Plasma E-selectin levels can play a role in the development of diabetic retinopathy.

PURPOSE: Diabetic retinopathy is one of the leading causes of blindness. There are several risk factors, such as the duration of diabetes or glycemic control of the patient; however, several biochemical factors also alter the process. Our aim was to investigate the role of soluble E-selectin in the formation of diabetic retinopathy. PATIENTS AND METHODS: Fifty-seven patients (37 female and 20 male, aged 61.71 ± 12.31 years) and 14 healthy control subjects (ten female and four male, aged 63.06 ± 10.46 years) were enrolled in the study. We measured the soluble E-selectin level in the plasma of patients by ELISA. All patients underwent careful ophthalmological examination, including ophthalmoscopy and color fundus photography, while diabetic retinopathy grading was performed in line with the 2012 classification of the American Academy of Ophthalmology (AAO). RESULTS: The soluble E-selectin level was significantly higher in patients with diabetes compared to controls (32.95 ng/ml vs. 26.55 ng/ml, p = 0.03). Dividing patients into groups by the presence of retinopathy, the E-selectin level was also significantly higher in the retinopathy group (p < 0.05). When we examined diabetic patients by the severity of retinopathy (groups A, B, and C, by the guidelines of the AAO), however, we did not find any significant difference in soluble E-selectin levels, although it tended to be higher in group B. CONCLUSIONS: An elevated E-selectin level can play a role in the development of diabetic retinopathy, but it does not seem to alter disease severity. However, glycemic control and the reduction of cardiovascular risk factors may also alter the level of E-selectin that might play a role in the prevention of diabetic retinopathy.

Vascular endothelial growth factor levels in tears of patients with retinal vein occlusion.

PURPOSE: We measured vascular endothelial growth factor (VEGF) levels in tear fluid and serum in patients with retinal vein occlusion (RVO). PATIENTS AND METHODS: Eight patients with RVO due to secondary macular oedema were examined. VEGF levels were measured by enzyme-linked immunosorbent assay. All patients had a full ophthalmic examination (visual acuity, slit lamp biomicroscopy, perimetry, and fluorescein angiography). Central retinal thickness (CRT) was examined using optical coherence tomography (OCT). Tear and serum samples were collected and examinations were performed at diagnosis and 1 and 4 weeks later. RESULTS: VEGF levels in the tears of RVO eyes were significantly higher than in fellow eyes at diagnosis and after both 1 and 4 weeks (paired t test, p1 = 0.01, p2 = 0.02, p3 = 0.006). We found a weak but significant positive correlation between VEGF levels in tear fluid and serum of patients with RVO (r = 0.21), while this correlation tended to be stronger between the fellow eyes and serum levels (r = 0.33). CONCLUSION: To the best of our knowledge, we are the first to report an increased level of VEGF in the tear fluid of patients with RVO. Alterations of VEGF levels in tears may be useful for determining stages of RVO. This non-invasive and objective method may also be helpful for estimating the severity of macular oedema and efficacy of treatment.