Maternal vitamin D biomarkers are associated with maternal and fetal bone turnover among pregnant women consuming controlled amounts of vitamin D, calcium, and phosphorus.
Maternal vitamin D biomarkers are associated with maternal and fetal bone turnover among pregnant women consuming controlled amounts of vitamin D, calcium, and phosphorus.
复制标题
孕妇维生素D生物标志物与食用受控数量的维生素D，钙和磷的孕妇的母体和胎儿骨转换有关。
DOI：
10.1016/j.bone.2016.12.002
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发表时间：
2017-02
期刊：
影响因子：
4.1
通讯作者：
Caudill MA
中科院分区：
文献类型：
--
作者：
Park H;Brannon PM;West AA;Yan J;Jiang X;Perry CA;Malysheva O;Mehta S;Caudill MA
维生素D在钙稳态中起着核心作用；然而，由于缺乏对其他已知影响骨代谢的营养素进行严格控制的研究，维生素D与怀孕期间骨转换的关系仍不清楚。同样，先前关于怀孕对骨转换的影响相对于非怀孕状态的调查可能被这些营养素的不同摄入量搞混了。在受控摄入量研究的基础上，本研究试图量化孕妇维生素D生物标志物与怀孕(与未怀孕)妇女及其胎儿在维生素D及相关营养素摄入量相等和充足的条件下骨转换生化标志物之间的关系。还检查了妊娠晚期骨转换标志物的变化。健康孕妇(妊娠26-29周；n=26)和未怀孕(n=21)妇女每天摄入511IU维生素D、1.6g钙和1.9g磷，持续10周，同时参加两种胆碱剂量的对照喂养研究。基于对有影响的协变量(例如，体重指数、种族和季节)进行调整的线性混合模型，怀孕妇女的骨吸收标志物浓度比未怀孕妇女高50-150%(P<；0.001)。在孕妇中，研究期间母体25(OH)D的增加与研究结束时较低的骨钙素和脱氧吡啶酚，以及较高的胎儿骨钙素有关(P<；0.020)。研究结束时，母体游离25(OH)D、1，25(OH)2D和24，25(OH)2D与母体NTx呈负相关(P≤0.063)，母体游离25(OH)D和24，25(OH)2D与胎儿环磷酰胺呈正相关(P≤0.021)。同样，研究结束时，母体3-EPI-25(OH)D3与母体Ntx和脱氧吡啶酚呈负相关(P≤0.037)。这些由孕妇体内较高的维生素D生物标志物浓度导致的骨吸收标志物的下降与她们经白蛋白校正的血清钙浓度的上升相吻合，这表明钙向胎儿的转移没有受到影响。值得注意的是，在未怀孕的女性中，这些关联都没有达到统计学意义。总体而言，我们的研究结果表明，获得更高的孕妇维生素D生物标志物浓度可能会减弱妊娠晚期的骨吸收，同时确保向胎儿提供足够的钙。
Vitamin D plays a central role in calcium homeostasis; however, its relationship with bone turnover during pregnancy remains unclear due to a lack of studies that have rigorously controlled for other nutrients known to influence bone metabolism. Similarly, prior investigations of the effect of pregnancy on bone turnover relative to the nonpregnant state may have been confounded by varying intakes of these nutrients. Nested within a controlled intake study, the present investigation sought to quantify associations between maternal vitamin D biomarkers and biochemical markers of bone turnover among pregnant (versus nonpregnant) women and their fetuses under conditions of equivalent and adequate intakes of vitamin D and related nutrients. Changes in markers of bone turnover across the third trimester were also examined. Healthy pregnant (26–29 wk gestation; n=26) and nonpregnant (n=21) women consumed 511IU vitamin D/d, 1.6g calcium/d, and 1.9g phosphorus/d for 10 weeks while participating in a controlled feeding study featuring two choline doses. Based on linear mixed models adjusted for influential covariates (e.g., BMI, ethnicity, and season), pregnant women had 50–150% higher (P<0.001) concentrations of bone resorption markers than nonpregnant women. Among pregnant women, increases in maternal 25(OH)D across the study period were associated (P<0.020) with lower osteocalcin and deoxypyridinoline at study-end, and higher fetal osteocalcin. In addition, maternal free 25(OH)D, 1,25(OH)2D, and 24,25(OH)2D tended to be negatively associated (P≤0.063) with maternal NTx at study-end, and maternal free 25(OH)D and 24,25(OH)2D were positively associated (P≤0.021) with fetal CTx. Similarly, maternal 3-epi-25(OH)D3 was negatively related (P≤0.037) to maternal NTx and deoxypyridinoline at study-end. These declines in bone resorption markers resulting from higher vitamin D biomarker concentrations among pregnant women coincided with increases in their albumin-corrected serum calcium concentrations, indicating that calcium transfer to the fetus was uncompromised. Notably, none of these associations achieved statistical significance among nonpregnant women. Overall, our study findings suggest that achieving higher maternal concentrations of vitamin D biomarkers might attenuate third-trimester bone resorption while ensuring sufficient calcium delivery to the fetus.