Corneal Sensory Denervation Causes Epithelial Ferroptosis and Delayed Healing in Mice.

Abstract

Purpose: This study aimed to elucidate the role and mechanism of corneal nerves in regulating epithelial cell response against ferroptosis.

Methods: Denervated mouse models were established via surgical axotomy and capsaicin treatment. Monochlorobimane staining was employed to detect cellular glutathione (GSH) levels in the corneal epithelium, and real-time quantitative PCR and immunofluorescence staining were used to evaluate GSH-related gene expression in denervated models and corneas of patients with neurotrophic keratitis. Scanning electron microscopy was utilized to observe mitochondrial morphology in corneal epithelial cells. Ferroptosis inhibitor ferrostatin-1 was administered post-corneal scrape in capsaicin-treated mice, followed by transcriptomic sequencing. The p53 agonist Kevetrin activated p53 in scraped corneas and cultured corneal epithelial cells. Furthermore, capsaicin was topically applied to Trp53+/- mice, followed by corneal epithelial scraping.

Results: In denervated models, the expression of GSH-related genes was downregulated, and mitochondrial morphology exhibited characteristics of ferroptosis in corneal epithelial cells. The delay in corneal wound healing induced by TRPV1+ sensory denervation was ameliorated by ferrostatin-1 treatment. RNA sequencing and immunofluorescence staining demonstrated upregulated p53 in TRPV1-denervated mice, which was subsequently downregulated following ferrostatin-1 treatment. Kevetrin exacerbated wound healing delays, whereas Trp53+/- mice exhibited accelerated healing post-capsaicin denervation compared to wild-type controls.

Conclusions: TRPV1+ sensory nerves play a regulatory role in preventing ferroptosis of corneal epithelial cells through the p53/AKT/mTOR signaling pathway. Targeting this pathway may offer therapeutic potential for neurotrophic keratopathy and related disorders.