Vitamin D in health and disease
Vitamin D in health and disease
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DOI：
10.2215/cjn.01160308
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发表时间：
2008-09-01
影响因子：
9.8
通讯作者：
Heaney, Robert P.
中科院分区：
文献类型：
--
作者：
Heaney, Robert P.
维生素D通过内分泌机制（钙吸收的调节）和自分泌机制（基因表达的促进）在体内发挥作用。前者通过循环骨化三醇起作用，而后者占每天维生素代谢利用的80%以上，仅在细胞内产生、使用和降解骨化三醇。在终末期肾病患者中，内分泌机制被有效地禁用;然而，只要患者具有足够的25（OH）D血清水平，自分泌机制就能够正常发挥作用，其功能完全依赖于25（OH）D。出于这个原因，骨化三醇及其类似物在管理此类患者的维生素D需求方面不构成足够的替代品。最佳血清25（OH）D水平大于32 ng/mL（80 nmol/L）。低25（OH）D状态的后果包括各种慢性疾病的风险增加，从高血压到糖尿病再到癌症。确保足够的维生素D状态的最安全和最经济的方法是口服天然维生素D。(Both每日和间歇性方案效果良好。）预计每天每增加100 IU维生素D，血清25（OH）D将升高约1 ng/mL（2.5 nmol/L）。最近的数据表明，胆钙化醇（维生素D-3）比麦角钙化醇（维生素D-2）有效得多，维生素D-3的安全摄入量上限为10 000 IU/d。
Vitamin D functions in the body through both an endocrine mechanism (regulation of calcium absorption) and an autocrine mechanism (facilitation of gene expression). The former acts through circulating calcitriol, whereas the latter, which accounts for more than 80% of the metabolic utilization of the vitamin each day, produces, uses, and degrades calcitriol exclusively intracellularly. In patients with end-stage kidney disease, the endocrine mechanism is effectively disabled; however, the autocrine mechanism is able to function normally so long as the patient has adequate serum levels of 25(OH)D, on which its function is absolutely dependent. For this reason, calcitriol and its analogs do not constitute adequate replacement in managing vitamin D needs of such patients. Optimal serum 25(OH)D levels are greater than 32 ng/mL (80 nmol/L). The consequences of low 25(OH)D status include increased risk of various chronic diseases, ranging from hypertension to diabetes to cancer. The safest and most economical way to ensure adequate vitamin D status is to use oral dosing of native vitamin D. (Both daily and intermittent regimens work well.) Serum 25(OH)D can be expected to rise by about 1 ng/mL (2.5 nmol/L) for every 100 IU of additional vitamin D each day. Recent data indicate that cholecalciferol (vitamin D-3) is substantially more potent than ergocalciferol (vitamin D-2) and that the safe upper intake level for vitamin D-3 is 10,000 IU/d.