Vitamin D kinetics in nonpregnant and pregnant women after a single oral dose of trideuterated vitamin D3.
J Steroid Biochem Mol Biol
; 216: 106034, 2022 02.
Article
em En
| MEDLINE
| ID: mdl-34843870
ABSTRACT
The plasma pool of the hormone 1,25-dihydroxyvitamin D (1,25(OH)2D) is increased throughout most of human pregnancy. Mechanisms behind this adaptation are unclear, in part due to limited data on vitamin D kinetics during pregnancy. Stable isotopes make it possible to study vitamin D kinetics in vulnerable study populations like pregnant women. We conducted a pilot study of vitamin D kinetics in nonpregnant and pregnant women. We evaluated a clinical protocol and developed analytical methods to assess the serum appearance and disappearance of trideuterated vitamin D3 (d3-vitamin D3) and trideuterated 25-hydroxyvitamin D3 (d3-25(OH)D3) after a single oral dose of 25 µg of [6,19,19-2H]-vitamin D3 (d3-vitamin D3). Blood was collected at baseline and 2, 4, 6, 24, 168, 264, and 456 hours post-dosing. We then described the serum kinetic profiles of d3-vitamin D3 and d3-25(OH)D3 in nonpregnant and pregnant women. Serum kinetic profiles of d3-vitamin D3 and d3-25(OH)D3 followed a time course in line with previous pharmacokinetic studies. There was marked variability between participants in the area under the concentration-time curve (AUC) of d3-25(OH)D3 over the 20-day study period. This AUC of d3-25(OH)D3 was positively correlated with the serum vitamin D binding protein (DBP) concentration, which was higher in pregnant compared with nonpregnant women. The mean serum half-life of 25(OH)D3 was longer but not significantly different in pregnant women (18.8 days) compared with nonpregnant women (13.6 days). Our pilot study demonstrated that a single oral dose of 25 µg of d3-vitamin D3 can be used to study vitamin D kinetics. Serum DBP concentration is an important predictor of vitamin D kinetics, and more research is needed to fully understand the significance of elevated DBP concentration during pregnancy.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Calcitriol
/
Gravidez
/
Colecalciferol
Tipo de estudo:
Clinical_trials
/
Guideline
Limite:
Adult
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Female
/
Humans
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Pregnancy
Idioma:
En
Revista:
J Steroid Biochem Mol Biol
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Estados Unidos