Effects of simulated weightlessness on bone metabolism in rats at different ages.

Di Yi Jun Yi Da Xue Xue Bao

Department of Orthopedics and Traumatology, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China.

Published: July 2002

Objective: To compare the effects of simulated weightlessness on age-related bone metabolism and on the mechanical parameters of the weight-bearing bones of rats at different ages.

Methods: Two-month-old and 6-month-old rats (8 in each group) were both subjected to tail suspension test for up to 4 weeks, with 2 groups of rats of corresponding ages (n=8) serving as control. The bone metabolism markers, biomechanical parameters of the femurs, along with the growth and mineral contents of the tibia, were respectively measured and compared with those of the controls.

Results: The bone formation markers, alkaline phosphatase and osteocalcin levels, dropped drastically in both groups of rats undergoing tail suspension test (P<0.01), which also induced significant hypocalcaemia (P<0.01). Bone material loss of the tibia occurred in both groups of rats receiving the test (P<0.01) whose effect on the volume and mass of fresh tibia was age-related (P<0.05), but the degree of mineral loss was not consistent with calcium loss in rats at different ages. Except for elastic deformation (P>0.05), both structural and biomechanical properties altered significantly after tail suspension test (P<0.01), and the changes of maximum deformation and maximum load were related to the age of the rats (P<0.05).

Conclusion: The result is an age-related difference in the response of bone metabolism to simulated weightlessness.

Download full-text PDF

Source

Publication Analysis

Top Keywords

bone metabolism
12
effects simulated
8
simulated weightlessness
8
tail suspension
8
suspension test
8
groups rats
8
rats
5
bone
4
weightlessness bone
4
metabolism rats
4

Similar Publications

Alcoholic osteonecrosis of the femoral head (AIONFH) is caused by long-term heavy drinking, which leads to abnormal alcohol and lipid metabolism, resulting in femoral head tissue damage, and then pathological necrosis of femoral head tissue. If not treated in time in clinical practice, it will seriously affect the quality of life of patients and even require hip replacement to treat alcoholic femoral head necrosis. This study will confirm whether M2 macrophage exosome (M2-Exo) miR-122 mediates alcohol-induced BMSCs osteogenic differentiation, ultimately leading to the inhibition of femoral head necrosis.

View Article and Find Full Text PDF

Background: Lysinuric protein intolerance is a rare autosomal disorder caused by mutations in the Slc7a7 gene that lead to impaired transport of neutral and basic amino acids. The gold standard treatment for lysinuric protein intolerance involves a low-protein diet and citrulline supplementation. While this approach partially improves cationic amino acid plasma levels and alleviates some symptoms, long-term treatment is suggested to be detrimental and may lead to life-threatening complications characterized by a wide range of hematological and immunological abnormalities.

View Article and Find Full Text PDF

The histone demethylase KDM5C enhances the sensitivity of acute myeloid leukemia cells to lenalidomide by stabilizing cereblon.

Cell Mol Biol Lett

January 2025

Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Jiangsu Province Engineering Research Center of Precision Diagnostics and Therapeutics Development, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Suzhou Key Laboratory of Drug Research for Prevention and Treatment of Hyperlipidemic Diseases, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, China.

Background: The protein cereblon (CRBN) mediates the antileukemia effect of lenalidomide (Len). Len binds to CRBN, recruits IKZF1/IKZF3, and promotes their ubiquitination and degradation, through which Len exhibits its antileukemia and antimyeloma activity. Therefore, the protein level of CRBN might affect the antiproliferative effect of Len.

View Article and Find Full Text PDF

Sport participation affects body composition and bone health, but the association between sport, body composition, and bone health in female athletes is complex. We compared areal bone mineral density (aBMD, DXA) and tibial volumetric bone mineral density (vBMD), geometry, microarchitecture, and estimated strength (HR-pQCT) in cross-country runners (n = 22), gymnasts (n = 23) and lacrosse players (n = 35), and investigated associations of total body lean mass (TBLM), team, and their interaction with tibial bone outcomes. Total body (TB), total hip (TH), femoral neck (FN), and lumbar spine (LS) aBMD were higher in gymnasts than runners (p < 0.

View Article and Find Full Text PDF

This study examines the biocompatibility, osteogenic potential, and effectiveness of polyether ether ketone (PEEK) composites for treating osteonecrosis, seeking to establish a theoretical basis for clinical application. A range of PEEK composite materials, including sulfonated polyether ether ketone (SPEEK), polydopamine-sulfonated polyether ether ketone (SPEEK-PDA), bone-forming peptide-poly-dopamine-sulfonated polyether ether ketone (SPEEK-PDA-BFP), and vascular endothelial growth factor-poly-dopamine-sulfonated polyether ether ketone (SPEEK-PDA-VEGF), were constructed by concentrated sulfuric acid sulfonation, polydopamine modification and grafting of bioactive factors. The experiments involved adult male New Zealand rabbits aged 24-28 weeks and weighing 2.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!