title: Presence and distribution of L-kynurenine aminotransferases immunoreactivity in human cataractous lenses.
abstract: OBJECTIVE
  To investigate the presence and distribution of l-kynurenine aminotransferases immunoreactivity in human and animal lenses during cataract formation.
  
  
  METHODS
  Immunohistochemistry was conducted using polyclonal antibodies against KAT I, KAT II and KAT III on sections of 26 anterior capsules from patients undergoing surgical treatment of anterior subcapsular cataract (ASC) and 22 cataractous lenses from human eyes enucleated because of choroidal malignant melanoma. Additionally, the eyes of 11-month-old DBA/2J mice (6 eyes) were investigated (with KAT I and II). Ten clear human lenses and four BL6 mice lenses were used as controls. Spatial immunoreactivity patterns of enzymes were compared with Periodic Acid - Schiff (PAS)-stained sections.
  
  
  RESULTS
  Immunohistochemical analysis revealed presence of KAT I, KAT II and KAT III in extracellular structures of all studied types of cataract in human eyes showing specific pattern of the stain. In cortical cataract, immunoreactivity was observed on cortical lens fibres. In nuclear cataract, KAT II revealed stronger and diffused staining than KAT I. Additionally, both KAT showed more pronounced staining at the edge of small clefts. In normal human lenses, KAT I, II and III, immunoreactivity was not observed. Presence of KAT I and KAT II in the intercellular substance of DBA/2J mice cataract was observed. In BL6 mice lenses without cataract, only weak KAT I and KAT II staining was observed.
  
  
  CONCLUSIONS
  Presence of l-kynurenine aminotransferases in extracellular matrix (ECM) during human cataract formation suggests that products of l-kynurenine pathway might be involved in mechanisms of cataractogenesis.
authors.affiliation: Department of Ophthalmology, University of Erlangen-Nuernberg, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Rejdak
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Oleszczuk
authors.forename: Carmen
authors.initials: C
authors.lastname: Rummelt
authors.forename: Waldemar A
authors.initials: WA
authors.lastname: Turski
authors.forename: Tomasz
authors.initials: T
authors.lastname: Choragiewicz
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Nowomiejska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Ksiazek
authors.forename: Sebastian
authors.initials: S
authors.lastname: Thaler
authors.forename: Tomasz
authors.initials: T
authors.lastname: Zarnowski
authors.forename: Etsuo
authors.initials: E
authors.lastname: Okuno
authors.forename: Pawel
authors.initials: P
authors.lastname: Grieb
authors.forename: Eberhart
authors.initials: E
authors.lastname: Zrenner
authors.forename: Friedrich
authors.initials: F
authors.lastname: Kruse
authors.forename: Anselm G M
authors.initials: AG
authors.lastname: Junemann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002386:Cataract / Q000145:classification / Q000201:enzymology*; D002387:Cataract Extraction; D005109:Extracellular Matrix / Q000201:enzymology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007908:Lens, Crystalline / Q000201:enzymology*; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D008875:Middle Aged; D000637:Transaminases / Q000378:metabolism*; D055815:Young Adult
chemical_list: D000637:Transaminases; C021481:kynurenine-oxoglutarate transaminase
keywords: DBA/2J mice; cataractogenesis; human lens; immunohistochemical localization; kynurenine aminotransferases; l-kynurenine