Curcumin reduces lung inflammation via Wnt/β-catenin signaling in mouse model of asthma

ABSTRACT

Objectives: Asthma is a chronic inflammatory, heterogeneous airway disease affecting millions of people around the world. Curcumin has been found to have anti-inflammatory and antifibrosis effects. Researchers reported that curcumin regulated Wnt/β-catenin signaling in lots of cells. However, whether curcumin regulates the levels of Wnt/β-Catenin signaling in lung tissues and DCs (dendritic cells) remains unclear. In this study, we assessed the effects of curcumin on DCs and asthma. Methods: C57BL/6 mice immunized with OVA (ovalbumin) were challenged thrice with an aerosol of OVA every second day for 8 days. Dexamethasone or curcumin was administered intraperitoneally to OVA-immunized C57BL/6 mice on day 24 once a day for 9 days. Mice were analyzed for effects of curcumin on asthma, inflammatory cell infiltration and cytokine levels in lung tissue. DCs were isolated from mouse bone morrow. The surface markers CD40, CD86 and CD11c of DCs was detected by FACS (fluorescence activated cell sorting) and the function of DCs was detected by mixed lymphocyte reaction. The expression of GSK-3β and β-catenin was detected by Western Blot. Results: Results showed that OVA increased the number of inflammatory factors in BALF (bronchoalveolar lavage fluid), elevated lung inflammation scores in mice. Curcumin dose-dependently reversed the alterations induced by OVA in the asthmatic mice. Curcumin activated Wnt/β-catenin signaling pathway in DCs and asthmatic mouse lungs. Conclusions: Curcumin could influence the morphology and function of DCs, ease asthma symptom and inflammatory reaction through the activation of Wnt/β-catenin signaling. These results provide new evidence new evidence for application of curcumin on asthma.

KEYWORDS:

• Asthma
• Curcumin
• Wnt/β-Catenin
• GSK-3β
• dendritic cells (DCs)

Acknowledgments

Authors Xia Yang, Jian-Ning Lv, Hui Li, and Bo Jiao contributed equally to this study.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Funding

This work was supported by the grant from a social development research project in Department of Science and Technology, Shaanxi Province, China (The role of curcumin in airway inflammation of asthma mouse and Wnt/β-Catenin signaling pathway of DCs,Grant No:2014K11-02-03-08; The role of Humulus scandens pollen pTSX pretreatment in airway complaisance inflammation of asthma, Grant No:2011K12-01-03). We are indebted to the members of our laboratories at the Department of Respiratory Medicine, the Second Affiliated Hospital of Xi'an Jiaotong University and Department of Aerospace Physiology, Fourth Military Medical University.