| First Author | Cai Y | Year | 2015 |
| Journal | PLoS One | Volume | 10 |
| Issue | 11 | Pages | e0142497 |
| PubMed ID | 26559674 | Mgi Jnum | J:244725 |
| Mgi Id | MGI:5913504 | Doi | 10.1371/journal.pone.0142497 |
| Citation | Cai Y, et al. (2015) Secretoglobin 3A2 Exhibits Anti-Fibrotic Activity in Bleomycin-Induced Pulmonary Fibrosis Model Mice. PLoS One 10(11):e0142497 |
| abstractText | OBJECTIVE: Secretoglobin (SCGB) 3A2 is a novel lung-enriched cytokine, previously shown to exhibit anti-inflammatory, growth factor, and anti-fibrotic activities. The latter activity was demonstrated using exogenously-administered recombinant SCGB3A2 in the bleomycin (BLM)-induced pulmonary fibrosis model. Whether SCGB3A2 exhibits anti-fibrotic activity in vivo is not known. METHODS: Mice null for the Scgb3a2 gene were subjected to the BLM-induced pulmonary fibrosis model, and the severity of pulmonary fibrosis determined using histological and biochemical methods. RESULTS: BLM treatment caused weight loss of both Scgb3a2-null and wild-type mice, however, the loss was far more pronounced in BLM-treated Scgb3a2-null than wild-type mice, and the weight of day 21 of BLM-treated Scgb3a2-null mice was about half of that of BLM-treated wild-type mice. Hematoxylin & Eosin, Masson Trichrome, and Sirius Red staining of lung sections, Ashcroft fibrosis scores, hydroxyproline contents, and the levels of mRNAs encoding various collagens demonstrated that BLM-treated Scgb3a2-null mouse lungs had more severe fibrosis than those of wild-type mouse lungs. Total and differential inflammatory cell numbers in bronchoalveolar lavage fluids, and levels of lung mRNAs including those encoding Th2 cytokines such as IL-4 and profibrotic cytokines such as TGFbeta were higher in BLM-treated Scgb3a2-null mouse lungs as compared to those of wild-type mouse lungs. In contrast, mRNAs encoding surfactant proteins A, B, C, and D, and SCGB1A1 did not differ between BLM-treated Scgb3a2-null and wild-type mouse lungs. CONCLUSION: The role of SCGB3A2 in fibrosis was revisited using Scgb3a2-null mice and littermate controls in the BLM-induced pulmonary fibrosis model. The pulmonary fibrosis in the Scgb3a2-null mice was more severe than the wild-type controls, thus establishing that SCGB3A2 has anti-fibrotic activity in vivo. Importantly, surfactant proteins and SCGB1A1 appear not to be involved in the susceptibility of Scgb3a2-null mice to BLM-induced pulmonary fibrosis. |
