TEL AVIV, Israel — From a simple tooth to a major knee replacement, dental and orthopedic implant surgeries to common around the globe. However, these procedures can fail due to the immune system’s response to bacteria or metal particles coming off the implants. Now, a new study reveals a drug typically used with Alzheimer’s patients may prevent painful inflammation and rejection of the replacement.
Researchers at Tel Aviv University say this inflammatory response can lead to the activation of osteoclasts, bone resorbing cells. These cells trigger a condition called osteolysis, which destroys the bone tissue around the implant. Once this process begins, scientists say it’s almost impossible to stop and will result in the patient losing their implant.
In the new report, study authors developed an active molecule (SNV) which comes from the short protein vasoactive intestinal peptide (VIP). The study finds this molecule can both suppress inflammation and ward off the destruction of bone tissue. Researchers believe the breakthrough will help patients having knee implantations, those with dental implants, and even people suffering gum recession due to gum disease.
An implant medication you can rub into the skin?
VIP works as a neurohormone and neurotransmitter and has ties to several different processes, including expanding blood vessels, expanding respiratory passages, cell division, and nerve protection. Until now, scientists have been using it as a treatment for brain cell health in patients dealing with dementia.
However, researchers attached a lipid (fat) to this protein, making the molecule “fatty” enough to penetrate the skin. Study authors say this will allow patients to use the drug as an ointment instead of an injection or oral medication.
“I recently met friends and relatives who had undergone knee or tooth implantations, and I understand the great need of patients for such medications. I hope we can help them,” says Professor Illana Gozes in a media release.
“For years I have worked on VIP – the important protein hormone that maintains the viability of brain cells and also plays a part in sexual activity. We were first in the world to isolate the VIP gene, at a time when genetic cloning was in its infancy. We were also first to develop drug candidates by binding VIP with a lipid to create SNV – a molecule that can penetrate the skin and serve as an ointment drug. At that time, we tried to apply the molecule to problems of impotence and Alzheimer’s disease, in collaboration with Prof. Mati Fridkin of the Weizmann Institute. Recently I came upon a totally different direction, in which we discovered that SNV is effective for protecting bones against inflammatory processes triggering bone resorption.”
Stopping the harmful effects of implant leakage
Researchers tested the molecule’s impact on both bone cells and immune cells. During their experiments, the team discovered metal particles coming from the implants accelerate the progression of bone resorption. However, in animal tests, study authors found SNV could suppress this resorption. Therefore, the new drug shows great promise at preserving the hold joint implants and teeth have in the surrounding bone tissue.
“This project is a classic example of collaboration between different departments at TAU’s Faculty of Medicine,” says Prof. Yankel Gabet.
“On the one hand, together with Prof. David Kohavi, my group has for years studied the connection between the immune system, inflammatory response, and bone cells. On the other, Dr. Michal Eger is a dentist who decided to explore these processes for her doctoral thesis. She attended a course given by Prof. Gozes, in which VIP and SNV were discussed, and an in-depth conversation led to the idea of checking whether these molecules can prevent bone loss around implants and natural teeth. We quickly discovered the enormous potential of SNV for people who suffer from bone loss around teeth and implants. Currently we are working on translating this new discovery to the clinic.”
The study appears in the journal Frontiers in Pharmacology.