Ercalcidiol is a metabolite of vitamin D2 that reflects the nutritional status of vitamin D in the body[1]. Compared to vitamin D3 metabolites, Ercalcidiol has a shorter half-life and exhibits lower binding affinity to vitamin D-binding protein. Due to its relatively weaker potency, higher doses are required when used for therapeutic purposes[2]. Ercalcidiol is commonly employed for monitoring the efficacy of vitamin D2 treatment and managing disorders of calcium and phosphate homeostasis[3,4].
In vitro, Ercalcidiol (292.5nM) was incubated as a substrate in a renal homogenate system from rachitic chickens for 2h, where it was successfully metabolized by 1α-hydroxylase to produce 1α,25-(OH)2D2[5].
References:
[1] TUGCU G, CHAREHSAZ M, AYDIN A. Toxicological evaluation of ergocalciferol, cholecalciferol, and their metabolites by a category approach[J]. Drug and Chemical Toxicology, 2021, 44(6): 661-667.
[2] NEWMAN M S, BRANDON T R, GROVES M N, et al. A liquid chromatography/tandem mass spectrometry method for determination of 25-hydroxy vitamin D2 and 25-hydroxy vitamin D3 in dried blood spots: a potential adjunct to diabetes and cardiometabolic risk screening[J]. Journal of Diabetes Science and Technology, 2009, 3(1): 156-162.
[3] ADAMS J S, SHIEH A, BISHOP C W. Calcifediol as a therapeutic[M]//Feldman and Pike's Vitamin D. 5th ed. Cambridge: Academic Press, 2024: 457-474.
[4] JIN Z, BERTHOLF R L, YI X. Advances and challenges in the measurement of 1, 25-dihydroxyvitamin D: A comprehensive review[J]. Critical Reviews in Clinical Laboratory Sciences, 2023, 60(7): 535-548.
[5] HUGHES M R, BAYLINK D J, JONES P G, et al. Radioligand receptor assay for 25-hydroxyvitamin D2/D3 and 1 alpha, 25-dihydroxyvitamin D2/D3[J]. The Journal of Clinical Investigation, 1976, 58(1): 61-70.
Ercalcidiol是一种可反映体内维生素D营养水平的维生素D2代谢物[1]。Ercalcidiol较维生素D3代谢物半衰期更短，且与维生素D结合蛋白的结合力低于维生素D3，Ercalcidiol较弱的效力在用于治疗时需要更高的剂量[2]。Ercalcidiol通常用于维生素D2治疗效果的监测以及钙磷稳态障碍的治疗[3,4]。
在体外，Ercalcidiol（292.5nM）作为底物在佝偻病鸡肾脏匀浆系统中孵育2h，成功被1α-羟化酶代谢，生成了1α,25-(OH)2D2[5]。