To investigate aqueous humor (AH) and serum levels of brain-derived neurotrophic factor (BDNF) in non-proliferative diabetic retinopathy (NPDR) patients with diabetic macular edema (DME).
Methods:
The prospective study consists of 20 patients with DME NPDR, 20 patients with no-DME NPDR, and 20 healthy control subjects. Serum and AH samples were obtained during cataract surgery and intravitreal injection. Serum and AH levels of BDNF were measured by enzyme-linked immunosorbent assay.
Results:
The mean serum levels of BDNF were lower in both NPDR groups compared to the control group (DME NPDR group, p = 0.015; no-DME NPDR group, p = 0.024). Furthermore, the mean serum level of BDNF was lower in the DME NPDR group compared to the no-DME NPDR group (p = 0.041). The mean AH levels of BDNF were significantly reduced in both NPDR groups compared to the control group (DME NPDR group, p < 0.001; no-DME NPDR group, p = 0.006). Further, the mean AH level of BDNF was significantly lower in the DME NPDR group compared to the no-DME NPDR group (p = 0.037).
Conclusion:
Serum and AH levels of BDNF were reduced in NPDR patients with DME than without DME.
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