Posts tagged addiction
Articles and news from the latest research reports.
Are you addicted to the Internet? You might be able to blame your genes.
Scientists say they’ve found a link between a toxic relationship with the Web and a genetic quirk that also plays a role in nicotine addiction.
Researchers at the University of Bonn in Germany interviewed 843 people about their online habits. Of them, 132 showed signs of an unhealthy relationship with the Internet — all of their thoughts revolved around it and their sense of wellbeing was shaken if they couldn’t go online. By comparing the genes of the two groups, the researchers found the subset of likely Internet addicts more often carried a mutation the CHRNA4 gene, which is typically linked to nicotine addiction.
Scientists find switch in the brain that could cause psychosis and addiction for cannabis users
(Source: Daily Mail)
A new UCLA study pinpoints uniquely human patterns of gene activity in the brain that could shed light on how we evolved differently than our closest relative. Published Aug. 22 in the advance online edition of Neuron, these genes’ identification could improve understanding of human brain diseases like autism and schizophrenia, as well as learning disorders and addictions.
(Image by Michael Nichols)
How PTSD and Addiction Can Be Safely Treated Together
The vast majority of people with addiction have suffered significant previous trauma, and many people who struggle with addiction suffer from post-traumatic stress disorder (PTSD) simultaneously. But the treatment of these patients has posed a conundrum: experts have believed that PTSD treatment should not begin until the addicted person achieves lasting abstinence, because of the risk that PTSD treatment may trigger relapse, yet addicted people with untreated PTSD are rarely able to abstain for long.
Now, a new study suggests that there may be no need to wait. Researchers found that using exposure therapy — the gold-standard treatment for PTSD, which involves exposure to memories and reminders of patients’ past trauma — can successfully reduce symptoms of PTSD, even when people with addiction continue to use drugs. And, although exposure therapy requires patients to face some of their worst fears, it does not increase their drug use or prompt them to drop out of treatment more than ordinary addiction therapy, the study found.
“The exciting thing in my view is that [the study] supports people with drug and alcohol problems having access to other forms of psychological interventions, rather than being fobbed off and told to sort out their alcohol or drug problem first,” says Michael Farrell, director of the National Drug and Alcohol Research Center at the University of New South Wales in Sydney, Australia, where the research was conducted.
The finding could potentially help the majority of those who suffer from addiction or PTSD: one-half to two-thirds of people with addictions suffer from PTSD concurrently, or have in the past, and about the same proportion of people with PTSD also have substance use disorders.
The new study involved 103 people with both conditions. Most were addicted to multiple drugs, primarily heroin, marijuana and alcohol. More than two-thirds of the participants had been traumatized during childhood, with almost half reporting a history of sexual abuse.
Researchers randomly assigned half of the participants to simply continue the addiction treatment of their choice, whether it was detoxification leading to abstinence, residential treatment or maintenance on medications like methadone and buprenorphine (Suboxone, Subutex).
The other half received their usual treatment, plus exposure therapy for PTSD, which consisted of 13 one-on-one sessions with a clinical psychologist, meeting about once a week for 90 minutes at a time. The therapy began with education about PTSD and addiction, including instruction on cognitive techniques to address distressing thoughts that could lead to relapse. Then, when patients were ready, they were exposed to reminders of their traumatic experience, which they usually avoided out of fear of triggering flashbacks and intense anxiety. Exposure therapy works to reduce or eliminate these PTSD symptoms by breaking patients’ cycle of fear and avoidance.
Indeed, participants in the exposure treatment “demonstrated significantly greater reductions in PTSD symptom severity compared with participants randomized to receive usual treatment alone,” the authors wrote. However, drug use in the exposure therapy group didn’t decline any more than it did in the usual treatment group. Both groups saw a reduction in the severity of addiction but in each case, the majority of participants continued to use drugs. Notably, however, drug use did not increase due to exposure therapy.
“These findings challenge the widely held view that patients need to be abstinent before any trauma work, let alone prolonged exposure therapy, is commenced,” the authors wrote. “[F]indings from the present study demonstrate that abstinence is not required.”
Importantly, however, while the findings showed that carefully delivered exposure therapy can help, they did not support the practice of forcing addicts to confront trauma in settings where they do not feel safe or in control. Exposure therapy is calibrated so that patients do not become overwhelmed or feel helpless; in contrast, coercion by the therapist can re-traumatize patients and worsen both PTSD and addiction symptoms, previous studies have shown.
In other words, it’s not clear that treating people with addiction by compelling them to recall or re-enact traumatic experiences — a commonly used tactic in group settings — actually helps. What the current study shows is that when trained clinical psychologists carefully deliver exposure therapy in a tightly monitored trial, they can help ease PTSD symptoms in people with addiction.
August 15, 2012
Source: TIME
In a major breakthrough, an international team of scientists has proven that addiction to morphine and heroin can be blocked, while at the same time increasing pain relief.
The team from the University of Adelaide and University of Colorado has discovered the key mechanism in the body’s immune system that amplifies addiction to opioid drugs. Laboratory studies have shown that the drug (+)-naloxone will selectively block the immune-addiction response. The results - which could eventually lead to new co-formulated drugs that assist patients with severe pain, as well as helping heroin users to kick the habit - will be published in the Journal of Neuroscience.
"Our studies have shown conclusively that we can block addiction via the immune system of the brain, without targeting the brain’s wiring," says the lead author of the study, Dr Mark Hutchinson, ARC Research Fellow in the University of Adelaide’s School of Medical Sciences.
"Both the central nervous system and the immune system play important roles in creating addiction, but our studies have shown we only need to block the immune response in the brain to prevent cravings for opioid drugs."
Watch a video of Dr Mark Hutchinson talking about this study.
A fine-tuned combination of two existing pharmaceutical drugs has shown promise as a potential new therapy for people addicted to cocaine—a therapy that would reduce their craving for the drug and blunt their symptoms of withdrawal.
In laboratory experiments at The Scripps Research Institute, the potential therapy, which combines low doses of the drug naltrexone with the drug buprenorphine, made laboratory rats less likely to take cocaine compulsively—a standard preclinical test that generally comes before human trials.
While the two-drug combination would have to prove safe and effective for people in clinical trials before approval by the U.S. Food and Drug Administration (FDA), the work represents a significant advance in the field because there are currently no FDA-approved medications for treating cocaine addiction.
A better judge of character with oxytocin nasal spray?
In other contexts, oxytocin is already well-known as the “bliss hormone”. The hormone is secreted upon stimulation by touch and is known to result in a feeling of calm and physical relaxation. It is also used to induce labour in childbirth and as an aid for women experiencing difficulties in breastfeeding.
Oxytocin has also been referred to as a “mindreading” hormone. Recent research findings show that there may be some truth to these claims – although the mindreading component may have a more down-to-earth explanation.
Ecstasy Harms Memory With One Year of Recreational Use
New research published online July 25 by the scientific journal Addiction, gives some of the first information available on the actual risk of using ecstasy. It shows that even in recreational amounts over a relatively short time period, ecstasy users risk specific memory impairments. Further, as the nature of the impairments may not be immediately obvious to the user, it is possible people wouldn’t get the signs that they are being damaged by drug use until it is too late.
According to the study, new ecstasy users who took ten or more ecstasy pills over their first year of use showed decreased function of their immediate and short-term memory compared with their pre-ecstasy performance. These findings are associated with damage of the hippocampus, the area of the brain that oversees memory function and navigation. Interestingly, hippocampal damage is one of the first signs of Alzheimer’s disease, resulting in memory loss and disorientation.
New Vaccine for Nicotine Addiction Successfully Tested in Mice
June 27th, 2012
Weill Cornell researchers develop novel antibody vaccine that blocks addictive nicotine chemicals from reaching the brain.
Researchers at Weill Cornell Medical College have developed and successfully tested in mice an innovative vaccine to treat nicotine addiction.
In the journal Science Translational Medicine, the scientists describe how a single dose of their novel vaccine protects mice, over their lifetime, against nicotine addiction. The vaccine is designed to use the animal’s liver as a factory to continuously produce antibodies that gobble up nicotine the moment it enters the bloodstream, preventing the chemical from reaching the brain and even the heart.
“As far as we can see, the best way to treat chronic nicotine addiction from smoking is to have these Pacman-like antibodies on patrol, clearing the blood as needed before nicotine can have any biological effect,” says the study’s lead investigator, Dr. Ronald G. Crystal , chairman and professor of Genetic Medicine at Weill Cornell Medical College.
“Our vaccine allows the body to make its own monoclonal antibodies against nicotine, and in that way, develop a workable immunity,” Dr. Crystal says.
The new vaccine has been tested in mice and could one day help people to quit smoking cigarettes, should they choose. Much testing remains until the vaccine can be tested in humans. Image is in the public domain.
Previously tested nicotine vaccines have failed in clinical trials because they all directly deliver nicotine antibodies, which only last a few weeks and require repeated, expensive injections, Dr. Crystal says. Plus, this kind of impractical, passive vaccine has had inconsistent results, perhaps because the dose needed may be different for each person, especially if they start smoking again, he adds.
“While we have only tested mice to date, we are very hopeful that this kind of vaccine strategy can finally help the millions of smokers who have tried to stop, exhausting all the methods on the market today, but find their nicotine addiction to be strong enough to overcome these current approaches,” he says. Studies show that between 70 and 80 percent of smokers who try to quit light up again within six months, Dr. Crystal adds.
About 20 percent of adult Americans smoke, and while it is the 4,000 chemicals within the burning cigarette that causes the health problems associated with smoking — diseases that lead to one out of every five deaths in the U.S. — it is the nicotine within the tobacco that keeps the smoker hooked.
A new kind of vaccine
There are, in general, two kinds of vaccines. One is an active vaccine, like those used to protect humans against polio, the mumps, and so on. This kind of vaccine presents a bit of the foreign substance (a piece of virus, for example) to the immune system, which “sees” it and activates a lifetime immune response against the intruder. Since nicotine is a small molecule, it is not recognized by the immune system and cannot be built into an active vaccine.
The second type of vaccine is a passive vaccine, which delivers readymade antibodies to elicit an immune response. For example, the delivery of monoclonal (identically produced) antibodies that bind on to growth factor proteins on breast cancer cells shut down their activity.
The Weill Cornell research team developed a new, third kind — a genetic vaccine — that they initially tested in mice to treat certain eye diseases and tumor types. The team’s new nicotine vaccine is based on this model.
The researchers took the genetic sequence of an engineered nicotine antibody, created by co-author Dr. Jim D. Janda, of The Scripps Research Institute, and put it into an adeno-associated virus (AAV), a virus engineered to not be harmful. They also included information that directed the vaccine to go to hepatocytes, which are liver cells. The antibody’s genetic sequence then inserts itself into the nucleus of hepatocytes, and these cells start to churn out a steady stream of the antibodies, along with all the other molecules they make.
In mice studies, the vaccine produced high levels of the antibody continuously, which the researchers measured in the blood. They also discovered that little of the nicotine they administered to these mice reached the brain. Researchers tested activity of the experimental mice, treated with both a vaccine and nicotine, and saw that it was not altered; infrared beams in the animals’ cages showed they were just as active as before the vaccine was delivered. In contrast, mice that received nicotine and not treated with the vaccine basically “chilled out” — they relaxed and their blood pressure and heart activity were lowered — signs that the nicotine had reached the brain and cardiovascular system.
The researchers are preparing to test the novel nicotine vaccine in rats and then in primates — steps needed before it can be tested ultimately in humans.
Dr. Crystal says that, if successful, such a vaccine would best be used in smokers who are committed to quitting. “They will know if they start smoking again, they will receive no pleasure from it due to the nicotine vaccine, and that can help them kick the habit,” he says.
He adds that it might be possible, given the complete safety of the vaccine, to use it to preempt nicotine addiction in individuals who have never smoked, in the same way that vaccines are used now to prevent a number of disease-producing infections. “Just as parents decide to give their children an HPV vaccine, they might decide to use a nicotine vaccine. But that is only theoretically an option at this point,” Dr. Crystal says. “We would of course have to weight benefit versus risk, and it would take years of studies to establish such a threshold.”
“Smoking affects a huge number of people worldwide, and there are many people who would like to quit, but need effective help,” he says. “This novel vaccine may offer a much-needed solution.”
Source: Neuroscience News
Drug addiction study offers new insight on compulsive behavior
June 25, 2012
The same neurological mechanism involved in the transition from habitual to compulsive drug use could underlie less severe, but still harmful, compulsive behaviours.
"We’re trying to understand individuality in addictive behaviour. Many people can be exposed to drugs with addictive potential, for instance, but not everyone will become addicted,” explains Eric Dumont, an associate professor in the Department of Biomedical and Molecular Sciences. “We believe we’ve identified a mechanism that makes certain people predisposed to developing addictions, and it’s possible that the same mechanism underlies many - perhaps most - compulsive behaviours.”
The mechanism occurs in a reward pathway of the brain. In this pathway, the brain maintains a delicate balance between pleasure and aversion, ensuring that moment-to-moment desires and dislikes remain in sync with the biological needs of the body.
Dr. Dumont and his team found unusual activity in this pathway when modeling drug addiction in rats, which exhibit a genetic predisposition to addiction comparable to humans. They believe that the pathway’s balance is prone to becoming unbalanced in a certain percentage of the population. The signal to stop an activity reverses to a green light.
The team hopes that by identifying this mechanism, and possibly others like it, they will allow researchers to better understand and monitor a range of compulsive behaviours. Accordingly, Dr. Dumont’s team collaborates with Dr. Cella Olmstead, associate professor of Psychology at Queen’s, who recently developed an animal model of compulsive sucrose intake.
Dr. Dumont and this team were recently awarded a $520,000 operating grant from Canadian Institutes of Health Research (CIHR) to support their work for the next five years in understanding the neurological processes behind addiction behaviour.
Provided by Queen’s University
Source: medicalxpress.com