Background/Aims: Vildagliptin is an oral inhibitor of dipeptidyl peptidase-4, an enzyme mainly responsible for inactivating incretins, and one of the widely used drugs for the treatment of type 2 diabetes. However, effects of vildagliptin on retinal injury in diabetes remain unclear. We examined here whether oral administration of vildagliptin inhibited gene expression of inflammatory and thrombogenic parameters in Otsuka Long-Evans Tokushima Fatty rats (OLETF rats), an animal model of obese type 2 diabetes. Methods: OLETF rats at 22 weeks of age were given vehicle or 3 mg/kg of vildagliptin for another 10 weeks. Gene expression was analyzed in quantitative real-time reverse transcription-polymerase chain reaction. Results: Vildagliptin significantly inhibited the increase in body weight and decreased average fasting blood glucose in the OLETF rats. Compared with 22-week-old OLETF rats, gene expression levels of vascular endothelial growth factor, intercellular adhesion molecule-1, plasminogen activator inhibitor-1 and pigment epithelium-derived factor were significantly increased in the retinas of OLETF rats at 32 weeks of age, all of which were inhibited by treatment with vildagliptin. Conclusions: The present study demonstrated for the first time that vildagliptin inhibited inflammatory and thrombogenic reactions in the retinas of obese type 2 diabetic rats. Vildagliptin may play a protective role against diabetic retinopathy.

Keywords:
Vildagliptin, Intercellular adhesion molecule-1, Vascular endothelial growth factor, Diabetic retinopathy, Advanced glycation end product
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© 2013 S. Karger AG, Basel
2013
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