Determination of Oxidative Stress Markers in the Aqueous Humor and Corneal Tissues of Patients With Congenital Hereditary Endothelial Dystrophy

Purpose: The aim of this study is to determine the presence of oxidative stress markers in the aqueous humor (AH) and corneal tissues of patients with congenital hereditary endothelial dystrophy (CHED). Methods: Interventional prospective study was undertaken to quantify levels of ascorbic acid and glutathione in the AH of patients with CHED. AH was collected from patients undergoing keratoplasty and levels of ascorbic acid and glutathione were determined using biochemical assays and measured spectrophotometrically. AH collected from pediatric patients with cataract were used as control. Corneal sections of patients who underwent penetrating keratoplasty were obtained, and presence of glutathione peroxidase 1, catalase, and superoxide dismutase was determined by immunohistochemistry. Tissue sections obtained from cadaveric corneas unsuitable for clinical transplant were used as control. Results: Significantly increased ascorbic acid levels were determined in patients with CHED (605.6 +/- 158.9 mu M) compared with those in controls (190.5 +/- 74.72 mu M). However, a trend toward reduced level of glutathione was detected in patients with CHED compared with that in the controls. Increased glutathione peroxidase 1 staining and reduced expression of catalase was detected in corneal tissues of patients with CHED compared with those in control corneal tissues. There was no apparent changes observed in the expression of superoxide dismutase in the corneal sections obtained from patients with CHED. Conclusions: To the best of our knowledge, this is the first study to determine the levels of ascorbic acid and glutathione in AH of patients with CHED. Our data suggest the presence of oxidative stress in CHED that might be responsible for the pathological changes in patients with CHED.