Accumulation of the hydroxyl free radical markers meta-, ortho-tyrosine and DOPA in cataractous lenses is accompanied by a lower protein and phenylalanine content of the water-soluble phase

  title={Accumulation of the hydroxyl free radical markers meta-, ortho-tyrosine and DOPA in cataractous lenses is accompanied by a lower protein and phenylalanine content of the water-soluble phase},
  author={Gergő Attila Moln{\'a}r and Vanda Nemes and Zsolt Bir{\'o} and Andrea Lud{\'a}ny and Zolt{\'a}n Wagner and Istv{\'a}n Wittmann},
  journal={Free Radical Research},
  pages={1359 - 1366}
Post-translational modifications of lens proteins play a crucial role in the formation of cataract during ageing. The aim of our study was to analyze protein composition of the cataractous lenses by electrophoretic and high-performance liquid chromatographic (HPLC) methods. Samples were obtained after extracapsular cataract surgery performed by phacoemulsification technique from cataract patients with type 2 diabetes mellitus (DM CAT, n = 22) and cataract patients without diabetes (non-DM CAT… 
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Simultaneous chemical and photochemical protein crosslinking induced by irradiation of eye lens proteins in the presence of ascorbate: the photosensitizing role of an UVA-visible-absorbing decomposition product of vitamin C.
  • F. Ávila, B. Friguet, Eduardo Silva
  • Biology
    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology
  • 2010
The results of this work indicate that ascorbate oxidation, which generates the AGEs responsible for the chemical crosslinking of the lens proteins, also simultaneously produces a chromophore that can act as a photosensitizer, further increasing the proteinCrosslinking.
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The correlation in lens fluorescence was greater in monozygotic twins than dizygotic twins indicating a genetically predetermined susceptibility for the accumulation of fluorophores in the lens, the relative importance of which was found to increase with age.
Hydroxyl radical mediated damage to proteins, with special reference to the crystallins.
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The lens in diabetes
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