title: Serum vitamin C concentration is influenced by haptoglobin polymorphism and iron status in Chinese.
abstract: BACKGROUND
  Vitamin C is a powerful antioxidant (free radical scavenger). Apart from the diet, other factors regulating its catabolism may affect its serum concentration. Haptoglobin (Hp) is a plasma protein participating in iron metabolism. It shows a genetic polymorphism which shows marked geographical differences. We investigated the relationship between vitamin C, iron status and haptoglobin polymorphism in Chinese men and women.
  
  
  METHODS
  Iron status markers were compared according to Hp phenotypes determined by chemiluminescence detection in 110 healthy Chinese subjects. The concentration of haptoglobin was determined using an immunoturbidimetric method. Serum vitamin C was tested by a 2,4-dinitrophenylhydrazine based method.
  
  
  RESULTS
  In Chinese, the haptoglobin phenotype distribution was 10.0% Hp 1-1, 33.6% Hp 2-1, and 56.4% Hp 2-2. In the study group, serum vitamin C concentration was associated with haptoglobin type, showing lowest values in serum from Hp 2-2 subjects in males (p=0.028, ANOVA). In contrast to Hp phenotype, Hp concentration did not affect vitamin C concentration. Hp 2-2 shows higher haptoglobin (p=0.002 (ANOVA)) than individuals with the other types. Furthermore, vitamin C was influenced by (log)ferritin levels. In Chinese, vitamin C is influenced by haptoglobin polymorphism and iron status.
  
  
  CONCLUSIONS
  The present findings support the role of non-nutritional factors in vitamin C status.
authors.affiliation: Department of Chemistry, Beijing Normal University, Beijing 100875, PR China.
authors.forename: Na
authors.initials: N
authors.lastname: Na
authors.forename: Joris R
authors.initials: JR
authors.lastname: Delanghe
authors.forename: Youri E C
authors.initials: YE
authors.lastname: Taes
authors.forename: Mathieu
authors.initials: M
authors.lastname: Torck
authors.forename: Willy R G
authors.initials: WR
authors.lastname: Baeyens
authors.forename: Jin
authors.initials: J
authors.lastname: Ouyang
mesh_terms: D001205:Ascorbic Acid / Q000097:blood*; D002681:China; D006242:Haptoglobins / Q000235:genetics*; D006801:Humans; D007501:Iron / Q000097:blood*; D011110:Polymorphism, Genetic
chemical_list: D006242:Haptoglobins; D007501:Iron; D001205:Ascorbic Acid