Strontium as therapy for osteoporosis.

Osteoporosis is characterized by low bone mass and increased susceptibility to fracture. Recent in vitro studies showed that strontium ranelate, a novel agent containing two strontium atoms, acts as an effective anti-osteoporotic drug by inhibiting bone resorption by osteoclasts and promoting osteoblast replication and bone formation. Studies in animals demonstrated that strontium ranelate increases bone mass, microarchitecture and strength in intact rodents and prevents bone loss in osteopenic animals. Clinical studies show that strontium ranelate reduces the risk of vertebral and non-vertebral fractures in postmenopausal osteoporosis. Together, these recent advances point to unique effects of strontium ranelate on bone cells and show that strontium ranelate has significant clinical benefits in the treatment of postmenopausal osteoporosis.