Our Friend MSCs (Mesenchymal Stem Cells)—Bringing New Life to Old Bones

Researchers from the University of Toronto and The Ottawa Hospital were looking to see if mesenchymal stem cells (MSCs) might treat osteoporosis. MSCs are multipotent stromal cells that can differentiate into a variety of cell types, including: bone cells (osteoblasts), cartilage cells (chondrocytes), muscle cells (myocytes) and fat cells (adipocytes).
Faulty MSCs are the culprits behind osteoporosis; after injecting healthy MSCs into mice with the affliction that causes bones to become weak and brittle, researchers were hoping for a general increase in the mice’s bone health. Instead, they were surprised (and probably very excited) to discover after six months—a quarter of a mouse’s life span—that healthy, functioning bone had replaced the damaged osteoporotic bone. The bone structure in the little creatures, which had been severely compromised by osteoporosis, had been restored to a normal, healthy state! The healthy mesenchymal stem cells did what they were born to do. They became bone cells and went to work, much like the restoration of an old building at the hands of architects and laborers, only without the scaffolds and noise. MSCs work very quietly.
Researchers are hoping that these findings could lead to a new way of treating osteoporosis in humans, or even delay its onset indefinitely.
Stem cell researchers have known for some time that MSCs can boost the regeneration of bone, and in fact a test group of elderly patients in the U.S. who suffer from osteoporosis have already received MSC injections as part of an ancillary trial. The research team is preparing to to examine their blood samples to see if biological markers indicate an improvement in bone growth and bone reabsorption.
Depending on the outcome of those blood tests, larger trials involving human patients could follow within the next 5 years.
In addition to working quietly and therefore not waking you to the sound of a jackhammer at 7 a.m., there are other cool qualities to MSCs. For instance, they are “a heterogeneous population of musculoskeletal progenitors (another name for adult stem cells) that includes skeletal stem cells (SSCs).” An added perk is that they can be transplanted between individuals without the need to be matched, and without the risk of rejection.
MSCs are awesome.
Globally, more than 200 million people are living with either postmenopausal osteoporosis—known as type 1 osteoporosis, which affects mainly women, or age-related type 2 osteoporosis, which affects both men and women.
With type 2 osteoporosis, there is a reduction in the inner structure of the bone. The bone becomes thinner and less dense, and it can no longer function properly.
Worldwide, type 2 osteoporosis leads to around 8.9 million bone fractures annually. Hip fractures are among the most common fractures related to osteoporosis, which can lead to disability and even death in elderly patients.
Currently, Teriparatide (brand name Fortéo) is the only drug available to treat type 2 osteoporosis, and its effectiveness lasts for only two years.
The senior author of the study, titled Systemic Mesenchymal Stromal Cell Transplantation Prevents Functional Bone Loss in a Mouse Model of Age-Related Osteoporosis, and published March 17, 2016, is William Stanford, Ph.D., a senior scientist at The Ottawa Hospital Research Institute and a professor at the University of Ottawa. Previous research led Stanford to discover the association between defects in MSC and age-related osteoporosis in mice.
The study’s co-author, John E. Davies, Ph.D., D.Sc., is a professor at the University of Toronto’s Institute of Biomaterials and Biomedical Engineering, The study’s findings are published in the current issue of Stem Cells Translational Medicine.