The next time someone mentions acupuncture as an option to relieve that backache of yours, don’t scoff. Researchers have uncovered how it may really work.
Acupuncture originated from Eastern medicine more than 4,000 years ago and more than 8 million Americans have tried it, according to the National Institutes of Health. Acupuncture involves inserting fine needles in pressure points all over the body and manipulating them to relieve pain. The effectiveness of this treatment has remained controversial, however, with studies showing mixed results and scientists finding few concrete clues to explain how it works.
Now, however, researchers have uncovered part of this mystery.
“We have provided the first evidence that acupuncture releases a natural pain-relieving molecule into the body,” says lead investigator Maikin Nedergaard, co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center in New York.
The body naturally produces a painkiller called adenosine into injured tissue when you cut your finger or break your arm. Adenosine is produced by cells in response to an injury and helps blunt some of the hurt by blocking pain-transmitting nerve signals.
Nedergaard’s team discovered the role of adenosine in acupuncture by performing the treatment on mice that had discomfort in their right paw. The mice each received a 30-minute acupuncture treatment at a well-known acupuncture point near the knee, with very fine needles rotated gently every five minutes to mimic a typical session.
During and immediately after the treatment, the level of adenosine in the tissues near the needles was 24 times greater than before the treatment and reduced paw discomfort by two-thirds. The mice also experienced less pain simply by increasing their adenosine levels with no acupuncture treatment.
Acupuncture, however, did not help relieve pain or increase adenosine production when the needles were simply inserted into the acupuncture point without rotation. The treatment also did not work in mice specially designed to lack adenosine receptors.
“You can’t be more clear than that,” Nedergaard says. “Adenosine is key to reducing pain during acupuncture treatment.”
The researchers then explored a combination treatment to boost adenosine levels even more. In addition to acupuncture, the team gave the mice a cancer drug known to prolong the molecule’s lifetime in tissue. This combination almost tripled the accumulation of adenosine in the muscles and more than tripled the time the needle treatment was effective. This study was published online May 30 in Nature Neuroscience.
“Although the authors propose a compelling new mode of action for acupuncture, we cannot be sure about the mechanism until we have convincing data from human pain patients,” says Edzard Ernst, a professor of complementary medicine at University of Exeter in England.
Nedergaard agrees that these results need to be confirmed in humans, adding, “We can hopefully use this new knowledge to optimize pain-relief treatments.”
