Objective To observe the influence of triamcinolone acetonide (TA) on the expression of pigment epitheliumderived factor (PEDF) of human retinal pigment epithelial (RPE) cells. Methods Cultured humanRPE cells (4th－6th generations) were treated with four different concentrations of TA (40, 400, 4times;103 and 4times;104 mu;g/L) for three different periods (12 or 24 or 48 hours), the levels of PEDF protein in the cell culture supernatant and cell lysates were determined by Western blot. After the initial experiment, RPE cells were treated with or without tumor necrosis factor-alpha; (TNF-alpha;, 20 ng/ml） for 24 hours, followed by TA (400 mu;g/L) treatment. The levels of PEDF and phospho-p38 mitogen activated protein kinase(p-p38MAPK) protein expression in cell culture supernatant and cell lysates were measured by Western blot. Results TAtreated RPE cells had higher PEDF expression, and 400 mu;g/L TA group had the highest effect (F＝16.98,P＜0.05). 400 mu;g/L TA treatment for one, six or 24 hours, with or without TNF-alpha; pretreatment, could all promote the PEDF expression and inhibit the p-p38MAPK protein expression (F＝16.87, 10.28; P＜0.01). TNF-alpha; pretreatment alone could inhibit PEDF protein expression and promote p-p38MAPK protein expression (F=16.87, 10.28; P＜0.01). Conclusions TA can up-regulate the expression of PEDF, and downregulate the expression of p-p38MAPK in the cultured human RPE cells.
ObjectiveTo investigate the cytotoxicity of triamcinolone acetonide (TA) on cultured human retinal pigment epithelial (RPE) cells.MethodsEffect of TA with different concentraion (0.4, 02, 01, 0.05, and 0.025 mg/ml) on the proliferation of RPE cells was detected by methyl thiazolyl tetrazolial (MTT) assay; The changes of cellular cycle treated by TA with the drug concentration of IC50 for 72 hours were measured by flow cytometry (FCM) ananlysis, and the morphological and ultrastructural changes of the cells were observed by phasecontrast microscopy and transmission electron microscopy.ResultsWith the concentration of 0.4-0.025 mg/ml, TA inhibited the growth of RPE cells obviously in a dose-dependent manner compared with the control (P＜0.05), and the cells in S phase treated with TA decreased 10.6% compared with the control (P＜0.05). Under the light microscope, sparse cells with irregular configuration and many prominences and cellular vacuoles in TA group can be seen. The results of transmission electron microscopy showed asymmetrically distributed cellular chromatin was, cavitated cytoplasm, and even some necrotic cells.ConclusionTA can inhibite the S-phase karyomitosis of RPE and inhibite the cellular proliferation; and destroye the cellular structure and lead to the necrosis, which indicates the cytotoxicity of TA on RPE.(Chin J Ocul Fundus Dis, 2005,21:233-236)