The Role of Micro RNA in Corneal Neovascularization and Its Relation to VEGF

The Role of MicroRNAs in Corneal Neovascularization and Its Relation to VEGF Objective: Our aim in this study was to investigate changes in vascular endothelial growth factor(VEGF) associated miRNA levels during corneal neovascularization(CNV); to elucidate the process of corneal neovascularization, to prepare the ground for future experimental, clinical studies and drug treatments. Method: Twelve Wistar-Albino male rats were randomly divided into two consecutive groups and two corneas of each rat were used. In all groups, CNV was formed with silver nitrate bars. At the end of the study, the rats were sacrificed by cervical dislocation under anesthesia with ether to remove the cornea. qRT-PCR Array and qRT-PCR methods were used to look at VEGF and miRNA expression levels in corneas. Data analysis was done using web array based on PCR Array data software (http://www.sabiosciences.com/pcrarraydataanalysis.php). Findings: When corneal specimens of control rats were compared between corneal neovascularized rats and VEGF levels quantitatively measured by qRT-PCR, statistically significant difference was observed between Fold-regulation value >2 (p <0.05). In the result of miRNA PCR Array under and over expression in both groups; statistically significant difference was found between nine genes Fold-regulation values <-2 and Fold-Regulation >2 (p <0.05). When corneals items of corneal neovascularized rats and control rats were compared, statistically significant over expression(Fold-regulation value >2) of mo-miR-21_2, mo-miR-126_1 and mo-miR-150_1 genes were detected (Respectively p = 0.002443, p = 0.030146, p = 0.000348). The identical comparison, a statistically significant under expression of Fold-regulation value <-2 mo-miR-184_1 gene was detected (p = 0.006428). In addition, in contast to two groups, the under expression of the mo-miR-31_1 (p = 0.005082) gene was found to be statistically significant close to Fold regulation value -2. Conclusion: At the end of the study, VEGF expression increased statistically in corneal neovascularization group in experimental burns; It has been observed that the mo-miR-21_2, mo-miR-126_1 and mo-miR-150_1 genes up regulate VEGF expression and the mo-miR-184_1 gene down regulates VEGF expression. Key words: Corneal neovascularization, vascular endothelial growth factor, microRNA, miRNA, co-polymerase chain reaction.