Purpose: Diabetic retinopathy (DR) is the leading cause of blindness among working age adults. Circular RNAs (circRNAs) are a kind of noncoding RNAs that are involved in the development of some diseases. Here, we aimed to determine the possible role of circRNAs in the pathogenesis of DR by determining the expression profile of circRNAs in the serum of DR patients. Methods: Nineteen subjects with type 2 diabetes mellitus with proliferative DR (T2DR), 15 subjects with type 2 diabetes mellitus without DR (T2DM), and 21 age-matched nondiabetic control subjects were included in the study. Expression profiles in the serum samples from 5 subjects of each group were studied by circular microarray and validated by quantitative real-time polymerase chain re- action (qRT-PCR) in another 40 subjects. Bioinformatic software was used to predict the microRNA response elements. Results: Thirty circRNAs were significantly upregulated in the serum of T2DR patients compared with the serum from both T2DM and control patients. Further, the altered expression of 7 circRNAs (hsa_circRNA_063981, hsa_circRNA_ 404457, hsa_circRNA_100750, hsa_circRNA_406918, hsa_ circRNA_104387, hsa_circRNA_103410, and hsa_circRNA_ 100192) were verified by qRT-PCR. Conclusion: This study suggested a potential role of circRNAs in the pathogenesis of DR and provides novel molecular targets for clinical therapy.

Keywords:
Circular RNA, Diabetic retinopathy, Microarray
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