Related Experiment Video
Updated: May 22, 2026
05:56
Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model
Published on: April 3, 2016
Impaired P4HA1-Driven Hydroxyproline Formation Mediates Scleral Collagen Disruption in Form-Deprivation Myopia
Jing Li1, Jiaojiao Feng2, Yibo Han1
1Ophthalmology &Optometry Medical School, Shandong University of Traditional Chinese Medicine, Jinan, China.
Investigative Ophthalmology & Visual Science
|May 21, 2026
Summary
Impaired proline hydroxylation in myopia (FDM) leads to hydroxyproline deficiency and collagen issues. Restoring P4HA1 expression in the sclera corrects these defects, reducing myopia progression.
Area of Science:
- Ophthalmology
- Biochemistry
- Extracellular Matrix Biology
Background:
- Scleral extracellular matrix (ECM) remodeling is key in myopia progression.
- Metabolic drivers of ECM remodeling in myopia are not well understood.
Purpose of the Study:
- Investigate if impaired arginine-proline metabolism, specifically P4HA1-mediated proline hydroxylation, causes hydroxyproline deficiency in myopia.
- Determine if this deficiency leads to collagen disorganization and axial elongation in form-deprivation myopia (FDM).
Main Methods:
- Induced monocular FDM in guinea pigs for two weeks.
- Assessed refractive error, axial length, scleral morphology, and collagen ultrastructure.
- Utilized metabolomics and AAV8-P4HA1 gene delivery to test rescue effects; used 1,4-DPCA to inhibit P4HA in fibroblasts.
Main Results:
- FDM caused myopic shift, axial elongation, scleral thinning, and ECM disorganization.
- Metabolomics showed altered arginine-proline metabolism with reduced hydroxyproline and decreased P4HA1/P4HA3 expression.
- P4HA1 overexpression normalized hydroxyproline, improved collagen structure, and reduced axial elongation.
Conclusions:
- Reduced scleral P4HA1 expression in FDM eyes correlates with hydroxyproline deficiency and collagen disorganization.
- Restoring scleral P4HA1 inhibits excessive axial elongation, suggesting the P4HA1-hydroxyproline axis is a potential myopia control target.
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