Bone Abstracts

This study aims at determining if casein would lead to a better bone status than soy in the context of a moderate protein restriction (6% of total energy intake) in growing mice.Ten-week-old female Balb/C mice were divided in four groups of 15 animals. Two groups received 6% of their energy intake as protein, one as casein and the other as soy protein. The third group was a normal-protein control receiving 20% soy protein. The last group (positive contro...

Small GTPases of the Rho family (RhoA and Rac-1) are responsible for cytoskeleton dynamics (particularly actin polymerisation) and control cellular tension. For these reasons, they are implicated in the commitment of multipotent cells (MCs). In one hand, increased tension (important RhoA activity) is commonly associated with osteogenesis (OS), in the other hand, a reduced one (low RhoA activity) is associated with adipogenesis (AD). Nevertheless, precise RhoGTPases regulations...

Bone sialoprotein regulates osteoblast activity and bone formation. In knockout (BSP−/−) mouse bone marrow (BM) stromal cell cultures, the pool of osteoprogenitor (OP) cells (CFU-F number) is not different from wild-type (+/+), nor is their early differentiation (same numbers of alkaline phosphatase positive colonies=CFU-ALP, although these are smaller), while the number of osteoblast, mineralized colonies (CFU-OB) is dramatically reduced. Because ossifi...

The bone organ integrates the activity of bone tissue, bone marrow, and blood vessels and the factors ensuring this coordination remain ill defined. Bone sialoprotein (BSP) is with osteopontin (OPN) a member of the small integrin binding ligand N-linked glycoprotein (SIBLING) family, involved in bone formation, hematopoiesis, and angiogenesis. In rodents, bone marrow ablation induces a rapid formation of medullary bone which peaks by ~8 days (d8) and is blunted in BSP...

Intrinsic quality, micro and nano structure of bone after 1 month of spaceflight and during 1 week of recovery had never been investigated. The aim was to explore these properties in appendicular and axial skeleton of mature mice.Ten C57/Bl6 male mice flew on the 30-day space Russian BION-M1 high-orbit satellite mission (Biomedical Ethics Commission of IBMP, n°319). Five were euthanized 12 h after landing, the others 8 days later. A ground control g...