title: Effects of photobleaching on selected advanced glycation end products in the human lens.
abstract: BACKGROUND
  Cataract is the leading cause of blindness, especially in the developing world. To ease access to treatment, we have proposed that cataract could be treated non-invasively by photobleaching of the chemically modified proteins responsible for cataract formation. The present study was aimed at examining the optical and biochemical effects of the proposed treatment.
  
  
  METHODS
  Human donor lenses were photobleaced using a 445 nm cw laser. Lens optical quality was assessed before and after photobleaching by light transmission and scattering. The concentration of the advanced glycation end products (AGEs) pentosidine, argpyrimidine, carboxymethyllysine, hydroimidazolone was measured.
  
  
  RESULTS
  Transmission increased and AGE-related fluorescence decreased significantly after photobleaching but no changes were observed in the concentration of the measured AGEs.
  
  
  CONCLUSIONS
  We found a significant effect of the photobleaching treatment on lens optical parameters but we could not associate the optical findings to a change in the concentration of the AGEs we measured. This finding suggests that other AGEs were responsible for the observed photobleaching of the human lens after laser treatment. The biochemical nature of the photochemical reactions associated with photobleaching remains to be elucidated.
authors.affiliation: Department of Ophthalmology, Glostrup Hospital, Ringvej 57, 2600, Glostrup, Denmark. holm03@gmail.com.
authors.forename: Thomas
authors.initials: T
authors.lastname: Holm
authors.affiliation: Department of Ophthalmology & Visual Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA. cibin.thoppilraghavan@ucdenver.edu.|Present address: Department of Ophthalmology, University of Colorado School of Medicine, 12800 East 19th Avenue, RC-1 North 5102, Aurora, CO, 80045, USA. cibin.thoppilraghavan@ucdenver.edu.
authors.forename: Cibin T
authors.initials: CT
authors.lastname: Raghavan
authors.affiliation: Department of Ophthalmology & Visual Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA. rooban.nahomi@ucdenver.edu.|Present address: Department of Ophthalmology, University of Colorado School of Medicine, 12800 East 19th Avenue, RC-1 North 5102, Aurora, CO, 80045, USA. rooban.nahomi@ucdenver.edu.
authors.forename: Rooban
authors.initials: R
authors.lastname: Nahomi
authors.affiliation: Department of Ophthalmology & Visual Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA. ram.nagaraj@ucdenver.edu.|Present address: Department of Ophthalmology, University of Colorado School of Medicine, 12800 East 19th Avenue, RC-1 North 5102, Aurora, CO, 80045, USA. ram.nagaraj@ucdenver.edu.
authors.forename: Ram H
authors.initials: RH
authors.lastname: Nagaraj
authors.affiliation: Department of Ophthalmology, Glostrup Hospital, Ringvej 57, 2600, Glostrup, Denmark. line.kessel@dadlnet.dk.
authors.forename: Line
authors.initials: L
authors.lastname: Kessel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006801:Humans; D007908:Lens, Crystalline / Q000378:metabolism*; D008875:Middle Aged; D038761:Photobleaching; D012542:Scattering, Radiation
chemical_list: D017127:Glycation End Products, Advanced