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Miner Electrolyte Metab. 1985;11(1):5-13.
Effect of low doses of stable strontium on bone
metabolism in rats.
, Garba MT
, Hott M
, Miravet L
The effects of low doses of oral stable strontium (0.19-0.40% of
) on mineral and bone metabolism were examined in
normal rats using biochemical and histomorphometrical methods.
The strontium levels in serum and bone rose according to the intake of the
element. Oral strontium supplementation did not produce deleterious
effects on body growth or on mineral homeostasis except a transitory
slight decrease in serum calcium. At the dosage level of 0.40% however,
strontium induced a slight defective bone mineralization. At lower levels,
treated rats showed stimulated bone formation evidenced by increased
amount of osteoid and increased extent of tetracycline double-labelled
surface while the mineralization lag time remained normal.
The osteoclastic surface and the number of acid phosphatase-stained
chondroclasts and osteoclasts remained unchanged. Stimulation of bone
formation without apparent change in bone resorption resulted in a 10%
increase in the trabecular calcified bone volume.
The strontium-induced increased osteogenesis was not associated with
changes in circulating levels of 1,25(OH)2 vitamin D or in parathyroid
The results show that small doses of oral strontium may stimulate
bone formation without altering bone resorption in the rat.
PMID: 3974537 [PubMed - indexed for MEDLINE]
Short-term effects of fluoride and strontium on bone
formation and resorption in the mouse.
, Hott M
The early effects of sodium fluoride (0.80 mg/kg/d) and strontium chloride
(0.27%) given alone, or in combination in drinking water, on bone metabo lism
were examined in the mouse using dynamic histomorphometric methods.
Four weeks of oral strontium supplementation increased the osteoid surface and
reduced the number of acid phosphatase-stained osteoclasts. However the
trabecular calcified bone volume was not augmented. By contrast, short-term
treatment with fluoride produced a rapid stimulatory effect on bone formation at
a dose that did not affect the bone mineralization rate. Four weeks of fluoride
supplementation induced a rapid 21.1% increase in the osteoblastic surface and
a 26.3% stimulation of the bone matrix apposition rate evaluated by the double
tritiated proline labelling method, which resulted in a 29% increase in the
This rapid stimulation of the bone formation rate without detectable change in
osteoclastic bone resorption led to a 12% increase in the trabecular calcified
This study shows that fluoride and strontium produce distinct early
effects on bone formation and resorption in the mouse
and that fluoride
exerts a rapid stimulatory effect on the bone matrix synthesis rate through an
augmentation of the number of bone-forming cells.
PMID: 3713515 [PubMed - indexed for MEDLINE]
Effects of low doses of strontium on bone quality and
quantity in rats.
, Marie PJ
Mount Sinai Research Institute, Toronto, Canada.
Strontium (Sr) has been shown to increase bone mass when given at low doses.
In this study, the diets of rats containing 0.50% calcium were supplemented with
Sr (0.19 and 0.40% of SrCl2 orally) for periods of four and eight weeks.
Long bones and vertebrae were studied by density fractionation and each
fraction was analyzed chemically. X-ray diffraction was used to determine crystal
size. Static and dynamic histomorphometric parameters of bone formation were
also measured. We found a shift towards lower density in the mineralization
profiles of Sr supplemented rats (0.40%), as well as a decrease in bone crystal
size at the larger dose of Sr. The CO3 content and the Ca/Sr ratio of the bone
We found an increase in the vertebral trabecular bone volume together with an
increase in osteoid volume in Sr supplemented rats.
This study shows that Sr at the larger dose induces bone
hypomineralization as well as an increase in bone mass in rats
PMID: 2252809 [PubMed - indexed for MEDLINE]
J Bone Miner Res. 1993
An uncoupling agent containing strontium prevents bone
loss by depressing bone resorption and maintaining bone
formation in estrogen-deficient rats.
, Hott M
, Modrowski D
, De Pollak C
, Guillemain J
, Deloffre P
INSERM Unité 349, Hôpital Lariboisière, Paris, France.
Trabecular bone loss in estrogen deficiency is associated with enhanced bone
resorption with a smaller increase in bone formation. We previously reported that
low doses of strontium can increase trabecular bone volume in rodents by
affecting bone resorption and formation.
In this study we determined the effect of a new divalent strontium salt
on bone loss induced by E2 deficiency. Sprague-Dawley female rats
(230 g, n = 15-25 per group) were sham operated or ovariectomized (OVX) and
treated with 17 beta-estradiol (E2, 10 micrograms/kg/day, sc) or S12911 by
gavage at the dose of 77, 154, or 308 mg/kg/day or the vehicle.
Treatment for 60 days with S12911 resulted in a dose-dependent increase in
plasma, urine, and bone strontium concentrations without any deleterious effect
on total or skeletal growth. OVX rats were osteopenic compared to sham rats as
shown by decreased femoral dry bone weight and mineral content measured on
bone ash and by DXA. Treatment of OVX rats with S12911 prevented bone loss
as bone ash and bone mineral content were restored to the values in sham rats.
Trabecular bone volume measured by histomorphometry on the tibial metaphysis
was decreased by 46% in OVX rats and was corrected by E2.
Treatment of OVX rats with S12911 increased the trabecular bone
by 30-36%. Histomorphometric indices of bone resorption (osteoclast
surface and number) were increased in OVX rats and were reduced by S12911 to
the levels in sham rats.(ABSTRACT TRUNCATED AT 250 WORDS)
PMID: 8511988 [PubMed - indexed for MEDLINE]
Strontium increases vertebral bone volume in rats at a
low dose that does not induce detectable mineralization
, Hamilton E
, Cheung R
, Tsouderos Y
, Deloffre P
, Hott M
, Marie PJ
Department of Pathology, University of Toronto, Canada.
Low doses of strontium and fluoride were shown to increase bone formation and
trabecular bone density in rodents. To assess whether strontium or fluoride affect
the quality of the mineral at doses known to increase bone density, we have
determined the effects of low doses of strontium and fluoride on bone formation
and bone mineral characteristics in rats.
Adult rats were given strontium alone (0.20%), fluoride alone (1 mg/kg per
day), or the combined treatment for 8 weeks. Strontium levels in serum and
femur were similar in groups treated with strontium alone or in combination,
Biochemical and neutron activation analyses in femur showed that calcium and
magnesium contents did not differ in the four group of rats, suggesting that
strontium was incorporated in the apatite lattice of the bone minerals in the
The mineralized bone volume was significantly increased by 17%
strontium-treated group, by 20% in the fluoride-treated group
, and by 19%
in rats given with the combined treatment
. This was associated with
increased osteoid surface, osteoblast surface, and double tetracycline labeled
surfaces in the strontium-treated and fluoride-treated groups, showing that the
number of bone forming sites was increased.
However, the mineral apposition rate, the osteoid thickness, and the
mineralization lag time were similar in controls and treated groups, reflecting the
lack of deleterious effects of low doses of strontium and fluoride on bone
The density fractionation analysis measured in the femur also showed that
neither strontium, nor fluoride at the low doses used, significantly
altered the mineralization profile.
The results indicate that treatment with low doses of strontium or fluoride
increase the number of bone forming sites and vertebral bone volume in
, but does not have detectable adverse effects
on the mineral profile,
bone mineral chemistry or bone matrix mineralization.
PMID: 8703581 [PubMed - indexed for MEDLINE]
CURRICULUM VITAE Starkenborglaan 6, 2341 BM, Oegstgeest, The Netherlands Telephone d . firstname.lastname@example.org Birthplace Date of Birth Marital Status Nationality EDUCATION Elementary School High School University University Leiden, The Netherlands, 1978-1983 Specializations Biochemistry, Physical Chemistry, Immunology, During specializations 3 publication
Evidence Based Medicine My patient has a lot of variability in his blood pressure measurements? Should I be worried? What can I do which may be better? Stroke Service and Vascular Fellowship Program, International Cerebrovascular Translational Clinical Research Training Program(Fogarty International Center and National Institute of Neurologic Disorders and Stroke), Aga Khan University Ho