Kudzu extract curbs alcohol intake

The isoflavone puerarin, extracted from kudzu, the invasive Chinese vine that runs rampant in several parts of the United States, was found to slow the rate of alcohol consumption in a small pilot study and may be useful to deter binge drinking.

The study, led by David M. Penetar, PhD, from McClean Hospital and Harvard Medical School, Boston, Massachusetts, was published online May 9 in Drug and Alcohol Dependence.

"We started looking at kudzu in our laboratory 15 years ago," Dr. Penetar told Medscape Medical News. Study coauthor David Y.-W. Lee, PhD, from the Department of Bio-Organic and Natural Products Laboratory at McLean Hospital, in Belmont, Massachusetts, has a lot of experience with Chinese medicine. "He knew that extracts of the kudzu root have been used to treat alcohol-related problems for years," he said.

With animal studies showing that these extracts reduced alcohol consumption, the next step was to see whether this would work in humans, Dr. Penetar said.

The study included 10 healthy adult volunteers (average age, 25.8 years, ±3.2 years) who drank an average of 17.6 drinks (±9.7) per week. None of the study participants had an alcohol abuse problem, Dr. Penetar noted.

"They were all students or working, young adults, and we screened very carefully so that we did not include people in the study who did have drinking problems," he said.

Acting as their own controls, the participants took puerarin, 1200 mg daily, in a double-blind, placebo-controlled crossover design for 1 week before an afternoon drinking session.

The drinking sessions were conducted in a "natural setting" that was furnished like a small apartment living room with an overstuffed recliner, bookshelves, pictures, carpeting, lamps, a TV, a DVD player, and stereo equipment. It also had a small kitchen area with a sink and a small refrigerator where beer, juice, and water were kept.

The volunteers came individually to the apartment-laboratory on 4 separate occasions for a drinking session. They had to abstain from drinking alcohol from 11:00 pm the night before and were not allowed to consume caffeinated drinks after 9:00 am on the day of the drinking session.

The drinking sessions began at 4:30 pm and lasted 1.5 hours. The volunteers had access to up to 6 bottles of their preferred brand of beer, in addition to juice and water.

"This was a simulation of a binge drinking episode, where you drink a lot of drinks at the beginning," Dr. Penetar said.

The researchers also recorded the time spent drinking, the sip volumes, and the total amount of alcohol that was consumed.

When the volunteers took the kudzu extract, they drank significantly less. On average, they consumed 3.5 (±0.55) beers when treated with placebo, and 2.4 (±0.41) beers when treated with puerarin.

After taking placebo, 3 volunteers drank 5 beers, and 1 drank all 6 beers. In contrast, after taking puerarin, none of the volunteers drank 5 or 6 beers. Also, after taking puerarin, the volunteers decreased sip size, took more sips to finish a beer, and took longer to drink each beer. They also took longer to open the next beer when on puerarin.

"They didn't stop completely, but they did reduce how much they drank. We think this compound may help people who binge drink to cut back on how much they consume," Dr. Penetar said.

The extract did not have any adverse effects and did not make anyone sick, he added.

Promising Study
Joanne Fertig, PhD, of the National Institute on Alcohol Abuse and Alcoholism (NIAAA) in Rockville, Maryland, which funded the study, told Medscape Medical News that the study was promising, but small.

The human laboratory model, in which volunteers drank in a natural, living room–type setting, is an interesting one, she said.

"This is a good example of a human laboratory study, in which people are brought into comfortable settings where researchers can measure how much of the drink is being taken with each sip, and also whether people are drinking more slowly under one condition as opposed to another. It is an interesting model to study drinking behavior," Dr. Fertig said.

The caveats are that the study results are very preliminary and that the population in the study were not alcohol dependent, she said.

"So, the bottom line is it's interesting, it's preliminary, it's small, and we are going to continue funding it," Dr. Fertig said.


Source: http://www.medscape.com/viewarticle/764263?sssdmh=dm1.787408&src=nldne