Hollis B W, Lowery J W, Pittard W B, Guy D G, Hansen J W
Department of Pediatrics, Medical University of South Carolina, Charleston, USA.
J Clin Endocrinol Metab. 1996 Apr;81(4):1385-8. doi: 10.1210/jcem.81.4.8636338.
This study was undertaken to investigate the utility of vitamin D3-palmitate as a nutritional supplement and thus define the intestinal absorption profile of vitamin D2 and vitamin D3 liberated after its cleavage from vitamin D3-palmitate in the human infant at various postnatal ages. The subjects for study consisted of 48 normal infants that were simultaneously administered 0.07 and 0.08 micromol/kg BW vitamin D as vitamin D3-palmitate and nonesterified vitamin D2 respectively, by orogastric tube. Blood samples were obtained before and 6, 12, and 24 h postadministration and analyzed simultaneously for vitamins D2 and D3. For data analysis, the infants were divided into two groups based on postnatal age: group 1, 1 day of age; and group 2, more than 10 days of age. Data were analyzed using the integrated peak area under the absorption curve for each subject. All subjects demonstrated the ability to absorb vitamin D after oral administration, although postnatal age as well as vitamin form had a profound effect on the absorption of vitamin D2 and vitamin D3 liberated from vitamin D3-palmitate. Nonesterified vitamin D2 is well absorbed both in very young and older infants, although absorption efficiency increases with age, perhaps due to increased bile acid secretion. Liberation of vitamin D3 from vitamin D3-palmitate was shown to increase, perhaps due to gastrointestinal tract maturation, beyond 10 days of age, probably coinciding with the secretion of intestinal esterases. Our data indicate that both forms of the orally administered vitamin approach equivalency in their abilities to elevate circulating vitamin D levels in the human infant at a postnatal age of approximately 89 days. Thus, vitamin D3-palmitate would appear not to be dietarily equivalent to free vitamin D as a nutritional source of vitamin D in the human neonate.
本研究旨在探讨维生素D3 - 棕榈酸酯作为营养补充剂的效用，从而确定在不同出生后年龄的人类婴儿中，维生素D3 - 棕榈酸酯裂解后释放的维生素D2和维生素D3的肠道吸收情况。研究对象包括48名正常婴儿，通过鼻胃管分别同时给予0.07和0.08微摩尔/千克体重的维生素D，形式分别为维生素D3 - 棕榈酸酯和非酯化维生素D2。在给药前以及给药后6、12和24小时采集血样，并同时分析维生素D2和D3。为了进行数据分析，根据出生后年龄将婴儿分为两组：第1组，出生1天；第2组，出生超过10天。使用每个受试者吸收曲线下的积分峰面积进行数据分析。所有受试者口服维生素D后均表现出吸收能力，尽管出生后年龄以及维生素形式对从维生素D3 - 棕榈酸酯释放的维生素D2和维生素D3的吸收有深远影响。非酯化维生素D2在非常年幼和较大婴儿中均能很好地吸收，尽管吸收效率随年龄增加，这可能是由于胆汁酸分泌增加所致。维生素D3从维生素D3 - 棕榈酸酯的释放显示在出生10天后增加，这可能是由于胃肠道成熟，可能与肠道酯酶的分泌同时发生。我们的数据表明，在出生后约89天的人类婴儿中，两种口服形式的维生素在提高循环维生素D水平的能力上接近等效。因此，作为人类新生儿维生素D的营养来源，维生素D3 -棕榈酸酯在饮食上似乎与游离维生素D不等同。
