Dataset Information

1,25-Dihydroxyvitamin D Modulates Antibacterial and Inflammatory Response in Human Cigarette Smoke-Exposed Macrophages.

ABSTRACT: Cigarette smoking is associated with increased inflammation and defective antibacterial responses in the airways. Interestingly, vitamin D has been shown to suppress inflammation and to improve antibacterial defense. However, it is currently unknown whether vitamin D may modulate inflammation and antibacterial defects in human cigarette smoke (CS)-exposed airways. To explore these unresolved issues, alveolar macrophages obtained from non-smoking and smoking subjects as well as human cigarette smoke extract (CSE)-treated THP-1 macrophages were stimulated with 1,25-dihydroxyvitamin D (1,25(OH)2D) to address inflammatory and antibacterial responses. Although basal levels of inflammatory cytokines and chemokines did not differ between non-smoking and smoking subjects, 1,25(OH)2D did reduce levels of IL-6, TNF-? and MCP-1 in alveolar macrophages in response to LPS/IFN-?, although not statistically significant for TNF-? and IL-6 in smokers. CSE did not significantly alter vitamin D metabolism (expression levels of CYP24A1 or CYP27B1) in THP-1 macrophages. Furthermore, stimulation with 1,25(OH)2D reduced mRNA expression levels and/or protein levels of IL-8, TNF-? and MCP-1 in CSE-treated THP-1 macrophages. 1,25(OH)2D did not improve defects in phagocytosis of E. coli bacteria or the oxidative burst response in CSE-treated THP-1 macrophages or alveolar macrophages from smokers. However, 1,25(OH)2D significantly enhanced mRNA expression and/or protein levels of the antimicrobial peptide cathelicidin in alveolar macrophages and THP-1 macrophages, independently of CS exposure. In conclusion, our results provide the first evidence that vitamin D could be a new strategy for attenuating airway inflammation and improving antibacterial defense in CS-exposed airways.

SUBMITTER: Heulens N

PROVIDER: S-EPMC4981391 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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1,25-Dihydroxyvitamin D Modulates Antibacterial and Inflammatory Response in Human Cigarette Smoke-Exposed Macrophages.

Heulens Nele N Korf Hannelie H Mathyssen Carolien C Everaerts Stephanie S De Smidt Elien E Dooms Christophe C Yserbyt Jonas J Gysemans Conny C Gayan-Ramirez Ghislaine G Mathieu Chantal C Janssens Wim W

PloS one 20160811 8

Cigarette smoking is associated with increased inflammation and defective antibacterial responses in the airways. Interestingly, vitamin D has been shown to suppress inflammation and to improve antibacterial defense. However, it is currently unknown whether vitamin D may modulate inflammation and antibacterial defects in human cigarette smoke (CS)-exposed airways. To explore these unresolved issues, alveolar macrophages obtained from non-smoking and smoking subjects as well as human cigarette sm ...[more]

PMID: 27513734

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Dataset Information

1,25-Dihydroxyvitamin D Modulates Antibacterial and Inflammatory Response in Human Cigarette Smoke-Exposed Macrophages.

Publications

1,25-Dihydroxyvitamin D Modulates Antibacterial and Inflammatory Response in Human Cigarette Smoke-Exposed Macrophages.

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