The aim of the study was to determine aqueous humor and serum levels of brain-derived neurotrophic factor (BDNF) in diabetic patients with and without retinopathy.
The study included diabetic patients with or without retinopathy, who had an indication for cataract surgery. The study groups were diabetic patients without retinopathy (Group 2), with nonproliferative diabetic retinopathy (Group 3), and with proliferative retinopathy (Group 4). To quantitatively determine the amount of BDNF in samples, the RayBio Human BDNF ELISA kit (Norcross, GA), based on an enzyme-labeled immunosorbent assay was used.
The median serum BDNF levels were significantly lower in all the study groups than in the control group (P values: 0.038 Group 2, 0.02 Group 3, and 0.002 Group 4). Serum BDNF was lower in Group 4 than in Group 3 (P = 0.030), and in Group 3 than in Group 2 (P = 0.04). The median aqueous humor BDNF levels were significantly decreased in all groups (P values: 0.047 Group 2, 0.021 Group 3, and 0.007 Group 4). There was no significant difference between Groups 2, 3, and 4 (P = 0.214).
The serum and aqueous humor BDNF levels decreased in patients with diabetes mellitus (DM) before the emergence of clinical signs of retinopathy.
We evaluated serum and aqueous humor levels of brain-derived neurotrophic factor in diabetic patients with and without retinopathy. The serum and aqueous humor brain-derived neurotrophic factor levels decreased in patients with DM before the emergence of clinical signs of retinopathy.
*Department of Ophthalmology, Afyonkarahisar Sandıklı State Hospital, Afyonkarahisar, Turkey;
†Department of Ophthalmology, Atatürk Education and Research Hospital, Yıldırım Beyazıt University, Ankara, Turkey;
‡Department of Microbiology, Hacettepe University, Ankara, Turkey; and
§Department of Immunology, Çukurova University, Adana, Turkey.
Reprint requests: Ayşe Güzin Taşlipinar Uzel, MD, Afyonkarahisar Sandıklı State Hospital, Department of Ophthalmology, 03510, Sandıklı/Afyonkarahisar, Turkey; e-mail: email@example.com
Financial support was provided by Yıldırım Beyazıt University Scientific Research Project. The sponsor had no role in the design or conduct of this research.
None of the authors has any conflicting interests to disclose.