Role of neuroproteins in retinal neurodegeneration in diabetic retinopathy

Abstract

Aim. To evaluate the serum levels of S100b protein, brain-derived neurotrophic factor (BDNF), and nerve growth factor (NGF) in patients with type 2 diabetes mellitus, as well as to establish a correlation between the studied parameters and retinal neurodegeneration.Methods. In total, 80 patients with confirmed type 2 diabetes (experimental group) and 30 healthy volunteers (control group) were included in the study. All patients were examined using an RTVue-100 optic coherence tomography scanner (Optovue, USA) and a MAIA microperimeter (CenterVue, Italy). The serum levels of S100b, BDNF, and NGF were determined by a sandwich-type solid-phase enzyme immunoassay using reagents produced by R&D Diagnostics Inc. (USA).Results. The serum level of S100b protein was found to be significantly (p = 0.001) higher in the experimental group, comprising 56.86 (31,12–104,02) pg/ml, compared to that in the control group of 45.19 (37.27–51.79) pg/ml. Conversely, the brain-derived neurotrophic factor (BDNF) showed a significant (p = 0.02) decrease to the level of 27.38 (25.15–29.12) pg/ml in the experimental group compared to the level of 30.19 (27.38–32.14) pg/ml in the control group. The serum level of nerve growth factor (NGF) in the experimental group was found to be 7.53 (5.63–10.54) pg/ml, thereby exceeding significantly (p = 0.02) the level of 5.96 (4.77–8.13) pg/ml in the control group.Conclusions. The results obtained indicate an imbalance in the serum levels of the studied neuroproteins in patients with type 2 diabetes mellitus and retinal neurodegeneration signs. The identified variations require further research in order to determine the feasibility of their use as additional criteria for predicting the development of retinal neurodegeneration in such patients.