In Vitro Biochemical Approaches to Senile Cataract Formation

Abstract

Protein aggregation, impairment of electrolyte transport systems, protein oxidation, and so on, are known as biochemical changes in the human lens accompanying with the development of senile cataract. The report presented here demonstrates that calcium-induced lens protein aggregation is remarkably accelerated by oxidation (or photo-oxidation), and that electrolyte transport systems of cell membrane in the lens are easily damaged by oxidation. From the above results, a possible mechanism of senile cataract formation is proposed as follows; damage to lens cell membrane and denaturation of lens protein proceed during the cataract development by oxidative stress, and aggregation of denatured lens protein, leading to lens opacity, is induced by calcium ions increasing in the lens with the membrane damage.