Low ratio of S-adenosylmethionine to S-adenosylhomocysteine is associated with vitamin deficiency in Brazilian pregnant women and newborns

Background: Pregnant women with low cobalamin concentrations are unable to provide the necessary amount of cobalamin to their fetuses. The effect of low maternal cobalamin concentrations on transmethylation metabolism in pregnant women and their newborns is unknown.Objective: We investigated the rel...

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Bibliographic Details
Authors: Guerra-Shinohara, Elvira Maria, Morita, Olga E., Peres, Sabrina, Pagliusi, Regina A., Sampaio Neto, Luiz Ferraz de [UNIFESP], D'Almeida, Vania [UNIFESP], Irazusta, Silvia P., Allen, Robert H., Stabler, Sally P.
Format: article
Status:Published version
Publication Date:2004
Country:Brasil
Institution:Universidade Federal de São Paulo (UNIFESP)
Repository:Repositório Institucional da UNIFESP
Language:English
OAI Identifier:oai:repositorio.unifesp.br:11600/42267
Online Access:http://ajcn.nutrition.org/content/80/5/1312.full
http://repositorio.unifesp.br/handle/11600/42267
Access Level:Open access
Keyword:cobalamin
folate
homocysteine
methylmalonic acid
S-adenosylhomocysteine
S-adenosylmethionine
pregnant women
newborns
Description
Summary:Background: Pregnant women with low cobalamin concentrations are unable to provide the necessary amount of cobalamin to their fetuses. The effect of low maternal cobalamin concentrations on transmethylation metabolism in pregnant women and their newborns is unknown.Objective: We investigated the relation between maternal and neonatal cobalamin concentrations and changes in total homocysteine (tHcy), S-adenosylmethionine (SAM), and S-adenosylhomocysteine (SAH).Design: Hematologic data and concentrations of cobalamin, red blood cell folate, serum folate, tHcy, methylinalonic acid, SAM, SAH, and other metabolites were measured in 119 serum specimens from pregnant Brazilian women (gestational age: 37-42 wk) and their newborns' placental veins at the time of delivery.Results: The tHcy concentrations were higher in placental vein serum from newborns whose mothers had low cobalamin. Serum SAH concentrations were elevated and serum SAM and methionine concentrations were decreased in pregnant women with lower cobalamin concentrations. SAM:SAH was significantly decreased in both cobalamin-deficient pregnant women and their newborns.Conclusions: Lower maternal cobalamin concentrations are associated with higher tHcy and lower SAM:SAH in newborns. Because SAM:SAH is closely linked with the activity of numerous enzymatic methylation reactions, these results suggest that methylation could be impaired in cobalamin-deficient pregnant women and their newborns.