Modification of crystalline lens' structural proteins leads to cataract formation

May 2, 2005

Proteins appear to unfold in the crystalline lens and result in the accumulation of old protein in the nucleus and in the inner cortex, creating damage and leading to a cataract, explained John J. Harding, MD, who spoke during the "Ocular Pathology&#8212Beyond the Eye" symposium at the Association for Research in Vision and Ophthalmology annual meeting.

May 2 - Fort Lauderdale, FL - Proteins appear to unfold in the crystalline lens and result in the accumulation of old protein in the nucleus and in the inner cortex, creating damage and leading to a cataract, explained John J. Harding, MD, who spoke during the "Ocular Pathology-Beyond the Eye" symposium at the Association for Research in Vision and Ophthalmology annual meeting.

Chemical changes to the protein, such as glycation and carbamylation, can be responsible for the unfolding. "The modifications are related to known risk factors for cataract, such as diabetes, renal failure, and severe diarrhea," said Dr. Harding, of the Nuffield Laboratory of Ophthalmology, University of Oxford, England.

In addition, he has found that these modifications associated with cataract formation can inactivate a number of enzymes. In some cases, aspirin and non-steroid anti-inflammatory agents can be protective against glycation, he said.

"There are common pathways in human cataract, and there may be common aspects of the etiologies of a number of apparently different late-life diseases," Dr. Harding said.