Abstract:

Objective Observing the changes of human trabecular cell viability and expression of genes involved in aqueous humor outflow regulation under the strong mechanical stretch. Design Experimental study. Participants Human trabecular meshwork cells（HTMCs）. Methods The HTMCs were divided into three groups: 0 h control, 12 h and 24 h according to the stretch time. Cultured HTMCs were subjected cyclic stretch on the Flexcell Strain system at a level of 22% increment in surface area for 12, 24 hours. The AV-PI method was used to detect the apoptosis rate of HTMCs. Western-blotting was used to detect the expression of signal pathway protein related to survive, and qPCR was used to detect the expression of the genes related to the regulation of aqueous outflow. Main Outcome Measures The apoptosis rate of HTMCs, the expression of integrin-Fak-Akt cell signaling pathway, the expressions of 15 genes related to aqueous humor outflow regulation. Results Compared the HTMCs undergoing the mechanical stretch (0, 12, 24 h), the apoptosis rate was 0.71%±0.18%, 0.77%±0.19%, 0.87%±0.31%, respectively (P=0.7298). The phosphorylated Akt was 1.00, 2.17±0.06, 1.69±0.07, respectively (P<0.01). The phosphorylated Fak397 was 1.00, 1.85±0.09, 1.31±0.08, respectively (P<0.01). At the same time, the expression of matrix metalloproteinases (1, 2, 3, 7, 9, 10, 11, 12, 14) increased (all P<0.01). The expression of metallopeptidase inhibitor (1, 2, 3) decreased (all P<0.01). And the expression of IL-6 was 1.00, 1.28±0.06, 1.47±0.06, respectively（P<0.01）. Conclusion High strength mechanical stretch can increase the vitality of trabecular meshwork cells and promote the secretion of aqueous outflow regulation related factors. This may be one of the mechanisms of canaloplasty to reduce the intraocular pressure.

Key words: human trabecular meshwork cell, canaloplasty, matrix metalloproteinases, mechanical stretch