Stem Cells: The Building Blocks of Life

 

 

     Osteoporosis decreases bone density, leaving the bones abnormally porous and thereby increasing the risk of fracture. Patients with osteoporosis have fragile bones that do not heal quickly on their own. Researchers are attempting to employ stem cells to expedite the healing process.

     Scientists at the University of North Carolina School of Medicine engineered mesenchymal stem cells (MSCs), multipotent stem cells that can give rise to osteoblasts (bone cells), to express growth factor-1. (Growth factors are polypeptides that stimulate cell proliferation) The modified MSCs were transplanted into mice with bone fractures. They successfully closed the fracture and strengthened the bone.

     Researchers led by Professor Kit Lam at the UC Davis Health System engineered a new molecule, the LLP2A-alendronate. This molecule causes the MSCs residing in the bone marrow to travel to the bones' surface and differentiate into osteoblasts. From there on, the osteoblasts synthesize bone. The molecule was injected into mice that had osteoporosis. After twelve weeks, bone mass and strength increased in the femur and vertebrae. This therapy is unique in that it does not involve stem cell transplantation. Instead, it stimulates body's stem cells and allows them to do the healing. 

     Currently, these therapies have only been tested on animals. However, scientists are optimistic they can apply these treatments to humans. "These results are very promising for translating into human therapy," said Jan Nolta, professor of internal medicine, an author of the study and director of the UC Davis Institute for Regenerative Cures. "We have shown this potential therapy is effective in rodents, and our goal now is to move it into clinical trials."