Purpose:
The aim was to compare total oxidative stress (TOS), total antioxidant capacity (TAC), and paraoxonase (PON1), arylesterase (ARE), and lipid peroxidase (LPO) levels in the aqueous humor and concurrent venous blood serum and to evaluate the role of oxidative stress in the progression of diabetic retinopathy in diabetic and non-diabetic patients with cataract.
Material and Method:
Oxidative tissue and organ damage play a significant role in diabetes and related complications. A reduction in the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase has been reported in both blood and lens samples. PON1, ARE, and LPO are unreviewed antioxidant enzymes until now. We included diabetic and non-diabetic patients who were admitted to our clinic for complaints of hazy vision and who received the diagnosis of cataract. Patients were divided into 3 groups: group 1 - diabetic patients without retinopathy, group 2- with diabetic retinopathy, and group 3 - patients without systemic disease outside the diagnosis of cataract. A total of 78 patients (26 patients in each group) were enrolled in the study.
Results:
In this study, there was no statistically significant difference among the groups for TOS, TAC, PON1, ARE and LPO levels in aqueous humor. Although simultaneous venous blood serum results, TOS, TAC, PON1 and HbA1c levels in all 3 groups were found statistically significant, ARE and LPO were not statistically significant. When groups 1 and 2 were compared with control group, it was found that in group 1, PON 1 was statistically significantly low and HbA1c was high, while in group 2, TOS and HbA1c were high and TAC and PON 1 were low (p<0.05).
Discussion:
Oxidative stress indicator enzymes were determined to be positive in blood and negative in humor aquosus. In the present study, these enzymes were studied for the first time in aqueous humor, thus, further studies including subtypes in case of polymorphism are needed. (Turk J Ophthalmol 2012; 42: 47-52)
Keywords: Diabetic retinopathy, aqueous humor, oxidative stress, paraoxonase, arylesterase