ROCK inhibitors beneficially alter the spatial configuration of TGFβ2-treated 3D organoids from a human trabecular meshwork (HTM)

To elucidate molecular pharmacology of Rho-associated coiled-coil containing protein kinase inhibitors (ROCK-i, Ripasudil and Y27632) on their efficiency for aqueous outflow, 2D or 3D cultures of a human trabecular meshwork (HTM) were prepared in the presence of TGFβ2. Those were examined by transendothelial electrical resistance (TEER, 2D), electronic microscopy (EM, 2D and 3D), expression of the extracellular matrix (ECM) including collagen1 (COL1), COL4 and COL6, and fibronectin (FN) by immunolabeling and/or quantitative PCR (3D), and solidity of 3D organoids by a micro-squeezer. TGFβ2 significantly increased the TEER values in 2D cultures, and the ECM expression indicated that the 3D organoids assumed a more densely packed shape. ROCK-i greatly reduced the TGFβ2-induced enhancement of TEER and the immunolabeled ECM expression of the 3D organoids. In contrast, the mRNA expression of COL1 was increased, and those of COL4 and FN were unchanged. EM revealed that TGFβ2 caused the HTM cells to become more compact and abundant ECM deposits within the 3D organoids were observed. These were significantly inhibited by ROCK-i. The dense solids caused by the presence of TGFβ2 were significantly suppressed by ROCK-i. Current study indicates that ROCK-i cause beneficial effects toward the spatial configuration of TGFβ2-induced HTM 3D organoids.