Addition of ROCK inhibitors to prostaglandin derivative (PG) synergistically affects adipogenesis of the 3D spheroids of human orbital fibroblasts (HOFs).

To study the additive effects of Rho-associated coiled-coil containing protein kinase inhibitors, ripasudil (Rip) to bimatoprost acid (BIM-A) on orbital adipose tissue, three-dimensional (3D) cultures of human orbital fibroblasts (HOFs) were prepared and the physical properties including the 3D spheroid size and stiffness, lipid staining by BODIPY and the mRNA expression of adipogenesis-related genes, PPARγ and AP2, and extracellular matrix (ECM) including collagen (COL)1, 4 and 6, and fibronectin (FN) were analyzed. Adipogenesis (DIF+) induced (1) enlargement and increasing stiffness of the 3D HOFs spheroid, (2) increased lipid staining, the expression of adipogenesis-related gene expressions, and (3) the down-regulation of COL1 and FN and up-regulation of COL4 and COL6. In the presence of BIM-A, (1) such DIF+-induced changes in 3D spheroid size and stiffness were significantly inhibited or enhanced, respectively, (2) the lipid staining and its related gene expressions were significantly down-regulated, and (3) the expression of COL1 and COL6 were up-regulated. By the addition of Rip to BIM-A, the above BIM-A-induced effects were all inhibited, except for the up-regulation of COL6 and FN expression, that is, enlarging and decreasing stiffness, enhancement of lipid staining and its related gene expression, and down-regulation of COL1 expression. Our present study indicates that Rip significantly suppressed BIM-A-induced effects toward 3D HOFs spheroids.