Analysis of N6-methyladenosine-modified mRNAs in diabetic cataract

World J Diabetes. 2023 Jul 15;14(7):1077-1090. doi: 10.4239/wjd.v14.i7.1077.

Abstract

Background: Cataracts remain a prime reason for visual disturbance and blindness all over the world, despite the capacity for successful surgical replacement with artificial lenses. Diabetic cataract (DC), a metabolic complication, usually occurs at an earlier age and progresses faster than age-related cataracts. Evidence has linked N6-methyladenosine (m6A) to DC progression. However, there exists a lack of understanding regarding RNA m6A modifications and the role of m6A in DC pathogenesis.

Aim: To elucidate the role played by altered m6A and differentially expressed mRNAs (DEmRNAs) in DC.

Methods: Anterior lens capsules were collected from the control subjects and patients with DC. M6A epitranscriptomic microarray was performed to investigate the altered m6A modifications and determine the DEmRNAs. Through Gene Ontology and pathway enrichment (Kyoto Encyclopedia of Genes and Genomes) analyses, the potential role played by dysregulated m6A modification was predicted. Real-time polymerase chain reaction was further carried out to identify the dysregulated expression of RNA methyltransferases, demethylases, and readers.

Results: Increased m6A abundance levels were found in the total mRNA of DC samples. Bioinformatics analysis predicted that ferroptosis pathways could be associated with m6A-modified mRNAs. The levels of five methylation-related genes-RBM15, WTAP, ALKBH5, FTO, and YTHDF1-were upregulated in DC samples. Upregulation of RBM15 expression was verified in SRA01/04 cells with high-glucose medium and in samples from DC patients.

Conclusion: M6a mRNA modifications may be involved in DC progression via the ferroptosis pathway, rendering novel insights into therapeutic strategies for DC.

Keywords: Diabetic cataract; Epitranscriptomic microarray; Ferroptosis; N6-methyladenosine; RNA.