Nintedanib downregulates the transition of cultured systemic sclerosis fibrocytes into myofibroblasts and their pro-fibrotic activity

Abstract

Background Circulating fibrocytes are an important source of fibroblasts and myofibroblasts, which are involved in fibrotic processes, including systemic sclerosis (SSc). The study aimed to investigate the effect of nintedanib (a tyrosine kinase inhibitor) in inhibiting the in vitro transition of circulating SSc fibrocytes into myofibroblasts and their pro-fibrotic activity. Methods Circulating fibrocytes were obtained from 18 SSc patients and 5 healthy subjects (HSs). Cultured SSc fibrocytes were maintained in growth medium (untreated cells) or treated with nintedanib 0.1 and 1 μM for 3 and 24 h. Fibroblast-specific protein-1 (S100A4) and α-smooth muscle actin (αSMA), as markers of fibroblast/myofibroblast phenotype, together with type I collagen (COL1) and fibronectin (FN), were investigated by qRT-PCR and Western blotting. Non-parametric tests were used for statistical analysis. Results Significantly elevated gene and protein expressions of αSMA, S100A4, COL1, and FN were observed in SSc fibrocytes compared to HS fibrocytes (gene: αSMA p < 0.001; others p < 0.0001; protein: all p < 0.05). Interestingly, an increased gene and protein expression of αSMA and S100A4 was found in fibrocytes from SSc patients positive for anti-Scl70 and with interstitial lung disease (ILD) (Scl70+ILD+) compared to Scl70−ILD− patients (S100A4: gene: p < 0.01; protein: p < 0.05), whereas no differences were observed for COL1 and FN. Nintedanib reduced gene and protein expression of αSMA, S100A4, COL1, and FN in SSc fibrocytes compared to untreated ones with different statistical significance. Noteworthy, nintedanib significantly downregulated gene and protein expression of αSMA, S100A4, COL1, and FN in Scl70+ILD+ fibrocytes (all p < 0.05), whereas only that of S100A4 and FN was significantly downregulated (p < 0.05) in Scl70−ILD− fibrocytes compared to the related untreated cells. Conclusions Nintedanib seems to downregulate in vitro the transition of fibrocytes into myofibroblasts and their pro-fibrotic activity, particularly in cells isolated from Scl70+ILD+ SSc patients.

Secreted S100A4 causes asthmatic airway epithelial barrier dysfunction induced by house dust mite extracts via activating VEGFA/VEGFR2 pathway

“…Thus there exists not only the quantity difference, but also the activity difference possibly in S100A4 inside and outside cells. Patients with systemic sclerosis were found to have over‐expression S100A4 protein in their skin, resulting from the effect of fibroblasts 34 . And in the model of mice with systemic sclerosis, transforming growth factor (TGF)‐β was shown to be one of S100A4 activators via Smad3‐dependent pathway 14 .…”

“…Patients with systemic sclerosis were found to have overexpression S100A4 protein in their skin, resulting from the effect of fibroblasts. 34 And in the model of mice with systemic sclerosis, transforming growth factor (TGF)-β was shown to be one of S100A4 activators via Smad3-dependent pathway. 14 In terms of patients with psoriasis, their expression of S100A4 in various types of dermis cells was up-regulation.…”

Therapeutic Options for Systemic Sclerosis: Current and Future Perspectives in Tackling Immune-Mediated Fibrosis

“…Nintedanib may also exert its anti-fibrotic efficacy by restraining the migration and differentiation of fibroblasts and fibrocytes. Interestingly, in vitro data have shown that nintedanib downregulates the transition of fibrocytes towards myofibroblasts, and thus the pro-fibrotic effect of the latter is reduced [ 197 , 198 ]. Nintedanib has received FDA approval for the treatment of IPF.…”

Nintedanib ameliorates osteoarthritis in mice by inhibiting synovial inflammation and fibrosis caused by M1 polarization of synovial macrophages via the MAPK/PI3K‐AKT pathway

“…In murine models of lung fibrosis, nintedanib inhibited macrophage and fibroblast activation and prevented fibrocyte migration 19–21 . In addition, nintedanib reduced the transition of fibrocytes to myofibroblasts and its pro‐fibrotic activity 22 . Nintedanib has been found to protect chondrocytes against tumor necrosis factor alpha‐induced degradation of the extracellular matrix against osteoarthritis 23 .…”

“…[19][20][21] In addition, nintedanib reduced the transition of fibrocytes to myofibroblasts and its pro-fibrotic activity. 22 Nintedanib has been found to protect chondrocytes against tumor necrosis factor alpha-induced degradation of the extracellular matrix against osteoarthritis. 23 Synovial inflammation and fibrosis are also important pathological manifestations of OA, does nintedanib reduce OA by inhibiting synovial inflammation and fibrosis?…”