Abstract
Analogs of vitamin D constitute a class of pharmacological agents with calciumregulating and cell-differentiating properties. They are designed to directly or indirectly mimic the actions of the naturally occurring hormone 1α, 25-(OH)2D 3. Since this molecule is activated and inactivated by cytochrome P450-mediated hydroxylation, these steps can be circumvented or blocked in vitamin D analog and prodrug design. All natural and synthetic analogs are currently believed to work through a nuclear receptor (VDR)-mediated transactivation process which serves to regulate the expression of variety of proteins at the gene transcriptional level. There is optimism that “tweaking” the vitamin D molecule structure will provide analogs with selective actions of 1α,25-(OH)2D3 for use in dermatology, cancer, osteoporosis and immunology-related conditions.