scholarly journals Inhibition of GSK-3βincreases trabecular bone volume but not cortical bone volume in adenine-induced uremic mice with severe hyperparathyroidism

2016 ◽  
Vol 4 (21) ◽  
pp. e13010 ◽  
Author(s):  
Narihito Tatsumoto ◽  
Masaki Arioka ◽  
Shunsuke Yamada ◽  
Fumi Takahashi-Yanaga ◽  
Masanori Tokumoto ◽  
...  
Keyword(s):  
Trabecular Bone ◽  
Cortical Bone ◽  
Bone Volume ◽  
Trabecular Bone Volume

scholarly journals Mechanical Loading-Related Bone Gain Is Enhanced by Tamoxifen but Unaffected by Fulvestrant in Female Mice

Endocrinology ◽  
2010 ◽  
Vol 151 (12) ◽  
pp. 5582-5590 ◽  
Author(s):  
Toshihiro Sugiyama ◽  
Gabriel L. Galea ◽  
Lance E. Lanyon ◽  
Joanna S. Price
Keyword(s):  
Trabecular Bone ◽  
Cortical Bone ◽  
Mechanical Loading ◽  
Bone Volume ◽  
Trabecular Bone Volume ◽  
Trabecular Thickness ◽  
Female Mice ◽  
Short Period ◽  
Bone Gain ◽  
The Right

Accumulating evidence indicates that estrogen receptors (ERs) are involved in the mechano-adaptive mechanisms by which loading influences the mass and architecture of bones to establish and maintain their structural load-bearing competence. In the present study, we assessed the effects of the ER modulators tamoxifen and fulvestrant (ICI 182,780) on loading-related changes in the volume and structure of trabecular and cortical bone in the tibiae of female mice. Ten days after actual or sham ovariectomy, 17-wk-old female C57BL/6 mice were treated with vehicle (peanut oil), tamoxifen (0.02, 0.2, or 2 mg/kg · d), fulvestrant (4 mg/kg · d), or their combination and the right tibiae subjected to a short period of noninvasive axial loading (40 cycles/d) on 5 d during the subsequent 2 wk. In the left control tibiae, ovariectomy, tamoxifen, or fulvestrant did not have any significant effect on cortical bone volume, whereas trabecular bone volume was decreased by ovariectomy, increased by tamoxifen, and unaffected by fulvestrant. In the right tibiae, loading was associated with increases in both trabecular and cortical bone volume. Notably, the medium dose of tamoxifen synergistically enhanced loading-related gain in trabecular bone volume through an increase in trabecular thickness. Fulvestrant had no influence on the effects of loading but abrogated the enhancement of loading-related bone gain by tamoxifen. These data demonstrate that, at least in female mice, the adaptive response to mechanical loading of trabecular bone can be enhanced by ER modulators, in this case by tamoxifen.

scholarly journals Trabecular bone volume and osteoprotegerin expression in uremic rats given high calcium

2010 ◽  
Vol 25 (11) ◽  
pp. 2311-2319 ◽  
Author(s):  
Pornpimol Rianthavorn ◽  
Robert B. Ettenger ◽  
Isidro B. Salusky ◽  
Beatriz D. Kuizon
Keyword(s):  
Trabecular Bone ◽  
Bone Volume ◽  
Trabecular Bone Volume ◽  
High Calcium

scholarly journals Bone health in spacefaring rodents and primates: systematic review and meta-analysis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jingyan Fu ◽  
Matthew Goldsmith ◽  
Sequoia D. Crooks ◽  
Sean F. Condon ◽  
Martin Morris ◽  
...  
Keyword(s):  
Bone Formation ◽  
Trabecular Bone ◽  
Bone Health ◽  
Volume Fraction ◽  
Meta Analysis ◽  
Bone Volume ◽  
Trabecular Bone Volume ◽  
Bone Volume Fraction ◽  
Percentage Difference ◽  
Induced Changes

AbstractAnimals in space exploration studies serve both as a model for human physiology and as a means to understand the physiological effects of microgravity. To quantify the microgravity-induced changes to bone health in animals, we systematically searched Medline, Embase, Web of Science, BIOSIS, and NASA Technical reports. We selected 40 papers focusing on the bone health of 95 rats, 61 mice, and 9 rhesus monkeys from 22 space missions. The percentage difference from ground control in rodents was –24.1% [Confidence interval: −43.4, −4.9] for trabecular bone volume fraction and –5.9% [−8.0, −3.8] for the cortical area. In primates, trabecular bone volume fraction was lower by –25.2% [−35.6, −14.7] in spaceflight animals compared to GC. Bone formation indices in rodent trabecular and cortical bone were significantly lower in microgravity. In contrast, osteoclast numbers were not affected in rats and were variably affected in mice. Thus, microgravity induces bone deficits in rodents and primates likely through the suppression of bone formation.

scholarly journals Prolyl Hydroxylase Domain-Containing Protein 3 Gene Expression in Chondrocytes Is Not Essential for Bone Development in Mice

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2200
Author(s):  
Weirong Xing ◽  
Sheila Pourteymoor ◽  
Gustavo A. Gomez ◽  
Yian Chen ◽  
Subburaman Mohan
Keyword(s):  
Gene Expression ◽  
Bone Formation ◽  
Bone Mass ◽  
Trabecular Bone ◽  
Bone Volume ◽  
Endochondral Bone Formation ◽  
Chondrocyte Differentiation ◽  
Trabecular Bone Volume ◽  
Endochondral Bone ◽  
Trabecular Bone Mass

We previously showed that conditional disruption of the Phd2 gene in chondrocytes led to a massive increase in long bone trabecular bone mass. Loss of Phd2 gene expression or inhibition of PHD2 activity by a specific inhibitor resulted in a several-fold compensatory increase in Phd3 expression in chondrocytes. To determine if expression of PHD3 plays a role in endochondral bone formation, we conditionally disrupted the Phd3 gene in chondrocytes by crossing Phd3 floxed (Phd3flox/flox) mice with Col2α1-Cre mice. Loss of Phd3 expression in the chondrocytes of Cre+; Phd3flox/flox conditional knockout (cKO) mice was confirmed by real time PCR. At 16 weeks of age, neither body weight nor body length was significantly different in the Phd3 cKO mice compared to Cre−; Phd3flox/flox wild-type (WT) mice. Areal BMD measurements of total body as well as femur, tibia, and lumbar skeletal sites were not significantly different between the cKO and WT mice at 16 weeks of age. Micro-CT measurements revealed significant gender differences in the trabecular bone volume adjusted for tissue volume at the secondary spongiosa of the femur and the tibia for both genotypes, but no genotype difference was found for any of the trabecular bone measurements of either the femur or the tibia. Trabecular bone volume of distal femur epiphysis was not different between cKO and WT mice. Histology analyses revealed Phd3 cKO mice exhibited a comparable chondrocyte differentiation and proliferation, as evidenced by no changes in cartilage thickness and area in the cKO mice as compared to WT littermates. Consistent with the in vivo data, lentiviral shRNA-mediated knockdown of Phd3 expression in chondrocytes did not affect the expression of markers of chondrocyte differentiation (Col2, Col10, Acan, Sox9). Our study found that Phd2 but not Phd3 expressed in chondrocytes regulates endochondral bone formation, and the compensatory increase in Phd3 expression in the chondrocytes of Phd2 cKO mice is not the cause for increased trabecular bone mass in Phd2 cKO mice.

Bone Formation and Resorption as the Determinants of Trabecular Bone Volume in Normal and Osteoporotic Men

1984 ◽  
Vol 29 (3) ◽  
pp. 171-175 ◽  
Author(s):  
B. E. C. Nordin ◽  
J. Aaron ◽  
R. Speed ◽  
R. M. Francis ◽  
N. Makins
Keyword(s):  
Bone Formation ◽  
Trabecular Bone ◽  
Inverse Function ◽  
Positive Function ◽  
Bone Volume ◽  
Trabecular Bone Volume ◽  
Age Related ◽  
Osteoporosis In Men ◽  
Spinal Osteoporosis ◽  
The Mean

Trabecular bone volume, forming surface and percent surface resorption have been determined in iliac crest samples obtained post mortem from 43 young men and 49 elderly men and in biopsies obtained from 22 males with spinal osteoporosis. The mean bone volume was significantly lower in the old than in the young controls and significantly lower again in the osteoporotic cases. Forming surfaces were significantly lower in the old than the young controls but were not different as between old controls and cases of osteoporosis. Percent surface resorption was the same in young and old controls but significantly increased in the osteoporotics. Multiple regression analysis showed that trabecular bone volume was a significant positive function of forming surface and a significant inverse function of fractional surface resorption. Age-related (simple) osteoporosis in men appears to be due to reduced bone formation whereas pathological (accelerated) osteoporosis is due to increased bone resorption.

scholarly journals Glucose-dependent insulinotropic polypeptide receptor deficiency leads to modifications of trabecular bone volume and quality in mice

Bone ◽  
2013 ◽  
Vol 53 (1) ◽  
pp. 221-230 ◽  
Author(s):  
Christine Gaudin-Audrain ◽  
Nigel Irwin ◽  
Sity Mansur ◽  
Peter R. Flatt ◽  
Bernard Thorens ◽  
...  
Keyword(s):  
Trabecular Bone ◽  
Bone Volume ◽  
Trabecular Bone Volume

scholarly journals Mice Lacking β-Adrenergic Receptors Have Increased Bone Mass but Are Not Protected from Deleterious Skeletal Effects of Ovariectomy

Endocrinology ◽  
2008 ◽  
Vol 150 (1) ◽  
pp. 144-152 ◽  
Author(s):  
M. L. Bouxsein ◽  
M. J. Devlin ◽  
V. Glatt ◽  
H. Dhillon ◽  
D. D. Pierroz ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Body Weight ◽  
Bone Mass ◽  
Trabecular Bone ◽  
Adrenergic Receptors ◽  
Bone Volume ◽  
Trabecular Bone Volume ◽  
Mineral Density ◽  
Adrenergic Signaling ◽  
Β Adrenergic Receptors

Activation of β2-adrenergic receptors inhibits osteoblastic bone formation and enhances osteoclastic bone resorption. Whether β-blockers inhibit ovariectomy-induced bone loss and decrease fracture risk remains controversial. To further explore the role of β-adrenergic signaling in skeletal acquisition and response to estrogen deficiency, we evaluated mice lacking the three known β-adrenergic receptors (β-less). Body weight, percent fat, and bone mineral density were significantly higher in male β-less than wild-type (WT) mice, more so with increasing age. Consistent with their greater fat mass, serum leptin was significantly higher in β-less than WT mice. Mid-femoral cross-sectional area and cortical thickness were significantly higher in adult β-less than WT mice, as were femoral biomechanical properties (+28 to +49%, P < 0.01). Young male β-less had higher vertebral (1.3-fold) and distal femoral (3.5-fold) trabecular bone volume than WT (P < 0.001 for both) and lower osteoclast surface. With aging, these differences lessened, with histological evidence of increased osteoclast surface and decreased bone formation rate at the distal femur in β-less vs. WT mice. Serum tartrate-resistance alkaline phosphatase-5B was elevated in β-less compared with WT mice from 8–16 wk of age (P < 0.01). Ovariectomy inhibited bone mass gain and decreased trabecular bone volume/total volume similarly in β-less and WT mice. Altogether, these data indicate that absence of β-adrenergic signaling results in obesity and increased cortical bone mass in males but does not prevent deleterious effects of estrogen deficiency on trabecular bone microarchitecture. Our findings also suggest direct positive effects of weight and/or leptin on bone turnover and cortical bone structure, independent of adrenergic signaling. Mice lacking ß-adrenergic receptors have increased body weight, bone mineral density, and bone turnover versus controls, but are not protected from bone loss due to deficiency of estrogens..

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