Glucosylation of human lens protein and cataractogenesis.

Examination of glucosylation of lens protein was conducted utilizing tritiated BH₄^?. The overall results indicate that approximately 0.20 moles of tritium were incorporated per mole of protein. Similar results were obtained with normal and senile cataractous lenses with varying degrees of opacity. Furthermore no difference in the ³H incorporation was observed between soluble and insoluble protein fractions derived from these lenses. Investigation of selected polypeptides isolated from the senile cataracts gave comparable results. Protein isolated from diabetic lenses had only slightly higher levels of tritium incorporation, giving an average value of 0.27 moles per mole of protein. Analyses of the tritiated products indicate that approximately 50% of the incorporation is probably due to reduction of other types of compounds. These results suggest that glucosylation does not appear to be a primary factor in cataract formation.