Nabeela K. Dulull, Daniel A. Dias, Thilini R. Thrimawithana and Faith A.A. Kwa* Pages 237 - 253 ( 17 )
Background: In age-related macular degeneration, oxidative damage and abnormal neovascularization in the retina are caused by the upregulation of vascular endothelium growth factor and reduced expression of Glutathione-S-transferase genes. Current treatments are only palliative. Compounds from cruciferous vegetables (e.g. L-Sulforaphane) have been found to restore normal gene expression levels in diseases including cancer via the activity of histone deacetylases and DNA methyltransferases, thus retarding disease progression.
Objective: To examine L-Sulforaphane as a potential treatment to ameliorate aberrant levels of gene expression and metabolites observed in age-related macular degeneration.
Method: The in vitro oxidative stress model of AMD was based on the exposure of Adult Retinal Pigment Epithelium-19 cell line to 200μM hydrogen peroxide. The effects of L-Sulforaphane on cell proliferation were determined by MTS assay. The role of GSTM1, VEGFA, DNMT1 and HDAC6 genes in modulating these effects was investigated using quantitative real-time polymerase chain reaction. The metabolic profiling of L-Sulforaphane-treated cells via gas-chromatography massspectrometry was established. Significant differences between control and treatment groups were validated using one-way ANOVA, student t-test and post-hoc Bonferroni statistical tests (p<0.05).
Results: L-Sulforaphane induced a dose-dependent increase in cell proliferation in the presence of hydrogen peroxide by upregulating Glutathione-S-Transferase μ1 gene expression. Metabolic profiling revealed that L-Sulforaphane increased levels of 2-monopalmitoglycerol, 9, 12, 15,-(Z-Z-Z)- Octadecatrienoic acid, 2-[Bis(trimethylsilyl)amino]ethyl bis(trimethylsilyl)-phosphate and nonanoic acid but decreased β-alanine levels in the absence or presence of hydrogen peroxide, respectively.
Conclusion: This study supports the use of L-Sulforaphane to promote regeneration of retinal cells under oxidative stress conditions.
Age-related macular degeneration, glutathione-S-transferase, L-Sulforaphane, metabolomic profiling, oxidative stress, retinal pigment epithelium.
Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Discipline of Pharmacy, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083, Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC 3083