A report on Ergocalciferol and CYP2R1

Conversion of cholecalciferol to calcidiol as catalyzed by CYP2R1.
Vitamin D2 supplements

CYP2R1 will also hydroxylate ergocalciferol (vitamin D2), derived from dietary sources, into 25-hydroxyvitamin D2 (ercalcidiol).

- CYP2R1

It requires two hydroxylations to become active: the first in the liver by CYP2R1 to form 25-hydroxyergocalciferol (ercalcidiol or 25-OH D2 ), and the second in the kidney by CYP27B1, to form the active 1,25-dihydroxyergocalciferol (ercalcitriol or 1,25-(OH)2D2), which activates the vitamin D receptor.

- Ergocalciferol

2 related topics with Alpha

Overall

Cholecalciferol (D3)

Vitamin D

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Group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects.

Group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects.

Cholecalciferol (D3)
Calcium regulation in the human body. The role of active vitamin D (1,25-dihydroxyvitamin D, calcitriol) is shown in orange.
Global vitamin D serum levels among adults (nmol/L).
The photochemistry of vitamin D biosynthesis in animal and fungi
Thermal isomerization of previtaminD3 to vitamin D3
In the epidermal strata of the skin, vitamin D production is greatest in the stratum basale (colored red in the illustration) and stratum spinosum (colored light brown).
Liver hydroxylation of cholecalciferol to calcifediol
Kidney hydroxylation of calcifediol to calcitriol

In humans, the most important compounds in this group are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol).

This reaction is catalyzed by the microsomal enzyme vitamin D 25-hydroxylase, the product of the CYP2R1 human gene, and expressed by hepatocytes.

Cholecalciferol

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Type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement.

Type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement.

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There are conflicting reports concerning the relative effectiveness of cholecalciferol (D3) versus ergocalciferol (D2), with some studies suggesting less efficacy of D2, and others showing no difference.

It is converted to its active form by two hydroxylations: the first in the liver, by CYP2R1 or CYP27A1, to form 25-hydroxycholecalciferol (calcifediol, 25-OH vitamin D3).