The effect of cilostazol on expression of thrombospondin-1 in diabetic retinopathy

To explore the effect of cilostazol in the pathophysiology of diabetic retinopathy and its mechanism, we intraperitoneal injection streptozotocin (STZ) to induce rats diabetic model to study the alteration of the thrombospondin-1 (TSP-1) in the retina of diabetic rats, cilostazol treatment diabetic rats and normal rats by immunohistochemistry, real-time quantitative reverse transcription-polymerase chain reaction. The weight, blood sugar and urine sugar were also measured before and after model induction of these three groups. The data of weight, blood sugar and urine sugar indicated no significant difference in these three groups before diabetes induction. Four weeks after the injection of STZ, the weight, blood sugar and urine sugar had significant difference among these three groups (P < 0.01). When compared with the normal retina, TSP-1 expression was increased in the diabetic rat's retina, as shown by increased optical density and immunohistochemistry positive cell number but this was not serious in cilostazol treatment rats (P < 0.01). Our study confirmed that up-regulation of TSP-1 expression in retina of streptozotocin-induced diabetic rats under hyperglycemia condition and cilostazol treatment could prevent TSP-1 overexpression. This indicates a protective way in the pathophysiology of diabetic retinopathy.