Abstract
Purpose :
Posterior capsule opacification (PCO) commonly develops following cataract surgery and is a wound-healing response that can ultimately lead to secondary visual loss. Improved management of this problem is required. The isothiocyantae, sulforaphane (SFN), is reported to exert cytoprotective and cytotoxic actions and the latter may be exploited to treat/prevent PCO. Previous work has shown that SFN can increase MAPK signalling, autophagy and cell death. SFN is also reported to increase reactive oxygen species (ROS) levels. The current study, therefore, aimed to evaluate the role of ROS in the physiological events associated with SFN in lens epithelial cells.
Methods :
To assess the effects of SFN on lens epithelial cells, the human lens epithelial cell line FHL124 and capsulorhexis samples generated from human donor eyes by simulated cataract surgery were employed. The MTS assay was used to assess cell viability and the LDH assay was employed to assess cell damage/death. Protein levels were determined using western blot. N-acetyl cysteine (NAC) was used to scavenge ROS.
Results :
Application of 50µM SFN significantly reduced viability and promoted cell death of both FHL124 cells and native lens epithelial cells present on capsulorhexis samples. Pre-treating either cell or tissue preparations with 100µM NAC prevented SFN-induced cell death and loss of viable cells. To further investigate the mechanisms linking ROS to SFN-induced cell death we utilised the FHL124 cell line. 50µM SFN significantly induced elevated levels of the autophagy marker LC3-II. This increase was prevented by pre-treatment with 100µM NAC. SFN is also reported to drive MAPK signalling through ERK, and again, pre-treatment with NAC reduced SFN-induced ERK phosphorylation.
Conclusions :
Our investigations support previous findings that show SFN is capable of inducing autophagy and cell death. ROS appears to play a key role in SFN mediated responses. SFN is a potential therapeutic agent for PCO.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.