Relationships between physical activity and metacarpal cortical bone mass and bone resorption in hemiplegic patients

2001 ◽  
Vol 6 (3) ◽  
pp. 227-233 ◽  
Author(s):  
Jun Iwamoto ◽  
Tsuyoshi Takeda ◽  
Shoichi Ichimura
Keyword(s):  
Physical Activity ◽  
Bone Resorption ◽  
Bone Mass ◽  
Cortical Bone ◽  
Cortical Bone Mass

scholarly journals Influence of a School-based Physical Activity Intervention on Cortical Bone Mass Distribution: A 7-year Intervention Study

2016 ◽  
Vol 99 (5) ◽  
pp. 443-453 ◽  
Author(s):  
Jesper Fritz ◽  
Rachel L. Duckham ◽  
Timo Rantalainen ◽  
Björn E. Rosengren ◽  
Magnus K. Karlsson ◽  
...  
Keyword(s):  
Physical Activity ◽  
Bone Mass ◽  
Cortical Bone ◽  
Mass Distribution ◽  
Intervention Study ◽  
Physical Activity Intervention ◽  
School Based ◽  
Cortical Bone Mass

Effect of chronic metabolic acidosis on bone density and bone architecture in vivo in rats

2014 ◽  
Vol 306 (5) ◽  
pp. F517-F524 ◽  
Author(s):  
Jürg A. Gasser ◽  
Henry N. Hulter ◽  
Peter Imboden ◽  
Reto Krapf
Keyword(s):  
Metabolic Acidosis ◽  
Bone Resorption ◽  
Bone Mass ◽  
Cortical Bone ◽  
Bone Microarchitecture ◽  
Chronic Metabolic Acidosis ◽  
Ovx Rats ◽  
Cortical Bone Mass ◽  
Trabecular Number

Chronic metabolic acidosis (CMA) might result in a decrease in vivo in bone mass based on its reported in vitro inhibition of bone mineralization, bone formation, or stimulation of bone resorption, but such data, in the absence of other disorders, have not been reported. CMA also results in negative nitrogen balance, which might decrease skeletal muscle mass. This study analyzed the net in vivo effects of CMA's cellular and physicochemical processes on bone turnover, trabecular and cortical bone density, and bone microarchitecture using both peripheral quantitative computed tomography and μCT. CMA induced by NH4Cl administration (15 mEq/kg body wt/day) in intact and ovariectomized (OVX) rats resulted in stable CMA (mean Δ[HCO3−]p = 10 mmol/l). CMA decreased plasma osteocalcin and increased TRAP5b in intact and OVX animals. CMA decreased total volumetric bone mineral density (vBMD) after 6 and 10 wk ( week 10: intact normal +2.1 ± 0.9% vs. intact acidosis −3.6 ± 1.2%, P < 0.001), an effect attributable to a decrease in cortical thickness and, thus, cortical bone mass (no significant effect on cancellous vBMD, week 10) attributed to an increase in endosteal bone resorption (nominally increased endosteal circumference). Trabecular bone volume (BV/TV) decreased significantly in both CMA groups at 6 and 10 wk, associated with a decrease in trabecular number. CMA significantly decreased muscle cross-sectional area in the proximal hindlimb at 6 and 10 wk. In conclusion, chronic metabolic acidosis induces a large decrease in cortical bone mass (a prime determinant of bone fragility) in intact and OVX rats and impairs bone microarchitecture characterized by a decrease in trabecular number.

scholarly journals Inhibition of Bone Resorption by Pamidronate Cannot Restore Normal Gain in Cortical Bone Mass and Strength in Tail-Suspended Rapidly Growing Rats

1997 ◽  
Vol 12 (7) ◽  
pp. 1058-1067 ◽  
Author(s):  
Yoshiaki Kodama ◽  
Konosuke Nakayama ◽  
Hiroaki Fuse ◽  
Seiji Fukumoto ◽  
Hajime Kawahara ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Bone Mass ◽  
Cortical Bone ◽  
Growing Rats ◽  
Cortical Bone Mass

scholarly journals The myokine irisin increases cortical bone mass

2015 ◽  
Vol 112 (39) ◽  
pp. 12157-12162 ◽  
Author(s):  
Graziana Colaianni ◽  
Concetta Cuscito ◽  
Teresa Mongelli ◽  
Paolo Pignataro ◽  
Cinzia Buccoliero ◽  
...  
Keyword(s):  
Physical Activity ◽  
Adipose Tissue ◽  
Bone Mass ◽  
Cortical Bone ◽  
Low Dose ◽  
Bending Strength ◽  
Molecular Entity ◽  
Weekly Dose ◽  
Mineral Density ◽  
Cortical Bone Mass

It is unclear how physical activity stimulates new bone synthesis. We explored whether irisin, a newly discovered myokine released upon physical activity, displays anabolic actions on the skeleton. Young male mice were injected with vehicle or recombinant irisin (r-irisin) at a low cumulative weekly dose of 100 µg kg−1. We observed significant increases in cortical bone mass and strength, notably in cortical tissue mineral density, periosteal circumference, polar moment of inertia, and bending strength. This anabolic action was mediated primarily through the stimulation of bone formation, but with parallel notable reductions in osteoclast numbers. The trabecular compartment of the same bones was spared, as were vertebrae from the same mice. Higher irisin doses (3,500 µg kg−1 per week) cause browning of adipose tissue; this was not seen with low-dose r-irisin. Expectedly, low-dose r-irisin modulated the skeletal genes, Opn and Sost, but not Ucp1 or Pparγ expression in white adipose tissue. In bone marrow stromal cell cultures, r-irisin rapidly phosphorylated Erk, and up-regulated Atf4, Runx2, Osx, Lrp5, β-catenin, Alp, and Col1a1; this is consistent with a direct receptor-mediated action to stimulate osteogenesis. We also noted that, although the irisin precursor Fndc5 was expressed abundantly in skeletal muscle, other sites, such as bone and brain, also expressed Fndc5, albeit at low levels. Furthermore, muscle fibers from r-irisin–injected mice displayed enhanced Fndc5 positivity, and irisin induced Fdnc5 mRNA expression in cultured myoblasts. Our data therefore highlight a previously unknown action of the myokine irisin, which may be the molecular entity responsible for muscle–bone connectivity.

Sign in / Sign up

Export Citation Format

Share Document