title: Selenium and glutathione peroxidase with beta-thalassemia major.
abstract: BACKGROUND
  Chronic iron-overload is a major cause of organ failure and mortality worldwide, but its pathogenesis remains to be elucidated.
  
  
  OBJECTIVE
  To examine the relationship between various measures of body iron burden, selenium concentrations and glutathione peroxidase (GPx) activity in patients with beta-thalassemia major.
  
  
  METHODS
  An age- and gender-matched case control study was conducted to examine the relationship between various measures of body iron burden (serum ferritin, transferrin saturation, total serum iron), plasma concentrations of selenium and glutathione peroxidase (GPx) activity in patients with homozygous beta-thalassemia major (N = 20) and healthy controls (N = 10). Ten patients received the experimental oral chelator L1 and ten received chelation therapy with subcutaneous desferal.
  
  
  RESULTS
  Significantly decreased plasma concentrations of selenium (microg/L) were observed in patients chelated with L1 (1.4 +/- 0.2) or desferal (1.4 +/- 0.1), in comparison to healthy controls (1.8 +/- 0.1, p < 0.01). Significantly decreased plasma activity of GPx (microg/L) was observed in patients chelated with L1 (166 +/- 43) or desferal (178 +/- 46), in comparison to healthy controls (296 +/- 22, p < 0.001). Significantly increased concentrations of all measures of body iron burden were observed in beta-thalassemia patients, in comparison to healthy controls (p < 0.001).
  
  
  CONCLUSIONS
  Patients with beta-thalassemia major and chronic iron-overload have decreased concentrations of the essential element selenium and the protective selenium-dependent antioxidant enzyme GPx. Additional research examining the effects of dietary antioxidant supplementation with selenium on these aforementioned parameters in patients with beta-thalassemia major and iron-overload is warranted.
authors.affiliation: School of Nursing, Queen's University, Kingston, Ontario, Canada.
authors.forename: W J
authors.initials: WJ
authors.lastname: Bartfay
authors.forename: E
authors.initials: E
authors.lastname: Bartfay
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002614:Chelating Agents / Q000627:therapeutic use; D015913:Chelation Therapy; D003676:Deferoxamine / Q000627:therapeutic use; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood*; D006801:Humans; D008297:Male; D012643:Selenium / Q000097:blood*; D017086:beta-Thalassemia / Q000097:blood* / Q000628:therapy
chemical_list: D002614:Chelating Agents; D005979:Glutathione Peroxidase; D012643:Selenium; D003676:Deferoxamine