Antagonistic effects of trasilast on proliferation and collagen synthesis induced by TGF-\sB₂ in cultured human trabecular meshwork cellsin cultured human trabecular meshwork cells

Abstract

Whether tranilast had antagonistic effect on proliferation inhibition and collagen synthesis promotion induced by TGF-\sB₂ in cultured human trabecular meshwork cells was investigated. Suspension of 1×10⁴ cultured human trabecular meshwork cells of 3–5 passage was distributed in each well of a 96-well disk and divided into control group and experimental group. After 24 h, 0 μg/ml (control), 12.5 μg/ml, 25 μg/ml, 50μg/ml tranilast with 3.2 ng/ml TGF-\sB₂ were added into the incubation medium. Another 24 h later, proliferation and collagen synthesis in cultured human trabecular meshwork cells were examined respectively by using tetrazolium-based semiautomated colormetric (MTT) assay and³H-proline incorporation with liquid scintillation technique. The results showed absorbance (A) values of the experimental groups were 0.9036±0.3017, 1.1361±0.1352, 1.2457±0.1524 according to the different concentrations of tranilast, and 0.8956±0.1903 of the control group. In comparison with the control group, 25 μg/ml (q=3.23,P<0.05), 50 μg/ml (q′=4.70,P<0.01) tranilast significantly antagonized the decrease of theA values induced by TGF-\sB₂ in the cultured human trabecular meshowrk cells. In comparison with the control group [817.37±124.21 cpm/10⁴ cells], 12.5 μg/ml (620.33±80.46 cpm/10⁴ cells,q′=4.26,P<0.05), 25 μg/ml (59.4.58±88.13 cpm/10⁴ cells,q′=4.81,P<0.01), 50 μg/ml (418.64±67.90 cpm/10⁴ cells,q′=8.62,P<0.01) tranilast significantly inhibited the incorporation of³H-proline into the cultured human trabecular meshwork cells promoted by TGF-\sB₂ in a dose-dependent manner. It was concluded that tranilast had the antagonistic effect on the proliferation inhibition and collagen synthesis promotion induced by TGF-\sB₂ in the cultured human trabecular meshwork cells.

Keywords

transforming growth factor / human / trabecular meshwork / cultured cell / proliferation / collagen

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