Methylation Profile of miR-9-1 and miR-9-1/-9-3 as Potential Biomarkers of Diabetic Retinopathy.

Aims: Analysis of the relationship between the methylation profile of miR-9-1 or miRs -9-1 / -9-3 and diabetic retinopathy.

Background: Diabetic Retinopathy (DR) is a frequent complication of Diabetes mellitus and it has a decisive impact on the quality of life, as it is one of the biggest causes of blindness in the adult population. Levels of microRNA-9 have been shown to be related to diabetes but little is known about its involvement with DR in humans.

Objective: To analyze the relationship between the methylation profile of miR-9-1 or miRs -9-1/-9-3 and DR.

Methods: 103 patients diagnosed with diabetes for 5 to 10 years were analyzed. The data were categorized according to clinical, biochemical, lifestyle and anthropometric parameters. DNA extracted from leukocyte samples was used to determine the methylation profile of miRs-9-1 and -9-3 using a specific methylation PCR assay.

Results: miR-9-1 methylation was related to diabetic retinopathy, indicating that methylation of this miR increases the chances of presenting retinopathy up to 5 times. In our analyses, diabetics with lower levels of creatinine and CRP showed significant reductions (99% and 97%) in presenting DR. Methylation of both miRs-9-1 and 9-3 methylated increases the chances of presenting DR by 8 times; in addition, a sedentary lifestyle can increase the risk for the same complication by up to 6 times.

Conclusion: Our results suggest that both methylation of miR-9-1 and e miRs-9-1 / 9-3 favors DR in patients with diabetes in a period of 5 to 10 years of diagnosis.