title: Activity loss of glutathione synthesis enzymes associated with human subcapsular cataract.
abstract: OBJECTIVE
  To assess the activities of the two enzymes required for glutathione synthesis, gamma-glutamylcysteine synthetase and glutathione synthetase, in various forms of human cataracts.
  
  
  METHODS
  The Cooperative Cataract Research Group cataract classification method and standard enzyme assay procedures were used.
  
  
  RESULTS
  An inverse relationship was shown between residual activity of each of the glutathione synthesis enzymes and degree of subcapsular cataract. A weaker inverse relationship existed between glutathione synthetase activity and supranuclear and nuclear cataracts. No other parameters yielded comparable correlations with the activity of either enzyme.
  
  
  CONCLUSIONS
  Activity loss of the glutathione synthesis enzymes is associated with human subcapsular cataract formation.
authors.affiliation: Ophthalmology Department, University of Minnesota, Minneapolis 55455.
authors.forename: W B
authors.initials: WB
authors.lastname: Rathbun
authors.forename: A J
authors.initials: AJ
authors.lastname: Schmidt
authors.forename: A M
authors.initials: AM
authors.lastname: Holleschau
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002386:Cataract / Q000201:enzymology*; D005721:Glutamate-Cysteine Ligase / Q000378:metabolism*; D005978:Glutathione / Q000096:biosynthesis; D005981:Glutathione Synthase / Q000378:metabolism*; D006801:Humans; D007903:Lens Capsule, Crystalline / Q000201:enzymology*; D007908:Lens, Crystalline / Q000201:enzymology / Q000378:metabolism; D008875:Middle Aged
chemical_list: D005721:Glutamate-Cysteine Ligase; D005981:Glutathione Synthase; D005978:Glutathione