Transcriptomic Analysis in a Model of Aniridia-Associated Keratopathy for Target Discovery and Evaluation of Duloxetine Therapy

Purpose: Aniridia-associated keratopathy (AAK) leads to loss of corneal transparency because of epithelial, inflammatory, and pathological vascular changes. Here, we sought to understand this process at the transcriptomic level while evaluating an experimental pharmacotherapy for potential modulatory effects. Method: 17 Pax6+/- Small-eye (Sey) heterozygous mice with p.Gly208* Pax6 mutation and 10 wild-type 129S1/SvImJ mice at four months of age were examined to identify dysregulated genes and pathways in established AAK. We next evaluated the potential efficacy of 10 µM duloxetine administered as eye drops twice daily for 90 days, assessing outcomes at the transcriptomic level via microarray and protein level with Western blot and immunostaining. Results: Transcriptomic analysis of the cornea revealed enrichment of Ccl21 gene family members associated with lymphangiogenesis, along with upregulation of genes involved in inflammation, cell adhesion, differentiation, motility, and keratinization, and downregulation of drug metabolism with significantly dysregulated genes emerging as potential therapeutic targets, including Gpha2, Chrnb3, Epgn, Cnfn, kallikreins and inflammation mediators Il18r1 and classical complement factors. Duloxetine therapy failed to regress AAK in adult corneas; however, transcriptomic profiling indicated duloxetine suppressed inflammatory genes and promoted anti-inflammatory and protective activity while modulating drug metabolism, suggesting potential beneficial effects in the cornea. Conclusions: Transcriptomics reveals multiple unexplored pathways and genes altered in the AAK mouse model. Although clinical results with duloxetine are promising, our current regimen and delivery method did not improve established disease. Duloxetine's therapeutic potential requires further study.