Clinical detection of precataractous lens protein changes using dynamic light scattering.

Abstract

OBJECTIVE:

To use dynamic light scattering to clinically assess early precataractous lens protein changes.

METHODS:

We performed a cross-sectional study in 380 eyes of 235 patients aged 7 to 86 years with Age-Related Eye Disease Study clinical nuclear lens opacity grades 0 to 3.8. A dynamic light-scattering device was used to assess alpha-crystallin, a molecular chaperone protein shown to bind other damaged lens proteins, preventing their aggregation. The outcome measure was the alpha-crystallin index, a measure of unbound alpha-crystallin in each lens. The association of the alpha-crystallin index with increasing nuclear opacity and aging was determined.

RESULTS:

There was a significant decrease in the alpha-crystallin index associated with increasing nuclear lens opacity grades (P < .001). There were significant losses of alpha-crystallin even in clinically clear lenses associated with aging (P < .001). The standard error of measurement was 3%.

CONCLUSIONS:

Dynamic light scattering clinically detects alpha-crystallin protein loss even in clinically clear lenses. alpha-Crystallin index measurements may be useful in identifying patients at high risk for cataracts and as an outcome variable in clinical lens studies.

CLINICAL RELEVANCE:

The alpha-crystallin index may be a useful measure of the protective alpha-crystallin molecular chaperone reserve present in a lens, analogous to creatinine clearance in estimating renal function reserve.

• Authors: Manuel B Datiles 3rd, Rafat R Ansari, Kwang I Suh, Susan Vitale, George F Reed, J Samuel Zigler Jr, Frederick L Ferris 3rd
• Journal: Archives of ophthalmology (Chicago, Ill. : 1960) (Arch Ophthalmol) Vol. 126 Issue 12 Pg. 1687-93 (Dec 2008) ISSN: 1538-3601 [Electronic] United States
• PMID: 19064850 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• alpha-Crystallins

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Aging (pathology)
• Animals
• Cataract (classification, diagnosis)
• Cattle
• Child
• Cross-Sectional Studies
• Humans
• Lens, Crystalline (chemistry)
• Light
• Middle Aged
• Prospective Studies
• Scattering, Radiation
• alpha-Crystallins (analysis)