Abstract
Purpose: :
Blue light induces apoptosis in human fetal retinal pigment epithelium (HFRPE) cells which depends on several factors. Damage of RPE cells is a main factor in development and progression of age-related macular degeneration. In this study we examined the effect of free radical chemistry on apoptosis in the presence of static magnetic field.
Methods: :
Retinal pigment epithelium cells were isolated from human fetal eyes and pure cultures were obtained. Purity of cells was confirmed with cytokeratin assay. HFRPE cells of the fifth passage were illuminated at confluence with blue light with the intensity of 4.5 mW/cm2 for 7 days in an especially designed incubator in the presence or absence of static magnetic field. The rate of apoptosis induced by blue light irradiation was analyzed by Annexin V staining using flow cytometry techniques. The cells incubated in the dark served as control samples.
Results: :
The apoptosis rate of HFRPE cells depends on culturing time at confluence and the illumination time with blue light. HFRPE cells in the presence of magnetic field of about 1000 Gauss exhibit much lower rate of apoptosis as compared to the cells illuminated with blue light without magnetic field.
Conclusions: :
The decrease in light induced apoptosis of HFRPE cells due to static magnetic field provides evidence for involvement of free radical chemistry in cell necrosis.
Keywords: retinal pigment epithelium • cell survival • flow cytometry