Vitamin B-6 nutriture and plasma diamine oxidase activity in pregnant Hispanic teenagers

Am J Clin Nutr. 1986 Dec;44(6):907-13. doi: 10.1093/ajcn/44.6.907.


Vitamin B-6 status was assessed by measuring erythrocyte glutamic-pyruvic transaminase (EGPT) indices in 122 pregnant Hispanic teenagers. Seventeen percent were vitamin B-6 deficient (EGPT indices greater than 1.25) at the initial interview (first or second trimester). A daily supplement of 5 mg vitamin B-6, beginning at initial interview, did not reduce prevalence of vitamin B-6 deficiency at final interview (third trimester). No association was found between EGPT indices greater than 1.25 and the outcome of pregnancy. The activity of diamine oxidase (DAO), a vitamin B-6-dependent enzyme produced by the placental decidua, was measured in maternal plasma. At initial and final interviews, plasma-DAO activity was increased by in vitro addition of pyridoxal-5'-phosphate. The activity in early pregnancy was positively associated with dietary vitamin B-6 intake and was lower in teenagers with EGPT indices greater than 1.25 at the final interview. Findings suggest that plasma-DAO activity is influenced by vitamin B-6 status.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Alanine Transaminase / blood
  • Amine Oxidase (Copper-Containing) / blood*
  • Female
  • Hispanic or Latino
  • Humans
  • Pregnancy
  • Pregnancy Complications / drug therapy
  • Pregnancy Complications / enzymology
  • Pregnancy Complications / ethnology*
  • Pregnancy in Adolescence*
  • Pyridoxal Phosphate / pharmacology
  • Pyridoxine / blood
  • Pyridoxine / therapeutic use
  • Vitamin B Deficiency / drug therapy
  • Vitamin B Deficiency / enzymology
  • Vitamin B Deficiency / ethnology*


  • Pyridoxal Phosphate
  • Amine Oxidase (Copper-Containing)
  • Alanine Transaminase
  • Pyridoxine