| First Author | Murray AR | Year | 2013 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 54 |
| Issue | 3 | Pages | 1689-97 |
| PubMed ID | 23404117 | Mgi Jnum | J:214916 |
| Mgi Id | MGI:5604204 | Doi | 10.1167/iovs.12-10921 |
| Citation | Murray AR, et al. (2013) MicroRNA-200b downregulates oxidation resistance 1 (Oxr1) expression in the retina of type 1 diabetes model. Invest Ophthalmol Vis Sci 54(3):1689-97 |
| abstractText | PURPOSE: MicroRNAs (miRNAs) are known to participate in post-transcriptional regulation of gene expression and are involved in multiple pathogenic processes. Here, we identified miRNA expression changes in the retinas of Akita mice, a genetic model of type 1 diabetes, and investigated the potential role of miRNA in diabetic retinopathy. METHODS: Visual function of Akita and control mice was evaluated by electroretinography. MiRNA expression changes in the retinas of Akita mice were identified by miRNA-specific microarray and confirmed by quantitative RT-PCR (qRT-PCR). The potential downstream targets of identified miRNAs were predicted by bioinformatic analysis using web-based applications and confirmed by dual luciferase assay. The mRNA and protein changes of identified downstream targets were examined by qRT-PCR and Western blot analysis. RESULTS: MiRNA-specific microarray and qRT-PCR showed that miR-200b was upregulated significantly in the Akita mouse retina. Sequence analysis and luciferase assay identified oxidation resistance 1 (Oxr1) as a downstream target gene regulated by miR-200b. In a human Muller cell line, MIO-M1, transfection of a miR-200b mimic downregulated Oxr1 expression. Conversely, transfection of MIO-M1 with a miR-200b inhibitor resulted in upregulated Oxr1. Furthermore, overexpression of recombinant Oxr1 attenuated oxidative stress marker, nitration of cellular proteins, and ameliorated apoptosis induced by 4-hydroxynonenal (4-HNE), an oxidative stressor. Similarly, transfection of a miR-200b inhibitor decreased, whereas transfection of miR-200b mimic increased the number of apoptotic cells following 4-HNE treatment. CONCLUSIONS: These results suggested that miR-200b-regulated Oxr1 potentially has a protective role in diabetic retinopathy. |
