Effects of yellow intraocular lenses on light-induced upregulation of vascular endothelial growth factor

To investigate the protective effect of a blue-light filtering intraocular lens (yellow IOL) (YA60BB, Hoya) and an ultraviolet (UV)-absorbing IOL (VA60BB, Hoya) on light-induced phototoxicity to retinal pigment epithelial (RPE) cells laden with the lipofuscin fluorophore A2E and on the production of vascular endothelial growth factor (VEGF) after light exposure.

University of Tokyo, Tokyo, Japan.

The A2E-laden ARPE-19 cells were exposed to white light and a UV-absorbing IOL or a blue-light filtering IOL was placed over the light beam. After 48 hours of irradiation, the viability of the cells was determined with WST-1 (a sodium salt of 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate) assay, and the secreted protein level of VEGF was determined by enzyme-linked immunosorbent assay.

Without an IOL, the white-light exposure decreased cell viability to 28% of the nonirradiated control. Although the UV-absorbing IOL tended to reduce light-induced cell death, the decrease was not significant. However, the presence of the blue-light filtering IOL significantly attenuated light-induced cell damage, increasing cell viability to 42%. The secreted VEGF protein level increased 3.2-fold after the A2E-laden RPE cells were exposed to white light. In the presence of the UV-absorbing IOL, the VEGF protein level decreased, but not significantly. The presence of the blue-light filtering IOL significantly attenuated the upregulated VEGF expression compared to upregulation without an IOL.

This study supports the theory that a blue-light filtering IOL may be more protective against A2E-induced photochemical damage and inhibit more light-induced VEGF production than a conventional UV-absorbing IOL.