1. Fibrotic extracellular matrix induces release of extracellular vesicles with pro-fibrotic miRNA from fibrocytes.
- Author
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Sato S, Chong SG, Upagupta C, Yanagihara T, Saito T, Shimbori C, Bellaye PS, Nishioka Y, and Kolb MR
- Subjects
- Animals, Bronchoalveolar Lavage Fluid cytology, Coculture Techniques, Disease Models, Animal, Disease Progression, Extracellular Vesicles metabolism, Humans, Rats, Rats, Sprague-Dawley, Transforming Growth Factor beta1 pharmacology, Up-Regulation, Extracellular Matrix metabolism, Fibroblasts metabolism, MicroRNAs metabolism, Pulmonary Fibrosis metabolism
- Abstract
Rationale: Extracellular vesicles (EVs) are small lipid vesicles, and EV-coupled microRNAs (miRNAs) are important modulators of biological processes. Fibrocytes are circulating bone marrow-derived cells that migrate into the injured lungs and contribute to fibrogenesis. The question of whether EV-coupled miRNAs derived from fibrocytes are able to regulate pulmonary fibrosis has not been addressed yet., Methods: Pulmonary fibrosis was induced in rats by intratracheal administration of an adenoviral gene vector encoding active transforming growth factor-β1 (TGF-β1) or control vector. Primary fibrocytes and fibroblasts were cultured from rat lungs and were sorted by anti-CD45 magnetic beads. Human circulating fibrocytes and fibrocytes in bronchoalveolar lavage fluid (BALF) were isolated by fibronectin-coated dishes. Fibrocytes were cultured on different stiffness plates or decellularised lung scaffolds. We also determined the effects of extracellular matrix (ECM) and recombinant TGF-β1 on the cellular and EV-coupled miRNA expression of fibrocytes., Results: The EVs of fibrocytes derived from fibrotic lungs significantly upregulated the expression of col1a1 of fibroblasts. Culturing on rigid plates or fibrotic decellularised lung scaffolds increased miR-21-5 p expression compared with soft plates or normal lung scaffolds. Dissolved ECM collected from fibrotic lungs and recombinant TGF-β1 increased miR-21-5 p expression on fibrocytes, and these effects were attenuated on soft plates. Fibrocytes from BALF collected from fibrotic interstitial pneumonia patients showed higher miR-21-5 p expression than those from other patients., Conclusions: Our results indicate that ECM contributes to fibrogenesis through biomechanical and biochemical effects on miRNA expression in fibrocytes., Competing Interests: Competing interests: MRJK reports grants and personal fees from the Canadian Institute for Health Research (PJT-162295), Roche, Boehringer Ingelheim, GSK, Gilead, Prometic, Alkermes, Actelion, Respivert and Synairgen., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2021
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