Scientists at the University of Rochester Medical Center have offered new insights into how acupuncture alleviates pain.
The researchers identified the molecule adenosine as a central player in parlaying some of the effects of acupuncture in the body.
Building on that knowledge, scientists were able to triple the beneficial effects of acupuncture in mice by adding a medication approved to treat leukemia in people.
The research focuses on adenosine, a natural compound known for its role in regulating sleep, for its effects on the heart, and for its anti-inflammatory properties.
But adenosine also acts as a natural painkiller, becoming active in the skin after an injury to inhibit nerve signals and ease pain in a way similar to lidocaine.
In the current study, scientists found that the chemical is also very active in deeper tissues affected by acupuncture.
The Rochester researchers looked at the effects of acupuncture on the peripheral nervous system - the nerves in our body that aren't part of the brain and spinal cord.
The research complements a rich, established body of work showing that in the central nervous system, acupuncture creates signals that cause the brain to churn out natural pain-killing endorphins.
The new findings add to the scientific heft underlying acupuncture, said neuroscientist Maiken Nedergaard, who led the research.
"Acupuncture has been a mainstay of medical treatment in certain parts of the world for 4,000 years, but because it has not been understood completely, many people have remained skeptical," said Nedergaard.
"In this work, we provide information about one physical mechanism through which acupuncture reduces pain in the body," she added.