Journal des biomarqueurs moléculaires et du diagnostic

Biochemical and Molecular Markers of Congenital and Senile Cataractous Lenses

Abstract

Hassan IH El-Sayyad*, Tag-Eldin YM, Soad A Khalifa, Amal A AbdEl-Wahab, and Taher MG El-Desoky

Background: Cataractous lenses represent one of the main public health problem involved in impairing vision. Different multiactorial agents are involved in its development.

Material and methods: In this study, 15 congenital and 56 senile cataractous lenses obtained post-operative surgery from patients admitted to Ophthalmic Center, Mansoura University Hospital, Mansoura, Egypt were investigated. Non-opaque lenses were extracted from infants aging 8 M-2 y-old (n=5) and young adult 20-30 years (n=6) after accident death of 1-4 hours. Medical Research Ethics committee, Egypt, approved the study protocol. A written informed consent had been taken beforehand from all patients or parent of infants to use their extracted lens experimentally after operation. Biochemical analysis was carried out to outline the differences between congenital and senile cataractous lenses in comparison with the control. Different parameters were investigated including amino acids, protein carbonylation, glycation end products, phospholipids, caspases, endothelin, heat shock protein, sorbitol, fructose and comet assay for single DNA damaged and scanning electron microscopy of lens fibres were investigated.

Results: The findings revealed marked increase of protein carbonylation, glycation end products, phospholipids, caspases, endothelin, heat shock protein, sorbitol and fructose coincides with single DNA damage. Aspartic, alanine, cysteine, isoleucine, leucine, methionine, tyrosine, histidine, tryptophan, valine and phenylalanine were significantly decreased in senile cataractous lenses in comparison with control and congenital cataracts. Scanning electron microscopy revealed abnormal disorganized lens fibers in cataractous lens which become widely separated and possessed deformation of ball and sockets. Some lens fibers possessed apparent accumulation of calcium salts.

Conclusions: Different factors are involved in cataractous formation coincides with increased of glycation end products and caspases reflecting apoptosis of lens.