ANNALS EXPRESS: The association of serum and vitreous adropin concentrations with diabetic retinopathy.

OBJECTIVE: Adropin, a newly identified regulatory protein encoded by Enho gene, is correlated with insulin sensitivity and diabetes. The aim of this study is to determine whether serum and vitreous adropin concentrations are correlated with the presence of diabetic retinopathy (DR).

METHODS: A population of 165 patients with type 2 diabetes mellitus (T2DM) [52 without DR, 69 with non-proliferative diabetic retinopathy (NPDR), and 44 patients with proliferative diabetic retinopathy (PDR)] was enrolled in this study. The control group enrolled 68 healthy subjects who had underwent vitrectomy for retinal detachment. Serum and vitreous adropin concentrations were examined using enzyme-linked immunosorbent assay method.

RESULTS: Control subjects had significantly higher serum and vitreous adropin concentrations compared with diabetic patients. Serum and vitreous adropin concentrations in PDR patients were significantly reduced compared with those in NPDR patients and T2DM patients without DR. In addition, there were lower serum and vitreous adropin concentrations in NPDR patients compared with T2DM patients without DR. Logistic regression analysis revealed that serum and vitreous adropin were associated with a decreased risk of T2DM and DR.

CONCLUSION: Serum and vitreous adropin concentrations are negatively associated with the presence of DR. Key words: serum; vitreous; adropin; diabetic retinopathy; inflammation.