I n t r o d u c t i o n: RANTES regulates leukocyte recruitment to areas affected by the inflammatory process. Microvesicles (MVs) belong to a subpopulation of extracellular vesicles and show proangiogenic potential by transferring bioactive molecules to target cells.

Obj e c t i v e s: The aim of this study was to determine the relationship between circulating proangiogenic factors (MVs and RANTES) and diabetes complications in patients with different severities of diabetic retinopathy (DR). CCR5 (CD195) receptors transported by annexin V-labeled MVs were also investigated. Patients and Methods: Diabetic patients (n = 61), among whom 35 had confirmed DR classified according to guidelines, and controls (n = 25) were included. MVs were isolated by centrifugation and analyzed using flow cytometry, RANTES was assessed by ELISA.

R e s u l t s: T h e study group diff ered from the control group with respect to BMI, age, heart rate and systolic blood pressure. Additionally, glucose and creatinine concentrations were signifi cantly increased: 5.30 [5.09–5.62] vs. 9.38 [7.48–11.55] (p<0.0001) mmol/l and 74.59 [64–84] vs. 89.00 [77.11–105.44] μmol/l (p = 0.0005), respectively. RANTES concentrations were significantly increased in diabetic patients compared to those of controls (15.5 (9.7–18.1) vs. 8.9 (0.9–14.6) μg/ml (p = 0.011)), and RANTES concentration significantly increased with respect to nonproliferative DR progression. Moreover, the number of CCR5-positive MVs was significantly increased in patients with heavy nonproliferative diabetic retinopathy (HNPDR) compared to those with soft nonproliferative DR (SNPDR): 1178 [836–2254] vs. 394 [275–799] counts/μl.

C o n c l u s i o n s: Correlation of RANTES concentrations with the stage of nonproliferative DR and the statistically significant dependence of CCR5-positive MVs with disease progression suggest that MVs and RANTES can be considered new biomarkers.

The prevalence of vitamin D deficiency in the American and European population is estimated to be extremely high. Although fewer people today suff er from serious health problems related to calcium and phosphate metabolism resulting from vitamin D deficiency, there are more and more studies suggesting that calcitriol may play an important role in the pathogenesis of other diseases in virtually every body system. A growing body of research shows that through its ubiquitously expressed receptor, calcitriol displays potent anti-angiogenic an anti-inflammatory activity. Th is review summarizes recent discoveries regarding these non-classical eff ects of vitamin D and their clinical implications. Data collection focused on the prevention and treatment of ocular diseases as well as on the underlying mechanisms.