AIM: To identify the oxidative stress related miRNA in retinal pigment epithelium(RPE)by miRNA expression profile chip and provide a new idea for comprehensive and deep research on the molecular mechanisms of age-related macular degeneration(AMD).

METHODS: Human RPE cell line D407 was treated by 100, 200, 400μmol/L H₂O₂ for 24h and harvested to isolate total RNA by Trizol reagent. The expression difference of D407 cell miRNA after processing of different concentrations was generated by Exiqon miRCURY LNA^TM microRNA expression profile chip and the changes after processing of different concentrations were conducted by Hierarchical Clustering analysis. The results of chips were verified through Stem loop realtime PCR, and the target genes of identified miRNAs were predicted by bioinformatics software.

RESULTS: Among the 1 425 known miRNAs listed on microarray, 367 miRNAs showed differential expression after H₂O₂ treatment. The Treeview Clustering showed that 17 miRNAs, including miR-31, were downregulated along with the increase of H₂O₂ concentration. Meanwhile, 7 miRNAs, including miR206, were upregulated. The results of qRT-PCR further validated the better results of microarray.

CONCLUSION:The miRNA expression of human RPE is dramatically changed after H₂O₂ treatment. miRNA adjusts the molecules level of micrornas transcription and it is involved in cell oxidative stress reaction, and miRNA may play a pivotal role in the pathogenesis and development of AMD.