Hydrodynamic forces influence the gene transcription of mechanosensitive intercellular junction associated genes in corneal endothelial cells.

Abstract Mechanicals forces are known to influence cell behavior. In vivo, the corneal endothelium is under the influence of various mechanical forces, such as intraocular pressure (IOP) and fluid flow. In this study, we used a corneal bioreactor to understand the effect of these hydrodynamic forces on the transcription of intercellular junctions associated genes in the corneal endothelium. Native and tissue-engineered (TE) corneal endothelium were cultured in a corneal bioreactor for 7 days with 16 mmHg IOP and 5 μl/ml of medium flow. RNA was harvested, and gene expression was quantified. Cells that were used to reconstruct the TE corneal endothelium were also seeded on plastic to characterize their cell morphology by calculating their circularity index. For native endothelia, hydrodynamic forces increased gene expression of GJA1 (connexin 43), CDH2 (N-cadherin), TJP1 (ZO-1), ITGAV (integrin subunit αv), ITGB5 (integrin subunit β5) and CTNND1 (p120-ctn) by 1.68 ± 0.40, 1.10 ± 0.27, 3.80 ± 0.56, 1.82 ± 0.33, 1.32 ± 0.21 and 3.04 ± 0.63, respectively. For TE corneal endothelium, this fold change was 1.72 ± 0.31, 1.58 ± 0.41, 6.18 ± 1.03, 1.80 ± 0.71, 1.77 ± 0.55, 2.42 ± 0.71. Furthermore, gene transcription fold changes (hydrodynamic/control) increased linearly with TE corneal endothelium cells population morphology with r = 0.83 for TJP1 (ZO-1) and r = 0.58 for CTNND1 (p120-ctn). In fact, the more elongated the cells populations were, the greater hydrodynamic conditions increased the transcription of TJP1 (ZO-1) and CTNND1 (p120-ctn). These results suggest that hydrodynamic forces contribute to the maintenance of tight and adherens junctions of native corneal endothelial cells, as well as to the formation of tight and adherens junctions of corneal endothelial cells that are in the process of forming a functional endothelial barrier.