ABSTRACT
S trontium (Sr) has been very recently hyped as the latest “paradigm-changing” thing in the treatmen o f osteoporosis as indicated by the tide o f a paper by Reginster et al (2003)— “Strontium R anelate: A N ew parad igm fo r the treatm ent o f Osteoporosis". W hen two atoms o f strontium combine with ranelic acid, they form strontium ranelate, Sr-ranelate, that effec tively stimulates the proliferation o f fibroblasts and pre-osteoblasts from fetal Sprague-Dawley rat calvaria and less effectively the proliferation o f mature osteoblasts from these tissues. (But o f course this should have been expected because as we have learned mature osteoblasts can’t proliferate-they are terminally differentiated.) Neither Ca-ranelate nor ranelic acid alone can mimic the effects o f Sr-ranelate on these culured rat cells (Marie, 20 0 6 ; Reginster et al., 2003). Sr-ranelate, also inhibits osteoclast activity on culture models without killing the cells or their ability to attach to bone (Reginster et al., 2003). Again neither Ca-ranelate nor ranelic acid alone mimicked Sr-ranelate. Thus, the stimulation o f osteoblast precursor proliferation and the inhibition o f osteoclast activity are specific for Sr-ranelate.
