TGF-β-induced activation of conjunctival fibroblasts is modulated by FGF-2 and substratum stiffness

• Published in: PloS one 2020-11, Vol.15 (11), p.e0242626-e0242626
• Main Authors: Matsumura, Tomoyo, Fujimoto, Tomokazu, Futakuchi, Akiko, Takihara, Yuji, Watanabe-Kitamura, Fumika, Takahashi, Eri, Inoue-Mochita, Miyuki, Tanihara, Hidenobu, Inoue, Toshihiro
• Format: Article
• Language: English
• Subjects: Actin; Actins - biosynthesis; Adaptor Proteins, Signal Transducing - metabolism; Antibodies; Biology and Life Sciences; Cell growth; Cell Line; Cell Proliferation; Cell Transdifferentiation; Collagen; Collagen (type I); Collagen Type I - biosynthesis; Conjunctiva; Experiments; Fibroblast growth factor 2; Fibroblast Growth Factor 2 - metabolism; Fibroblasts; Fibronectin; Gene Expression Regulation; Glaucoma; Growth factors; Humans; Kinases; Laboratories; Life sciences; Medicine and Health Sciences; Muscles; Myofibroblasts - cytology; Myofibroblasts - metabolism; Physical Sciences; Plates; Proteins; R&D; Research & development; Silicone resins; Silicones; Smooth muscle; Stiffness; Surgery; Transcription; Transcription Factors - metabolism; Transforming Growth Factor beta2 - metabolism; Transforming Growth Factor beta2 - pharmacology; Wound healing; Yes-associated protein
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0242626

This study aimed to investigate the effects of substratum stiffness on the sensitivity of human conjunctival fibroblasts to transforming growth factor (TGF)-β, and to explore the molecular mechanism of action. Human conjunctival fibroblasts were cultured on collagen-coated plastic or silicone plates. The stiffness of the silicone plates was 0.2 or 64 kPa. Cells were treated by 2.5 ng/mL TGF-β2 with or without fibroblast growth factor (FGF)-2 (0-100 ng/mL) for 24 h or 48 h. The protein expression levels were determined by Western blot analysis. Cell proliferation was assessed using the WST-8 assay. FGF-2 suppressed the TGF-β-induced expression of α-smooth muscle actin (SMA) and collagen type I (Col I), but not fibronectin (FN). Both FGF-2 and TGF-β2 increased cell proliferation without an additive effect. The induction of α-SMA by TGF-β2 was decreased on the soft substratum, without any change in the expression level or subcellular location of Yes-associated protein/transcriptional coactivator with PDZ-binding motif (YAP/TAZ). FGF-2 suppressed TGF-β-induced α-SMA expression even on the soft substratum. FGF-2 treatment and a soft substratum suppressed TGF-β-induced transdifferentiation of conjunctival fibroblasts into myofibroblasts. FGF-2 attenuated the TGF-β-induced expression of α-SMA, even on a soft substratum.