Abstract
Aims:
Silicosis is a lung disease caused by inhalation of silica particles. Both silica-induced oxidative stress and aberrant activation of the Wnt/β-catenin signaling pathway are potential targets in the treatment of pulmonary fibrosis. Dickkopf-1 (Dkk1), an inhibitor of the Wnt/β-catenin signaling pathway, plays regulatory roles in cell fate determination and immune responses. Our previous study demonstrated that adenoviral vector-mediated Dkk1 gene transfer alleviated the silica-induced mouse silicosis. However, the mechanism of therapeutic action of Dkk1 in silicosis is yet completely understood; together with the drawbacks of adenoviral vectors in gene therapy, we investigated the therapeutic effect and mechanisms of Dkk1 by employing an adeno-associated virus (AAV) vector in a silicosis mouse model.
Results:
The AAV vector could efficiently transduce the Dkk1 gene in silicotic lung during both the early and the late phases of disease, resulting in an alleviation of silicotic lesions, improvement of pulmonary compliance, and radiological findings. Mechanistic studies further demonstrated that the transduction of Dkk1 inhibited the silica-activated Wnt/β-catenin signaling and reduced the silica-induced reactive oxygen species-producing enzyme NADPH oxidase 4, oxidative stress regulator nuclear factor erythroid 2-related factor 2, and signaling molecules binding immunoglobulin protein and C/EBP homologous protein. In addition, shRNA-mediated downregulation of Dkk1 exacerbated the progression of silicosis in mice, whereas the treatment of ROS scavenger
Innovation and Conclusion:
This study provides an insight into the mechanism by which Dkk1 inhibits the silica-induced Wnt signaling and oxidative stress to mitigate the pathogenesis of lung silicosis and evidence of the potential of AAV-mediated Dkk1 gene transfer as an alternative approach in silicosis treatment. Antioxid. Redox Signal. 42, 529–546.
Get full access to this article
View all access options for this article.
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
