Abstract
Abstract: :
Purpose: This study examined the effect of leptin on the proliferation and migration of human retinal pigment epithelial (RPE) cells. Methods: Human fetal RPE cells were isolated and cultured in DMEM supplemented with 10% fetal calf serum (FCS). RPE (P6) cells (2.1 x 104 cells/well) were seeded on a 96-well culture plate and incubated with DMEM containing 10% FCS for 24 hours. The medium was then discarded and the cells were incubated in DMEM containing 10% FCS and various concentrations of leptin up to 450 ng/ml for 24 and 72 hours. Cell survival was determined using MTT (3-[4,5-dimethyl-thiazol-2-yl]-2,5-diphenyl-tetrazolium bromide). Cells incubated in medium without FCS were used as a negative control. The data was analyzed using ANOVA. In a Boyden chamber assay, human RPE cells (3 x 104 cells/well) were seeded in the upper chamber in DMEM containing 10% FCS. 800ml DMEM containing 10% FCS and 0-450ng leptin was added to the bottom chamber. After 5 hours, the cells were fixed in methanol and stained with Mayer's modified hematoxalin. Migrating cells were counted and the numbers compared. Negative controls contained neither leptin nor FCS. Results: Leptin increased human RPE cell proliferation in a dose dependent manner as early as 24 hours post leptin addition. At 72 hours, cell survival was greater in samples containing leptin concentrations of 150ng/ml or greater. Conclusion: Present finding suggest that Leptin promotes human RPE cell proliferation and migration and therefore may play a role in Diabetic Retinopathya and age-related macular degeneration. Supported by CIHR
Keywords: 308 age-related macular degeneration • 423 growth factors/growth factor receptors • 561 retinal degenerations: cell biology