CGRP induces myofibroblast differentiation and the production of extracellular matrix in MRC5s via autocrine and paracrine signalings

• Published in: Journal of biochemical and molecular toxicology 2022-12, Vol.36 (12), p.e23204-n/a
• Main Authors: Kayalar, Ozgecan, Oztay, Fusun
• Format: Article
• Language: English
• Subjects: Actin; Autocrine signalling; Calcitonin; Calcitonin gene-related peptide; Calcitonin Gene-Related Peptide - metabolism; Cell Differentiation; Cell growth; Cell lines; Cell proliferation; CGRP; Collagen; Collagen (type I); Differentiation; Dkk1 protein; Extracellular matrix; Extracellular Matrix - metabolism; Fibroblasts - metabolism; Fibronectin; Fibrosis; Growth factors; Humans; Kinases; Lung diseases; Mesenchyme; MRC5 and A549; Muscles; Myofibroblasts - metabolism; Myofibroblasts - pathology; Paracrine Communication; Paracrine signalling; pulmonary fibrosis; Signaling; Smad protein; Smad2 protein; Smad4 protein; Smooth muscle; TGF‐β; Transforming Growth Factor beta - metabolism; Transforming Growth Factor beta1 - metabolism; Transforming growth factor-b; Wnt protein; Wnt signaling; Wnt Signaling Pathway
• ISSN: 1095-6670; 1099-0461
• DOI: 10.1002/jbt.23204

There are contradictory views on which calcitonin gene‐related peptide (CGRP) causes pulmonary fibrosis. Fibrotic potency of CGRP was tested and compared to that of transforming growth factor‐β (TGF‐β). Myofibroblast differentiation, cell proliferation, and activations of TGF‐β and Wnt pathways were examined for 24, 48, and 72 h in A549 and MRC5 cell lines stimulated with CGRP and TGF‐β. CGRP‐induced cell proliferation in MRC5s early on while cell proliferation in A549 occurred progressively. CGRP promoted fibroblast‐myofibroblast differentiation by inducing the transcription of ACTA2, COL1A1, SMAD2/3, and SMAD4 genes, the production of collagen, fibronectin, α‐smooth muscle actin, and activation of TGF‐β signaling starting from 24 h. Additionally, TGF‐β signaling induced by CGRP decreased the DKK1 level and activated the Wnt signaling in MRC5s. After CGRP stimulation, Wnt7a levels were increased from 24 to 72 h, while Wnt5a levels were elevated at 72 h in MRC5s. CGRP did not induce epithelial–mesenchymal transition in A549s, unlike TGF‐β. A comparison of fibrotic potency of CGRP and TGF‐β showed that TGF‐β is a powerful profibrotic molecule and induces earlier myofibroblast differentiation. Even so, CGRP promotes myofibroblast differentiation and extracellular matrix production by inducing Smad‐dependent‐TGF‐β and Wnt signalings via autocrine and paracrine signalings in MRC5s.