Dataset Information

Age-related changes in eye lens biomechanics, morphology, refractive index and transparency.

ABSTRACT: Life-long eye lens function requires an appropriate gradient refractive index, biomechanical integrity and transparency. We conducted an extensive study of wild-type mouse lenses 1-30 months of age to define common age-related changes. Biomechanical testing and morphometrics revealed an increase in lens volume and stiffness with age. Lens capsule thickness and peripheral fiber cell widths increased between 2 to 4 months of age but not further, and thus, cannot account for significant age-dependent increases in lens stiffness after 4 months. In lenses from mice older than 12 months, we routinely observed cataracts due to changes in cell structure, with anterior cataracts due to incomplete suture closure and a cortical ring cataract corresponding to a zone of compaction in cortical lens fiber cells. Refractive index measurements showed a rapid growth in peak refractive index between 1 to 6 months of age, and the area of highest refractive index is correlated with increases in lens nucleus size with age. These data provide a comprehensive overview of age-related changes in murine lenses, including lens size, stiffness, nuclear fraction, refractive index, transparency, capsule thickness and cell structure. Our results suggest similarities between murine and primate lenses and provide a baseline for future lens aging studies.

SUBMITTER: Cheng C

PROVIDER: S-EPMC6949082 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Age-related changes in eye lens biomechanics, morphology, refractive index and transparency.

Cheng Catherine C Parreno Justin J Nowak Roberta B RB Biswas Sondip K SK Wang Kehao K Hoshino Masato M Uesugi Kentaro K Yagi Naoto N Moncaster Juliet A JA Lo Woo-Kuen WK Pierscionek Barbara B Fowler Velia M VM

Aging 20191216 24

Life-long eye lens function requires an appropriate gradient refractive index, biomechanical integrity and transparency. We conducted an extensive study of wild-type mouse lenses 1-30 months of age to define common age-related changes. Biomechanical testing and morphometrics revealed an increase in lens volume and stiffness with age. Lens capsule thickness and peripheral fiber cell widths increased between 2 to 4 months of age but not further, and thus, cannot account for significant age-depende ...[more]

PMID: 31844034

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Dataset Information

Age-related changes in eye lens biomechanics, morphology, refractive index and transparency.

Publications

Age-related changes in eye lens biomechanics, morphology, refractive index and transparency.

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