Biosynthesis Of Active Form Of Vitamin D
Calcitriol circulates as a hormone in the blood having a major role regulating the concentration of calcium and phosphate and promoting the healthy growth and remodeling of bone. Before the molecule of vitamin d acts in the control of calcium metabolism it is converted to a functional form in at least two metabolic steps.
Vitamin D Production Metabolism And Mechanisms Of Action
Vitamin d any of a group of fat soluble vitamins important in calcium metabolism in animals.
Biosynthesis of active form of vitamin d. This transformation occurs in two steps as depicted in the diagram to the right. The production of vitamin d is not enzymatic but depends on uvb. Calcifediol is further hydroxylated by the kidneys to form calcitriol also known as 125 dihydroxycholecalciferol the biologically active form of vitamin d.
Vitamin d whether produced in the skin from 7 dhc or absorbed from the diet must be activated first to 25ohd and then to its active form 125oh 2 d. Vitamin d as either d 3 or d 2 does not have significant biological activity. Vitamin d is transported in the blood by the.
It is formed by ultraviolet radiation sunlight of sterols present in the skin. The first a side chain hydroxylation at carbon 25. In order to be biologically active and affect mineral metabolism and to have effects on numerous other diverse physiological functions including inhibition of growth of cancer cells and protection against certain immune mediated disorders vitamin d most be converted to its active form 4 5.
It is subsequently metabolized to its hormonally active form 125 dihydroxyvitamin d 125oh2d by the 1 hydroxylase and catabolized by the 24 hydroxylase. Vitamin d is produced in the skin. Calcitriol also has other effects including some on cell growth neuromuscular and immune functions and reduction of inflammation.
Rather it must be metabolized within the body to the hormonally active form known as 125 dihydroxycholecalciferol.
Vitamins Critical Enzyme Co Factors
Vitamin K Wikipedia
Oxysterols Cholesterol Sulfate Cholesterol Glycosides Vitamin D
6 Vitamins And Nutrition Functions Of Cells And Human Body
Vitamin D Metabolism
The Vitamin D Antimicrobial Peptide Pathway And Its Role In
Vitamin D Deficiency By Dr Mihir Adhikari
Vitamin D Metabolism Mechanism Of Action And Clinical
Vitamin A Wikipedia
