Scientists in Aberdeen who have been researching osteoporosis and other bone diseases have made a finding that could pave the way for new drugs to treat these disorders.
Their studies also suggest that cannabis use might affect users’ bone health, although researchers stress that further research would be required to confirm this.
As part of an Arthritis Research Campaign funded study into brittle bones and other diseases, the research team explored the effects of chemicals produced naturally in our body called endogenous cannabinoids on bone.
These substances – termed “cannabinoids” - act in the same way that cannabis does by attaching themselves to receptors in our body which then play a part in a number of the body’s processes including controlling our appetite.
In findings published online today by the journal Nature Medicine (Sunday, May 22), the researchers reveal their discovery that these receptors are also present in bone cells and play a crucial role in regulating bone density and bone turnover.
They also discovered that if they used drugs to block the cannabinoid receptors, this was highly effective in preventing bone loss.
Professor Stuart Ralston, who led the research project, and is now based at the University of Edinburgh, said: “This is an important finding since it demonstrates that the receptors which cannabis acts upon are not only important in the nervous system, but also in the control of bone metabolism.
“The fact that compounds which blocked cannabinoid receptors are highly effective at preventing bone loss is particularly exciting, since it shows that these drugs could provide us with a completely new approach to the treatment of osteoporosis and other bone diseases. “
Dr Ruth Ross, who is a cannabinoid research scientist at the University of Aberdeen, added: “Cannabinoid receptor blockers have recently been shown to be safe and effective for the treatment of obesity. The fact that they may also be potent inhibitors of bone loss has major therapeutic implications."
Conversely, the researchers also discovered that drugs which stimulate these receptors - and mimic the effects of cannabis – were detrimental to bone and caused increased bone loss, which could, in turn lead to osteoporosis.
More than 250,000 people in Britain suffer osteoporosis-related fractures each year with related health care costs of over £1,700 million.
However, the most widely used of drug treatments for osteoporosis, cancer-related bone diseases, rheumatoid arthritis and other bone diseases are inconvenient to take and can be associated with various undesirable side effects.
Professor Ralston added: “There is a real need to identify new drugs that can inhibit bone loss, and it looks like blockers of cannabinoid receptors may fit the bill as a new class of drugs for the treatment of bone disease.”
The Arthritis Research Campaign gave £157,000 to Professor Ralston and his team when he was Professor Medicine and Bone Metabolism at the University of Aberdeen. Professor Ralston is now Arthritis Research Campaign Professor of Rheumatology at the University of Edinburgh.
The team’s paper Regulation of bone mass, bone loss and osteoclast activity by cannabinoid receptors appears on the Nature Medicine website.