Over the weekend a new study was released. The study demonstrates a really cool effect involving the body’s natural pain relief mechanisms. Here is a summary taken from the Science based Medicine blog with a bunch of technical terms to confuse you:
The model used by Nedergaard is a model of inflammation that involves injecting complete Freund’s adjuvant (CFA) into the mice’s paws. As a result, the mice’s paws would become inflamed by the irritant properties of the CFA and thus more sensitive to innocuous stimuli, with a decreased latency period for withdrawal to painful or innocuous stimuli; in other words, the mice’s paws would be more sensitive, and the mice would react more strongly and rapidly to the stimuli of heat or touching. This sensitivity peaked at day four or five and then decreased. As a preliminary experiment, the investigators noted that, after the insertion of acupuncture needles into the mouse limb at the “Zusanli point,” which is located near the knee a microdialysis probe inserted less than a millimeter away registered a spike in extracellular adenosine levels, as well as ATP (which is broken down to adenosine outside of the cells), ADP, and AMP, that peaked at around 30 minutes.
Having established that adenosine was increased within 30 minutes of an acupuncture stimulus, Nedergaard then injected a chemical that binds to the cell receptor activated by adenosine, the A1 receptor agonist, 2-chloro-N(6)-cyclopentyladenosine (CCPA). Injecting CCPA into the Zusanli point greatly improved touch sensitivity and in essence reversed the increased sensitivity to heat. So far, so good. Apparently in the mouse adenosine has a lot to do with modulating pain response in peripheral nerves, and apparently a fair number of pharmaceutical companies are interested in developing adenosine agonists to take advantage of this effect in humans. Even better, this effect was not observed in mice genetically engineered not to make the adenosine A1 receptor, known as A1 receptor knockout mice, strong evidence that it was the A1 receptor that was responsible for the observed blunting of the pain response. Investigators also tested CCPA in a model of neuropathic pain (pain due to nerve dysfunction) and found it worked as well as it did in their model of inflammatory pain.
Basically, when you poke the mice with needles it releases chemicals that relieve pain. Read the link to find more details about what that means. Cool, eh? Except for one thing. Here are some headlines from news sources reporting on the study:
Telegraph: Acupuncture does work as it stimulates a natural pain killer, scientists find (apparently this headline was written by Yoda)
Oh no. And do you think it was just the media presenting the study this way? It wasn’t. Its actually much worse. The study presented itself this way.
The new findings add to the scientific heft underlying acupuncture, said neuroscientist Maiken Nedergaard, M.D., D.M.Sc., who led the research. Her team is presenting the work this week at a scientific meeting, Purines 2010, in Barcelona, Spain.“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, co-director of the University’s Center for Translational Neuromedicine, where the research was conducted.
“In this work, we provide information about one physical mechanism through which acupuncture reduces pain in the body,” she added.
a) What Scientific heft? Everything I have seen shows that acupuncture is nothing more than the placebo effect. Needles aren’t even required. Poking someone with tooth picks and twisting will have the same effect.
b) Since you can stick needles anywhere in your body and get the same effect, then acupuncture, meaning there are specific points where you have to put the needles to unblock your “qi” or whatever, is meaningless.
c) Seriously? You have this cool study that can lead towards all sorts of cool breakthroughs in pain relief and you focus on how it relates to acupuncture! This is the best you can do? Lame.
d) Bloodletting is really old too, should we do studies on mice to see how effective it is in curing disease? What about more in-depth research into the four humours? Just because it is 4000 years old does not mean it works. Science and medicine have progressed a lot since then.
This study in no way shows that acupuncture works. The placebo effect is not a cure, although both Placebo and the Cure are band names, that is about as much as they have in common. This study shows that sticking needles in a mouse’s knee will release ATP leading to pain relief. It shows that it will be worth studying ATP and its uses for pain relief. If you really want to, do more acupuncture studies in humans, but do them right. I’m not denying that acupuncture has an effect, I’m saying that the effect it has it not even close to the purported benefits of acupuncture.
What really upsets me is the complete lack of skepticism in the media. Instead of reading and analyzing they just hop on the bandwagon and go along on the acupuncture ride. The CNet blogger who covered this claims she is a “skeptic.” I’m skeptical about her critical thinking skills. Other than the use of needles, what does this study have to do with acupuncture?
Not a whole lot.