Purchase this article with an account.
B.J. Tripathi, W. Philips, R.C. Tripathi, K.V. Chalam; Sub–Solar Ultraviolet Radiation Decreases Cell Viability and Alters Gene Expression of Retinal Ganglion Cells . Invest. Ophthalmol. Vis. Sci. 2005;46(13):5252.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Concern of the public and eye professionals about the harmful effects of ultraviolet radiation on the retina prompted us to investigate whether exposure of cultured retinal ganglion cells to sub–solar ultraviolet (UV–B) affects their cell viability and gene expression. Methods: Confluent cultures of rat retinal ganglion cells were irradiated with UV–B for 15, 30, 60, 120, or 360 minutes at a dose of 0·60 J/cm/minute. Untreated cultures served as controls. Neutral red staining and light microscopy were used to assess the viability of the ganglion cells. The effect of UV–B radiation on the expression of apoptosis related and cell cycle arrest genes, including cytochrome C, Bax and Bcl–2, was analyzed by using reverse transcription–polymerase chain reaction and immunostaining. Results: The neutral red assay showed a time dependent suppression of cell viability after exposure to UV–B radiation, with greater reduction at 60, 120, and 360 minutes. An increase in cytochrome C expression was found in the retinal ganglion cells exposed to UV–B radiation for 360 minutes. Immunostaining and reverse transcription–polymerase chain reaction showed a minor increase of Bax expression in retinal ganglion cells after a 15–minute exposure. A significant exponential increase in the expression of Bax was noted after 30, 60, 120 and 360 minutes of UV–B exposure (P<0.01). Marked reduction of Bcl–2 expression was also observed after exposure to UV–B radiation for 60 minutes or longer as compared to controls (P=0.01). Conclusions: Exposure of cultured retinal ganglion cells to UV–B radiation induces a decrease in cell viability as well as an increased expression of apoptosis related genes in a time dependent manner. Our findings imply that prolonged ambient and iatrogenic sub–solar ultraviolet radiation could contribute to damage of retinal ganglion cells.
This PDF is available to Subscribers Only