Biochem/physiol Actions Cholecalciferol is an inactive form of vitamin D3 which undergoes various levels of hydroxylation to form active vitamin D3 analogs. 1α-Hydroxyvitamin D3 (alfacalcidol) is a synthetic analog that is metabolized to 1,25-dihydroxycholecalciferol, the biologically active form of vitamin D3. Other analogues of cholecalciferol result from different hydroxylations. 24R,25-Dihydroxyvitamin D3 is a catabolite of 25-Dihydroxyvitamin D3 and a putative regulator of developmental bone formation. 24R,25-Dihydroxyvitamin D3 is a substrate for renal 25-hydroxyvitamin D3 1 α-hydroxylase. 24R,25-Dihydroxyvitamin D3 is an endogenous regulator of apo A-I synthesis through a VDR-independent signaling mechanism and an inhibitor of Pi-induced apoptosis through Ca2+, PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation. |
Biochem/physiol Actions Cholecalciferol is an inactive form of vitamin D3 which undergoes various levels of hydroxylation to form active vitamin D3 analogs. 1α-Hydroxyvitamin D3 (alfacalcidol) is a synthetic analog that is metabolized to 1,25-dihydroxycholecalciferol, the biologically active form of vitamin D3. Other analogues of cholecalciferol result from different hydroxylations. 24R,25-Dihydroxyvitamin D3 is a catabolite of 25-Dihydroxyvitamin D3 and a putative regulator of developmental bone formation. 24R,25-Dihydroxyvitamin D3 is a substrate for renal 25-hydroxyvitamin D3 1 α-hydroxylase. 24R,25-Dihydroxyvitamin D3 is an endogenous regulator of apo A-I synthesis through a VDR-independent signaling mechanism and an inhibitor of Pi-induced apoptosis through Ca2+, PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation. |