Abstract
Abstract: :
Purpose: Pigmentation of the retinal pigment epithelium (RPE) may be protective against such processes as age related macular degeneration and other macular pathology. However, little is known about the control of melanin expression in the RPE, and the pharmacologic stimulation of melanin production in the RPE remains poorly understood. Prostaglandins have been found to increase melanin content in melanasomes of iris melanocytes. This study's purpose is to test the effect of prostaglandins and prostamides on melanin production in cultured RPE cells. Methods: Established human RPE cell lines hTERT-RPE1 and ARPE-19 were grown in low serum conditions and exposed to various conditions of Prostaglandin E1, Prostaglandin A2, Latanaprost, Bimatoprost, and Travoprost. Cells were maintained in culture and tested for melanin production at 1 to 6 weeks (and longer) in culture. Iris melanocytes were used as control cells. Melanin production was measured by spectrophotometric assay. In addition, RT-PCR will be used to detect differences in melanin transcription where protein production differences are detected. Results: Preliminary results suggest that prostaglandins may increase melanin production in cultured RPE cell lines. Ongoing long term cultures may confirm these observations. In addition, responses to various prostaglandins appear to be unequal in preliminary experiments and long-term cultures may substantiate these differences. Conclusion: Prostaglandins may provide a pharmacologic effect of increasing pigmentation of the RPE. These experiments will need to be tested in animal models, and the possibility of protection by the increased pigmentation could be tested in disease models.
Keywords: 567 retinal pigment epithelium • 390 drug toxicity/drug effects • 560 retinal culture