Spred2-deficiency enhances the proliferation of lung epithelial cells and alleviates pulmonary fibrosis induced by bleomycin.

The mitogen-activated protein kinase (MAPK) pathways are involved in many cellular processes, including the development of fibrosis. Here, we examined the role of Sprouty-related EVH-1-domain-containing protein (Spred) 2, a negative regulator of the MAPK-ERK pathway, in the development of bleomycin (BLM)-induced pulmonary fibrosis (PF). Compared to WT mice, Spred2-/- mice developed milder PF with increased proliferation of bronchial epithelial cells. Spred2-/- lung epithelial cells or MLE-12 cells treated with spred2 siRNA proliferated faster than control cells in vitro. Spred2-/- and WT macrophages produced similar levels of TNFα and MCP-1 in response to BLM or lipopolysaccharide and myeloid cell-specific deletion of Spred2 in mice had no effect. Spred2-/- fibroblasts proliferated faster and produced similar levels of MCP-1 compared to WT fibroblasts. Spred2 mRNA was almost exclusively detected in bronchial epithelial cells of naïve WT mice and it accumulated in approximately 50% of cells with a characteristic of Clara cells, 14 days after BLM treatment. These results suggest that Spred2 is involved in the regulation of tissue repair after BLM-induced lung injury and increased proliferation of lung bronchial cells in Spred2-/- mice may contribute to faster tissue repair. Thus, Spred2 may present a new therapeutic target for the treatment of PF.

Citation

Akina Kawara, Ryo Mizuta, Masayoshi Fujisawa, Toshihiro Ito, Chunning Li, Kaoru Nakamura, Cuiming Sun, Masaki Kuwabara, Masahiro Kitabatake, Teizo Yoshimura, Akihiro Matsukawa. Spred2-deficiency enhances the proliferation of lung epithelial cells and alleviates pulmonary fibrosis induced by bleomycin. Scientific reports. 2020 Oct 05;10(1):16490

Mesh Tags

Substances

PMID: 33020583

search → result