Solomon Lawrence R
Section of Hematology, Department of Medicine, Yale University School of Medicine, 300 Cedar Street, New Haven, CT 06520, United Kingdom.
Blood Rev. 2007 May;21(3):113-30. doi: 10.1016/j.blre.2006.05.001. Epub 2006 Jul 11.
Although cobalamin (vitamin B12) was isolated almost 60 years ago, its biochemical, physiologic and neurologic effects remain incompletely defined. New observations suggest renal regulation of cobalamin metabolism; actions of cobalamin on nucleic acid and protein function; and a role for cobalamin in cytokine and growth factor regulation. Clinically, no gold standard has emerged for the diagnosis of cobalamin deficiency. Moreover, cobalamin resistance may occur in diabetes, renal insufficiency and advanced age, leading to functional cobalamin deficiency despite adequate cobalamin nutriture. Finally, high-dose cobalamin therapy may have salutary pharmacologic effects on neurologic function in a variety of disorders. Many studies lacked appropriate control groups. However, at this time, therapeutic trials with pharmacologic doses of cobalamin are suggested when findings consistent with cobalamin deficiency are present regardless of the results of diagnostic tests. While oral cobalamin immediate-release is adequate for many patients, its effectiveness in reversing neurologic abnormalities has yet to be established.
尽管钴胺素（维生素B12）在近60年前就已被分离出来，但其生化、生理及神经学效应仍未完全明确。新的观察结果提示了肾脏对钴胺素代谢的调节作用；钴胺素对核酸和蛋白质功能的影响；以及钴胺素在细胞因子和生长因子调节中的作用。临床上，尚未出现诊断钴胺素缺乏的金标准。此外，在糖尿病、肾功能不全及高龄人群中可能会出现钴胺素抵抗，导致尽管钴胺素营养充足但仍出现功能性钴胺素缺乏。最后，高剂量钴胺素治疗可能对多种疾病的神经功能具有有益的药理作用。许多研究缺乏合适的对照组。然而，此时，当出现与钴胺素缺乏相符的结果时，无论诊断测试结果如何，建议进行药理剂量钴胺素的治疗试验。虽然口服速释钴胺素对许多患者来说足够了，但其逆转神经异常的有效性尚未得到证实。
