Identification of tyrosine brominated extracellular matrix proteins in normal and fibrotic lung tissues

• Published in: Redox biology Vol. 71; p. 103102
• Main Authors: Cruz, Litiele Cezar, Habibovic, Aida, Dempsey, Bianca, Massafera, Mariana P., Janssen-Heininger, Yvonne M.W., Lin, Miao-chong Joy, Hoffman, Evan T., Weiss, Daniel J., Huang, Steven K., van der Vliet, Albert, Meotti, Flavia C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2024; Elsevier
• Subjects: Animals; Bromates; Bromides - adverse effects; Bromides - metabolism; Bromotyrosine; Collagen; Collagen Type IV - metabolism; Extracellular Matrix - metabolism; Extracellular Matrix Proteins - genetics; Extracellular Matrix Proteins - metabolism; Humans; Hypobromous acid; Laminin; Laminin - genetics; Laminin - metabolism; Lung - metabolism; Mice; Peroxidasin; Pulmonary fibrosis; Pulmonary Fibrosis - chemically induced; Pulmonary Fibrosis - genetics; Pulmonary Fibrosis - metabolism; Research Paper; Tubulointerstitial nephritis antigen-like 1; Tyrosine - metabolism; Bromotyrosine; Laminin; Pulmonary fibrosis; Collagen; Tubulointerstitial nephritis antigen-like 1; Peroxidasin; Hypobromous acid
• ISSN: 2213-2317; 2213-2317
• DOI: 10.1016/j.redox.2024.103102

Peroxidasin (PXDN) is a secreted heme peroxidase that catalyzes the oxidative crosslinking of collagen IV within the extracellular matrix (ECM) via intermediate hypobromous acid (HOBr) synthesis from hydrogen peroxide and bromide, but recent findings have also suggested alternative ECM protein modifications by PXDN, including incorporation of bromide into tyrosine residues. In this work, we sought to identify the major target proteins for tyrosine bromination by HOBr or by PXDN-mediated oxidation in ECM from mouse teratocarcinoma PFHR9 cells. We detected 61 bromotyrosine (BrY)-containing peptides representing 23 proteins in HOBr-modified ECM from PFHR9 cells, among which laminins displayed the most prominent bromotyrosine incorporation. Moreover, we also found that laminin α1, laminin β1, and tubulointerstitial nephritis antigen-like (TINAGL1) contained BrY in untreated PFHR9 cells, which depended on PXDN. We extended these analyses to lung tissues from both healthy mice and mice with experimental lung fibrosis, and in lung tissues obtained from human subjects. Analysis of ECM-enriched mouse lung tissue extracts showed that 83 ECM proteins were elevated in bleomycin-induced fibrosis, which included various collagens and laminins, and PXDN. Similarly, mRNA and protein expression of PXDN and laminin α/β1 were enhanced in fibrotic mouse lung tissues, and also in mouse bone-marrow-derived macrophages or human fibroblasts stimulated with transforming growth factor β1, a profibrotic growth factor. We identified 11 BrY-containing ECM proteins, including collagen IV α2, collagen VI α1, TINAGL1, and various laminins, in both healthy and mouse fibrotic lung tissues, although the relative extent of tyrosine bromination of laminins was not significantly increased during fibrosis. Finally, we also identified 7 BrY-containing ECM proteins in human lung tissues, again including collagen IV α2, collagen VI α1, and TINAGL1. Altogether, this work demonstrates the presence of several bromotyrosine-modified ECM proteins, likely involving PXDN, even in normal lung tissues, suggesting a potential biological function for these modifications. [Display omitted] •Laminin is the primary tyrosine-brominated protein in the ECM from PHFR9 cells and mouse lungs;•Peroxidasin brominates laminin and tubulointerstitial nephritis antigen-like in ECM from PHFR9 cells;•Peroxidasin, laminins, collagens, and various other ECM proteins are upregulated in the lungs of mice with experimental fibrosis;•Various ECM proteins are found brominated in healthy conditions in both mouse and human lungs.