AIM: TO investigate the effects of tranilast on proliferation of cultured human retinal pigment epithelial(RPE)cells in vitro.

METHODS: To treate them with different concentrations of tranilast 0(control group), 12.5, 25, 50, 100mg/L after culturing human retinal pigment epithelial cells(hRPE-19 cell line)3-5 generations. And then to observe cell morphology under inverted microscope combined with HE staining, identify the cell by keratin CK18. Detecting inhibition rate by MTT colorimetric method after the cells were treated with different concentrations of tranilast for 12h, 24h, 48h. The RPE cells were cultured with different concentrations of tranilast for 24h, then to measure the transforming growth factor β1(TGF-β₁)and platelet-derived growth factor receptor A protein(PDGFR-A)expressing by Western-Blot and immunohistochemical method.

RESULTS: The cell inhibition rate increased with the increase of concentration at the same time point(P<0.05). It shows a statistically significant difference. TGF-β₁ protein expression is in cell plasma and PDGFR-A protein in the cell membrane and cytoplasm, the expression of their amount was lowered with the increase of concentration of tranilast(P<0.05). It shows a statistically significant difference.

CONCLUSION: Tranilast could inhibit RPE proliferation, and it may be connected with the decreased TGF-β₁ and PDGFR-A protein expression.