scholarly journals Sweep imaging with Fourier transform as a tool with MRI for evaluating the effect of teriparatide on cortical bone formation in an ovariectomized rat model

2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Yasutaka Sotozono ◽  
Kazuya Ikoma ◽  
Masamitsu Kido ◽  
Okihiro Onishi ◽  
Masataka Minami ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Bone Formation ◽  
Cortical Bone ◽  
Bone Histomorphometry ◽  
Signal To Noise Ratio ◽  
Formation Rate ◽  
Bound Water ◽  
Proton Density ◽  
Sprague Dawley ◽  
Bone Formation Rate

Abstract Background Teriparatide (TPTD) is a drug for osteoporosis that promotes bone formation and improves bone quality. However, the effects of TPTD on cortical bone are not well understood. Sweep imaging with Fourier transform (SWIFT) has been reported as a useful tool for evaluating bound water of cortical bone, but it has yet to be used to investigate the effects of TPTD on cortical bone. This study aimed to evaluate the consequences of the effect of TPTD on cortical bone formation using SWIFT. Methods Twelve-week-old female Sprague-Dawley rats (n = 36) were reared after ovariectomy to create a postmenopausal osteoporosis model. They were divided into two groups: the TPTD and non-TPTD groups. Rats were euthanized at 4, 12, and 24 weeks after initiating TPTD treatment. Tibial bones were evaluated using magnetic resonance imaging (MRI) and bone histomorphometry. In MRI, proton density-weighted imaging (PDWI) and SWIFT imaging were performed. The signal-to-noise ratio (SNR) was calculated for each method. The same area evaluated by MRI was then used to calculate the bone formation rate by bone histomorphometry. Measurements were compared using the Mann-Whitney U-test, and a P-value of < 0.05 was considered significant. Results PDWI-SNR was not significantly different between the two groups at any time point (P = 0.589, 0.394, and 0.394 at 4, 12, and 24 weeks, respectively). Contrarily, SWIFT-SNR was significantly higher in the TPTD group than in the non-TPTD group at 4 weeks after initiating treatment, but it was not significantly different at 12 and 24 weeks (P = 0.009, 0.937, and 0.818 at 4, 12, and 24 weeks, respectively). The bone formation rate assessed by histomorphometry was significantly higher in the TPTD group than in the non-TPTD group at all timepoints (P < 0.05, all weeks). In particular, at 4 weeks, the bone formation rate was markedly higher in the TPTD group than in the non-TPTD group (P = 0.028, 1.98 ± 0.33 vs. 0.09 ± 0.05 μm3/μm2/day). Conclusions SWIFT could detect increased signals of bound water, reflecting the effect of TPTD on the cortical bone. The signal detected by SWIFT reflects a marked increase in the cortical bone formation rate.

scholarly journals Sweep Imaging with Fourier Transform as a Tool for Evaluating the Effect of Teriparatide on Cortical Bone Turnover in an Ovariectomized Rat Model

2021 ◽  
Author(s):  
Sotozono Yasutaka ◽  
Kazuya Ikoma ◽  
Masamitsu Kido ◽  
Okihiro Onishi ◽  
Masataka Minami ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Bone Formation ◽  
Bone Turnover ◽  
Cortical Bone ◽  
Bone Histomorphometry ◽  
Signal To Noise Ratio ◽  
Formation Rate ◽  
Proton Density ◽  
Sprague Dawley ◽  
Bone Formation Rate

Abstract Background: Teriparatide (TPTD) is a drug for osteoporosis that promotes bone formation and improves bone turnover. However, the specific effects of TPTD on cortical bone are not well understood. Sweep imaging with Fourier transform (SWIFT) has been reported as a useful tool for evaluating cortical bone, but it has yet to be used to investigate the effects of TPTD on cortical bone. This study aimed to evaluate the effects of TPTD on cortical bone turnover using SWIFT in rats. Methods: Twelve-week-old female Sprague-Dawley rats (n=36) were reared for 12 weeks after ovariectomy to create a postmenopausal osteoporosis model. They were divided into two groups: the TPTD and non-TPTD groups. Rats were euthanized at 4, 12, and 24 weeks after initiating TPTD treatment. Tibial bones were extracted and evaluated using magnetic resonance imaging (MRI) and bone histomorphometry. In MRI, proton density-weighted imaging (PDWI) and SWIFT imaging were performed. The signal-to-noise ratio (SNR) was calculated for each method. The same area evaluated by MRI was then used to calculate for the bone formation rate by bone histomorphometry . Measurements were compared using the Mann-Whitney U-test, and a P-value of <0.05 was considered significant. Results: PDWI-SNR was not significantly different between the two groups at any time point (P = 0.589, 0.394, and 0.394 at 4, 12, and 24 weeks, respectively). Contrarily, SWIFT-SNR was significantly higher in the TPTD group than in the non-TPTD group at 4 weeks after initiating treatment, but it was not significantly different at 12 and 24 weeks (P = 0.009, 0.937, and 0.818 at 4, 12, and 24 weeks, respectively). The bone formation rate was significantly higher in the TPTD group than in the non-TPTD group at all timepoints (P < 0.05, all weeks). In particular, at 4 weeks, the bone formation rate was markedly higher in the TPTD group than in the non-TPTD group (1.98±0.33 vs. 0.09±0.05 μm3/μm2/day).Conclusions: The marked increase of the bone formation rate in the cortical bone by TPTD could be measured using SWIFT. SWIFT could be an effective tool for evaluating the effects of TPTD on cortical bone turnover as images.

Regulation of bone repletion in rats subjected to varying low-calcium stress

1984 ◽  
Vol 246 (2) ◽  
pp. R190-R196 ◽  
Author(s):  
R. H. Drivdahl ◽  
C. C. Liu ◽  
D. J. Baylink
Keyword(s):  
Bone Formation ◽  
Formation Rate ◽  
Bone Volume ◽  
Strong Positive Correlation ◽  
Sprague Dawley ◽  
Bone Formation Rate ◽  
Osteoblast Activity ◽  
Calcium Stress ◽  
Sprague Dawley Rats ◽  
Very High

Weanling Sprague-Dawley rats subjected to varying degrees of low-Ca dietary stress (depletion) showed graded increases in the rate of endosteal bone formation when normal dietary Ca was restored (repletion). There was a strong positive correlation between the rate of bone resorption in depletion and the rate of bone formation attained after 1 wk of repletion. However, bone formation declined rapidly within the first 4 wk of repletion, despite the persistence of a substantial endosteal bone volume deficit. Furthermore the medullary area (indicative of bone volume) did not by itself determine the bone formation rate. Bone volume in test groups was restored to control levels after 6 mo of repletion, and this result could be predicted by a kinetic analysis. Thus, although very high rates of formation in early repletion decline rapidly, smaller increments relative to controls must be sustained for long periods. Our data indicate that increased formation rats at all stages of repletion are a consequence of elevations in both osteoblast number and osteoblast activity.

scholarly journals Bone microstructural defects and osteopenia in hemizygous βIVSII-654knockin thalassemic mice: sex-dependent changes in bone density and osteoclast function

2015 ◽  
Vol 309 (11) ◽  
pp. E936-E948 ◽  
Author(s):  
Kanogwun Thongchote ◽  
Saovaros Svasti ◽  
Jarinthorn Teerapornpuntakit ◽  
Panan Suntornsaratoon ◽  
Nateetip Krishnamra ◽  
...  
Keyword(s):  
Bone Formation ◽  
Bone Histomorphometry ◽  
Formation Rate ◽  
Computer Assisted ◽  
Mineral Density ◽  
Bone Formation Rate ◽  
Male And Female ◽  
Female Mice ◽  
Growing Period ◽  
Microstructural Defects

β-Thalassemia, a hereditary anemic disorder, is often associated with skeletal complications that can be found in both males and females. The present study aimed to investigate the age- and sex-dependent changes in bone mineral density (BMD) and trabecular microstructure in βIVSII-654knockin thalassemic mice. Dual-energy X-ray absorptiometry and computer-assisted bone histomorphometry were employed to investigate temporal changes in BMD and histomorphometric parameters in male and female mice of a βIVSII-654knockin mouse model of human β-thalassemia, in which impaired splicing of β-globin transcript was caused by hemizygous C→T mutation at nucleotide 654 of intron 2. Young, growing βIVSII-654mice (1 mo old) manifested shorter bone length and lower BMD than their wild-type littermates, indicating possible growth retardation and osteopenia, the latter of which persisted until 8 mo of age (adult mice). Interestingly, two-way analysis of variance suggested an interaction between sex and βIVSII-654genotype, i.e., more severe osteopenia in adult female mice. Bone histomorphometry further suggested that low trabecular bone volume in male βIVSII-654mice, particularly during a growing period (1–2 mo), was primarily due to suppression of bone formation, whereas both a low bone formation rate and a marked increase in osteoclast surface were observed in female βIVSII-654mice. In conclusion, osteopenia and trabecular microstructural defects were present in both male and female βIVSII-654knockin thalassemic mice, but the severity, disease progression, and cellular mechanism differed between the sexes.

scholarly journals DSS-induced colitis produces inflammation-induced bone loss while irisin treatment mitigates the inflammatory state in both gut and bone

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Corinne E. Metzger ◽  
S. Anand Narayanan ◽  
Jon P. Elizondo ◽  
Anne Michal Carter ◽  
David C. Zawieja ◽  
...  
Keyword(s):  
Bone Loss ◽  
Bone Formation ◽  
Therapeutic Potential ◽  
Negative Impact ◽  
Formation Rate ◽  
Inflammatory Factors ◽  
Sprague Dawley ◽  
Mineral Density ◽  
Bone Formation Rate ◽  
Gut Inflammation

Abstract Chronic pediatric inflammatory bowel disease (IBD) leads to lack of bone accrual, bone loss, and increased fractures. Presently there is no cure, and many IBD treatments incur negative side effects. We previously discovered treatment with exogenous irisin resolved inflammatory changes in the colon, gut lymphatics, and bone in a mild IBD rodent model. Here we assess irisin treatment in severe IBD induced via dextran sodium sulfate (DSS). Male Sprague Dawley rats (2-mo-old) were untreated (Con) or given 2% DSS in drinking water. In week two, half of each group (Con + Ir and DSS + Ir) received injections of recombinant irisin (i.p., 2x/wk). After 4 weeks, gut inflammation was associated with declines in bone mineral density and cancellous bone volume. Furthermore, elevated osteocyte TNF-α, interleukin-6, RANKL, OPG, and sclerostin corresponded with higher osteoclast surfaces and lower bone formation rate in DSS animals as well as lower ultimate load. While irisin treatment improved colon inflammation, there were no improvements in bone density or bone mechanical properties; however, irisin elevated bone formation rate, decreased osteoclast surfaces, and reduced osteocyte pro-inflammatory factors. These data highlight the negative impact of chronic gut inflammation on bone as well as the therapeutic potential of irisin as an anti-inflammatory treatment.

Simulated resistance training, but not alendronate, increases cortical bone formation and suppresses sclerostin during disuse

2012 ◽  
Vol 112 (5) ◽  
pp. 918-925 ◽  
Author(s):  
B. R. Macias ◽  
J. M. Swift ◽  
M. I. Nilsson ◽  
H. A. Hogan ◽  
S. D. Bouse ◽  
...  
Keyword(s):  
Resistance Training ◽  
Bone Formation ◽  
Cortical Bone ◽  
Bone Growth ◽  
Formation Rate ◽  
Bone Geometry ◽  
Muscle Contractions ◽  
Hindlimb Unloading ◽  
Sprague Dawley ◽  
Cross Sectional

Mechanical loading modulates the osteocyte-derived protein sclerostin, a potent inhibitor of bone formation. We hypothesized that simulated resistance training (SRT), combined with alendronate (ALEN) treatment, during hindlimb unloading (HU) would most effectively mitigate disuse-induced decrements in cortical bone geometry and formation rate (BFR). Sixty male, Sprague-Dawley rats (6-mo-old) were randomly assigned to either cage control (CC), HU, HU plus either ALEN (HU+ALEN), or SRT (HU+SRT), or combined ALEN and SRT (HU+SRT/ALEN) for 28 days. Computed tomography scans on days − 1 and 28 were taken at the middiaphyseal tibia. HU+SRT and HU+SRT/ALEN rats were subjected to muscle contractions once every 3 days during HU (4 sets of 5 repetitions; 1,000 ms isometric + 1,000 ms eccentric). The HU+ALEN and HU+SRT/ALEN rats received 10 μg/kg ALEN 3 times/wk. Compared with the CC animals, HU suppressed the normal slow growth-induced increases of cortical bone mineral content, cortical bone area, and polar cross-sectional moment of inertia; however, SRT during HU restored cortical bone growth. HU suppressed middiaphyseal tibia periosteal BFR by 56% vs. CC ( P < 0.05). However, SRT during HU restored BFR at both periosteal (to 2.6-fold higher than CC) and endocortical (14-fold higher than CC) surfaces ( P < 0.01). ALEN attenuated the SRT-induced BFR gains during HU. The proportion of sclerostin-positive osteocytes in cortical bone was significantly higher (+121% vs. CC) in the HU group; SRT during HU effectively suppressed the higher proportion of sclerostin-positive osteocytes. In conclusion, a minimum number of high-intensity muscle contractions, performed during disuse, restores cortical BFR and suppress unloading-induced increases in sclerostin-positive osteocytes.

Lack of effect of spaceflight on bone mass and bone formation in group-housed rats

1998 ◽  
Vol 85 (1) ◽  
pp. 279-285 ◽  
Author(s):  
T. J. Wronski ◽  
M. Li ◽  
Y. Shen ◽  
S. C. Miller ◽  
B. M. Bowman ◽  
...  
Keyword(s):  
Bone Formation ◽  
Bone Mass ◽  
Cancellous Bone ◽  
Space Shuttle ◽  
Formation Rate ◽  
Lumbar Vertebrae ◽  
Sprague Dawley ◽  
Bone Formation Rate ◽  
Bone Changes ◽  
Space Shuttle Columbia

As part of an experiment to study the role of corticosteroids in bone changes during spaceflight, male Sprague-Dawley rats (6 wk old, 165 g body weight) were placed in orbit for 17 days, in groups of six, in animal-enclosure modules (AEMs) aboard the space shuttle Columbia (STS-78). Control rats were group housed in a similar manner in ground-based AEMs or standard vivarium cages. Adrenal hypertrophy occurred in flight rats, but bone histomorphometric analyses revealed a lack of significant changes in bone mass and bone formation in these animals. Cancellous bone volume and osteoblast surface in the proximal tibial metaphysis were nearly the same in flight and ground-based rats. Normal levels of cancellous bone mass and bone formation were also detected in the lumbar vertebrae and femoral necks of flight rats. In the tibial diaphysis, periosteal bone formation rate was found to be identical in flight and ground-based rats. The results indicate that, under conditions of group housing in AEMs, spaceflight has minimal effects on bone mass and bone formation in rapidly growing rats. These findings emphasize the need to investigate the importance of rat age, strain, and especially housing conditions for studies of the skeletal effects of spaceflight.

Human parathyroid hormone(1–34) increases bone formation and strength of cortical bone in aged rats

1994 ◽  
Vol 130 (2) ◽  
pp. 201-207 ◽  
Author(s):  
Charlotte Ejersted ◽  
Troels T Andreassen ◽  
Magnus HL Nilsson ◽  
Hans Oxlund
Keyword(s):  
Parathyroid Hormone ◽  
Bone Formation ◽  
Cortical Bone ◽  
Formation Rate ◽  
The Body ◽  
Male Rats ◽  
Double Labelling ◽  
Aged Rats ◽  
Human Parathyroid Hormone ◽  
Bone Formation Rate

Ejersted C, Andreassen TT, Nilsson MHL, Oxlund H. Human parathyroid hormone(1–34) increases bone formation and strength of cortical bone in aged rats. Eur J Endocrinol 1994;130:201–7. ISSN 0804–4643 The effect of parathyroid hormone (PTH(1–34)) on mid-diaphyseal femoral cortical bone was studied in 2-year-old male rats. The rats were treated with daily injections of 1 5 nmol/kg PTH(1–34) or vehicle for 56 days, and labelled with tetracycline and calcein on day 15 and day 40, respectively. The PTH(1–34) treatment did not affect the body weights or the lengths of the femora. Fluorescence microscopy showed large intracortical cavities in the old vehicle-treated rats. After PTH treatment, double labelling and new bone formation filling in these cavities were found. Furthermore, an increased bone formation rate was observed both at the periosteum and at the endosteum. This resulted in an increase in the cross-sectional area and a decrease in the medullary area. Three-point bending analysis revealed an increase in ultimate load, ultimate stiffness, energy absorption and ultimate stress after the PTH(1–34) treatment. No differences were found between the groups regarding the hydroxyproline concentration or apparent and real densities. The ash concentration was, however, slightly reduced after PTH(1–34) treatment. The PTH(1–34) treatment of old rats induced the formation of bone both from the periosteum and endosteum, with a pronounced filling in of intracortical cavities, and, furthermore, a marked increase in the biomechanical competence of the cortical bone. Charlotte Ejersted, Department of Connective Tissue Biology, Institute of Anatomy, University of Aarhus, DK-8000 Aarhus C. Denmark

scholarly journals Growth Hormone and Mild Exercise in Combination Markedly Enhance Cortical Bone Formation and Strength in Old Rats*

Endocrinology ◽  
1998 ◽  
Vol 139 (4) ◽  
pp. 1899-1904 ◽  
Author(s):  
H. Oxlund ◽  
N. B. Andersen ◽  
G. Ørtoft ◽  
H. Ørskov ◽  
T. T. Andreassen
Keyword(s):  
Growth Factor ◽  
Bone Formation ◽  
Cortical Bone ◽  
Formation Rate ◽  
Breaking Load ◽  
Female Rats ◽  
Sectional Area ◽  
Cross Sectional ◽  
Bone Formation Rate ◽  
Factor I

Abstract The effects of a combination of mild exercise and GH injections on bone were studied in old female rats. Biosynthetic human GH, 2.7 mg/kg/day, was injected sc for 73 days. Exercised rats ran 8 m/min on a treadmill for 1 h/day. All rats (age 21 months old) were labeled with a tetracycline injection 56 days and a calcein injection 11 days before killing. The GH injections resulted in an 11-fold increase in femoral middiaphyseal bone formation rate and a 12% increase in cross-sectional area compared with the saline-injected group. The mild exercise doubled the mineralizing surface but did not influence the bone formation rate significantly. The combination of GH injections plus exercise, however, resulted in a further increase of 39% in bone formation rate, primarily at the anterolateral aspects, and an increase of 5% in cross-sectional area compared with the group injected with GH only. The femur ultimate breaking load was increased by 37% and the stiffness by 42% in the group injected with GH compared with the saline-injected group. Exercise alone did not influence the femur mechanical properties. The combination of GH injections plus exercise induced a 4% further increase in ultimate breaking load and 7% further increase in stiffness compared with the group injected with GH alone. The GH injections induced a 117% increase in serum insulin-like growth factor I. The GH-insulin-like growth factor I axis stimulates recruitment of osteoblast precursor cells, resulting in increased bone formation at the periosteal surface. GH injections and mild excercise in combination modulate and increase further the formation and strength of cortical bone in old female rats.

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