Pubdate: Mon, 06 Jan 2014
Source: Arizona Republic (Phoenix, AZ)
Copyright: 2014 The Arizona Republic
Contact: http://www.azcentral.com/arizonarepublic/opinions/sendaletter.html
Website: http://www.azcentral.com/arizonarepublic/
Details: http://www.mapinc.org/media/24
Author: Steven Reinberg, HealthDay

RODENT STUDY FINDS A HORMONE THAT MAY TAKE HIGH OUT OF WEED

In experiments with rodents, scientists have discovered that a 
steroid hormone blunts the effects of marijuana, virtually 
eliminating its high.

The hormone, pregnenolone, occurs naturally in the body. In the 
laboratory, it worked by reducing the reaction to THC 
(tetrahydrocannabinol), the intoxicating ingredient in marijuana, the 
researchers said.

"When the brain is stimulated by high doses of THC, it produces 
pregnenolone - a 3,000 percent increase - that inhibits the effects 
of THC," said senior researcher Dr. Pier Vincenzo Piazza of 
Neurocentre Magendie in Bordeaux, France.

Pregnenolone does this by blocking the activity of the type-1 
cannabinoid receptor (CB1) in the brain, Piazza said.

Although research conducted in animals doesn't necessarily apply to 
humans, Piazza said he hopes a drug based on the hormone could combat 
marijuana addiction or allow researchers to isolate the medicinal 
properties of marijuana while blocking consequences such as memory impairment.

The findings, published in last week's issue of the journal might be 
timely because some observers fear that growing legalization of 
marijuana in the United States will increase marijuana addiction. 
Colorado and Washington state have voted to legalize marijuana for 
recreational use, and 20 states and Washington, D.C., are legalizing 
its medical use. In addition, many states are decriminalizing its use.

Piazza said his study points to the potential hazards of marijuana. 
"If we have a built-in mechanism that protects us from an 
over-activation of the CB1 receptor by THC, smoking cannabis cannot 
be that innocuous," he said.

The dose of THC needed to produce pregnenolone is greater than that 
usually found in cannabis users, he said. But in higher doses, he 
said, "we can use this natural protective mechanism to develop new 
therapies for cannabis abuse."

But pregnenolone by itself won't work because it quickly degrades 
after it's taken, Piazza said. However, his team has developed a 
class of compounds that retains pregnenolone's anti-cannabis effects 
and are stable and absorbed well in the body. "We hope to be able to 
test them in humans very soon," he said.

Some experts are skeptical of Piazza's conclusions.

Mitch Earleywine, a professor of psychology at the University at 
Albany, State University of New York, isn't convinced that a drug 
based on this hormone will work on humans or is even needed.

"Although the authors pitch this as a novel way to treat cannabis 
abuse, it's actually a superb - if partial - explanation for why 
cannabis appears to have no potential lethal dose and why its 
capacity for creating addiction is more like caffeine's than that of 
any illicit drug," he said.

Earleywine also said he's cautious about using data from rodent 
experiments to predict what will happen in humans.

"I'm always reluctant to generalize from rat studies, and some of 
these reactions only work with rats and not mice," he said. "We 
should be supremely careful before we start drawing conclusions for 
primates, let alone humans."

Moreover, a medication to treat marijuana problems is potentially 
unnecessary, Earleywine said.

Existing therapies, such as motivational interviewing and behavior 
therapy for relapse prevention, can be effective, he said.

"Behavioral interventions have no adverse side effects," he said. "We 
can't say the same for futzing around with pregnenolone or the 
complex, interconnected series of human hormones."

Scott Krakower, assistant unit chief of psychiatry at Zucker Hillside 
Hospital in Glen Oaks, N.Y., said a drug to treat marijuana abuse is needed.

"We don't have a lot of drug treatments for marijuana," he said. 
"However, I don't think we can say right now that pregnenolone is 
going to be helpful."

Krakower said he isn't sure how such a drug would be used - whether 
it could curb an acute problem or provide a long-term therapy.

Like all other addictions, marijuana abuse needs both medication and 
counseling, he said.

"Right now, the treatments for marijuana addiction are therapy," 
Krakower said. "Research like this leads to hope that one day we are 
going to have drugs to help those suffering from marijuana addiction."

According to the American Cancer Society, use of pregnenolone pills 
and capsules is promoted by some people to increase energy and as an 
alternative treatment for fatigue. Others say pregnenolone 
supplements help treat various medical conditions. But scientific 
evidence is scant, and little is known about its long-term effects, 
according to the society.
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MAP posted-by: Jay Bergstrom