Abstract |
Phagocytes not only coordinate acute inflammation and host defense at mucosal sites, but also contribute to tissue damage. Respiratory infection causes a globally significant disease burden and frequently progresses to acute respiratory distress syndrome, a devastating inflammatory condition characterized by neutrophil recruitment and accumulation of protein-rich edema fluid causing impaired lung function. We hypothesized that targeting the intracellular protein myeloid cell leukemia 1 (Mcl-1) by a cyclin-dependent kinase inhibitor ( AT7519) or a flavone ( wogonin) would accelerate neutrophil apoptosis and resolution of established inflammation, but without detriment to bacterial clearance. Mcl-1 loss induced human neutrophil apoptosis, but did not induce macrophage apoptosis nor impair phagocytosis of apoptotic neutrophils. Neutrophil-dominant inflammation was modelled in mice by either endotoxin or bacteria (Escherichia coli). Downregulating inflammatory cell Mcl-1 had anti-inflammatory, pro-resolution effects, shortening the resolution interval (Ri) from 19 to 7 h and improved organ dysfunction with enhanced alveolar-capillary barrier integrity. Conversely, attenuating drug-induced Mcl-1 downregulation inhibited neutrophil apoptosis and delayed resolution of endotoxin-mediated lung inflammation. Importantly, manipulating lung inflammatory cell Mcl-1 also accelerated resolution of bacterial infection (Ri; 50 to 16 h) concurrent with enhanced bacterial clearance. Therefore, manipulating inflammatory cell Mcl-1 accelerates inflammation resolution without detriment to host defense against bacteria, and represents a target for treating infection-associated inflammation.
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Authors | C D Lucas, D A Dorward, M A Tait, S Fox, J A Marwick, K C Allen, C T Robb, N Hirani, C Haslett, R Duffin, A G Rossi |
Journal | Mucosal immunology
(Mucosal Immunol)
Vol. 7
Issue 4
Pg. 857-68
(Jul 2014)
ISSN: 1935-3456 [Electronic] United States |
PMID | 24280938
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- 4-(2,6-dichlorobenzoylamino)-1H-pyrazole-3-carboxylic acid piperidin-4-ylamide
- Myeloid Cell Leukemia Sequence 1 Protein
- Piperidines
- Pyrazoles
- Caspases
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Topics |
- Animals
- Apoptosis
(drug effects, immunology)
- Caspases
(metabolism)
- Disease Models, Animal
- Female
- Gene Expression Regulation
(drug effects)
- Humans
- Lung
(immunology, metabolism, microbiology, pathology)
- Macrophages
(drug effects, immunology, metabolism)
- Mice
- Myeloid Cell Leukemia Sequence 1 Protein
(genetics, metabolism)
- Neutrophil Infiltration
(immunology)
- Neutrophils
(drug effects, immunology, metabolism)
- Piperidines
(pharmacology)
- Pneumonia
(genetics, immunology, metabolism, microbiology, pathology)
- Pyrazoles
(pharmacology)
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