Synergistic neuroprotective effects of the ROCK inhibitor Y27632 and atorvastatin in optineurin-E50K-mutant mice through inhibition of scleral fibroblast transdifferentiation.

Abstract

Normal-tension glaucoma (NTG) is a vision-threatening disorder whose pathogenesis remains incompletely understood. This study aimed to investigate the protective effects and molecular mechanisms of combined rho-associated protein kinase (ROCK) inhibitor and statin therapy on scleral fibroblast transdifferentiation in NTG, with the goal of providing novel therapeutic strategies and experimental evidence for glaucoma neuroprotection. In vitro experiments utilized a TGF-β1-induced scleral fibroblast transdifferentiation model, with drug effects evaluated through collagen gel contraction, scratch assays, immunofluorescence, qRT‒PCR, and western blotting. Synergistic drug concentrations were determined using CCK-8 and Synergy Finder analyses. In vivo, optineurin (OPTN)-E50K mutant mice were used as an NTG model, with treatment effects assessed by light‒dark shuttle tests, optomotor response tests, and HE staining. Molecular analyses included immunofluorescence, qRT‒PCR, and western blotting to evaluate scleral fibroblast transdifferentiation and ROCK1 expression. Our study demonstrated that scleral fibrosis is a pivotal pathological process in the retina degeneration of OPTN (E50K) mutant mice. The combined use of the ROCK inhibitor Y27632 and atorvastatin synergistically reduced the expression of fibrotic markers such as α-SMA and collagen I (dual inhibition of ROCK1 activity) and inhibited the transdifferentiation of scleral fibroblasts into myofibroblasts in OPTN(E50K) mutant mice. The combination therapy further improved retinal structure and visual function, as evidenced by increased retinal ganglion cell layer thickness and enhanced performance in light‒dark transition and optomotor response tests after alleviating scleral fibrosis. Taken together, the results of this study highlight the therapeutic potential of targeting scleral remodeling and neuroprotection in NTG via ROCK-statin combination therapy.