Type I collagen induces mesenchymal cell differentiation into myofibroblasts through YAP-induced TGF-β1 activation

• Published in: Biochimie 2018-07, Vol.150, p.110-130
• Main Authors: Liu, Xiaoling, Long, Xinyu, Liu, Weiwei, Zhao, Yeli, Hayashi, Toshihiko, Yamato, Masayuki, Mizuno, Kazunori, Fujisaki, Hitomi, Hattori, Shunji, Tashiro, Shin-ichi, Ogura, Takaaki, Atsuzawa, Yuji, Ikejima, Takashi
• Format: Article
• Language: English
• Subjects: 3T3-L1 Cells; Adaptor Proteins, Signal Transducing - genetics; Adaptor Proteins, Signal Transducing - metabolism; Animals; Blotting, Western; Cell Cycle Proteins; Cell Differentiation - genetics; Cell Differentiation - physiology; Cell Line; Cell Proliferation - genetics; Cell Proliferation - physiology; Collagen Type I - genetics; Collagen Type I - metabolism; ECM remodeling; Enzyme-Linked Immunosorbent Assay; Fibroblasts - cytology; Fibroblasts - metabolism; Flow Cytometry; Mesenchymal cell; Mice; Microscopy, Confocal; Myofibroblast; Myofibroblasts - cytology; Myofibroblasts - metabolism; Oxidative stress; Phosphoproteins - genetics; Phosphoproteins - metabolism; Transforming Growth Factor beta1 - genetics; Transforming Growth Factor beta1 - metabolism; YAP
• ISSN: 0300-9084; 1638-6183
• DOI: 10.1016/j.biochi.2018.05.005

In organ fibrosis, mechanical stress and transforming growth factor beta-1 (TGF-β1) promote differentiation into myofibroblast from mesenchymal cells, leading to extracellular matrix (ECM) remodeling or active synthesis, deposition or degradation of ECM components. A major component of ECM, type I collagen (col I) triple helical molecules assemble into fibrils or are denatured to gelatin without triple-helicity in remodeling. However, whether changes of ECM components in remodeling have influence on mesenchymal cell differentiation remains elusive. This study adopted three states of collagen I existing in ECM remodeling: molecular collagen, fibrillar collagen and gelatin to see what are characteristics in the effects on two cell lines of mesenchymal origin, murine 3T3-L1 embryonic fibroblast and murine C2C12 myoblasts. The results showed that all three forms of collagen I were capable of inducing these two cells to differentiate into myofibroblasts characterized by increased expression of alpha-smooth muscle actin (α-SMA) mRNA. The expression of α-SMA is positively regulated by TGF-β1. Nuclear translocation of Yes-associated protein (YAP) is involved in this process. Focal adhesion kinase (FAK) is activated in the cells cultured on molecular collagen-coated plates, contributing to YAP activation. On the other hand, in the cells cultured on fibrillar collagen gel or gelatin-coated plates, oxidative stress but not FAK induce YAP activation. In conclusion, the three physicochemically distinct forms of col I induce the differentiation of mesenchymal cells into myofibroblasts through different pathways. •Molecular collagen induced the formation of myofibroblasts by FAK activation.•Fibrillar collagen and gelatin induced the myofibroblasts differentiation by ROS.•YAP-induced the release of TGF-β1 played a necessary role in these processes.