Abstract
Purpose: :
To determine whether sea tangle (Laminaria japonica) extracts modulate heme oxygenase (HO)-1 expression in cultured human retinal pigment epithelial (RPE) cells.
Methods: :
RPE cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, after 24 hours incubation with hydrogen peroxide (H2O2) or sea tangle extracts. Cultured human RPE cells were incubated with different concentrations of H2O2, sea tangle extracts or both. After 24 hours of incubation, RT-PCR was performed to evaluate the expression of HO-1 mRNA.
Results: :
The viability of human RPE cells gradually decreased as increased concentration of sea tangle extracts or H2O2. Human RPE cells showed increased HO-1 mRNA expression when exposed to sea tangle extracts only or H2O2 only (p<0.05). When RPE cells were preincubated with sea tangle extracts and later exposed to H2O2, HO-1 mRNA expression was relatively lower (p<0.05).
Conclusions: :
Sea tangle extracts upregulate the expression of HO-1 mRNA in human RPE cells. And when human RPE cells are preincubated with sea tangle extracts, HO-1 mRNA expression is decreased compared with H2O2 exposure alone, suggesting that sea tangle extracts have antioxidative effects on human RPE cells.
Keywords: antioxidants • retinal pigment epithelium • retinal culture