The formation of bone and fat is very much interdependent as both tissues originate from the same type of progenitor cells: mesenchymal stem cells. These either evolve into osteoblast, cells that build up bone mass, or into adipocytes, fat cells, respectively. Factors supporting the formation of fat tissue inhibit bone regeneration at the same time and thereby negatively impact bone quality.
A team of scientists from the Universities of Dresden, Leipzig and Ulm has now identified a novel protein controlling this interaction in a study recently published in Science Translational Medicine. CD90/Thy-1, as the protein is named, enhances bone regeneration, while concurrently inhibiting the accumulation of fat tissue. Mice lacking this protein have brittle bone and grow fatter. Furthermore, the scientists showed that both patients with osteoporosis and patients who are overweight exhibit lower serum levels of CD90/Thy-1 than healthy patients. Further investigations will likely reveal, whether this factor can be applied to improve bone quality in patients with overweight in future, or act as a marker for early diagnosis of bone loss.
Further information: Press release
Original publication in Science Translation Medicine: “Thy-1 (CD90) promotes bone formation and protects against obesity“, Doi:10.1126/scitranslmed.aao680.