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Updated: Jul 16, 2026
07:22
Using a Laminating Technique to Perform Confocal Microscopy of the Human Sclera
Published on: May 6, 2016
Proteoglycan composition in the human sclera during growth and aging
J A Rada1, V R Achen, S Penugonda
1Department of Anatomy and Cell Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks 58202-9037, USA. jarada@medicine.nodak.edu
Investigative Ophthalmology & Visual Science
|June 14, 2000
Summary
Human scleral proteoglycans change with age. Aggrecan increases while biglycan and decorin decrease, impacting scleral biomechanics.
Area of Science:
- Ocular biology
- Biochemistry
- Extracellular matrix research
Background:
- Proteoglycans are crucial components of the extracellular matrix.
- Scleral proteoglycans play a role in maintaining ocular structure and function.
- Understanding age-related changes in scleral composition is vital for eye health.
Purpose of the Study:
- To characterize human scleral proteoglycans across a wide age range.
- To identify age-related alterations in the synthesis and accumulation of scleral proteoglycans.
- To correlate proteoglycan changes with potential shifts in scleral biomechanical properties.
Main Methods:
- Human donor eyes (2 months to 94 years) were analyzed.
- Proteoglycans were extracted and separated using guanidine hydrochloride and Sepharose CL-4B chromatography.
- Composition was further analyzed by anion-exchange chromatography, SDS-PAGE, and Western blotting.
Main Results:
- Three major proteoglycan peaks were identified: aggrecan (two forms) and small proteoglycans (biglycan, decorin).
- Aggrecan synthesis and accumulation increased with age, particularly in the posterior sclera.
- Biglycan and decorin levels initially rose then significantly decreased with advanced age.
Conclusions:
- Scleral proteoglycan composition undergoes significant age-related changes.
- These alterations in aggrecan, biglycan, and decorin likely influence scleral biomechanical properties.
- Findings contribute to understanding ocular aging and structural integrity.
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