The Endothelial-mesenchymal Transition in Systemic Sclerosis Is Induced by Endothelin-1 and Transforming Growth Factor-β and May Be Blocked by Macitentan, a Dual Endothelin-1 Receptor Antagonist

• Published in: Journal of rheumatology 2015-10, Vol.42 (10), p.1808-1816
• Main Authors: Cipriani, Paola, Di Benedetto, Paola, Ruscitti, Piero, Capece, Daria, Zazzeroni, Francesca, Liakouli, Vasiliki, Pantano, Ilenia, Berardicurti, Onorina, Carubbi, Francesco, Pecetti, Gianluca, Turricchia, Stefano, Alesse, Edoardo, Iglarz, Marc, Giacomelli, Roberto
• Format: Article
• Language: English
• Subjects: Adult; Biomarkers - metabolism; Case-Control Studies; Cell Transdifferentiation - drug effects; Cell Transdifferentiation - physiology; Cells, Cultured - drug effects; Cells, Cultured - metabolism; Endothelial Cells - drug effects; Endothelial Cells - metabolism; Endothelin-1 - metabolism; Enzyme-Linked Immunosorbent Assay; Female; Humans; Italy; Male; Pyrimidines - pharmacology; Reference Values; Scleroderma, Systemic - blood; Scleroderma, Systemic - drug therapy; Sensitivity and Specificity; Statistics, Nonparametric; Sulfonamides - pharmacology; Transforming Growth Factor beta - metabolism; Young Adult
• ISSN: 0315-162X; 1499-2752
• DOI: 10.3899/jrheum.150088

High endothelin-1 (ET-1) and transforming growth factor-β (TGF-β) levels may induce in healthy endothelial cells (EC) an endothelial-to-mesenchymal transition (EndMT). The same cytokines are associated with fibrosis development in systemic sclerosis (SSc). Although EndMT has not been definitively shown in SSc, this process, potentially induced by a stimulatory loop involving these 2 cytokines, overexpressed in this disease might contribute to fibroblast accumulation in affected tissues. Macitentan (MAC), an ET-1 receptor antagonist interfering with this loop, might prevent EndMT and fibroblast accumulation. EC, isolated from healthy controls (HC) and patients with SSc, were treated with ET-1 and TGF-β and successively analyzed for gene and protein expressions of endothelial and mesenchymal markers, and for Sma- and Mad-related (SMAD) phosphorylation. Further, in the supernatants, we evaluated ET-1 and TGF-β production by ELISA assay. In each assay we evaluated the ability of MAC to inhibit both the TGF-β and ET-1 effects. We showed that both TGF-β and ET-1 treatments induced an activation of the EndMT process in SSc-EC as reported in HC cells. The ELISA assays showed a mutual TGF-β and ET-1 induction in both SSc-EC and HC-EC. A statistically significant increase of SMAD phosphorylation after treatment was observed in SSc-EC. In each assay, MAC inhibited both TGF-β and ET-1 effects. Our work is the first demonstration in literature that SSc-EC, under the synergistic effect of TGF-β and ET-1, may transdifferentiate toward myofibroblasts, thus contributing to fibroblast accumulation. MAC, interfering with this process in vitro, may offer a new potential therapeutic strategy against fibrosis.