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1.
Nature ; 584(7820): 286-290, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760002

RESUMO

The histone deacetylases (HDACs) are a superfamily of chromatin-modifying enzymes that silence transcription through the modification of histones. Among them, HDAC3 is unique in that interaction with nuclear receptor corepressors 1 and 2 (NCoR1/2) is required to engage its catalytic activity1-3. However, global loss of HDAC3 also results in the repression of transcription, the mechanism of which is currently unclear4-8. Here we report that, during the activation of macrophages by lipopolysaccharides, HDAC3 is recruited to activating transcription factor 2 (ATF2)-bound sites without NCoR1/2 and activates the expression of inflammatory genes through a non-canonical mechanism. By contrast, the deacetylase activity of HDAC3 is selectively engaged at ATF3-bound sites that suppress Toll-like receptor signalling. Loss of HDAC3 in macrophages safeguards mice from lethal exposure to lipopolysaccharides, but this protection is not conferred upon genetic or pharmacological abolition of the catalytic activity of HDAC3. Our findings show that HDAC3 is a dichotomous transcriptional activator and repressor, with a non-canonical deacetylase-independent function that is vital for the innate immune system.


Assuntos
Histona Desacetilases/metabolismo , Inflamação/genética , Inflamação/metabolismo , Fator 2 Ativador da Transcrição/metabolismo , Fator 3 Ativador da Transcrição/metabolismo , Animais , Biocatálise , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Masculino , Camundongos , Correpressor 1 de Receptor Nuclear , Correpressor 2 de Receptor Nuclear , Proteínas Repressoras/metabolismo , Transcrição Genética/efeitos dos fármacos
2.
Nat Commun ; 11(1): 3816, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732870

RESUMO

Detection of microbial components such as lipopolysaccharide (LPS) by Toll-like receptor 4 (TLR4) on macrophages induces a robust pro-inflammatory response that is dependent on metabolic reprogramming. These innate metabolic changes have been compared to aerobic glycolysis in tumour cells. However, the mechanisms by which TLR4 activation leads to mitochondrial and glycolytic reprogramming are unknown. Here we show that TLR4 activation induces a signalling cascade recruiting TRAF6 and TBK-1, while TBK-1 phosphorylates STAT3 on S727. Using a genetically engineered mouse model incapable of undergoing STAT3 Ser727 phosphorylation, we show ex vivo and in vivo that STAT3 Ser727 phosphorylation is critical for LPS-induced glycolytic reprogramming, production of the central immune response metabolite succinate and inflammatory cytokine production in a model of LPS-induced inflammation. Our study identifies non-canonical STAT3 activation as the crucial signalling intermediary for TLR4-induced glycolysis, macrophage metabolic reprogramming and inflammation.


Assuntos
Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Expressão Gênica , Glicólise/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/genética , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição STAT3/genética , Serina/genética , Serina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 4 Toll-Like/genética
3.
Arterioscler Thromb Vasc Biol ; 40(9): 2265-2278, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32673525

RESUMO

OBJECTIVE: Macrophages are immune cells, capable to remodel the extracellular matrix, which can harbor extracellular DNA incorporated into neutrophil extracellular traps (NETs). To study the breakdown of NETs we studied the capability of macrophage subsets to degrade these structures in vitro and in vivo in a murine thrombosis model. Furthermore, we analyzed human abdominal aortic aneurysm samples in support of our in vitro and in vivo results. Approach and Results: Macrophages were seeded onto blood clots or isolated NETs and polarized. All macrophages were capable to degrade NETs. For initial breakdown, macrophages relied on extracellular deoxyribonucleases. Proinflammatory polarization enhanced NET degradation. The boost in degradation was because of increased macropinocytosis, as inhibition by imipramine diminished their NET breakdown. Inhibition of macropinocytosis in a murine thrombosis model led to increased NET burden and reduced thrombus resolution in vivo. When analyzing abdominal aortic aneurysm samples, macrophage density furthermore corresponded negatively with the amount of local NETs in the intraluminal thrombi as well as in the vessel wall, as increased macrophage density was associated with a reduction in NET burden. CONCLUSIONS: We provide evidence that macrophages degrade NETs by extracellular predigestion and subsequent uptake. Furthermore, we show that proinflammatory macrophages increase NET degradation through enhanced macropinocytosis, priming them for NET engulfment. Based on our findings, that inhibition of macropinocytosis in mice corresponded to increased NET amounts in thrombi and that local macrophage density in human abdominal aortic aneurysm is negatively associated with surrounding NETs, we hypothesize, that macrophages are able to degrade NETs in vivo.


Assuntos
Endodesoxirribonucleases/metabolismo , Armadilhas Extracelulares/metabolismo , Ativação de Macrófagos , Macrófagos/enzimologia , Neutrófilos/metabolismo , Pinocitose , Animais , Aneurisma da Aorta Abdominal/metabolismo , Células Cultivadas , Desoxirribonuclease I/metabolismo , Desoxirribonucleases/metabolismo , Modelos Animais de Doenças , Exodesoxirribonucleases/metabolismo , Feminino , Humanos , Imipramina/farmacologia , Interferon gama/farmacologia , Interleucina-13/farmacologia , Interleucina-4/farmacologia , Cinética , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Musculares/metabolismo , Fagocitose , Fenótipo , Fosfoproteínas/metabolismo , Pinocitose/efeitos dos fármacos , Veia Cava Inferior/metabolismo , Trombose Venosa/metabolismo
4.
PLoS One ; 15(7): e0236300, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32702056

RESUMO

Breadfruit is a traditional staple crop from Pacific islands with the potential to improve worldwide food security and mitigate diabetes. Flour produced from breadfruit is a gluten-free, low glycemic index, nutrient dense and complete protein option for modern foods but basic scientific knowledge of health impacts of a breadfruit-based diet in animals and humans was lacking. We designed a series of studies to provide basic and fundamental data on impacts of a breadfruit-based diet through an in vitro and in vivo model. Cooked breadfruit flour was digested through a multi-stage enzyme digestion model to estimate protein digestibility in comparison to wheat flour. Breadfruit protein was found to be easier to digest than wheat protein in the enzyme digestion model. The flour digestions were applied to Caco-2 cells to test the cytotoxicity and to measure the immunogenicity through cytokine expression. No significant differences were observed for immune factors and cytokines (IL-4, IL-10, IL-8, TNF-α, IFN-γ) on Caco-2 cells between the breadfruit and wheat groups. A breadfruit-based rodent chow was formulated by substitution of all of the wheat in the standard formulation with breadfruit. The diets were isocaloric, nutrient equivalent and used to feed male and female C57BL/6 mice for 21 days. No sign of malnutrition, discomfort, illness or death was observed among the mice because of the diet. The histology and the cytokine expression of the mice ileum from both groups were analyzed and showed similar results. The expression of major bacteria was measured in the colon and showed similar results. Mice fed the breadfruit diet had a significantly higher growth rate and body weight than standard diet fed mice. No negative health outcomes were observed in studies with in vitro or in vivo models and breadfruit flour is a healthy alternative to other starches for modern foods.


Assuntos
Artocarpus/química , Farinha , Abastecimento de Alimentos , Alimentos , Animais , Composição Corporal/efeitos dos fármacos , Células CACO-2 , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Dieta , Fezes/química , Humanos , Íleo/efeitos dos fármacos , Íleo/patologia , Interleucina-1beta/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Minerais/análise , Óxido Nítrico Sintase Tipo II/metabolismo
5.
Exp Parasitol ; 217: 107948, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32698076

RESUMO

Immunomodulation is an emerging concept to combat infection in recent years. Immunomodulators like arabinosylated-lipoarabinomannan (Ara-LAM) and glycyrrhizic-acid (GA) possess anti-leishmanial property, whereas sodium-antimony-gluconate (SAG) is still considered as the first choice for chemotherapy against leishmaniasis. During infection, invasion of Leishmania donovani needs the potential requirement of Ca2+, which is further responsible for apoptosis in intracellular amastigotes. However, suppression of elevated intracellular calcium by the activation of plasma-membrane-calcium-ATPase (PMCA4) facilitates survival of L. donovani in the host. In the present study, SAG, Ara-LAM, and GA were found to evoke significant increase in intracellular Ca2+ in L. donovani infected macrophages by inhibiting PMCA4. Moreover, PMCA4 inhibition by TFP or PMCA4 siRNA elevated the level of PKCß, whereas calcium-independent upregulation of PKCζ remained unchanged in infected macrophages. Furthermore, application of immunomodulators in infected macrophages resulted in down-regulation of PKCζ, conversion of anti-inflammatory to pro-inflammatory cytokines and inhibition of PMCA4. Plasma membrane-associated ceramide which is known to be elevated during leishmaniasis, triggered upregulation of PMCA4 via PKCζ activation. Interestingly, immunomodulators attenuated ceramide generation, which resulted into reduced PKCζ activation leading to the decreased PMCA expression in infected macrophages. Therefore, our study elucidated the efficacy of SAG, Ara-LAM, and GA in the reduction of parasite burden in macrophages by suppressing PMCA activation through inhibition of ceramide mediated upregulation of PKCζ.


Assuntos
Antiprotozoários/uso terapêutico , ATPases Transportadoras de Cálcio/sangue , Membrana Celular/enzimologia , Fatores Imunológicos/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Animais , Gluconato de Antimônio e Sódio/farmacologia , Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/farmacologia , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Ceramidas/metabolismo , Meios de Cultura Livres de Soro , Densitometria , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Ácido Glicirrízico/farmacologia , Ácido Glicirrízico/uso terapêutico , Imipramina/farmacologia , Immunoblotting , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/uso terapêutico , Macrófagos/fisiologia , Camundongos , RNA de Protozoário/genética , RNA de Protozoário/isolamento & purificação , RNA Interferente Pequeno/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Reversa , Transfecção
6.
Anticancer Res ; 40(8): 4681-4685, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727792

RESUMO

BACKGROUND/AIM: The functions of macrophages change in response to environmental factors such as lipopolysaccharide (LPS). LPS derived from Pantoea agglomerans (LPSp) is involved in macrophage activation and tissue repair when administered dermally. LPSp-activated macrophages may be useful for restoring and maintaining homeostasis of the skin. MATERIALS AND METHODS: Phorbol myristate acetate-treated human monocytes (THP-1 cells) were activated with LPSp. The medium of LPSp-activated THP-1 cells was added to normal human dermal fibroblasts (NHDF cells). After 24 h, the expression of hyaluronan (HA) synthase (HAS)2, hyaluronidase (HYAL)1, and tropoelastin in NHDF cells was analyzed using quantitative real-time PCR. RESULTS: The expression of HAS2 and tropoelastin was significantly increased, but that of HYAL1 was significantly decreased. It was demonstrated that the abilities of HA and elastin synthesis in NHDF cells increased through LPSp-activated THP-1 cells. CONCLUSION: LPSp-activated macrophages may be useful for enhancing the abilities of HA and elastin synthesis in fibroblasts, subsequently improving dysfunction and reducing various age-related disorders.


Assuntos
Elastina/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ácido Hialurônico/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Linhagem Celular , Humanos , Ativação de Macrófagos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Pantoea/metabolismo , Fagocitose/efeitos dos fármacos , Células Th1
7.
Nat Commun ; 11(1): 3459, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651360

RESUMO

Hepatic amebiasis, predominantly occurring in men, is a focal destruction of the liver due to the invading protozoan Entamoeba histolytica. Classical monocytes as well as testosterone are identified to have important functions for the development of hepatic amebiasis in mice, but a link between testosterone and monocytes has not been identified. Here we show that testosterone treatment induces proinflammatory responses in human and mouse classical monocytes. When treated with 5α-dihydrotestosterone, a strong androgen receptor ligand, human classical monocytes increase CXCL1 production in the presence of Entamoeba histolytica antigens. Moreover, plasma testosterone levels of individuals undergoing transgender procedure correlate positively with the TNF and CXCL1 secretion from their cultured peripheral blood mononuclear cells following lipopolysaccharide stimulation. Finally, testosterone substitution of castrated male mice increases the frequency of TNF/CXCL1-producing classical monocytes during hepatic amebiasis, supporting the hypothesis that the effects of androgens may contribute to an increased risk of developing monocyte-mediated pathologies.


Assuntos
Androgênios/farmacologia , Quimiocina CXCL1/metabolismo , Animais , Quimiocina CCL2/metabolismo , Quimiocinas/metabolismo , Di-Hidrotestosterona/farmacologia , Entamoeba histolytica/química , Voluntários Saudáveis , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
8.
Int J Nanomedicine ; 15: 4125-4138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606668

RESUMO

Purpose: To investigate the effect and mechanism of macrophage membrane-coated nanoparticles (M-NPs) on hepatic ischemia-reperfusion injury (I/RI) caused by orthotopic liver transplantation. In addition, the advantages of TLR4+/M-NPs compared to M-NPs are discussed. Materials and Methods: We prepared biomimetic M-NPs and identified their characteristics. M-NPs were injected into an SD rat model of orthotopic liver transplantation, and the anti-inflammatory and anti-I/RI activities of M-NPs were studied in vivo and in vitro. In addition, we overexpressed macrophage membrane Toll-like receptor 4 (TLR4) in vitro and prepared TLR4+/M-NPs. Then, we assessed the characteristics and advantages of TLR4+/M-NPs. Results: The M-NPs neutralized endotoxin, inhibited the overactivation of Kupffer cells (KCs) and suppressed the secretion of inflammatory factors by inhibiting the endotoxin-mediated TLR4/MyD88/IRAK1/NF-κB signaling pathway. In an orthotopic liver transplantation model in SD rats, M-NPs showed significant therapeutic efficacy by neutralizing endotoxin and suppressing the secretion of inflammatory factors. Moreover, overexpression of TLR4 on the macrophage membrane by using a TLR4+-plasmid in vitro effectively reduced the amount of M-NPs needed to neutralize an equivalent dose of endotoxin, reducing the potential risks of NP overuse. Conclusion: This study indicates that M-NPs can effectively alleviate I/RI induced by liver transplantation.


Assuntos
Membrana Celular/metabolismo , Endotoxinas/metabolismo , Transplante de Fígado/efeitos adversos , Fígado/irrigação sanguínea , Macrófagos/metabolismo , Nanopartículas/química , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/terapia , Animais , Anti-Inflamatórios/farmacologia , Fluorescência , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Nanopartículas/ultraestrutura , Células RAW 264.7 , Ratos Sprague-Dawley , Receptor 4 Toll-Like/metabolismo
9.
PLoS One ; 15(7): e0235518, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614928

RESUMO

Interruption of the programmed death 1 (PD-1) / programmed death ligand 1 (PD-L1) pathway is an established and effective therapeutic strategy in human oncology and holds promise for veterinary oncology. We report the generation and characterization of monoclonal antibodies specific for canine PD-1 and PD-L1. Antibodies were initially assessed for their capacity to block the binding of recombinant canine PD-1 to recombinant canine PD-L1 and then ranked based on efficiency of binding as judged by flow cytometry. Selected antibodies were capable of detecting PD-1 and PD-L1 on canine tissues by flow cytometry and Western blot. Anti-PD-L1 worked for immunocytochemistry and anti-PD-1 worked for immunohistochemistry on formalin-fixed paraffin embedded canine tissues, suggesting the usage of this antibody with archived tissues. Additionally, anti-PD-L1 (JC071) revealed significantly increased PD-L1 expression on canine monocytes after stimulation with peptidoglycan or lipopolysaccharide. Together, these antibodies display specificity for the natural canine ligand using a variety of potential diagnostic applications. Importantly, multiple PD-L1-specific antibodies amplified IFN-γ production in a canine peripheral blood mononuclear cells (PBMC) concanavlin A (Con A) stimulation assay, demonstrating functional activity.


Assuntos
Anticorpos Monoclonais/imunologia , Antígeno B7-H1/imunologia , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Cães , Interferon gama/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Peptidoglicano/farmacologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/metabolismo
10.
Anticancer Res ; 40(8): 4711-4717, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32727797

RESUMO

BACKGROUND: Continuous oral administration of lipopolysaccharide (LPS) enhances the phagocytic ability of macrophages, which is useful for preventing various diseases. Here, we attempted to create an in vitro model of continuous administration of LPS. MATERIALS AND METHODS: RAW264.7 cells were stimulated with LPS three times every 24 h (repeated stimulation), and phagocytic ability and inflammatory cytokine [interleukin-6 (IL6) and tumor necrosis factor-α (TNFα)] production were measured. RESULTS: The phagocytic ability was increased by a single stimulation with LPS and was maintained by repeated stimulation. IL6 production increased with a single stimulation with LPS; however, IL6 production by repeated stimulation with LPS was comparable to that of non-stimulation with LPS. On the other hand, the amount of TNFα was significantly increased by single and repeated stimulation with LPS. CONCLUSION: Repeated stimulation with LPS in RAW264.7 cells triggered a phenotype that was similar to that of macrophages after continuous oral administration of LPS. This suggests that this study model may reproduce the enhancement of macrophage phagocytosis, an effect afforded by continuous oral administration of LPS.


Assuntos
Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Animais , Linhagem Celular , Citocinas/metabolismo , Interleucina-6/metabolismo , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
11.
Clin Sci (Lond) ; 134(12): 1305-1318, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32478397

RESUMO

Podocyte injury and loss contribute to proteinuria, glomerulosclerosis and eventually kidney failure. Recent studies have demonstrated that the loss of Kruppel-like factor 15 (KLF15) in podocytes increases the susceptibility to injury; however, the mechanism underlying the protective effects on podocyte injury remains incompletely understood. Herein, we showed that KLF15 ameliorates podocyte injury through suppressing NFAT signaling and the salutary effects of the synthetic glucocorticoid dexamethasone in podocyte were partially mediated by the KLF15-NFATc1 axis. We found that KLF15 was significantly reduced in glomerular cells of proteinuric patients and in ADR-, LPS- or HG-treated podocyets in vitro. Overexpression of KLF15 attenuated podocyte apoptosis induced by ADR, LPS or HG and resulted in decreased expression of pro-apoptotic Bax and increased expression of anti-apoptotic Bcl-2. Conversely, the flow cytometry analysis and TUNEl assay demonstrated that loss of KLF15 accelerated podocyte apoptosis and we further found that 11R-VIVIT, a specific NFAT inhibitor, and NFATc1-siRNA rescued KLF15-deficient induced podocyte apoptosis. Meanwhile, Western blot and RT-qPCR showed that the expression of NFATc1 was up-regulated in KLF15 silenced podocytes and reduced in KLF15 overexpressed podocytes. Mechanistically, ChIP analysis showed that KLF15 bound to the NFATc1 promoter region -1984 to -1861base pairs upstream of the transcription start site and the binding amount was decreased after treatment with LPS. The dual-luciferase reporter assay indicated that NFATc1 was a direct target of KLF15. In addition, we found that in vitro treatment with dexamethasone induced a decrease of NFATc1 expression in podocytes and was abrogated by knockdown of KLF15. Hence, our results identify the critical role of the KLF15-NFATc1 axis in podocyte injury and loss, which may be involved in mediating the salutary effects of dexamethasone in podocytes.


Assuntos
Glucocorticoides/uso terapêutico , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição NFATC/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Dexametasona/farmacologia , Regulação para Baixo/efeitos dos fármacos , Doxorrubicina/farmacologia , Técnicas de Silenciamento de Genes , Inativação Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Glucose/toxicidade , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Modelos Biológicos , Transdução de Sinais
12.
Mol Immunol ; 124: 18-24, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32485435

RESUMO

Autophagy has been identified as an important immune regulatory mechanism. Recent studies have linked macrophage autophagy with innate immune responses against Mycobacterium tuberculosis (M. tuberculosis), which can survive within macrophages by blocking fusion of the phagosome with lysosomes. These findings suggest that autophagy is a regulatable cellular mechanism of M. tuberculosis defense in macrophages. Transcriptomic profiles in human blood in TB patients suggest that M. tuberculosis affects autophagy related pathways. In order to better understand the role of macrophage autophagy in enhancing protective immunity against M. tuberculosis, in this study, we investigate the effects of the autophagy activators rapamycin and LPS in macrophage autophagy and immunity against M. tuberculosis. We confirm that rapamycin and LPS induce autophagy in M. tuberculosis infected THP-1-derived macrophages or PMA primed THP-1 macrophages [THP-1(A)]. LPS restores M. tuberculosis-inhibited IL-12 synthesis and secretion in THP-1(A) cells via autophagy. Similarly, autophagy activators increase IL-12 synthesis and secretion in THP-1(A) cells. These studies demonstrate the importance of autophagy in M. tuberculosis elimination in macrophages and may lead to novel therapies for tuberculosis and other bacterial infections.


Assuntos
Autofagia/imunologia , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Autofagia/efeitos dos fármacos , Humanos , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia
13.
Sci Adv ; 6(23): eaaz5466, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32548259

RESUMO

Uncontrolled inflammatory processes are at the root of numerous pathologies. Most recently, studies on confirmed COVID-19 cases have suggested that mortality might be due to virally induced hyperinflammation. Uncontrolled pro-inflammatory states are often driven by continuous positive feedback loops between pro-inflammatory signaling and oxidative stress, which cannot be resolved in a targeted manner. Here, we report on the development of multidrug nanoparticles for the mitigation of uncontrolled inflammation. The nanoparticles are made by conjugating squalene, a natural lipid, to adenosine, an endogenous immunomodulator, and then encapsulating α-tocopherol, as antioxidant. This resulted in high drug loading, biocompatible, multidrug nanoparticles. By exploiting the endothelial dysfunction at sites of acute inflammation, these multidrug nanoparticles delivered the therapeutic agents in a targeted manner, conferring survival advantage to treated animals in models of endotoxemia. Selectively delivering adenosine and antioxidants together could serve as a novel therapeutic approach for safe treatment of acute paradoxal inflammation.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Endotoxemia/tratamento farmacológico , Nanopartículas/química , Esqualeno/química , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Adenosina/administração & dosagem , Adenosina/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Endotoxemia/induzido quimicamente , Feminino , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Esqualeno/administração & dosagem , Síndrome de Resposta Inflamatória Sistêmica/induzido quimicamente , Resultado do Tratamento , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/química
14.
DNA Cell Biol ; 39(7): 1274-1281, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32551893

RESUMO

Atherosclerosis is an immune inflammatory disease and a major cause of mortality and morbidity worldwide. It is generally considered that a number of potent proinflammatory cytokines have a great influence on its pathogenesis, including IL-1ß, IL-6, TNF-α, and NF-κB. A growing amount of empirical evidence indicates that the mechanism of cardiac dysfunction caused by lipopolysaccharide (LPS) is the activation of inflammation, but the exact mechanism in atherosclerosis is still unclear. Previous studies have shown that interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) participates in inflammation, but the effects and possible mechanism of action of IFIT1 on proinflammatory response remain largely unexplained. We found that LPS induced upregulation of IFIT1 expression in a time- and concentration-dependent manner in human umbilical vein endothelial cells (HUVECs). Overexpression of IFIT1 significantly upregulated LPS-induced expression of IL-1ß, IL-6, TNF-α, and NF-κB in HUVECs. IFIT1-siRNA treatment dramatically decreased LPS-induced expression of IL-1ß, IL-6, TNF-α, and NF-κB in HUVECs. The above results show that LPS induces expression of IL-1ß, IL-6, TNF-α, and NF-κB through upregulating IFIT1 expression in HUVECs, and suggested that IFIT1 could act as potential therapeutic target to ameliorate atherosclerosis-related diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas de Ligação a RNA/genética , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo
15.
Int J Nanomedicine ; 15: 3649-3667, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547020

RESUMO

Introduction: The polyphenolic spice and food coloring ingredient curcumin has beneficial effects in a broad variety of inflammatory diseases. Amongst them, curcumin has been shown to attenuate microglia reaction and prevent from glial scar formation in spinal cord and brain injuries. Methods: We developed a protocol for the efficient encapsulation of curcumin as a model for anti-inflammatory drugs yielding long-term stable, non-toxic liposomes with favorable physicochemical properties. Subsequently, we evaluate the effects of liposomal curcumin in experimental models for neuroinflammation and reactive astrogliosis. Results: We could show that liposomal curcumin can efficiently reduce the reactivity of human microglia and astrocytes and preserve tissue integrity of murine organotypic cortex slices. Discussion and Perspective: In perspective, we want to administer this curcumin formulation in brain implant coatings to prevent neuroinflammation and glial scar formation as foreign body responses of the brain towards implanted materials.


Assuntos
Encéfalo/patologia , Curcumina/uso terapêutico , Gliose/tratamento farmacológico , Inflamação/tratamento farmacológico , Neuroglia/patologia , Animais , Anti-Inflamatórios/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/ultraestrutura , Encéfalo/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Humanos , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Lipossomos , Camundongos , Microglia/efeitos dos fármacos , Microglia/ultraestrutura , Neuroglia/efeitos dos fármacos
16.
PLoS Biol ; 18(6): e3000722, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32569301

RESUMO

Inflammation and infection can trigger local tissue Na+ accumulation. This Na+-rich environment boosts proinflammatory activation of monocyte/macrophage-like cells (MΦs) and their antimicrobial activity. Enhanced Na+-driven MΦ function requires the osmoprotective transcription factor nuclear factor of activated T cells 5 (NFAT5), which augments nitric oxide (NO) production and contributes to increased autophagy. However, the mechanism of Na+ sensing in MΦs remained unclear. High extracellular Na+ levels (high salt [HS]) trigger a substantial Na+ influx and Ca2+ loss. Here, we show that the Na+/Ca2+ exchanger 1 (NCX1, also known as solute carrier family 8 member A1 [SLC8A1]) plays a critical role in HS-triggered Na+ influx, concomitant Ca2+ efflux, and subsequent augmented NFAT5 accumulation. Moreover, interfering with NCX1 activity impairs HS-boosted inflammatory signaling, infection-triggered autolysosome formation, and subsequent antibacterial activity. Taken together, this demonstrates that NCX1 is able to sense Na+ and is required for amplifying inflammatory and antimicrobial MΦ responses upon HS exposure. Manipulating NCX1 offers a new strategy to regulate MΦ function.


Assuntos
Macrófagos/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Sódio/metabolismo , Processamento Alternativo/genética , Animais , Cálcio/metabolismo , Espaço Extracelular/metabolismo , Inativação Gênica/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Íons , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/biossíntese , Células RAW 264.7 , Cloreto de Sódio/farmacologia
17.
J Cancer Res Clin Oncol ; 146(9): 2219-2229, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32507974

RESUMO

PURPOSE: Pancreatic cancer is a lethal form of cancer that can be triggered by prolonged or acute inflammation of the pancreas. Inflammation have been shown to be regulated by a group of key protein molecules known as the inflammasomes. The NLRP3 inflammasome is the most studied inflammasome and have been strongly implicated to regulate cancer cell proliferation. Therefore, this study aimed to examine the regulation of NLRP3 inflammasome under LPS-induced inflammation and its role in modulating cell proliferation in a panel of pancreatic cancer cells. METHODS: The effects of LPS-induced NLRP3 activation in the presence or absence of MCC950, NLRP3-specific inhibitor, was tested on a panel of three pancreatic cancer cell lines (SW1990, PANC1 and Panc10.05). Western blotting, cell viability kits and ELISA kits were used to examine the effects of LPS-induced NLRP3 activation and inhibition by MCC950 on NLRP3 expression, cell viability, caspase-1 activity and cytokine IL-1ß, respectively. RESULTS: LPS-induced inflammation in the presence of ATP activates NLRP3 that subsequently increases pancreatic cancer cell proliferation by increasing caspase-1 activity leading to overall production of IL-1ß. The inhibition of the NLRP3 inflammasome activation via the specific NLRP3 antagonist MCC950 was able to reduce the cell viability of pancreatic cancer cells. However, the efficacy of MCC950 varies between cell types which is most probably due to the difference in ASC expressions which have a different role in inflammasome activation. CONCLUSION: There is a dynamic interaction between inflammasome that regulates inflammasome-mediated inflammation in pancreatic adenocarcinoma cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Inflamassomos/efeitos dos fármacos , Inflamação/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Sulfonas/farmacologia , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/metabolismo
18.
Life Sci ; 256: 117894, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502544

RESUMO

AIMS: Pathological alterations in the brain can cause microglial activation (MA). Thus, inhibiting MA could provide a new approach for treating neurodegenerative disorders. MAIN METHODS: To investigate the effect of C16 peptide and angiopoietin-1 (Ang1) on inflammation following MA, we stimulated microglial BV-2 cells with lipopolysaccharide (LPS) and used dexmedetomidine (DEX) as a positive control. Specific inhibitors of Tie2, αvß3 and α5ß1 integrins, and PI3K/Akt were applied to investigate the neuron-protective and anti-inflammatory effects and signaling pathway of C16 + Ang1 treatment in the LPS-induced BV-2 cells. KEY FINDINGS: Our results showed that C16 + Ang1 treatment reduced the microglia M1 phenotype but promoted the microglia M2 phenotype. In addition, C16 + Ang1 treatment suppressed leukocyte migration across human pulmonary microvascular endothelial cells, reduced the levels of pro-inflammatory factors [inducible nitric oxide synthase (iNOS), interleukin (IL)-1ß, tumor necrosis factor (TNF-α)], and cellular apoptosis factors (caspase-3 and p53), and decreased lactate dehydrogenase (LDH) release, but promoted anti-inflammatory cytokine (IL-10) expression and cell proliferation in the LPS-activated BV-2 cells. The signaling pathways underlying the neuron-protective and anti-inflammatory effects of C16 + Ang1 may be mediated by Tie2-PI3K/Akt, Tie2-integrin and integrin-PI3K/Akt. SIGNIFICANCE: The neuron-protective and anti-inflammatory effects of C16 + Ang1 treatment included M1 to M2 microglia phenotype switching, blocking leukocyte transmigration, decreasing apoptotic and inflammatory factors, and promoting cellular viability.


Assuntos
Angiopoietina-1/farmacologia , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Microglia/patologia , Fármacos Neuroprotetores/farmacologia , Peptídeos/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Integrina alfa5beta1/metabolismo , Integrina alfaVbeta3/metabolismo , Pulmão/irrigação sanguínea , Camundongos , Microglia/efeitos dos fármacos , Microvasos/patologia , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor TIE-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células THP-1
19.
PLoS One ; 15(6): e0234038, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492075

RESUMO

Extracellular adenosine triphosphate (eATP) released by damaged cells, and its purinergic receptors, comprise a crucial signaling network after injury. Purinergic receptor P2X7 (P2RX7), a major driver of NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and IL-1ß processing, has been shown to play a role in liver injury in murine diet- and chemically-induced liver injury models. It is unclear, however, whether P2RX7 plays a role in non-alcoholic steatohepatitis (NASH) and which cell type is the main target of P2RX7 pharmacological inhibition. Here, we report that P2RX7 is expressed by infiltrating monocytes and resident Kupffer cells in livers from NASH-affected individuals. Using primary isolated human cells, we demonstrate that P2RX7 expression in CD14+ monocytes and Kupffer cells primarily mediates IL-1ß release. In addition, we show that pharmacological inhibition of P2RX7 in monocytes and Kupffer cells, blocks IL-1ß release, reducing hepatocyte caspase 3/7 activity, IL-1ß-mediated CCL2 and CCL5 chemokine gene expression and secretion, and hepatic stellate cell (HSC) procollagen secretion. Consequently, in a chemically-induced nonhuman primate model of liver fibrosis, treatment with a P2RX7 inhibitor improved histological characteristics of NASH, protecting from liver inflammation and fibrosis. Taken together, these findings underscore the critical role of P2RX7 in the pathogenesis of NASH and implicate P2RX7 as a promising therapeutic target for the management of this disease.


Assuntos
Inflamação/prevenção & controle , Cirrose Hepática/tratamento farmacológico , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Receptores Purinérgicos P2X7/metabolismo , Animais , Caspase 3/metabolismo , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inflamação/patologia , Interleucina-1beta/metabolismo , Macrófagos do Fígado/citologia , Macrófagos do Fígado/efeitos dos fármacos , Macrófagos do Fígado/metabolismo , Lipopolissacarídeos/farmacologia , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Macaca fascicularis , Masculino , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Pró-Colágeno/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/química , Receptores Purinérgicos P2X7/genética
20.
Yonsei Med J ; 61(6): 533-541, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32469177

RESUMO

PURPOSE: Ethanol elicits several inflammatory responses and affects the innate immune response. The aim of this study was to identify the mechanism by which ethanol affects uric acid-induced NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation by regulation of aryl hydrocarbon receptor (AhR) and thioredoxin-interacting protein (TXNIP). MATERIALS AND METHODS: Human myeloid leukemia cells (U937 cells) were used to assess the role of ethanol in NLRP3 inflammasome activation induced by monosodium urate (MSU) crystals. Expression of target molecules, such as NLRP3 inflammasome components, AhR, and TXNIP, were measured using quantitative real-time PCR and Western blot analyses. The effect of ethanol-induced TXNIP on the NLRP3 inflammasome was assessed in human macrophages transfected with TXNIP siRNA. RESULTS: U937 cells treated with 100 mM ethanol for 24 h induced NLRP3 and interleukin (IL)-1ß expression. Ethanol increased reactive oxygen species generation in a time- and dose-dependent manner. AhR mRNA expression was downregulated in U937 cells treated with 100 mM ethanol, whereas CYP1A1 mRNA expression increased. Treatment with ethanol increased NLRP3 and IL-1ß mRNA and protein expression in U937 cells exposed to 1.0 mg/mL of MSU crystals for 24 h. TXNIP expression in U937 cells incubated with both 100 mM ethanol and 1.0 mg/mL of MSU crystals was significantly higher than in cells incubated with MSU crystals alone. Treatment with 100mM ethanol for 24 h downregulated NLRP3 and IL-1ß expression in MSU crystal-activated U937 cells transfected with TXNIP siRNA, compared to those with scramble siRNA. CONCLUSION: Ethanol stimulates uric acid-induced NLRP3 inflammasome activation through regression of AhR and upregulation of TXNIP.


Assuntos
Proteínas de Transporte/metabolismo , Etanol/toxicidade , Inflamassomos/metabolismo , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Ácido Úrico/toxicidade , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Espécies Reativas de Oxigênio/metabolismo , Células U937
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