PTEN Inhibition Accelerates Corneal Endothelial Wound Healing through Increased Endothelial Cell Division and Migration

Abstract

To investigate the role of phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in the regulation of corneal endothelial cell (CECs) focusing on proliferation and migration, and to further evaluate the application of PTEN inhibitors in the treatment of corneal endothelial dysfunction in a rat model. METHODS. Expression of PTEN in human and rat corneal endothelium was determined by immunocytochemistry, western blotting, and ELISA. A small molecular inhibitor of PTEN, bpV(pic), was applied in the culture of human CEC cell line B4G12 and organcultured rat cornea in the presence of transforming growth factor beta 2 (TGF-β2). Cell cycle status was detected by flow cytometry and BrdU staining. Subcellular localization for endogenous p27Kip1 was detected by immunocytochemistry and western blotting. Moreover, exogenous transfected YFP-p27Kip1 was observed under a fluorescent microscope. Cell migration was examined with a wound scratch model and transwell invasion assay. Finally, bpV(pic) was intracamerally injected in a rat corneal endothelial injury model. The wound healing process was evaluated by slit lamp biomicroscopy, optical coherence tomography, histological and scanning electron microscope examination. RESULTS. The expression of PTEN in human corneal endothelium was higher compared with rat, which we speculate was mostly responsible for the relatively less proliferation capacity of human CEC than rat. PTEN inhibition by bpV(pic) could reverse TGF-β2induced CEC G1-arrest by alleviating p27Kip1 nuclear accumulation and decreasing total p27Kip1 expression. In addition, bpV(pic) promoted CEC migration, which acted synergistically with TGF-β2. Finally, intracameral injection of bpV(pic) could promote corneal endothelial wound healing in a rat model. CONCLUSIONS. Our study provided experimental basis for the development of therapeutic agent targeting on PTEN for the treatment of corneal endothelial dysfunction.

PAX6, modified by SUMOylation, plays a protective role in corneal endothelial injury

“…For higher transfection efficiency, normal and injured mice corneas were isolated to be organ-cultured as previously described 33 . Ad-GFP (0.5 μL, 1 × 10 10 pfu, Control group) or Ad-PAX6 (0.5 μL, 1 × 10 10 pfu, PAX6 group) was added to the cultured injured corneas.…”

Corneal endothelial wound healing: understanding the regenerative capacity of the innermost layer of the cornea

“…47,74 Nuclear accumulation of p27kip1 is caused by the phosphatase and tensin homolog (PTEN) proteininduced inhibition of AKT phosphorylation. 77 Zhang et al showed that inhibition of PTEN results in a stimulation of cell cycle progression as well as an increased migration behavior of CEnCs which emphasize the effect on wound healing. 77 In general, PI3K and Akt modulate cell cycle progression, enhance cell survival, but may also cause EnMT induction with concomitant increase in motility together with aberrant ECM secretion.…”

MSCs-Derived miR-150-5p-Expressing Exosomes Promote Skin Wound Healing by Activating PI3K/AKT Pathway through PTEN

“…PTEN is related to the downregulation of the PI3K/AKT pathway and acts as an anti-tumor gene by mediating the cell cycle, apoptosis, and migration ( 29 ). PTEN inhibition has been demonstrated to accelerate wound healing in corneal endothelia by increasing the division and migration of endothelial cells ( 30 ). MiR-21-mediated inhibition of PTEN activated the PI3K/AKT pathway and contributed to skin wound healing ( 31 ).…”