title: [Selenium and cataract--risk factor or useful dietary supplement?].
abstract: BACKGROUND
  The exact role of selenium in cataract development is still unclear. Both protective and toxic effects and mechanisms have been postulated in the past. Accordingly, the selenium contents in human lenses and blood sera in different forms of cataract were investigated.
  
  
  METHODS
  123 patients (76 female and 37 male) with a mean age of 69.8 years (range: 17 to 91 years) were enrolled in this study. Overall, 84 lenses (after ECCE) and 110 blood serum samples were investigated by atomic absorption spectroscopy. Interpretation of data was accompanied by exact preoperative investigations including Scheimpflug techniques.
  
  
  RESULTS
  A significant increase of selenium content of the lenses was found with increasing lens opacification and colouration. Lenses with a mature cataract showed the highest selenium contents in the lens compared to other cataract forms. Opposite results were detected in blood serum. Lenses of diabetics showed already at a younger age changes in selenium content. Smokers showed both decreased selenium contents in the lens and decreased selenium concentration in blood serum.
  
  
  CONCLUSIONS
  An obvious correlation between the type of cataract and selenium content of the lens seems to exist. The question by which mechanism selenium acts directly or by selenium-dependent enzymes acts lens opacification remains speculative up to now.
authors.affiliation: Klinik für Augenheilkunde, Universitätsklinikum Jena, Bachstrasse 18, 07743 Jena. jens.dawczynski@med.uni-jena.de
authors.forename: J
authors.initials: J
authors.lastname: Dawczynski
authors.forename: K
authors.initials: K
authors.lastname: Winnefeld
authors.forename: E
authors.initials: E
authors.lastname: Königsdörffer
authors.forename: R
authors.initials: R
authors.lastname: Augsten
authors.forename: M
authors.initials: M
authors.lastname: Blum
authors.forename: J
authors.initials: J
authors.lastname: Strobel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D002386:Cataract / Q000175:diagnosis* / Q000378:metabolism*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007908:Lens, Crystalline / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods*; D012643:Selenium / Q000032:analysis*; D013223:Statistics as Topic
chemical_list: D015415:Biomarkers; D012643:Selenium