Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 569(7755): 236-240, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043745

RESUMO

The perpetuation of inflammation is an important pathophysiological contributor to the global medical burden. Chronic inflammation is promoted by non-programmed cell death1,2; however, how inflammation is instigated, its cellular and molecular mediators, and its therapeutic value are poorly defined. Here we use mouse models of atherosclerosis-a major underlying cause of mortality worldwide-to demonstrate that extracellular histone H4-mediated membrane lysis of smooth muscle cells (SMCs) triggers arterial tissue damage and inflammation. We show that activated lesional SMCs attract neutrophils, triggering the ejection of neutrophil extracellular traps that contain nuclear proteins. Among them, histone H4 binds to and lyses SMCs, leading to the destabilization of plaques; conversely, the neutralization of histone H4 prevents cell death of SMCs and stabilizes atherosclerotic lesions. Our data identify a form of cell death found at the core of chronic vascular disease that is instigated by leukocytes and can be targeted therapeutically.


Assuntos
Aterosclerose/patologia , Morte Celular , Membrana Celular/metabolismo , Histonas/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Porosidade , Animais , Artérias/patologia , Membrana Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Histonas/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/patologia , Neutrófilos/citologia , Ligação Proteica/efeitos dos fármacos
2.
Circulation ; 143(3): 254-266, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33167684

RESUMO

BACKGROUND: Acute infection is a well-established risk factor of cardiovascular inflammation increasing the risk for a cardiovascular complication within the first weeks after infection. However, the nature of the processes underlying such aggravation remains unclear. Lipopolysaccharide derived from Gram-negative bacteria is a potent activator of circulating immune cells including neutrophils, which foster inflammation through discharge of neutrophil extracellular traps (NETs). Here, we use a model of endotoxinemia to link acute infection and subsequent neutrophil activation with acceleration of vascular inflammation Methods: Acute infection was mimicked by injection of a single dose of lipopolysaccharide into hypercholesterolemic mice. Atherosclerosis burden was studied by histomorphometric analysis of the aortic root. Arterial myeloid cell adhesion was quantified by intravital microscopy. RESULTS: Lipopolysaccharide treatment rapidly enhanced atherosclerotic lesion size by expansion of the lesional myeloid cell accumulation. Lipopolysaccharide treatment led to the deposition of NETs along the arterial lumen, and inhibition of NET release annulled lesion expansion during endotoxinemia, thus suggesting that NETs regulate myeloid cell recruitment. To study the mechanism of monocyte adhesion to NETs, we used in vitro adhesion assays and biophysical approaches. In these experiments, NET-resident histone H2a attracted monocytes in a receptor-independent, surface charge-dependent fashion. Therapeutic neutralization of histone H2a by antibodies or by in silico designed cyclic peptides enables us to reduce luminal monocyte adhesion and lesion expansion during endotoxinemia. CONCLUSIONS: Our study shows that NET-associated histone H2a mediates charge-dependent monocyte adhesion to NETs and accelerates atherosclerosis during endotoxinemia.


Assuntos
Aterosclerose/metabolismo , Adesão Celular/fisiologia , Endotoxemia/metabolismo , Monócitos/metabolismo , Eletricidade Estática , Animais , Aterosclerose/induzido quimicamente , Aterosclerose/patologia , Adesão Celular/efeitos dos fármacos , Endotoxemia/induzido quimicamente , Endotoxemia/patologia , Armadilhas Extracelulares/metabolismo , Humanos , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/efeitos dos fármacos , Monócitos/patologia
4.
Cells ; 10(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34440753

RESUMO

Neutrophil extracellular traps (NETs) are networks of extracellular genetic material decorated with proteins of nuclear, granular and cytosolic origin that activated neutrophils expel under pathogenic inflammatory conditions. NETs are part of the host's innate immune defense system against invading pathogens. Interestingly, these extracellular structures can also be released in response to sterile inflammatory stimuli (e.g., shear stress, lipidic molecules, pro-thrombotic factors, aggregated platelets, or pro-inflammatory cytokines), as in atherosclerosis disease. Indeed, NETs have been identified in the intimal surface of diseased arteries under cardiovascular disease conditions, where they sustain inflammation via NET-mediated cell-adhesion mechanisms and promote cellular dysfunction and tissue damage via NET-associated cytotoxicity. This review will focus on (1) the active role of neutrophils and NETs as underestimated players of the inflammatory process during atherogenesis and lesion progression; (2) how these extracellular structures communicate with the main cell types present in the atherosclerotic lesion in the arterial wall; and (3) how these neutrophil effector functions interplay with lifestyle-derived risk factors such as an unbalanced diet, physical inactivity, smoking or lack of sleep quality, which represent major elements in the development of cardiovascular disease.


Assuntos
Aterosclerose/imunologia , Armadilhas Extracelulares/imunologia , Inflamação/imunologia , Estilo de Vida , Ativação de Neutrófilo/imunologia , Neutrófilos/imunologia , Artérias/imunologia , Artérias/metabolismo , Artérias/patologia , Aterosclerose/metabolismo , Armadilhas Extracelulares/metabolismo , Humanos , Inflamação/metabolismo , Modelos Imunológicos , Neutrófilos/metabolismo , Obesidade/imunologia , Obesidade/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA