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Abstract
Purpose:
To investigate the effects of dexamethasone (DEX) on the production of nitric oxide (NO) and its enzymatic synthetic pathway in cultured human trabecular meshwork (HTM) cells.
Methods:
Primarily cultured HTM cells were exposed to 0, 10, 100, 1000 nM of DEX for 3 days. In addition, 100 μ M sepiapterin, 100 μ M ascorbic acid, and 10 μ M methotrexate were co-exposed to DEX. The cellular survival and nitrite production rates were assessed by MTT assay and Griess assay, respectively.
Results:
DEX did not significantly affect the survival of cultured HTM cells. DEX decreased the NO production in a dose− dependent manner. With co-exposure of DEX, ascorbic acid nullified the DEX-induced decrease of NO production. Sepiapterin and methotrexate did not affect DEX-induced decrease of NO production.
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Figure 1.
Effect of dexamethasone on the survival of cultured trabecular meshwork cells. Three-day exposure of dexamethasone did not significantly affect the survival of trabecular meshwork cells compared to non-exposed control (p>0.05).
Figure 2.
Effect of dexamethasone on the production of nitric oxide in cultured trabecular meshwork cell exposed for 3 days. Dexamethasone decreased nitric oxide production (∗ p<0.05).
Figure 3.
Effect of 100 μM sepiapterin on the production of nitric oxide after co-exposed to dexamethasone for 3 days. Sepiapterin further decreased nitric oxide production compared to non-exposed control (∗ p<0.05).
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