Calcium sensing receptor-dependent and receptor-independent activation of osteoblast replication and survival by strontium ranelate.

Age-related osteopenia is characterized by a negative balance between bone resorption and formation. The anti-osteoporotic drug strontium ranelate was found to reduce bone resorption and to promote bone formation. Here, we investigated the implication of the calcium-sensing receptor (CaSR) in the response to strontium ranelate using osteoblasts from CaSR knockout [CaSR(-/-)] and wild-type [CaSR(+/+)] mice.

FGFR2-Cbl interaction in lipid rafts triggers attenuation of PI3K/Akt signaling and osteoblast survival.

Fibroblast growth factor receptor (FGFR) signaling plays an important role in skeletogenesis. The molecular mechanisms triggered by activated FGFR in bone forming cells are however not fully understood. In this study, we identify a role for phosphatidylinositol 3-kinase (PI3K) signaling in cell apoptosis induced by FGFR2 activation in osteoblasts.

Sclerosing bone disorders.

Sclerosing bone disorders are a diagnostic challenge. However, hereditary sclerosing disorders often have characteristic radiological features that allow their diagnosis. Osteocondensation can result from decreased bone resorption; malignant recessive osteopetroses have been related to mutations in several genes necessary for osteoclast function and also, more recently, to osteoclast differentiation (RANK-L).

Strontium ranelate: a dual mode of action rebalancing bone turnover in favour of bone formation.

The increased bone remodeling in women after menopause induces an imbalance between bone resorption and formation, leading to decreased bone mass, altered bone microarchitecture, and increased fracture risk. Current antiosteoporotic drugs decrease bone remodeling or increase bone formation. Strontium ranelate (Protelos) is a newly developed antiosteoporotic drug that acts by reducing bone resorption and promoting bone formation, thereby inducing a positive bone balance.

Strontium ranelate: a physiological approach for optimizing bone formation and resorption.

Osteoporosis associated with estrogen deficiency results from an imbalance between bone resorption and formation, causing deterioration of bone architecture and decreased bone mass. Anti-osteoporotic therapies that have been developed so far include either anticatabolic or anabolic drugs. Strontium ranelate is a newly developed drug that induces opposite effects on bone resorption and formation.

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.