Researchers may have found a hormonal way to block pot smokers from getting high. They say the findings could someday lead to new treatments for addiction.
A study published in Science on Jan. 3 shows that pregnenolone, a hormone that is a building block for other steroid hormones like androgens and estrogen, can mitigate the effects of the active ingredient in marijuana, tetrahydrocannabinol (THC).
Through rodent studies, researchers discovered a new neural breaking system involving cannabis, pregnenolone and the cannabinoid receptors (CB1). When the subject had THC in their system, the CB1 receptors were activated, and the subject felt the effects. However, if there was a lot of pregnenolone present, it slowed down the CB1 receptors. In other words, the subjects couldn’t get as high.
“We’ve now added another whole layer onto our understanding of that (CB1) system,” study author Ruth Ross, head of pharmacology at the University of Toronto, told the Toronto Star.
Advocates claim that marijuana has medicinal effects including pain-relieving abilities and appetite-inducing qualities that can help people who suffer from a variety of conditions including cancer, multiple sclerosis and epilepsy. Currently, medical marijuana is legal in 20 states and the District of Columbia. In addition, Colorado legalized the sale of regulated marijuana for recreational purposes on Jan. 1, 2014. The state of Washington is expected to begin allowing regulated sales without a prescription in late spring.
Pregnenolone can’t block all of THC’s effects because it only interacts with the CB1 receptors. This means that it’s likely that just the biggest problems associated with smoking too much weed -- memory loss, motivation issues and the need to smoke more -- would be affected.
The researchers believe that this hormone may be able to help people who are addicted and provide "the first pharmacological therapy for cannabis dependence," lead author Pier Vincenzo Piazza of the French Institute of Health and Medical Research (INSERM) told AFP. He hopes to start clinical trials involving pregnenolone in the next year to year and a half.
Dr. Margaret Haney, director of the Marijuana Research Laboratory and a professor in the department of psychiatry at Columbia University Medical Center, previously told CBS News that about 10 percent of marijuana users will find themselves dependent on the drug. This could lead to withdrawal symptoms when they try to quit, including trouble sleeping, irritability, anxiety and decreases in food consumption.
Piazza acknowledged in a press release, however, that pregnenolone treatments are still far off because the hormone is not absorbed well in oral treatments and it turns into other steroid hormones when it enters the bloodstream. They hope that synthetic forms of the hormone might be more effective for humans.
"We have now developed derivatives of pregnenolone that are well absorbed and stable,” he said. “They then present the characteristics of compounds that can be used as new class of therapeutic drugs. We should be able to begin clinical trials soon and verify whether we have indeed discovered the first pharmacological treatment for cannabis dependence."
But, Mitch Earleywine, a professor of psychology at the University at Albany, State University of New York, told HealthDay he isn’t sure that we need a treatment to block people from getting high. He emphasized that this hormone was only shown to work in rodents, and it doesn’t necessarily mean it would be effective for humans.
"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.
In an earlier interview with CBS News, Haney also pointed out that more research needs to be done to understand the medicinal benefits of marijuana. Her lab is currently working on studies to look at the chemical components in marijuana called cannabinoids to see how exactly they treat certain symptoms. They are also looking at other ways to give active cannibinoids to patients in non-smokeable forms.
“Just like you’re skeptical of a pharmaceutical industry and what they say a drug does, you have to be just as skeptical about what marijuana does, because people are making enormous profit from it,” Haney said. “That is again why we need carefully controlled studies to demonstrate what it works for and what it doesn’t work for.”
According to 2010 U.S. government statistics, about 17.4 million people used marijuana in the month before being surveyed. It is the most commonly abused illicit drug, used by 76. 8 percent of people who admitted to consuming banned substances.
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