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Published on: May 15, 2019
Decreased vitreal hyaluronan levels with aging.
Hirotaka Itakura1, Shoji Kishi, Nobuo Kotajima
1Department of Ophthalmology, Gunma University School of Medicine, Maebashi, Japan.
Summary
Vitreous hyaluronan levels decrease with age in human eyes. After vitrectomy surgery, hyaluronan levels in the eye are significantly lower, suggesting it is not produced post-surgery.
Area of Science:
- Ophthalmology
- Biochemistry
- Gerontology
Background:
- Hyaluronan is a key component of the vitreous humor.
- Age-related changes in vitreous composition are not fully understood.
Purpose of the Study:
- To examine age-related changes in human vitreous hyaluronan levels.
- To assess hyaluronan levels before and after vitrectomy.
Main Methods:
- Vitreous samples were collected during vitrectomy from patients with macular hole and diabetic retinopathy.
- Postoperative fluid samples were obtained via fluid-air exchange.
- Hyaluronan levels were quantified using a sandwich binding protein assay.
Main Results:
- Vitreous hyaluronan levels showed a significant inverse correlation with patient age.
- Postoperative hyaluronan levels were significantly lower than pre-operative levels in both macular hole and diabetic retinopathy groups.
Conclusions:
- Vitreous hyaluronan decreases significantly with aging.
- High-molecular-weight hyaluronan is not detected in post-vitrectomy vitreous fluid, indicating a lack of production after surgery.
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