Author: Supraja Sridhar
Department: Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, USA
Abstract
Although cataracts are the most prevalent cause of blindness in the world, the only effective treatment currently available is surgical lens replacement, an invasive and expensive procedure1. The probability of developing cataracts is a function of increasing age. Thus, as an increased proportion of people live longer, the need for a less invasive, more accessible treatment, including prevention, becomes more important. Understanding the mechanism of cataract formation through the use of basic research approaches can potentially lead to alternative treatment. The ICR/f rat in this investigation is a spontaneous, hereditary model of cataract disease and is one of the few effective animal models available for the study of senile cataractogenesis. Because of mutations in chromosomes 8 and 15, all ICR/f rats will develop cataracts at approximately 75 to 80 days of age1.
The goal of this study is to examine changes that occur in the proteins in the eye lens of these rats with aging. The hypothesis is that changes in the solubility of lens proteins occur with aging and these alterations are associated with the process of cataract development.The soluble protein in the lens ocular tissue collected from ICR/f rats of varying ages were analyzed by SDS-PAGE gels in order to characterize them by molecular weight. A method was developed to study the remaining insoluble lens protein fraction in conjunction with the soluble extractions.
The results from thisinvestigation suggest that the once soluble lens proteins appear to become insoluble during the aging process. As the proteins precipitate out of solution in the lens, 2the refractive index decreases and the lens becomes opaque, the characteristic feature of cataracts. This method provides biochemical information about cataract development and can be used to evaluate the efficacy of potential cataract treatments.
References
- Floyd, K. Distribution/Localization and relative quantitation of terminal αA-crystallin truncation products within lenses of ICR/F rats treated with dietary supplemented genistein. MSPH Thesis, University of Alabama at Birmingham (2012).
Download the full article (PDF): Eye Lens Protein Composition in Aging Cataractous ICR/f Rats