressive mechanisms of sunitinib, at least the PDGFR-activated ERK and p38 pathways were critical, although we could not rule out the possibility of other pathways being involved. In conclusion, our study demonstrated the inhibitory actions of TKIs on the cytokine storm induced by TLR ligands, primarily through PDGFR pathways, which could be potentially used to reduce cytokine storms in septic shock.


Assuntos
Citocinas/biossíntese , Sunitinibe/farmacologia , Receptores Toll-Like/metabolismo , Animais , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Fator 88 de Diferenciação Mieloide/metabolismo , Células RAW 264.7 , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores Toll-Like/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Vasc Med ; 24(4): 295-305, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31084431

RESUMO

Critical limb ischemia (CLI) is associated with skeletal muscle damage. However, the pathophysiology of the muscle damage is poorly understood. Toll-like receptors (TLR) have been attributed to play a role in ischemia-induced tissue damage but their role in skeletal muscle damage in CLI is unknown. TLR2 and TLR6 expression was found to be upregulated in skeletal muscle of patients with CLI. In vitro, ischemia led to upregulation of TLR2 and TLR6 by myotubes, and activation of the downstream TLR signaling pathway. Ischemia-induced activation of the TLR signaling pathway led to secretion of the pro-inflammatory cytokine interleukin-6 and muscle apoptosis, which were abrogated by neutralising TLR2 and TLR6 antibodies. Our study demonstrates that TLR2 and TLR6 are upregulated in ischemic muscle and play a role in ischemia-induced muscle damage. Thus, manipulating the TLR pathway locally may be of potential therapeutic benefit.


Assuntos
Apoptose , Mediadores da Inflamação/metabolismo , Isquemia/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 6 Toll-Like/metabolismo , Idoso , Animais , Estudos de Casos e Controles , Linhagem Celular , Estado Terminal , Feminino , Humanos , Interleucina-6/metabolismo , Isquemia/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/patologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Regulação para Cima
11.
Gene ; 707: 136-142, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31054361

RESUMO

Neural stem/progenitor cells (NSPCs) can enhance regeneration after spinal cord injury (SCI), but survival of transplanted cells remains poor. Understanding how NSPCs respond to the chemical mediators of secondary injury thus is essential for treating SCI. Thymosin ß4 (Tß4) has physiological functions that are highly relevant to SCI. We exposed NSPCs to oxidative stress and found reduced expression of Tß4 in H2O2-injured NSPCs. Using an MTT assay, we found that Tß4 dose dependently increased viability of the injured NSPCs. Tß4 also reversed the decreases of intracellular Ca2+ concentration and increases of lactate dehydrogenase in NSPCs induced by H2O2 treatment. H2O2 exposure increased NSPC apoptosis, which Tß4 decreased. In H2O2-induced NSPCs, ROS production and pro-inflammatory cytokines increased, and again, Tß4 reversed these effects. We investigated the toll-like receptor 4 (TLR4) and myeloid differentiation primary response 88 (MyD88) signaling pathway as an underlying mechanism in Tß4's protective effect on H2O2-exposed NSPCs. Our results showed that Tß4 reduced expression of TLR4 and MyD88. Moreover, H2O2-exposed NSPCs that were treated with the TLR4/MyD88 pathway inhibitor showed a reversal of all the effects caused by H2O2, similar to Tß4's effects. In conclusion, our study determined that Tß4 attenuated H2O2-induced oxidative stress injury in NSPCs via the TLR4/MyD88 pathway.


Assuntos
Células-Tronco Neurais/citologia , Transdução de Sinais , Traumatismos da Medula Espinal/metabolismo , Timosina/metabolismo , Animais , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Peróxido de Hidrogênio/efeitos adversos , Masculino , Fator 88 de Diferenciação Mieloide/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/metabolismo
12.
Int Immunopharmacol ; 72: 176-185, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30986645

RESUMO

Eph receptor tyrosine kinases have a wide range of biological functions and have gradually been recognized increasingly as key regulators of inflammation and injury diseases. Although previous studies suggested that EphA2 receptor may be involved in the regulation of inflammation and vascular permeability in injured lung, the detailed effects of EphA2 on LPS-induced acute lung injury (ALI) are still inadequate and the underlying mechanism remains poorly understood. In this study, we detected the effects of EphA2 antagonism on inflammation, pulmonary vascular permeability and oxidative stress in LPS-induced ALI and investigate the potential mechanism. Our results showed that EphA2 antagonism markedly inhibited the cytokines release and inflammatory cells infiltration in BALF, prevented the LPS-induced elevations of MPO activity and MDA level in lung tissues. Our study also found that EphA2 antagonism significantly decreased the wet/dry ratios, reduced the Evans blue albumin extravasation in lung tissues and obviously alleviated the LPS-induced increment of pulmonary vascular permeability. Mechanistically, EphA2 antagonism significantly increased the activation of Nrf2 along with its target antioxidant enzyme HO-1 and inhibited the expressions of TLR4/MyD88 in lung tissues and A549 alveolar epithelial cells. Furthermore, EphA2 antagonism dramatically inhibited the LPS-evoked activations of RhoA/ROCK in lung tissues. In conclusion, our data indicate that EphA2 receptor plays an essential role in LPS-induced ALI and EphA2 antagonism has protective effects against LPS-induced ALI via Nrf2/HO-1, TLR4/MyD88 and RhoA/ROCK pathways. These results suggest that antagonism of EphA2 may be an effective therapeutic strategy for the treatment of ALI.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Receptor EphA2/antagonistas & inibidores , Células A549 , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Anticorpos Monoclonais/farmacologia , Líquido da Lavagem Broncoalveolar/química , Heme Oxigenase (Desciclizante)/metabolismo , Humanos , Lipopolissacarídeos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Malondialdeído/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Ratos Sprague-Dawley , Receptor EphA2/imunologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo
13.
Fish Shellfish Immunol ; 90: 52-64, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31015066

RESUMO

Toll-interacting protein (Tollip) is a key negative regulator of TLR-mediated innate immune responses. The structure and function of Tollip have been well identified in mammals, but the information about Tollip is still limited in teleost fishes. In the present study, the homologue of Tollip was cloned from Japanese eel. It contained an open reading frame encoding a polypeptide of 276 amino acids which shared high identities with other homologues from different species. Multiple alignment of the amino acid sequence showed that the AjTollip protein has the typical conserved domains including an N-terminal Target of Myb1 (Tom1) binding domain (TBD), a central conserved 2 (C2) domain, and a C-terminal coupling of ubiquitin to endoplasmic reticulum degradation (CUE) domain. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed a broad expression for AjTollip in a wide range of tissues, with the highest expression in the liver, a relatively high expression in the spleen, kidney, gills, skin and intestine, and a low expression in the heart and muscle. The AjTollip expressions in the liver and kidney were significantly induced following injection with the bacterial mimic LPS, the viral mimic poly I:C, and Aeromonas hydrophila infection. In vitro, the AjTollip transcripts of Japanese eel liver cells were significantly enhanced by the treatment of LPS, poly I:C, CpG-DNA, and PGN or the stimulation of high concentration of Aeromonas hydrophila (1 × 107 cfu/mL and 1 × 108 cfu/mL). Subcellular localization study showed that AjTollip was mainly distributed in the cytoplasm in a condensed state. When AjTollip was co-transfected with AjMyD88 into HEK293 cells, the luciferase activities of NF-κB were significantly decreased compared with that of AjMyD88 single-transfection groups in natural state or under the stimulation of LPS and poly I:C. These results collectively suggested that AjTollip functions as a negative regulator of MyD88-dependent TLR signaling and plays an important role in fish defense against viral and bacterial infections.


Assuntos
Anguilla/genética , Anguilla/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Lipopolissacarídeos/farmacologia , Fator 88 de Diferenciação Mieloide/metabolismo , Filogenia , Poli I-C/farmacologia , Alinhamento de Sequência/veterinária , Transdução de Sinais/imunologia , Receptores Toll-Like/metabolismo
14.
Vet Microbiol ; 232: 128-136, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31030836

RESUMO

The interleukin-1 (IL-1) family of cytokines, particularly IL-1α and IL-1ß, are potent regulators of innate immunity that play key roles in host defense against infection, hence we evaluated the role of these cytokines in the control of brucellosis within RAW 264.7 cells. Marked expression and secretion of IL-1α and IL-1ß were observed during Brucella infection in macrophages. Blocking of IL-1α and IL-1ß reduced induction of IL-10, IL-1ß and TNF, and IL-6 and TNF, respectively. However, interference of IL-1α and not IL-1ß signaling notably augmented susceptibility of macrophages to Brucella infection which indicates that IL-1α is required for a downstream signaling cascade of innate immunity for efficient clearance of Brucella. This protection requires binding to interleukin-1 receptor (IL-1R) mediated by myeloid differentiation factor 88 (MyD88) signaling and associated with increased lysosomal-mediated killing and nitric oxide (NO) production. Expression of pro-inflammatory cytokines was observed to be mediated via NF-κB-p50, HIF-1α and CEBPA, but negatively controlled by CEBPB while transcription of some important phagolysosomal genes was regulated via CEBPA and c-Jun which indicates the important role of these transcription factors in the control of Brucella infection in macrophages via IL-1α signaling pathway.


Assuntos
Brucella abortus/patogenicidade , Interleucina-1alfa/imunologia , Macrófagos/imunologia , Óxido Nítrico/imunologia , Animais , Imunidade Inata , Interleucina-1alfa/genética , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Macrófagos/microbiologia , Camundongos , Viabilidade Microbiana , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Células RAW 264.7 , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia
15.
Nature ; 568(7752): 405-409, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944470

RESUMO

Interleukin (IL)-2 is a pleiotropic cytokine that is necessary to prevent chronic inflammation in the gastrointestinal tract1-4. The protective effects of IL-2 involve the generation, maintenance and function of regulatory T (Treg) cells4-8, and the use of low doses of IL-2 has emerged as a potential therapeutic strategy for patients with inflammatory bowel disease9. However, the cellular and molecular pathways that control the production of IL-2 in the context of intestinal health are undefined. Here we show, in a mouse model, that IL-2 is acutely required to maintain Treg cells and immunological homeostasis throughout the gastrointestinal tract. Notably, lineage-specific deletion of IL-2 in T cells did not reduce Treg cells in the small intestine. Unbiased analyses revealed that, in the small intestine, group-3 innate lymphoid cells (ILC3s) are the dominant cellular source of IL-2, which is induced selectively by IL-1ß. Macrophages in the small intestine produce IL-1ß, and activation of this pathway involves MYD88- and NOD2-dependent sensing of the microbiota. Our loss-of-function studies show that ILC3-derived IL-2 is essential for maintaining Treg cells, immunological homeostasis and oral tolerance to dietary antigens in the small intestine. Furthermore, production of IL-2 by ILC3s was significantly reduced in the small intestine of patients with Crohn's disease, and this correlated with lower frequencies of Treg cells. Our results reveal a previously unappreciated pathway in which a microbiota- and IL-1ß-dependent axis promotes the production of IL-2 by ILC3s to orchestrate immune regulation in the intestine.


Assuntos
Imunidade Inata/imunologia , Interleucina-2/imunologia , Intestinos/citologia , Intestinos/imunologia , Linfócitos T Reguladores/imunologia , Animais , Antígenos/administração & dosagem , Antígenos/imunologia , Doença de Crohn/imunologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Feminino , Microbioma Gastrointestinal/imunologia , Homeostase/imunologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-2/deficiência , Interleucina-2/metabolismo , Intestino Delgado/citologia , Intestino Delgado/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Proteína Adaptadora de Sinalização NOD2/deficiência , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Linfócitos T Reguladores/classificação , Linfócitos T Reguladores/metabolismo
16.
Fish Shellfish Immunol ; 89: 719-726, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30995543

RESUMO

Myeloid differentiation factor 88 (MyD88) links members of the toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) superfamily to the downstream activation of NF-κB as a "bridge" molecular in response to exogenous pathogen, but the function in spotted knifejaw (Oplegnathus. punctatus), a commercial fish in China, is still unknown. We present a functional analysis of spotted knifejaw MyD88 (OppMyD88) with a typical death domain (DD) at the N-terminus and a conservative Toll/IL-1R (TIR) domain at the C-terminus and suggest that MyD88 is important for the activation of TLR-mediated NF-κB with the synergy between domains. Subcellular localization showed that OppMyD88 was distributed in the cytoplasm in a condensed form. Tissues expression profiling analysis showed that OppMyD88 ubiquitously expressed in all tested tissues with the highest expression in the liver, as determined by real-time PCR. The expression of OppMyD88 significantly upregulated in the liver, spleen, kidney and gills within 120 h post Vibrio anguillarum infection. Moreover, we further confirmed that over-expressed OppMyD88 could also induce apoptosis. These results indicate that OppMyD88 might possess important roles in defense against microbial infection and other biological processes in spotted knifejaw similar to those in mammals, which will deepen our understandings in innate immunity of spotted knifejaw.


Assuntos
Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Fator 88 de Diferenciação Mieloide/genética , Perciformes/genética , Perciformes/imunologia , Transdução de Sinais/genética , Animais , Infecções Bacterianas/imunologia , Infecções Bacterianas/veterinária , Doenças dos Peixes/imunologia , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica/veterinária , Fator 88 de Diferenciação Mieloide/metabolismo
17.
Vet Res Commun ; 43(2): 77-89, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30863917

RESUMO

Ovine ruminal epithelial cells (ORECs) not only have a physical barrier function but also can secrete host defence peptides (HDPs), such as sheep ß-defensin-1 (SBD-1). As a feed additive, Saccharomyces cerevisiae can enhance the host's innate immunity. ß-glucan, a cell wall component of Saccharomyces cerevisiae, can stimulate innate immune responses and trigger the up-regulation of SBD-1 in ORECs. The signaling mechanisms involved in ß-glucan-induced SBD-1 expression are not completely understood. The aim of this study was to identify the receptors and intracellular pathways involved in the up-regulation of SBD-1 induced by ß-glucan. ORECs were cultured, and the regulatory mechanisms of ß-glucan-induced up-regulation of SBD-1 were detected using quantitative real-time PCR (qPCR), enzyme-linked immunosorbent assay (ELISA), and western blotting. TLR-2 and MyD88 knockdown or inhibition attenuated ß-glucan-induced SBD-1 expression. We also showed that inhibition of MAPK and NF-κB pathways significantly reduced ß-glucan-induced SBD-1 expression. These results demonstrate that ß-glucan-induced SBD-1 expression is TLR-2-MyD88-dependent and may be regulated by both MAPK and NF-κB pathways. Since NF-κB inhibition had a greater effect on the down-regulation of ß-glucan-induced SBD-1 expression, the NF-κB pathway may be the dominant signaling pathway involved in the regulation of defensin expression. Our studies demonstrate that ß-glucan-induced SBD-1 expression is mediated through the TLR-2-MyD88-NF-κB/MAPK pathway. Our results would contribute to the understanding of immunological modulations in the gastrointestinal tract triggered by probiotic yeast cell wall components.


Assuntos
Células Epiteliais/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno , Fator 88 de Diferenciação Mieloide , NF-kappa B , Receptores Toll-Like , beta-Defensinas/genética , beta-Glucanas/farmacologia , Animais , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Probióticos/farmacologia , Rúmen/efeitos dos fármacos , Saccharomyces cerevisiae/química , Ovinos , Receptores Toll-Like/metabolismo
18.
Cell Physiol Biochem ; 52(2): 212-224, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816669

RESUMO

BACKGROUND/AIMS: MIP-1α (macrophage inflammatory protein 1α)/CCL3 chemokine is associated with the adipose tissue inflammation in obesity. Both MIP-1α and free fatty acids are elevated in obesity/T2D. We asked if free fatty acid palmitate could modulate MIP1α expression in the human monocytic cells. METHODS: Human monocytic THP-1 cells and macrophages were stimulated with palmitate and TNF-α (positive control). MIP-1α expression was measured with real time RT-PCR, Flow Cytometry and ELISA. Signaling pathways were identified by using THP-1-XBlue™ cells, THP-1-XBlue™-defMyD cells, anti-TLR4 mAb and TLR4 siRNA. RESULTS: Our data show that palmitate induced significant increase in MIP1α production in monocytic THP-1 cells/macrophages. MIP-1α induction was significantly suppressed when cells were treated with anti-TLR4 antibody prior stimulation with palmitate. Using TLR4 siRNA, we further demonstrate that palmitate-induced MIP-1α expression in monocytic cells requires TLR4. Moreover, THP1 cells defective in MyD88, a major adaptor protein involved in TLR4 signaling, were unable to induce MIP-1α production in response to palmitate. Palmitate-induced MIP-1α expression was suppressed by inhibition of MAPK, NFkB and PI3K signaling pathways. In addition, palmitate-induced NF-κB/AP-1 activation was observed while production of MIP-1α. However, this activation of NF-κB/AP-1 was abrogated in MyD88 deficient cells. CONCLUSION: Overall, these results show that palmitate induces TLR4dependent MIP-1α expression requiring the MyD88 recruitment and activation of MAPK, NF-κB/AP-1 and PI3K signaling. It implies that the increased systemic levels of free fatty acid palmitate in obesity/T2D may contribute to metabolic inflammation through excessive production of MIP-1a.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Monócitos/metabolismo , Ácido Palmítico/farmacologia , Receptor 4 Toll-Like/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Macrófagos/patologia , Monócitos/patologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Células THP-1 , Receptor 4 Toll-Like/genética
19.
Gene ; 700: 85-95, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-30878390

RESUMO

MiR-155-3p, which is derived from the same pre-miRNA as miR-155-5p, the latter has been reported to be dysregulated in multiple tumor tissues and associated with clinicopathologic markers, tumor subtypes, and poor survival rates. However, the biological effects of miR-155-3p are rarely explored. In this study, we find that miR-155-3p was down-regulated in breast cancer and MYD88 was validated as the target for miR-155-3p. Moreover, miR-155-3p showed a negative effect on apoptosis, invasion and metastasis, reverses paclitaxel resistance by suppression of the corresponding target gene MYD88 in vitro and in vivo experiments. Taking together, our studies suggest that miR-155-3p, which serve as a negative regulatory mechanism for breast cancer development. The mechanism further complicates the regulatory network in human breast cancer.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/genética , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Regiões 3' não Traduzidas , Adulto , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Camundongos , Pessoa de Meia-Idade , Transplante de Neoplasias , Paclitaxel
20.
Immunity ; 50(3): 692-706.e7, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30824326

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a severe form of lung fibrosis with a high mortality rate. However, the etiology of IPF remains unknown. Here, we report that alterations in lung microbiota critically promote pulmonary fibrosis pathogenesis. We found that lung microbiota was dysregulated, and the dysregulated microbiota in turn induced production of interleukin-17B (IL-17B) during bleomycin-induced mouse lung fibrosis. Either lung-microbiota depletion or IL-17B deficiency ameliorated the disease progression. IL-17B cooperated with tumor necrosis factor-α to induce expression of neutrophil-recruiting genes and T helper 17 (Th17)-cell-promoting genes. Three pulmonary commensal microbes, which belong to the genera Bacteroides and Prevotella, were identified to promote fibrotic pathogenesis through IL-17R signaling. We further defined that the outer membrane vesicles (OMVs) that were derived from the identified commensal microbes induced IL-17B production through Toll-like receptor-Myd88 adaptor signaling. Together our data demonstrate that specific pulmonary symbiotic commensals can promote lung fibrosis by regulating a profibrotic inflammatory cytokine network.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/microbiologia , Interleucina-17/metabolismo , Pulmão/metabolismo , Pulmão/microbiologia , Microbiota/fisiologia , Animais , Bacteroides/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , Neutrófilos/metabolismo , Prevotella/metabolismo , Transdução de Sinais/fisiologia , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA