Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, United States; Department of Internal Medicine, Mayo Clinic, Rochester, MN, 55905, United States.
Department of Family Medicine, Mayo Clinic, Rochester, MN, 55905, United States.
Bone. 2018 May;110:321-325. doi: 10.1016/j.bone.2018.02.024. Epub 2018 Feb 24.
Supplementing lactating mothers with high doses of vitamin D can adequately meet vitamin D requirements of the breastfed infant. We compared the effect of bolus versus daily vitamin D dosing in lactating mothers on vitamin D catabolism. We hypothesized that catabolism of 25(OH)D to 24,25(OH)D would be greater in the bolus than in the daily dose group.
DESIGN, SETTING AND PATIENTS: Randomized controlled trial (clinicaltrials.govNCT01240265) in 40 lactating women.
Subjects were randomized to receive vitamin D orally, either a single dose of 150,000IU or 5000IU daily for 28days. Vitamin D metabolites were measured in serum and breast milk at baseline, 1, 3, 7, 14 and 28days.
Temporal changes in the serum 24,25(OH)D/25(OH)D ratio.
The concentration of serum 24,25(OH)D was directly related to that of 25(OH)D in both groups (r=0.63; p<0.001). The mean (±SD) 24,25(OH)D/25(OH)D ratio remained lower at all time points than baseline values in the daily dose group (0.093±0.024, 0.084±0.025, 0.083±0.024, 0.080±0.020, 0.081±0.023, 0.083±0.018 at baseline, 1, 3, 7, 14, and 28days, respectively). In the single dose group, the increase in 24,25(OH)D lagged behind that of 25(OH)D, but the 24,25(OH)D/25(OH)D values (0.098±0.032, 0.067±0.019, 0.081±0.017, 0.092±0.024, 0.103±0.020, 0.106±0.024, respectively) exceeded baseline values at 14 and 28days and were greater than the daily dose group at 14 and 28days (p=0.003). The 24,25(OH)D/25(OH)D ratio remained in the normal range with both dosing regimens. Greater breast milk vitamin D values in the single dose group were inversely associated with the 24,25(OH)D/25(OH)D ratio (r=0.14, p<0.001), but not with daily dosing.
After a 14-day lag, a single high dose of vitamin D led to greater production of 24,25(OH)D, presumably via induction of the 24-hydroxylase enzyme (CYP24A1), relative to the 25(OH)D value than did daily vitamin D supplementation, and this effect persisted for at least 28days after vitamin D administration. A daily dose of vitamin D may have more lasting effectiveness in increasing 25(OH)D with lesser diversion of 25(OH)D to 24,25(OH)D than does larger bolus dosing.
给哺乳期妇女补充大剂量的维生素 D 可以充分满足母乳喂养婴儿对维生素 D 的需求。我们比较了哺乳期母亲补充维生素 D 时，大剂量冲击与每日剂量对维生素 D 代谢的影响。我们假设与每日剂量组相比，25(OH)D 向 24,25(OH)D 的代谢速度在冲击剂量组中会更快。
设计、地点和患者：在 40 名哺乳期妇女中进行的随机对照试验（clinicaltrials.govNCT01240265）。
受试者随机接受口服维生素 D，单次剂量为 150,000IU 或 5000IU，连续 28 天。在基线、第 1、3、7、14 和 28 天测量血清和母乳中的维生素 D 代谢物。
血清 24,25(OH)D/25(OH)D 比值的时间变化。
两组血清 24,25(OH)D 浓度与 25(OH)D 浓度直接相关（r=0.63；p<0.001）。与基线值相比，每日剂量组在所有时间点的 24,25(OH)D/25(OH)D 比值均较低（0.093±0.024、0.084±0.025、0.083±0.024、0.080±0.020、0.081±0.023、0.083±0.018，分别为第 1、3、7、14 和 28 天）。在单次剂量组中，24,25(OH)D 的增加滞后于 25(OH)D，但 24,25(OH)D/25(OH)D 值（0.098±0.032、0.067±0.019、0.081±0.017、0.092±0.024、0.103±0.020、0.106±0.024，分别为第 14 和 28 天）在第 14 和 28 天超过了基线值，且在第 14 和 28 天大于每日剂量组（p=0.003）。两种剂量方案的 24,25(OH)D/25(OH)D 比值均在正常范围内。单次剂量组中母乳中的维生素 D 值越高，24,25(OH)D/25(OH)D 比值越低（r=0.14，p<0.001），但与每日剂量无关。
在 14 天的滞后期后，与每日维生素 D 补充相比，单次高剂量的维生素 D 会导致 24,25(OH)D 的产生增加，可能是通过诱导 24-羟化酶（CYP24A1），而 25(OH)D 值相对于 25(OH)D 值更高，这种作用在维生素 D 给药后至少持续 28 天。与大剂量冲击相比，每日剂量的维生素 D 可能更持久地增加 25(OH)D，而将 25(OH)D 转化为 24,25(OH)D 的量较少。
