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1.
Medicine (Baltimore) ; 98(40): e17313, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577725

RESUMO

To investigate the impact of carriage of single nucleotide polymorphisms (SNPs) of the Toll-like receptor-4 (TLR4) and of autophagy-related gene 16-like-1 (ATG16L1) in preterm delivery (PTD).A prospective cohort of 145 pregnant women was studied. Women were prospectively followed-up until delivery. Genotyping for rs4986790 (Asp299Gly transition) and rs4986791 (Thr399Ile transition) of TLR4 and for rs2241880 of ATG16L1 was done by PCR-restriction fragment length polymorphism. The primary study endpoint was the impact of carriage of minor alleles of TLR4 on early PTD before gestational week 32. Associations with human chorionic gonadotrophin (hCG) were also analyzed. Peripheral blood mononuclear cells were isolated from 15 healthy women and stimulated for cytokine production.No difference in clinical characteristics was observed between women delivering full term and preterm. The frequency of early PTD was 25% among women carrying minor alleles of TLR4 and 6.8% among women carrying major alleles (P: .032). Odds ratios for PTD were 3.85 among women carrying the GG genotype of rs2241880 and major alleles of TLR4 and 0.26 among carriers of GG genotype and minor alleles of TLR4 (P: .030). The co-presence of GG genotype of rs2241880 and hCG above 70 U/L was an independent variable for PTD. Stimulated production of interleukin-6 was greater among women with GG genotypes of rs2241880.Minor alleles of SNPs of TLR4 predispose to early PTD. The GG genotype of rs2241880 of ATG16L1 is associated with PTD when hCG is supra-elevated.


Assuntos
Proteínas Relacionadas à Autofagia/genética , Nascimento Prematuro/genética , Receptor 4 Toll-Like/genética , Adulto , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Autofagia/fisiologia , Gonadotropina Coriônica/sangue , Citocinas/biossíntese , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Idade Gestacional , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Estudos Prospectivos
2.
Chem Biol Interact ; 314: 108844, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600484

RESUMO

Using data from Schink et al. (2018), a large number of herbal extracts were assessed for their capacity to induce pro- and anti-inflammatory effects based on TLR4 expression normalized for cell viability in two immune cell models (i.e., HeLa-TLR4 transfected reporter cell line, and THP-1 monocytes) applying seven concentrations (0.01-3.0%). The analysis revealed that 70-80% of the extracts satisfying the a priori entry criteria also satisfied a priori evaluative criteria for hormetic concentration responses. These findings demonstrate that a large proportion of herbal extracts display hormetic dose responses in immune cells, indicating that hormetic mechanisms mediate pro- and anti-inflammatory processes and may provide a means to guide optimal dosing strategies. The identification of doses eliciting only anti-inflammatory therapeutic activity as well as the use of dose-variable herbal extracts in the treatment of inflammatory diseases will be challenging.


Assuntos
Anti-Inflamatórios/farmacologia , Hormese/efeitos dos fármacos , Extratos Vegetais/química , Plantas Medicinais/química , Anti-Inflamatórios/química , Linhagem Celular , Células HeLa , Humanos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
3.
J Agric Food Chem ; 67(34): 9477-9491, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31429552

RESUMO

Lipopolysaccharide (LPS) is a bacterial endotoxin that induces intestine inflammation. Milk exosomes improve the intestine and immune system development of newborns. This study aims to establish the protective mechanisms of porcine milk exosomes on the attenuation of LPS-induced intestinal inflammation and apoptosis. In vivo, exosomes prevented LPS-induced intestine damage and inhibited (p < 0.05) LPS-induced inflammation. In vitro, exosomes inhibited (p < 0.05) LPS-induced intestinal epithelial cells apoptosis (23% ± 0.4% to 12% ± 0.2%). Porcine milk exosomes also decreased (p < 0.05) the LPS-induced TLR4/NF-κB signaling pathway activation. Furthermore, exosome miR-4334 and miR-219 reduced (p < 0.05) LPS-induced inflammation through the NF-κB pathway and miR-338 inhibited (p < 0.05) the LPS-induced apoptosis via the p53 pathway. Cotransfection with these three miRNAs more effectively prevented (p < 0.05) LPS-induced cell apoptosis than these miRNAs individual transfection. The apoptosis percentage in the group cotransfected with the three miRNAs (14% ± 0.4%) was lower (p < 0.05) than that in the NC miRNA group (28% ± 0.5%), and also lower than that in each individual miRNA group. In conclusion, porcine milk exosomes protect the intestine epithelial cells against LPS-induced injury by inhibiting cell inflammation and protecting against apoptosis through the action of exosome miRNAs. The presented results suggest that the physiological amounts of miRNAs-enriched exosomes addition to infant formula could be used as a novel preventative measure for necrotizing enterocolitis.


Assuntos
Apoptose , Células Epiteliais/citologia , Exossomos/metabolismo , MicroRNAs/metabolismo , Leite/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/metabolismo , Exossomos/genética , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , MicroRNAs/genética , NF-kappa B/genética , Transdução de Sinais , Suínos , Receptor 4 Toll-Like/genética , Proteína Supressora de Tumor p53/genética
4.
Life Sci ; 233: 116704, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31369761

RESUMO

AIMS: Doxorubicin, an anticancer drug, has a toxic effect on many tissues such as heart, pancreas, liver, kidney, and testis. The aim of current study is to investigate whether melatonin would be protective in doxorubicin-induced beta (ß) cell toxicity via HMGB1/TLR2/TLR4/MAPK/NF-қB signaling pathway. MAIN METHODS: Human pancreatic ß cell (1.1B4) was used in the present study. Four experimental groups were created as control, melatonin (10 µM), doxorubicin (2 µM) and the combination of melatonin with doxorubicin. Following 24-h treatment, Mitogen-activated protein kinase (MAPKs), Toll like receptors (TLRs) including TLR2 and TLR4, pro-and anti-apoptotic protein expression levels were determined by western blotting. Total antioxidant (TAS), oxidant status (TOS) and oxidative stress index (OSI) of the cells as well as superoxide dismutase (SOD) levels were determined. Active caspase-8 activity was measured and TUNEL staining was performed to study apoptotic pathways. Mitochondrial membrane potential (MMP), some protein expressions and F-actin distribution were analyzed. KEY FINDINGS: Doxorubicin caused to depolarize MMP, resulting in enhancing apoptosis by activation of caspase-8 via MAPKs/NF-кB pathway via elevation of TOS and decreasing TAS. Also, doxorubicin destroyed F-actin distribution and elevated TLR2 and some apoptotic proteins, including Bax. However, co-treatment of melatonin with doxorubicin could reverse depolarization of MMP and inhibition of apoptosis through MAPK/NF-кB signaling by decreasing TOS and increasing TAS. The co-treatment reversed the alternations of TLR2, TLR4, MAPKs and apoptotic protein expressions induced by doxorubicin. SIGNIFICANCE: Melatonin could be a good candidate against pancreatic ß cell toxicity-induced by doxorubicin through TLR2/TLR4/MAPK/NF-кB pathways.


Assuntos
Doxorrubicina/efeitos adversos , Células Secretoras de Insulina/efeitos dos fármacos , Melatonina/farmacologia , Substâncias Protetoras/farmacologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Antibióticos Antineoplásicos/efeitos adversos , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Proteína HMGB1/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , NF-kappa B/metabolismo , Oxidantes/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
J Agric Food Chem ; 67(36): 10079-10088, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31461286

RESUMO

Geraniin has been reported to possess potent anti-inflammatory properties and to modulate the macrophage polarization. This study sought to evaluate the protective effects and underlying mechanisms of geraniin on lipopolysaccharide (LPS)-induced neuroinflammation and neurobiological alternations as well as cognitive impairment. Daily intragastrical administration with geraniin (20 mg kg-1 day-1) for 14 days significantly prolonged the duration in the target quadrant (26.53 ± 2.03 versus 37.09 ± 3.27%; p < 0.05) and increased crossing-target number (1.93 ± 0.22 versus 3.08 ± 0.17; p < 0.01) in the probe test of LPS-treated mice. Geraniin also ameliorated LPS-elicited neural/synaptic impairments and decreased levels of LPS-induced Aß generation (p < 0.05), amyloid precursor protein (APP) (p < 0.05) and ß-site amyloid precursor protein cleavage enzyme 1 (BACE1) (p < 0.05). Furthermore, geraniin suppressed the production of pro-inflammatory cytokines, including tumor necrosis factor α (TNF-α) (9.85 ± 0.58 versus 5.20 ± 0.52 pg/mg of protein; p < 0.01), interleukin (IL)-1ß (16.31 ± 0.67 versus 8.62 ± 0.46 pg/mg of protein; p < 0.01), and IL-6 (12.12 ± 0.45 versus 7.43 ± 0.32 pg/mg of protein; p < 0.05), and inhibited glial cell activation. Moreover, geraniin effectively polarized the microglia toward an anti-inflammatory M2 phenotype. Further study revealed that geraniin targeted toll-like receptor 4 (TLR4)-mediated signaling and decreased the production of pro-inflammatory cytokines in BV-2 microglial cells. These results indicate that geraniin mitigates LPS-elicited neural/synaptic neurodegeneration, amyloidogenesis, neuroinflammation, and cognitive impairment and suggest geraniin as a therapeutic option for neuroinflammation-associated neurological disorders, such as Alzheimer's disease.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Glucosídeos/administração & dosagem , Taninos Hidrolisáveis/administração & dosagem , Receptor 4 Toll-Like/imunologia , Secretases da Proteína Precursora do Amiloide , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/imunologia , Animais , Ácido Aspártico Endopeptidases , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Disfunção Cognitiva/imunologia , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Neuroglia/efeitos dos fármacos , Neuroglia/imunologia , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
6.
Adv Clin Exp Med ; 28(8): 1087-1094, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31403268

RESUMO

BACKGROUND: There is evidence that suggests variation in gene encoding pattern recognition receptors, the essential components of innate immunity, might be associated with atopic diseases. However, results have been inconclusive. OBJECTIVES: The aim of the study was to determine the individual associations and possible interactive effects of the CD14 (cluster of differentiation 14), TLR4 (toll-like receptor 4) and TLR2 (toll-like receptor 2) polymorphisms on allergic diseases. MATERIAL AND METHODS: The CD14 C-159T, TLR4 +896A/G and TLR2 A-16934T polymorphisms were identified in 115 children aged from 6 to 17 years. All subjects were selected using a detailed questionnaire which included questions on symptoms and each one underwent skin prick testing. All single-nucleotide polymorphisms (SNPs) were determined using real-time polymerase chain reaction (PCR) assays. RESULTS: There was no statistically significant correlation between the 3 polymorphisms (CD14 C-159T, TLR4 +896A/G and TLR2/-16934A/T) and either asthma, allergic rhinitis or atopy. We observed that children who were heterozygous or homozygous for both the CD14/-159T and TLR2/-16934A alleles had a 4-fold lower risk for asthma than children who were carriers of the T allele of CD14 but non-carriers of the A allele of TLR2, and an almost 3-fold lower risk for asthma when compared to all other groups. Concerning allergic rhinitis, a similar trend was observed. In addition, the presence of at least 1 A allele in the TLR2/-16934 polymorphism reduced the risk for asthma and allergic rhinitis, but only in children who were homozygous for the common A allele in the TLR4 +896 polymorphism. CONCLUSIONS: Our study supports the idea that the CD14, TLR2 and TLR4 polymorphisms may not be directly involved in the development of atopic diseases. However, our results suggest that their impact on the risk of asthma and allergic rhinitis might be modulated by gene-gene interactions.


Assuntos
Asma , Epistasia Genética , Imunidade Inata , Polimorfismo de Nucleotídeo Único , Adolescente , Alelos , Asma/genética , Asma/imunologia , Criança , Predisposição Genética para Doença , Humanos , Receptores de Lipopolissacarídeos/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética
7.
Medicine (Baltimore) ; 98(26): e16029, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31261506

RESUMO

BACKGROUND: To study the occurrence and prognosis of acute respiratory distress syndrome (ARDS) using single nucleotide polymorphisms (SNPs) of TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci in the TLR4/NF-κB pathway. METHODS: Genotypes were analyzed for TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci. Plasma TNF-α and IL-6 levels and MyD88 mRNA expression in peripheral blood mononuclear cells (PBMCs) of 300 ARDS patients and 300 non-ARDS patients (control group) were examined. The patients were followed up for 60 days, and the prognosis outcome was recorded. RESULTS: The TNF-α rs1800629 locus A allele and the IL-6 rs1800796 locus G allele were found to be risk factors for ARDS (adjusted OR = 1.452, 95% CI: 1.211-1.689, P < .001 and adjusted OR = 1.205, 95% CI: 1.058-1.358, P = .005, respectively). The G allele at MyD88 rs7744 locus was a protective factor against ARDS (adjusted OR = 0.748, 95% CI: 0.631-0.876, P < .001). Compared with the other groups, homozygotes for TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 loci had higher expression levels, of which homozygotes for TNF-α rs1800629 and IL-6 rs1800796 loci had lower 60-day survival rates, while MyD88 rs7744 locus homozygotes had a higher 60-day survival rate. CONCLUSION: The effect of TNF-α rs1800629, IL-6 rs1800796, and MyD88 rs7744 SNPs on gene expression level is a likely cause of ARDS occurrence and poor prognosis.


Assuntos
NF-kappa B/genética , Polimorfismo de Nucleotídeo Único , Síndrome do Desconforto Respiratório do Adulto/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Biomarcadores/sangue , Feminino , Expressão Gênica/genética , Humanos , Interleucina-6/sangue , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/sangue , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/sangue , Prognóstico , RNA Mensageiro/sangue , Síndrome do Desconforto Respiratório do Adulto/sangue , Síndrome do Desconforto Respiratório do Adulto/diagnóstico , Síndrome do Desconforto Respiratório do Adulto/mortalidade , Transdução de Sinais , Análise de Sobrevida , Receptor 4 Toll-Like/sangue , Fator de Necrose Tumoral alfa/sangue
8.
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
9.
Gene ; 710: 114-121, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31153885

RESUMO

Mastitis impairs animal health and results in economic loss. Lipopolysaccharide (LPS) may cause immune response and inflammation in the bovine mammary gland. Hydrogen sulfide (H2S) is the third gasotransmitter that acts as an anti-inflammation regulator in many cells. Despite the importance of H2S in regulating inflammation, the effect and mechanism of exogenous H2S on LPS-induced inflammation in bovine mammary epithelial cells are unknown. In the present study, with NaHS as a donor of H2S, the bovine mammary epithelial cell line (MAC-T) was applied as an in vitro model to study the role of H2S on LPS-induced MAC-T cells. The results verified that the cell viability was diminished by LPS but restored by exogenous H2S at a physiologically relevant concentration (10 µM). Additionally, the production of H2S was mitigated in the LPS-induced MAC-T cells. Meanwhile, exogenous H2S decreased the intracellular ROS production and mRNA expression levels of the pro-inflammatory cytokines, TNF-α, IL-1ß, IL-8, and IL-6. Furthermore, exogenous H2S inhibited the mRNA expression of TLR4 and activation of NF-κB signaling pathway. In summary, exogenous H2S exerts anti-inflammatory effects through attenuating oxidative stress and blocking the TLR4/NF-κB pathway in the LPS-induced bovine mammary epithelial cells. Our findings might clarify new prophylactic approaches for mastitis.


Assuntos
Anti-Inflamatórios/farmacologia , Sulfeto de Hidrogênio/farmacologia , Lipopolissacarídeos/efeitos adversos , Glândulas Mamárias Animais/citologia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular , Citocinas/genética , Regulação para Baixo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/imunologia , NF-kappa B/genética , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
10.
Cell Physiol Biochem ; 53(1): 1-18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31162913

RESUMO

BACKGROUND/AIMS: Innate immune toll-like receptors (TLRs) are emerging as nutrient sensors. Oxidative stress in the adipose tissue in obesity acts as a critical early trigger of altered pathophysiology. TLR2/TLR4 adipose upregulation has been associated with insulin resistance in humans; however, it remains unclear whether oxidative stress can modulate expression of TLR2/4 and related immune-metabolic regulators (IRF3/5) in immune cells. We, therefore, assessed their expression along with proinflammatory cytokines in the human PBMC following induction of oxidative stress. METHODS: PBMC were isolated from blood of healthy donors using Ficoll-Paque method and cells were treated with H2O2 to induce oxidative stress. ROS was measured by DCFH-DA assay. Target gene and protein expression was determined using real-time RT-PCR and flow cytometry/confocal microscopy, respectively. TLR2/4 expression by H2O2 in presence of ROS-inhibitors or leptin/LPS/fatty acids was also assessed. Expression of phosphorylated/total ERK1/2, c-Jun, p38, and NF-κB was determined by western blotting. The data (mean±SEM) were compared using unpaired student's t-test or ANOVA; all P-values <0.05 were considered significant. RESULTS: TLR2/4 mRNA/protein expression was elevated by oxidative stress in PBMC compared to controls (P<0.001). This induction was abrogated by apocynin/N-acetyl cysteine treatments (P<0.01). H2O2-induced TLR2/4 gene expression was further enhanced by leptin, LPS, oleate, or palmitate (P<0.05). Oxidative stress also promoted expression of IRF3/5 and proinflammatory cytokines including IFN-γ, IL-1ß, IL-6, TNF-α, and MCP-1/CCL2. This oxidative stress in PBMC involved MAPK/NF-κB dependent signaling. CONCLUSION: Taken together, oxidative stress upregulates expression of TLR2/4, IRF3/5 and signature proinflammatory cytokines in PBMC, involving MAPK/NF-κB dependent signaling, all of which may have implications for metabolic inflammation.


Assuntos
Inflamação/genética , Estresse Oxidativo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Regulação para Cima , Células Cultivadas , Humanos , Inflamação/metabolismo , Fator Regulador 3 de Interferon/genética , Fatores Reguladores de Interferon/genética , Leucócitos Mononucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
PLoS Pathog ; 15(6): e1007871, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31226171

RESUMO

Infection of host cells by Toxoplasma gondii is an active process, which is regulated by secretion of microneme (MICs) and rhoptry proteins (ROPs and RONs) from specialized organelles in the apical pole of the parasite. MIC1, MIC4 and MIC6 assemble into an adhesin complex secreted on the parasite surface that functions to promote infection competency. MIC1 and MIC4 are known to bind terminal sialic acid residues and galactose residues, respectively and to induce IL-12 production from splenocytes. Here we show that rMIC1- and rMIC4-stimulated dendritic cells and macrophages produce proinflammatory cytokines, and they do so by engaging TLR2 and TLR4. This process depends on sugar recognition, since point mutations in the carbohydrate-recognition domains (CRD) of rMIC1 and rMIC4 inhibit innate immune cells activation. HEK cells transfected with TLR2 glycomutants were selectively unresponsive to MICs. Following in vitro infection, parasites lacking MIC1 or MIC4, as well as expressing MIC proteins with point mutations in their CRD, failed to induce wild-type (WT) levels of IL-12 secretion by innate immune cells. However, only MIC1 was shown to impact systemic levels of IL-12 and IFN-γ in vivo. Together, our data show that MIC1 and MIC4 interact physically with TLR2 and TLR4 N-glycans to trigger IL-12 responses, and MIC1 is playing a significant role in vivo by altering T. gondii infection competency and murine pathogenesis.


Assuntos
Moléculas de Adesão Celular/imunologia , Células Dendríticas/imunologia , Imunidade Inata , Macrófagos/imunologia , Proteínas de Protozoários/imunologia , Ácidos Siálicos/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Interleucina-12/imunologia , Camundongos , Camundongos Knockout , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Toxoplasmose Animal/genética
12.
Toxicol Lett ; 312: 34-44, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31059760

RESUMO

Inflammation is one of the factors that may increase the sensitivity of hepatic cells to acetaminophen (APAP) induced toxicity. To investigate the mechanisms, we exposed 3-dimensional (3D) Human Liver Microtissues, a co-culture of primary human hepatocytes (PHH) and Kupffer cells (KCs), to 0, 0.5 (low), 5 (median) and 10 mM (high dose) APAP for 24 h, with/without lipopolysaccharide (LPS). Microarray-technology was used to evaluate the transcriptome changes. In the presence of LPS, the median-dose of APAP is sufficient to inhibit the expression of respiratory chain- and antioxidant-related genes, suggesting the involvement of reactive oxygen species (ROS) and oxidative stress. Furthermore, the median- and high-dose of APAP inhibited the expression of Fc fragment receptor (FcγR)-coding genes, regardless of the presence of LPS. The toll-like receptor 4 (TLR4) expression, however, was continuously elevated after the LPS/APAP co-exposures, which may result in reduced KC-phagocytosis and unbalanced cytokine patterns. Compared to the treatment with LPS only, LPS/APAP co-exposures induced the production of interleukin (IL)-8, a pro-inflammatory cytokine, but suppressed the secretion of IL-6, a cytokine regulating hepatic regeneration, along with the increase in APAP dosages. In addition to the disrupted mitochondrial functions, the presence of LPS exacerbated APAP toxicity. These findings suggest that 3D Microtissues are a suitable model for the mechanistic exploration of inflammation-associated drug toxicity.


Assuntos
Citocinas/metabolismo , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Técnicas de Cultura de Tecidos/métodos , Acetaminofen/toxicidade , Analgésicos não Entorpecentes/toxicidade , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Macrófagos do Fígado/efeitos dos fármacos , Receptores de IgG/genética , Receptores de IgG/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Transcriptoma/efeitos dos fármacos
13.
Zhonghua Gan Zang Bing Za Zhi ; 27(4): 286-290, 2019 Apr 20.
Artigo em Chinês | MEDLINE | ID: mdl-31082340

RESUMO

Objective: To investigate TLR2 and TLR4 expressional situation on the surface of peripheral blood mononuclear cells (PBMC) in patients with hepatocellular carcinoma (HCC) and their relationship with small intestinal bacterial overgrowth (SIBO). Methods: Flow cytometry was used to detect TLR2 and TLR4 expressional situation on the surface of PBMC in 78 cases with HCC, 56 cases with cirrhosis and 33 healthy controls. Furthermore, lactose hydrogen breath test (LHBT) was used to detect small intestinal bacterial overgrowth. Results: Of the 78 cases with HCC, 56 cases (71.8%) were SIBO-positive, 23 cases (41.1%) were SIBO- positive in 56 cases with cirrhosis, and 1 (3.0%) was SIBO-positive in 33 healthy controls. The incidence of SIBO in HCC patients was higher than cirrhosis patients (χ(2) = 12.72, P < 0.05) and healthy controls (χ(2) = 41.18, P < 0.05). The expression levels of TLR2 and TLR4 in HCC patients (100.55 ± 24.22, 42.76 ± 15.96) were significantly higher than cirrhosis (67.42 ± 18.36, 24.38 ± 8.68)and healthy control group (33.06 ± 11.72, 12.52 ± 4.46) (P < 0.05). Furthermore, the expression levels of TLR2 and TLR4 in SIBO-positive patients (108.75 ± 20.40, 48.1 ± 14.98) were higher than SIBO-negative patients (79.67 ± 20.60, 28.62 ± 7.36) (P < 0.05). Conclusion: The expression of TLR2 and TLR4 and the incidence of SIBO in HCC patients are significantly higher than cirrhosis and healthy control group. Moreover, the high expressions of TLR2 and TLR4 in SIBO-positive HCC patients may promote the development of HCC.


Assuntos
Bactérias/isolamento & purificação , Carcinoma Hepatocelular/metabolismo , Leucócitos Mononucleares/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Receptor 2 Toll-Like/biossíntese , Receptor 4 Toll-Like/biossíntese , Infecções Bacterianas/sangue , Infecções Bacterianas/epidemiologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , China/epidemiologia , Humanos , Incidência , Leucócitos Mononucleares/patologia , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Receptor 2 Toll-Like/sangue , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/sangue , Receptor 4 Toll-Like/genética
14.
Medicine (Baltimore) ; 98(19): e15583, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31083239

RESUMO

The study was designed to reveal the relationship of toll-like receptor 4 (TLR4, rs1927914 and rs1927907) polymorphisms with risk of age-related macular degeneration (AMD), as well as the adjustment of this association by some environmental and lifestyle factors in Chinese Han population.TLR4 polymorphisms were genotyped by polymerase chain reaction-restricted fragment length polymorphisms and direct sequencing method in 138 AMD patients and 146 healthy controls. Genotype distribution in the control group was checked with Hardy-Weinberg equilibrium. Association of TLR4 polymorphisms and AMD risk was evaluated by χ test and adjusted by age and sex, smoking and drinking. Odds ratio (OR) with 95% confidence interval (95% CI) was used to represent the association strength. Logistic regressive analysis was used to calculate the adjusted OR values.CC genotype of rs1927914 had significantly lower frequency in AMD patients (P = .010), indicated a negative association with AMD risk (crude: OR = 0.358, 95% CI = 0.162-0.791; adjusted: OR = 0.355, 95% CI = 0.160-0.789). C allele of rs1927914 might decrease the susceptibility of AMD (crude: OR = 0.698, 95% CI = 0.497-0.982; adjusted: OR = 0.698, 95% CI = 0.495-0.984). No significant association has been discovered between TLR4 rs1927907 polymorphism and AMD susceptibility. Strong linkage disequilibrium existed between rs1927914 and rs1927907 polymorphisms. C-C haplotype was negatively associated with AMD risk (OR = 0.242, 95% CI = 0.121-0.485; OR = 0.242, 95% CI = 0.120-0.488).CC genotype and C allele of rs1927914 were significantly associated with the decreased AMD susceptibility.


Assuntos
Predisposição Genética para Doença , Degeneração Macular/genética , Polimorfismo de Nucleotídeo Único , Receptor 4 Toll-Like/genética , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Haplótipos , Humanos , Desequilíbrio de Ligação , Degeneração Macular/epidemiologia , Masculino , Polimorfismo de Fragmento de Restrição
15.
Cell Mol Life Sci ; 76(18): 3667-3678, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062071

RESUMO

Cardiolipins (CLs) are tetra-acylated diphosphatidylglycerols found in bacteria, yeast, plants, and animals. In healthy mammals, CLs are unsaturated, whereas saturated CLs are found in blood cells from Barth syndrome patients and in some Gram-positive bacteria. Here, we show that unsaturated but not saturated CLs block LPS-induced NF-κB activation, TNF-α and IP-10 secretion in human and murine macrophages, as well as LPS-induced TNF-α and IL-1ß release in human blood mononuclear cells. Using HEK293 cells transfected with Toll-like receptor 4 (TLR4) and its co-receptor Myeloid Differentiation 2 (MD2), we demonstrate that unsaturated CLs compete with LPS for binding TLR4/MD2 preventing its activation, whereas saturated CLs are TLR4/MD2 agonists. As a consequence, saturated CLs induce a pro-inflammatory response in macrophages characterized by TNF-α and IP-10 secretion, and activate the alternative NLRP3 inflammasome pathway in human blood-derived monocytes. Thus, we identify that double bonds discriminate between anti- and pro-inflammatory properties of tetra-acylated molecules, providing a rationale for the development of TLR4 activators and inhibitors for use as vaccine adjuvants or in the treatment of TLR4-related diseases.


Assuntos
Cardiolipinas/farmacologia , Macrófagos/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Ligação Competitiva , Cardiolipinas/química , Cardiolipinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CXCL10/metabolismo , Células HEK293 , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Antígeno 96 de Linfócito/genética , Antígeno 96 de Linfócito/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Monócitos/citologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
16.
Food Funct ; 10(5): 2894-2905, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31070610

RESUMO

Maca protein isolate (MPI) was extracted from maca root, and its physicochemical and functional properties, and the secondary structure and immunomodulatory activity of its major protein component, MMP, were investigated. The MPI lacked essential amino acids compared with soybean protein isolate (SPI) and casein, but was rich in cysteine and proline. The MPI had rich free sulfhydryl (20.6 µmol g-1), and its surface hydrophobicity (H0, 812.4), oil absorption capacity (7.4 g g-1), foaming capacity (100%) and emulsifying activity (58.2 m2 g-1) were higher than that of SPI. However, the thermal stability (Td, 87.4 °C), foaming stability (75%) and emulsifying stability (26.3 min) of the MPI were weaker than that of the SPI. MMP was a pentamer with a molecular weight of 22 kDa and rich in ß-sheets. MMP could significantly enhance the phagocytic capacity and promote the NO, TNF-α and IL-6 secretion of RAW 264.7 cells, involving toll-like receptor 4 and complement receptor 3 mainly.


Assuntos
Fatores Imunológicos/química , Lepidium/química , Proteínas de Plantas/química , Animais , Interações Hidrofóbicas e Hidrofílicas , Fatores Imunológicos/farmacologia , Interleucina-6/genética , Interleucina-6/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Peso Molecular , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Estrutura Secundária de Proteína , Células RAW 264.7 , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
17.
Nutrients ; 11(5)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035540

RESUMO

Natural polysaccharides, particularly galactomannans, are potential candidates for treatment of alcoholic liver diseases (ALD). However, applications are restricted due to the physicochemical properties associated with the high molecular weight. In this work, guar gum galactomannans were partially hydrolyzed by ß-mannanase, and the molecular mechanisms of hepatoprotective effects were elucidated both in vitro and in vivo. Release of lactate dehydrogenase and cytochrome C were attenuated by partially hydrolyzed guar gum (PHGG) in HepG2 cells, due to protected cell and mitochondrial membrane integrity. PHGG co-administration decreased serum amino transaminases and cholinesterase levels of acute alcohol intoxicated mice, while hepatic pathologic morphology was depleted. Activity of superoxide dismutase, catalase, and glutathione peroxidase was recovered to 198.2, 34.5, 236.0 U/mg protein, respectively, while malondialdehyde level was decreased by 76.3% (PHGG, 1000 mg/kg∙day). Co-administration of PHGG induced a 4.4-fold increment of p-AMPK expression, and lipid metabolism was mediated. PHGG alleviated toll-like-receptor-4-mediated inflammation via the signaling cascade of MyD88 and IκBα, decreasing cytokine production. Moreover, mediated expression of Bcl-2 and Bax was responsible for inhibited acute alcohol-induced apoptosis with suppressed cleavage of caspase 3 and PARP. Findings gained suggest that PHGG can be used as functional food supplement for the treatment of acute alcohol-induced liver injury.


Assuntos
Etanol/toxicidade , Galactanos/química , Galactanos/farmacologia , Hepatopatias Alcoólicas/prevenção & controle , Mananas/química , Mananas/farmacologia , Gomas Vegetais/química , Gomas Vegetais/farmacologia , Animais , Apoptose/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Inflamação/metabolismo , Peroxidação de Lipídeos , Potencial da Membrana Mitocondrial , Camundongos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
18.
Int J Oncol ; 54(6): 2179-2188, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31081044

RESUMO

Toll­like receptor 4 (TLR4), a key regulator of the innate immune system, is expressed not only in immune cells, but also in a number of cancer cells. A biological role for TLR4 in cutaneous squamous cell carcinoma (SCC), however, is unclear. In this study, we first examined TLR4 expression and localization in cases of SCC, actinic keratosis (AK) and Bowen's disease (BD) by immunohistochemistry. TLR4 expression was significantly higher in the SCC than in the AK or BD tissues. We then determined the TLR4 expression level in vivo, in 3 histological subtypes of SCC. TLR4 expression in poorly differentiated SCC was significantly lower compared with that of the moderately and well­differentiated type. In addition, the CD44 immunoreactivity tended to be high in the cell membrane of poorly differentiated SCC. Of note, poorly differentiated SCC is a risk factor of unfavorable outcomes in affected patients. We then assessed the biological role of TLR4 in HSC­1 and HSC­5 SCC cells and HaCaT human keratinocytes. TLR4 knockdown by transfection with siRNA accelerated HSC­1 and HaCaT cell migration and invasion compared to the control siRNA­transfected cells. TLR4 knockdown resulted in an increased CD44 expression and in an enhanced filopodia protrusion formation, particularly in HSC­1. On the whole, these results suggest that a reduced TLR4 expression enhances the malignant features in SCC cases and cultured SCC cell lines. TLR4 may thus play an anti­tumor role in cutaneous SCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Regulação para Baixo , Neoplasias Cutâneas/patologia , Receptor 4 Toll-Like/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Cutâneas/metabolismo , Receptor 4 Toll-Like/genética
19.
Gene ; 708: 1-9, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31082501

RESUMO

OBJECTIVES: Toll-like receptor 4 (TLR4) is known to be involved in the innate immunity and inflammatory responses that plays a crucial role in the pathogenesis of coronary artery disease (CAD). This study aimed to examine the potential relationship of TLR4 polymorphisms and serum TLR4 protein levels and the risk of CAD in the ethnic Zhuang population of China. METHODS: 1171 serum samples were collected from Zhuang patients, including 556 CAD cases (≥50% luminal stenosis of any coronary vessel) and 615 normal healthy controls (subjects with no luminal stenosis in coronary arteries). Detection of TLR4 polymorphisms was by single base extension polymerase chain reaction (Snapshot PCR) and DNA sequencing (rs11536879A/G and rs11536889G/C) gene sequence in all subjects. Serum TLR4 protein concentrations was measured by ELISA. RESULTS: There are significant differences in the allele and genotype frequencies of TLR4 gene rs11536889 between Chinese Zhuang CAD patients and controls, especially in the males. Male carriers of rs11536879 andrs11536889 variant alleles show an increased risk of CAD compared to non-carriers. Serum TLR4 protein levels of CAD patients are higher than controls and the levels tended to increase with the number of coronary artery lesions. Serum TLR4 protein levels of CAD patients showed no correlation with rs11536879 and rs11536889 polymorphisms. CONCLUSIONS: The rs11536879 and rs11536889 polymorphisms of TLR4 gene and serum TLR4 protein levels may contribute to the occurrence and development of CAD. However, the rs11536879 and rs11536889 polymorphisms have no significant effects on the expression of serum TLR4 protein in Zhuang patients with CAD.


Assuntos
Doença da Artéria Coronariana/genética , Predisposição Genética para Doença , Receptor 4 Toll-Like/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , China , Doença da Artéria Coronariana/sangue , Grupos Étnicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Receptor 4 Toll-Like/sangue
20.
Food Funct ; 10(6): 3262-3271, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31089650

RESUMO

Polysaccharides are closely associated with immune regulation. In this study, the aim was to investigate the effect of polysaccharides from Cordyceps gunnii mycelia (PPS) in cyclophosphamide (CTX)-induced immunodeficient mice. Compared with the CTX-induced immunosuppressed mice, the spleen and thymus indexes in mice with orally administered PPS were significantly increased, body weight loss was alleviated, and the natural killer (NK) cytotoxicity and proliferative activities of the lymphocytes were elevated. The recovery of peripheral white blood cells, red blood cells, hemoglobins and platelets was accelerated. Furthermore, the results from ELISA showed that PPS could up-regulate the serum levels of IL-2, IL-12, IFN-γ and IgG, and reduce the level of TGF-ß. Histopathological analysis of the spleen revealed the protective effect of PPS against CTX-induced immunosuppression. Western blotting results showed that PPS possessed immunomodulatory activity via TLR4/TRAF6/NF-κB signalling pathways. Finally, the intestinal absorption of PPS was poor, as detected in the Caco-2 transwell system. Taken together, these findings suggest that PPS plays a crucial role in protection against immunosuppression in cyclophosphamide-treated mice and could be a potential candidate for use in immune therapy regimens.


Assuntos
Cordyceps/química , Doenças do Sistema Imunitário/prevenção & controle , Fatores Imunológicos/administração & dosagem , Polissacarídeos/administração & dosagem , Fator 6 Associado a Receptor de TNF/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Ciclofosfamida/efeitos adversos , Feminino , Humanos , Doenças do Sistema Imunitário/induzido quimicamente , Doenças do Sistema Imunitário/imunologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Micélio/química , NF-kappa B/genética , NF-kappa B/imunologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Fator 6 Associado a Receptor de TNF/genética , Receptor 4 Toll-Like/genética
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