Serum and Vitreous Levels of Visfatin in Patients with Diabetic Retinopathy

BACKGROUND Angiogenesis plays an important role in the mechanism of diabetic retinopathy (DR). Visfatin, a recently identified adipokine, is thought to possess an angiogenic effect. The aim of our study was to investigate serum and vitreous levels of visfatin in patients with proliferative diabetic retinopathy (PDR) and non-PDR (NPDR). MATERIAL AND METHODS A total of 280 diabetic patients (124 without DR, 56 with NPDR, and 100 with PDR) and 78 control subjects were enrolled in this study. Serum and vitreous levels of visfatin were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS Serum and vitreous visfatin levels in PDR patients were significantly elevated compared with those in the other 3 groups. NPDR patients showed elevated vitreous visfatin levels compared with patients without DR. However, no significant differences in serum visfatin levels were found between NPDR patients and patients without DR. In addition, control subjects had significantly lower levels of serum and vitreous visfatin compared with diabetic patients without DR, NPDR patients, and PDR patients. CONCLUSIONS Serum and vitreous visfatin levels are associated with the presence and severity of DR.