Pivotal role of FARP2 in TGF-β1-mediated myofibroblast differentiation and corneal fibrosis.

Corneal stromal fibrosis represents a major cause of visual impairment, primarily driven in part by the TGF-β1-mediated transition of stromal fibroblasts into contractile myofibroblasts. FARP2, a mediator of Rho-GTPase signaling and cytoskeletal organization, has been proposed as a potential mediator of this phenotypic transition; however, the specific functional contribution stromal remodeling remains largely undefined) its functional role in corneal stromal remodeling remains unclear. CSFs were isolated from New Zealand rabbits and cultured under standard conditions. Myofibroblast differentiation was induced using recombinant TGF-β1 (5 and 20 ng/mL). Gene silencing of FARP2 was performed using sequence-specific siRNA. Gene expression levels of FARP2, RHOA, TLN1, SLC2A4 and the fibrotic extracellular matrix marker COL1A were quantified by Real-time PCR and expressed as log2 fold change and FARP2 protein expression was assessed by Western blotting. The alpha smooth muscle actin (α-SMA) expression was evaluated by immunocytochemistry, and cell migratory capacity was analyzed using the scratch assay. TGF-β1 treatment induced distinct myofibroblast-like morphological changes and significantly increased α-SMA expression. In parallel, TGF-β1 significantly upregulated COL1A1 expression, indicating enhanced extracellular matrix remodeling. TGF-β1 also upregulated FARP2, RHOA, TLN1, and SLC2A4 expression in a dose-dependent manner (p < 0.05). FARP2 knockdown effectively suppressed these transcriptional responses and markedly reduced FARP2 protein levels (p < 0.05). In the scratch assay, TGF-β1 significantly enhanced wound closure kinetics, whereas FARP2 silencing resulted in a pronounced reduction in cell migration and delayed wound repair (p < 0.0001). Additionally, glucose- and TGF-β-induced upregulation of SLC2A4 was substantially attenuated in the absence of functional FARP2. These findings highlight FARP2 as a potential therapeutic candidate. Targeting of FARP2 may represent a promising therapeutic approach for preventing or reducing corneal fibrosis and scar formation.