Vitamin D receptor agonists as anti-inflammatory agents.

1alpha,25-dihydroxyvitamin D3 (1,25-[OH]2D3), the biologically active form of vitamin D, is a secosteroid hormone that is essential for bone and mineral homeostasis. In addition, this hormone regulates the growth and differentiation of many cell types and has pronounced immunoregulatory and anti-inflammatory properties. Current therapeutic indications include osteoporosis, secondary hyperparathyroidism and psoriasis, but the anti-proliferative, prodifferentiative, antibacterial, immunomodulatory and anti-inflammatory properties of vitamin D receptor agonists could be exploited in a variety of additional clinical conditions. In particular, the pleiotropic anti-inflammatory effects induced by vitamin D receptor agonists could turn out to be beneficial in different pathologies mediated by chronic inflammatory responses.