Cilostazol protects against changes caused by streptozotocin-induced diabetic retinopathy

ABSTRACT Purpose: This study investigates the protective effect of cilostazol on the development and evolution of diabetic retinopathy in rats. Methods: Sixty male rats were divided into four groups: untreated nondiabetic rats, untreated diabetic rats, cilostazol-treated nondiabetic rats, and cilostazol-treated diabetic rats. The thickness of the internal limiting membrane to the outer limiting membrane, inner plexiform layer, inner nuclear layer, and outer nuclear layer were measured. The number of cell nuclei per 50-μm length in retinal sections was counted to quantify the degree of retinal cell loss. Results: The number of nuclei in the ganglion cell layer was significantly higher in untreated nondiabetic rats (p<0.05). The mean number of nuclei in the cilostazol-treated nondiabetic rats was significantly higher than that in the cilostazol-treated diabetic rats (p<0.05). The cilostazol-treated nondiabetic rats had a significantly higher mean nuclei count in the inner nuclear layer and inner plexiform layer as compared with the other groups (p<0.05). The total mean retinal thickness of the cilostazol-treated nondiabetic rats was significantly higher than that of cilostazol-treated diabetic rats and untreated diabetic rats (p<0.05). Conclusion: By decreasing the loss of ganglion cells and reducing the sensorineural atrophy in the internal retinal layers, cilostazol had a protective effect against changes caused by diabetic retinopathy in diabetic rats.