Vitamin D supplementation reduces airway hyperresponsiveness and allergic airway inflammation in a murine model
Article first published online: 28 MAY 2013
© 2013 John Wiley & Sons Ltd
Clinical & Experimental Allergy
Volume 43, Issue 6, pages 672–683, June 2013
How to Cite
Clinical & Experimental Allergy, 2013 43.672–683., , ,
- Issue published online: 28 MAY 2013
- Article first published online: 28 MAY 2013
- Accepted manuscript online: 23 FEB 2013 04:00AM EST
- Manuscript Accepted: 4 FEB 2013
- Manuscript Revised: 29 JAN 2013
- Manuscript Received: 17 JUL 2012
- National Institutes of Health. Grant Numbers: R01AI75315, R01HL116042
- allergic airway in?ammation;
- T-regulatory cells;
- vitamin D;
- vitamin D receptor
Asthma is a chronic disease associated with airway hyperresponsiveness (AHR), airway obstruction and airway remodelling. NF-κB is a transcriptional factor that regulates and co-ordinates the expression of various inflammatory genes. The NF-κB subunits, p50 and Rel-A, are translocated to the nucleus by importin α3 and importin α4. There is growing evidence that vitamin D is a potent immunomodulator. However, the evidence for beneficial or adverse effects of vitamin D in asthma is still unclear.
In this study, we examined the effect of vitamin D status on AHR, airway inflammation and cytokines in the bronchoalveolar lavage fluid (BALF) in a murine model of allergic asthma.
Female BALB/c mice were fed with special vitamin D-deficient or vitamin D-sufficient (2000 IU/kg) or vitamin D-supplemented (10 000 IU/kg) diet for 13 weeks. Mice were sensitized and challenged with ovalbumin (OVA). The effect of vitamin D on lung histology, AHR, T regulatory cells (Tregs) and BALF cytokines was examined. The expression of importin-α3 and Rel-A in the lung of OVA-sensitized mice was analysed using immunofluorescence.
Vitamin D deficiency was associated with higher AHR in OVA-sensitized and challenged mice than those in vitamin D-sufficient mice. This was accompanied with marked signs of airway remodelling, high BALF eosinophilia, increased BALF pro-inflammatory cytokines, reduced BALF IL-10 levels, reduced blood Tregs, increased expression of importin-α3 and Rel-A in the lung tissue. Vitamin D supplementation attenuated the pro-inflammatory effects, but did not completely reverse the features of allergic airway inflammation.
Conclusion and Clinical Relevance
Vitamin D could be beneficial as an adjunct therapy in the treatment of allergic asthma.