Strontium depth distribution in human bone measured by micro‐PIXE

Abstract

Strontium is naturally present in human bone, where it may exert beneficial or detrimental health effects depending on its concentration. The way strontium influences bone health and the concentrations at which the beneficial/detrimental health effects of strontium become important are still unknown, due partly to the difficulty of assessing the bone strontium concentration in vivo non-invasively. An x-ray fluorescence (XRF) system was developed, which is capable of measuring normal bone strontium levels in vivo non-invasively and therefore has the potential of becoming an important tool to understand bone strontium health effects. This technique, however, has the limitation that it relies on assumptions about bone strontium distribution to obtain a quantitative strontium measurement. To understand, to which degree, if any, the bone strontium distribution in bone changes from person to person, the bone strontium depth distribution was explored using micro-PIXE in five ex vivo cadaver fingers, taken from normal people exposed to strontium only through diet. We found that, in the measured samples, strontium was uniformly distributed across the cortical and trabecular bone, and therefore corrections do not need to be applied to in vivo strontium XRF data to correct for strontium depth distribution.

87Sr Solid-State NMR as a Structurally Sensitive Tool for the Investigation of Materials: Antiosteoporotic Pharmaceuticals and Bioactive Glasses

“…In this context, strontium is an element which is finding increasing interest, because it is now clearly established that strontium is beneficial in bone remodeling. Strontium is a naturally occurring trace element, and as a bone seeker (like calcium), ∼99% of strontium present in the body accumulates in bone. , The absorption of pharmacological doses of strontium has been associated with strengthening of bone, with the stimulation of bone formation and the decrease in bone resorption, and without affecting adversely bone mineralization. , Large randomized studies demonstrated that strontium supplements such as strontium ranelate (Protelos, Servier Laboratories, France) or strontium malonate (NB S101, Osteologix) decrease the risk of vertebral and nonvertebral fractures in women affected by postmenopausal osteoporosis, showing promise for strontium as a therapeutic agent in the treatment of osteoporosis. ,, Marked stimulatory effects of strontium ions on bone cells have also been evidenced, with enhanced osteoblast differentiation and alkaline phosphatase activity. − …”

Determining elemental strontium distribution in rat bones treated with strontium ranelate and strontium citrate using 2D micro‐XRF and 3D dual energy K‐edge subtraction synchrotron imaging

“…[8,9,13,33] Minimal research has been conducted into the ability of other strontium salts in providing similar health benefits as strontium ranelate. [34] To date, the work of our group is the first study exploring the distribution of elemental strontium F I G U R E 2 Cross-sections of the 3D elemental strontium maps of rat bones treated with (a) strontium ranelate, (b) strontium citrate, (c) and control (nontreated). Images (a) through (c) depict the epiphyseal plate within the head of each proximal humerus F I G U R E 3 An elemental strontium map of the medial portion (shaft) of one the strontium ranelate samples in bones obtained from an animal study involving the administration of strontium ranelate and an alternative strontium salt, strontium citrate.…”

“…It has been shown that strontium ranelate is capable of improving intrinsic bone tissue quality of osteoporotic bone and reducing the risk of fractures associated with the disease in various animal models as well as in humans . Minimal research has been conducted into the ability of other strontium salts in providing similar health benefits as strontium ranelate . To date, the work of our group is the first study exploring the distribution of elemental strontium in bones obtained from an animal study involving the administration of strontium ranelate and an alternative strontium salt, strontium citrate.…”

Atomic spectrometry update. Clinical and biological materials, foods and beverages

“…However, one new piece of work, in which micro-PIXE was employed, was seen. 86 The technique was applied to analysis of bone for Sr, as an approach to investigate bone health. 4.5.2 XRF for surface analysis and imaging.…”

“…In developing their benchtop XRF instrument, Bellis et al 91 found a heterogeneous distribution of Pb and Sr in bone. Zamburlini et al 86 also examined how Sr was distributed through bone using a micro-PIXE system. Their work, with cadaver fingers indicated a uniform concentration of Sr throughout bone.…”