Aggregation and fibrillation of eye lens crystallins by homocysteinylation; implication in the eye pathological disorders.

There are several evidences, suggesting a relationship between hyperhomocysteinemia and various diseases of the visual system. Therefore in this study the effects of homocysteinylation on aggregation and fibrillation of lens crystallins were studied using spectroscopic techniques, SDS-PAGE and western blot analysis. The results of UV-Vis absorption studies suggest an induction of lens protein aggregation after homocysteinylation. Furthermore, the existence of fibril in the aggregate of lens proteins confirmed by Congo red absorption measurement and Thioflavin-T fluorescence assay. Taken together the results of SDS-PAGE and Western blotting, it is suggested that almost all detectable eye lens crystallins are prone to aggregation by homocysteinylation, while α-Crystallin comprises the main portion of lens protein aggregate. Overall this study may suggest lens protein homocysteinylation as a possible mechanism to explain the relationship between hyperhomocysteinimia and some impairments of the visual system.