Filtering blue light reduces light-induced oxidative stress, senescence, and accumulation of extracellular matrix proteins in human retinal pigment epithelium cells.
Purpose: Cumulative light exposure is significantly associated with aging and the progression of age-related macular degeneration. To prevent the retina from blue-light damage in pseudophakia, blue-light-absorbing intraocular lenses (IOLs) have been developed. This study compares the possible protective effects of a blue-light-absorbing IOL to an untinted UV-absorbing IOL with regard to light-induced oxidative stress and senescence of human retinal pigment epithelium (RPE). Methods: As primary human RPE cells were exposed to white light, either a UV- and blue-light-absorbing IOL or UV-absorbing IOL was placed in the light beam. After 60 min of irradiation, cells were investigated by electron microscopy for viability, induction of intracellular reactive oxygen species, and senescence-associated β-galactosidase activity. Expression and secretion of matrix metalloproteinases 1 and 3 and their mRNA were determined by real-time PCR and enzyme-linked immunosorbent assay. Results: Light exposure induced structural damage, decreased RPE cell viability, and increased reactive oxygen species, senescence-associated β-galactosidase activity, and matrix metalloproteinases 1 and 3 expression and secretion. Although both types of IOL significantly reduced these effects, the protective effects of the UV- and blue-light-absorbing IOL were significantly stronger than those of the UV-absorbing IOL. Conclusions: The UV- and blue-light-absorbing IOL demonstrated significantly better protection against light-induced oxidative stress, senescence, and structural damage than the UV-absorbing IOL. These in vitro findings support the hypothesis that the UV- and blue-light-absorbing IOL may prevent retinal damage in clinical use.