Broken bones can grow again after an injury with the help of a medicine cocktail that activates repair cells for ‘red warning’
Broken bones can be re-grown using a combination of readily available drugs, scientists say.
Two existing medicines have been tested to stimulate the body’s own repair system in the hope of a better treatment of injuries.
Stem cells, which build up new bone, are switched on for ‘red alarm’ and speed up the healing process.
In early research at Imperial College in London, rats resume bone mass in their broken spines within three weeks.
Now that the cocktail has proven to be safe, the team insists on human tasting.
The team could not only create new bone, but also health fractures in the hip, leg and spine. This can make a huge difference for the elderly.
Broken spines can be recovered using a combination of readily available drugs, scientists say. Stem cells, which build new bone, are switched on for ‘red alarm’
In early research at Imperial College in London, rats resume bone mass in their broken spines within three weeks (bottom). The treatment increased calcium to the site of bone injury, thereby accelerating bone formation (at the top, the pink indicated the calcium)
Professor Sara Rankin, corresponding author of the National Heart and Lung Institute study at Imperial College London, said: “The body is constantly repairing itself.
“We know that when bones break they will heal, and this requires the activation of stem cells in the bone. However, when the damage is serious, there are limits to what the body can do on its own.
“We hope that by using these existing drugs to mobilize stem cells, as we did in our new study in rats, we might be able to evoke additional numbers of these stem cells, to increase and accelerate our own ability to repair itself the repair process.
“Further down the line our work could lead to new treatments to repair all types of bone fractures.”
Dr. Andia Redpath, co-lead author of NHLI, said that re-use of existing drugs that help the body heal itself is known as “regenerative pharmacology.”
It can have great potential as an efficient and cost-effective approach to a range of diseases, such as osteoporosis, which causes weakened bones at risk of breaking.
Dr. Redpath said: “Instead of coming up with new stem cell treatments that involve lengthy and expensive studies, our approach uses the power of our own stem cells, using existing medicines.
PAIN IN THE BACK CAN BE CAUSED BY BONE THAT APPEARS AS ‘SWISS CHEESE’
Scientists believe that low back pain can be caused by cartilage in the spine that turns into bone resembling Swiss cheese.
Cartilage should be soft and firm and protect the vertebrae – the 33 pieces of bone that make up the spine.
But tests on mice showed that their tissue changed to a hardened structure with holes as the rodents grew older.
The porous openings allow pain-sensitive nerves to grow and spread deep into the spine, which in turn causes pain.
Johns Hopkins University experimented with mice that were genetically engineered to be at least 20 months old – the equivalent of 70-80 in humans.
They looked for layers of cartilage between each vertebrae, called end plates, that protect the bones and protect them from the weight of the body.
The soft tissue in the spines of the mice was hardened and resembled diffuse bone. It had a Swiss cheese-like structure.
The researchers suspected that the hole structure would provide fertile soil for abnormal nerve growth.
They hope that the discovery can pave the way for better treatment, with patients currently dependent on standard painkillers.
The findings were published in Nature Communications in January.
“We already know that the treatments in our research are safe, now it’s just a matter of further investigating whether they help our body heal.”
The marrow – the spongy tissue in the bone – mobilizes different types of stem cells to help repair and regenerate tissue after injury or illness.
But there is a limit to how many cells are produced and what they can do. It is currently not possible for a spine to grow bone.
The latest study suggests that this can change with the help of two drugs; CXCR4 antagonist, used in bone marrow transplants and beta-3 adrenergic agonist, used for bladder control.
Researchers, including scientists from Beaumont Health in the US, gave the combination of lab rodents with broken spines.
Their bone volume increased after three weeks. Recovery of bone movement, or recovery of additional tissue such as nerves, has not been investigated.
The drugs were found to activate the marrow to release mesenchymal stem cells, a type that can turn into bone.
The rats received a single treatment, which also helped the binding of calcium to the site of bone injury, thereby accelerating bone formation.
One of the drugs used was to cause fat cells to fire into the marrow to release naturally occurring chemicals known as endocannabinoids that promote bone formation.
The researchers point out that other plant cannabinoids, such as cannabis, would not have the same effect because they act on the brain instead of the bone marrow.
Reporting their findings in the journal Regenerative Medicine, British and American teams said the drug combinations should now be tested in humans.
It can be used to repair fractures that have resisted healing, as well as common and painful breaks for which there is currently no other treatment than relieving symptoms.
Elderly people and people in late middle age can be the biggest beneficiaries, because bot loses its ability to heal with age.
But professional athletes, soldiers and others who need to recover from bone damage as soon as possible before their career can also find it useful.
First author Dr. Tariq Fellous, also from NHLI, said: “We must first see if these drugs release stem cells in healthy volunteers before we can test them in patients with fractures.
“We have the drugs and know they are safe to use with people – we only need the funding for the human trials.”