What’s the News: Retrieving a memory in your brain is a bit like taking an old keepsake off the shelf. If you get startled while holding grandma’s old vase in your hands, you could drop and break it. Memory retrieval is just as vulnerable to disruption, and scientists have tried to exploit this fact to erase PTSD-associated memories with drugs.
A new study in Science tries a different tack, using a behavioral approach to rid people of addictions to drugs. Addiction is sometimes treated with “extinction,” which means showing patients drug-related images while they’re off drugs, so that, for example, they stop associating needles with a high. The researchers found that retrieving drug memories right before an extinction session—basically, giving them a short exposure to drug-related stimulus, followed by a similar but longer exposure session—made the treatment more effective in both rats and humans.
What’s the News: Researchers at the Scripps Research Institute have now created a vaccine that prevents a heroin high in rats. The vaccine, detailed in a recent study in the Journal of Medicinal Chemistry, stimulates antibodies that can stop not only heroin but also its derivative psychoactive compounds from reaching the brain.
What’s the News: Anxiety. Insomnia. Hallucinations. Methamphetamine’s effects on the human brain are well documented, but researchers know relatively little about how the drug affects the body on the molecular scale. Looking at fruit flies (Drosophila melanogaster), scientists have detailed how meth disrupts chemical reactions associated with generating energy, creating sperm cells, and regulating muscles. Most interestingly, they discovered that meth-exposed fruit flies may live longer when they eat sugar. “We know that methamphetamine influences cellular processes associated with aging, it affects spermatogenesis, and it affects the heart,” says University of Illinois entomologist Barry Pittendrigh. “One could almost call meth a perfect storm toxin because it does so much damage to so many different tissues in the body.”
Bath products never sounded so dangerous before. Two methamphetamine-like drugs that are being sold as mere “bath salts” have been linked to hallucinations and suicides, and lawmakers around the country are cracking down. Three states have already banned the substances, and this weekend Senator Charles Schumer announced that he’ll introduce a bill to outlaw the substances at the federal level.
“These so-called bath salts contain ingredients that are nothing more than legally sanctioned narcotics, and they are being sold cheaply to all comers, with no questions asked, at store counters around the country,” said Schumer, a New York Democrat. [Reuters]
The drugs, mephedrone and methylenedioxypyrovalerone (MDPV), can be snorted, injected, or smoked. They have no connection to real bath salts–the scented powders and crystals added to bath water for relaxation. The drugs are commercially labeled with such innocuous names as TranQuility, Blue Silk, and White Lightning, but authorities agree that the effects are anything but innocuous:
Psychotic reactions to snorting the “bath salts” reportedly led one woman to swing a machete at her 71-year-old mother in an attempt to behead her, Panama City Beach police said. Also, a man high on the brand Blue Silk tore up the backseat of a patrol car with his teeth after seven Bay County Sheriff’s Office deputies wrestled the crazed man into the cruiser, the agency said. [Los Angeles Times]
Those delicious chills you get as your favorite piece of music reaches its climax? They’re the result of a glorious spike of dopamine in your brain–that’s the same neurotransmitter that’s involved in reward, motivation, and addiction.
In a nifty series of experiments published in Nature Neuroscience, researchers determined that music provokes floods of dopamine in music lovers. Study coauthor Valorie Salimpoor notes that dopamine has long been known to play a role in more physical activities like taking drugs and having sex, but this research highlights its role in other aspects of our lives.
“It is amazing that we can release dopamine in anticipation of something abstract, complex and not concrete,” Salimpoor said. “This is the first study to show that dopamine can be released in response to an aesthetic stimulus.” [Discovery News]
By combining a cocaine analog with part of a common cold virus, researchers have created a “cocaine vaccine” that tricks the body into attacking the drug, neutralizing its high-giving powers. It has only been tested in mice so far, but the results are good:
“Our very dramatic data shows that we can protect mice against the effects of cocaine, and we think this approach could be very promising in fighting addiction in humans,” study researcher Ronald Crystal, a professor of genetic medicine at Weill Cornell Medical College, said in a statement. [LiveScience]
The immune system doesn’t typically react to cocaine in the blood stream–it’s too small and doesn’t contain the “markers” of an invader. To get the white blood cells to notice it, the researchers strapped it to something the immune system can detect–the outside parts of the virus. The researchers took the outer shell from an adenovirus, which causes some types of the common cold, and removed the parts of the virus that cause illness. Then they linked that recognizable viral shell to a stable molecule similar to cocaine (they also tried it with cocaine itself, the researchers say, but the more-stable analog produced better results).
When it comes to recreational drugs, many assume that most of the dangerous compounds that people get high on are illegal. But drug makers, dealers, and users know better. They are mining the scientific literature for psychoactive drugs, making them in kitchen labs, and selling them to users on the street. And though this poses a real risk for users, it’s perfectly legal.
Purdue University chemist David Nichols says he’s haunted by the knowledge that his scientific research has led to unsafe–and sometimes even deadly–drug use.
“It’s not like you took a gun and shot somebody because then you would know you’d been responsible,” he told the BBC, “but people were taking something that you had published and I was alerting them that this might be an active molecule.” [BBC News]
In an editorial in Nature, Nichols discusses how compounds he has developed are being used as street drugs, with no regards to their safety. Nichols researches compounds for Parkinson’s and schizophrenia and has worked on developing serotonin-regulating analogs of MDMA (commonly known as ecstasy) for use in depression. One of these analogs (called MTA) became a big hit on the streets in the late 1990s.
Without my knowledge, MTA was synthesized by others and made into tablets called, appropriately enough, ‘flatliners’. Some people who took them died. Now, any knowledgeable person who had carefully read our papers might have realized the danger of ingesting MTA…. It really disturbs me that [these people] have so little regard for human safety and human life that the scant information we publish is used by them to push ahead and market a product designed for human consumption. [Nature]
Two new long-lasting options for treating opioid abuse could help heroin addicts avoid relapses.
The new drugs solve a problem with the current treatments for opioid addiction. These drugs, called methadone and buprenorphine, are really just replacement addictions, and their use needs to be closely monitored; patients take them daily at a clinic, because they can be abused by crushing up the pills and injecting them.
The first drug, which was just approved by the FDA, is called Vivitrol: The drug works by blocking the effect of opiates on brain cells, preventing the person from getting high. The effects of one injection last for a full month. In a clinical trial in Russia, 86 percent of people taking Vivitrol hadn’t relapsed after six months, while only 57 percent of placebo patients had stayed clean. However, researchers note that methadone isn’t available in Russia, and say it might be harder to convince addicts in the United States to opt for this treatment.
Vivitrol’s long-acting effect provides a kind of chemical willpower. “Someone who’s interested in not abusing opiates only has to make one good decision a month –- or their family member only has to help them make one good decision a month,”[Phil] Skolnick [of the National Institute on Drug Abuse] says. “That’s why it’s important.” [NPR].
Hallucinogenic drugs are making a comeback–not among the restless youth of today, but among medical researchers. Doctors are increasingly testing illegal drugs like LSD, psychedelic mushrooms, and the party drug ketamine for beneficial effects, and are suggesting that these discredited drugs could have a place in modern medicine. The latest study, published in the Archives of General Psychiatry, found that the active ingredient in hallucinogenic mushrooms helped alleviate depression and anxiety in terminal cancer patients.
“This is a landmark study in many ways,” said Dr. Stephen Ross, clinical director of the Center of Excellence on Addiction at New York University‘s Langone Medical Center, who was not involved in the research. “This is the first time a paper like this has come out in a prestigious psychiatric journal in 40 years.” [Los Angeles Times]
The small pilot study included only a dozen volunteers, so the findings are far from conclusive. The volunteers ranged in age from 36 to 58; all had been diagnosed with advanced-stage cancer and had considerable anxiety as a result of their disease. Each patient had one session in which they were given psilocybin, the active ingredient of magic mushrooms, and another session when they were given a placebo that caused a physiological reaction–still, in most cases the patients could figure out if they’d been dosed or not. In all the sessions the patients were kept under supervision for six hours and were encouraged to lie in the dark while listening to music (no word from the researchers on whether Pink Floyd was provided).
Ketamine for bipolar disorder. LSD for depression. It’s been a busy month for psychedelic drugs in the laboratory, as several studies showed that these drugs typically used recreationally—and illegally—affect the brain in ways that could make them useful for treating mental illness.
First came a small study in the Archives of General Psychiatry that we covered earlier this month, in which scientists tested 18 patients who on average had tried seven kinds of drugs to treat their bipolar disorder. When the researchers gave them small doses of ketamine—a powerful anesthetic that people use recreationally for the hallucinogenic side effects—the patients’ depressive symptoms lessened within a matter of minutes.