A new study published in AJP-Regulatory, Integrative and Comparative Physiology suggests that electroacupuncture to the abdominal region may prevent increases in blood sugar concentrations after a meal by affecting insulin sensitivity and circulating free fatty acid concentrations. Granted this is not comparative physiology research, I find it interesting that electrical stimulation can have such a large impact on metabolism, in mice at least.
Drs. Nicola Abate and Jiande Chen, lead investigators on this study, fed female mice either a diet that was very high in saturated fatty acids (60% fat) or a control diet. After 12 weeks, they performed glucose tolerance tests to see how well the mice disposed of glucose from the blood over the course of two hours. Not surprisingly, a high fat diet impaired glucose tolerance in the animals. What this means is that concentrations of glucose in the blood of the animals fed a high fat diet were significantly higher at 60 mins (491.7 +- 21.9 mg/dl vs. 356 +- 16.6 mg/dl) and 120 mins after the glucose challenge (456.7 +- 28.1 mg/dl vs. 220 +- 17.2 mg/dl) compared to the control fed animals. In other words, the animals developed an impaired ability to respond to or secrete the hormone insulin which is responsible for lowering blood sugar after a meal by stimulating glucose uptake into tissues.
Now here comes the interesting part: 3Hz of electroacupuncture to the abdominal region throughout the glucose challenge reduced blood glucose concentrations by 61.7% at 60 mins and 74.5% at 120 mins post glucose challenge compared to the control fed animals. Further experiments suggest the mechanism: 3Hz electroacupuncture significantly improved their ability to respond to insulin (i.e. insulin sensitivity) and reduced circulating free fatty acid concentrations that are known to cause impaired glucose tolerance.
The acupoints stimulated in the current study were CV4 (Guanyuan) and CV12 (Zhongwan):
J Yin, J Kuang, M Chandalia, D Tuvdendorj, B Tumurbaatar, N Abate, JDZ Chen. Hypoglycemic effects and mechanisms of electroacupuncture on insulin resistance. American Journal of Physiology - Regulatory, Integrative and Comparative Physiology. 307: R332–R339, 2014.
The title should have stated that electric stimulus reduced the blood sugar rise. Calling it electroacupuncture helps give legitimacy to new age practitioners that will call it acupuncture and reduce the importance of the current. When did they localize the meridians on mice?
Could the same have been done with surface electrodes rather than needles?
Also, using an image of a person is a bit misleading.
I agree that it is likely the electrical current that prevented the rise in blood sugar. There was a study published in 2010 that tested the effects of electrical stimulation of the quadriceps alone (without acupuncture) on blood sugar regulation in type 2 diabetics. It did significantly reduce blood sugar, although not to the same extent as seen in the current study (Sharma et al. DOI: 10.4103/0973-3930.70859). Another study of mice found that electrical stimulation alone of the upper abdomen increased blood sugar by inhibiting the vagal nerve, which innervates the pancreas (Ikeda et al., PMID: 1685621).
I have added a cartoon of the acupoints that were stimulated in the mice for the study described in this blog.
Guess it wasn't placebo effect...
Injecting insulin through hollow acupuncture needles has the same effect ;-).
Quite true. :)
It's legitimate to use the term "electroacupuncture" since that was the term used by the authors of the study.
Whether the mechanism has anything in common with the traditional claims of acupuncture, can be tested in a subsequent study. Each of the elements of the treatment can be parsed out and examined on its own.
The advantage of working with mice, as Wesley Dodson noted above, is that there is no placebo effect to worry about.
I'm skeptical of acupuncture as such, but the bottom line is that empirical findings are what they are, and our job is to make sense of them and figure out the mechanisms.
Title and image is misleading;