Effect of High Glucose on the Oxidative Stress in Trabecular Meshwork Cells

ABSTRACT

PURPOSE: To investigate the effect of high glucose (HG) on the oxidative stress in cultured human trabecular meshwork cells (HTMC). METHODS: Primarily cultured HTMC were exposed to low glucose (5 mM) and HG (25 mM) for 7 days. Additionally, 1 mM L-arginine, 5 mM DAHP, 10 microgram/ml insulin, 100 micrometer L-ascorbic acid, 10, and 100 micrometer sepiapterin were co-exposed. The cellular survival and nitric oxide (NO) production were assessed by MTT assay and Griess assay, respectively. Superoxide production was measured by modified cytochrome c assay. RESULTS: HG did not affect the survival of cultured HTMC significantly. HG decreased NO production. Co-exposed DAHP decreased but DAHP and insulin increased NO production. In addition, HG increased superoxide production, which was decreased by insulin, L-ascorbic acid, and sepiapterin. CONCLUSIONS: HG decreased NO production accompanied with increased superoxide production in HTMC. Thus HG induces oxidative stress in HTMC and may cause cellular dysfunction and damage of the trabecular meshwork.