Abstract
Abstract: :
Purpose: To identify serum cytokines and chemokines linked to the development of more severe diabetic retinopathy with concurrent ischemic changes and/or diabetic macular edema. Method: Blood was drawn from 61 diabetic patients who had fasted and who had varying degrees of diabetic retinopathy undergoing an ocular exam and fundus photographs of 7 stereoscopic fields. Serum levels of cytokines were measured by ELISA using kits from R&D and Endogen. The following cytokines were measured: RANTES, ENA-78, IP-10, SDF1α, VEGF, ICAM, IL-8, MCP1, MIP-1α, VCAM, and IL-6. Serum levels of hemoglobin A1c, total cholesterol, triglycerides, HDL, LDL and creatinine and urinalysis were also assessed. The data were evaluated according to the presence or absence of retinal ischemia or diabetic macular edema. The retinal ischemia analysis comprised two groups consisting of patients currently without retinal ischemia: no retinopathy, mild to moderate non-proliferative diabetic retinopathy (NPDR) or quiescent proliferative diabetic retinopathy (PDR) and patients with retinal ischemia: severe NPDR, low-risk PDR, or high-risk PDR; The macular edema analysis also divided patients into two groups; patients with diabetic macular edema vs. those without macular edema, irrespective of their retinopathy severity. Comparisons were made using analysis of covariance to adjust for the systemic indicators HbA1c, Total Cholesterol, and duration of diabetes. Results: The levels of RANTES and MCP1 were significantly (p<.01) elevated in the patients with ischemic diabetic retinopathy compared to those with little or no ischemic retinopathy. The levels of ICAM were significantly (p<.01) depressed in the patient group with ischemic diabetic retinopathy. There were no significant differences between macular edema groups. Conclusions: A number of serum chemokines and adhesion molecules were found at significantly different levels in patients with more ischemic forms of diabetic retinopathy vs. those with less ischemic forms of diabetic retinopathy. These findings provide possible factors to identify at risk groups within the diabetic retinopathy patient population. These data may also further assess the possible pathogenesis of and identify potential anti-inflammatory therapies for ischemic diabetic retinopathy.
Keywords: cytokines/chemokines • diabetic retinopathy • clinical laboratory testing