PFKFB3 functions as a metabolic checkpoint in corneal fibrosis by coordinating glycolytic reprogramming, fibrotic activation, and inflammation

Aims: Corneal fibrosis is a leading cause of blindness with limited treatment options. This study explores the role of PFKFB3-driven glycolytic reprogramming in the development of corneal fibrosis and evaluates its potential as a therapeutic target.

Materials and methods: An alkali burn-induced corneal injury model was established in C57BL/6 mice to investigate temporal changes in glycolysis during wound healing. Pathological alterations were assessed using slit-lamp microscopy, hematoxylin and eosin (H&E) staining, proteomic analysis, and Western blotting. Glycolytic flux was measured by determining the extracellular acidification rate (ECAR) in both injured corneas and cultured keratocytes stimulated with TGF-β1 or LPS. Further mechanistic studies were conducted to elucidate the specific role of PFKFB3 in corneal repair.

Key findings: Proteomic analysis revealed a significant enrichment of glycolytic pathways during corneal repair. Following alkali injury, murine corneas exhibited a time-dependent increase in glycolytic activity, peaking at day 14, coinciding with the fibrotic phase of wound healing. Pharmacological inhibition of PFKFB3 in vivo produced multiple therapeutic benefits, including accelerated wound closure, reduced corneal opacity, and suppressed myofibroblast differentiation. This intervention also decreased the ECAR and reduced the production of fibrotic extracellular matrix components. Complementary in vitro studies confirmed that PFKFB3 blockade effectively mitigated both TGF-β1-induced fibrotic transformation and LPS-mediated inflammatory activation in keratocytes.

Significance: In conclusion, our study identifies PFKFB3-driven glycolytic reprogramming as a critical metabolic checkpoint in corneal fibrosis. Targeting this node pathway attenuates both myofibroblast transformation and inflammatory responses.