A brain region for addiction?

From physorg:

An animal study released Thursday bolsters the notion that drug cravings can be "switched off" by shutting down a key part of the brain, a finding that could have implications for treating addicts. Researchers have previously shown that damage to the insula can dramatically extinguish a smoker's need for nicotine.

The obvious next step is to see if this holds true for other addictions, such as as alcohol, overeating, and other drugs. Surprisingly, what researchers found in rat studies is that anesthetizing the insula also decreased unwanted medication side effects.

Chilean researchers have shown that temporarily "silencing" the insula suppresses cravings in drug-addicted rats and insulates them from the unpleasant side effects of medication, according to the study published in Science.

They hypothesize that this may be the brain region responsible for drug cravings, and that future treatments for addiction should target the insula.

Drugs are bad: smoking bad for alcohol, antidepressants bad for bones

Sure, this is common sense, but I never realized the magnitude of the neurocognitive damage.

Science Daily — Alcoholics frequently smoke. Anywhere from 50 to 90 percent of individuals in North America who seek alcoholism treatment are also chronic smokers. New findings indicate that smoking may interfere with alcoholics' neurocognitive recovery during their first six to nine months of abstinence from alcohol.

And, as if treating elderly depressed people wasn't difficult enough, between their hesitation in coming in to seek help, and the multitude of comorbid medical conditions, there is now the risk of worsening their osteoporosis if we give them SSRI antidepressants.

Science Daily — The class of antidepressant medications known as selective serotonin reuptake inhibitors may be associated with an increased rate of bone loss in older men and women, according to two articles in the June 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Chinese "e-cigarette": get your nicotine without the toxins

That's right, an electronic cigarette. Costs $208, and is already available in China, Israel, Turkey, and various European countries.

Golden Dragon Group Ltd's Ruyan cigarettes are battery-powered, cigarette-shaped devices that deliver nicotine to inhalers in a bid to emulate actual smoking.

"It feels like a cigarette, looks like a cigarette, it even emits vapor. In many ways, it is like an actual smoking experience, and that's what makes us different," he told Reuters.

Being marketed as a nicotine replacement replacement, this seems just too much like a cigarette to me. However, the harm reduction approach would support this, because there is no more exposure to the tars and other toxins generated from burning tobacco products. It's a cooler, sexier version of the nicotrol inhaler.

http://www.reuters.com/article/lifestyleMolt/idUSSP23039020070509

Just one dose of morphine can permanently change the brain

Depressing, isn't it? Especially since heroin turns into morphine once it enters the body.

"A single dose of morphine may affect a brain region involved in addiction, making addiction more likely, scientists report in Nature. One dose of morphine blocked those nerve cell connections in the rats' brains. That created a surge in dopamine levels, throwing off the brain's chemical balance.
"It's as if a brake were removed," Kauer says in a Brown University news release.
The activity in the rats' brains after one shot of morphine "could increase vulnerability to addiction," Kauer says. "The brain may, in fact, be learning to crave drugs."

Definitely makes chemical dependency tough to treat, since people are causing irreversible neurochemical brain changes. Hopefully they'll eventually make better drugs to fix this someday.

http://www.webmd.com/mental-health/news/20070425/nudging-the-brain-toward-addiction?src=RSS_PUBLIC

Don't smoke, exercise!

"As little as five minutes of exercise seems to help smokers curb their craving for a cigarette, a review of a dozen studies found.
The research showed that moderate exercise, such as walking, significantly reduced the intensity of smokers' nicotine withdrawal symptoms.
"If we found the same effects in a drug, it would immediately be sold as an aid to help people quit smoking," said Dr. Adrian Taylor, the study's lead author and professor of exercise and health psychology at the University of Exeter.

Their hypothesis: "Nearly anything that distracts people from smoking is thought to help, but scientists have long suspected that exercise might have a more potent effect. Taylor theorized that exercise could produce the mood-enhancing hormone dopamine, which could, in turn, reduce smokers' nicotine dependence."

Sounds like it's time to teach exercise in smoking cessation programs.

http://www.cnn.com/2007/HEALTH/03/13/fitness.smoking.ap/index.html?eref=rss_health

Duh! Nicotine is addictive, even for squirrel monkeys

In the name of science, they are getting squirrel monkeys addicted to nicotine too.

"This study is the first of its kind to evaluate the motivational value of nicotine in experimentally naive monkeys. "

They found: "These results demonstrate that nicotine plays a critical role in maintaining smoking behaviour," said lead researcher Dr. Le Foll. "

Yes, the nicotine itself is what addicts people. Sure, there is the ritual involved with smoke breaks, such as oral gratification and chat breaks through the day, but for these monkeys, it's all about the nicotine.

"In these tests, the animals could voluntarily self-administer nicotine by pressing on a lever. Receiving nicotine was associated with distinctive environmental cues, to mimic the situation associated with tobacco smoke in humans. Whereas animals initially showed no preference for the active lever, over time a strong preference for the lever delivering nicotine developed. Animal subjects were motivated to press a lever up to 600 times to get a single injection of nicotine.
"This clearly demonstrates a high motivation to get nicotine that develops over time", said Dr. Le Foll. "

They say their goal is to find better drugs to treat tobacco dependence. So much for not getting exposed in the first place.

http://www.sciencedaily.com/releases/2007/02/070227105219.htm

Antidepressants Help Men, But Not Women, Decrease Alcohol Consumption

I don't know how much antidepressants 'help' per say, but there is definitely a correlation.

Study background: "14,063 Canadian residents aged 18-76 years were surveyed. The survey included measures of quantity, frequency of drinking, depression and antidepressants use, over the period of a year.
The researchers used data from the GENACIS Canada survey, part of an international collaboration to investigate the influence of cultural variation on gender differences in alcohol use and related problems."

Findings: " Non-depressed men consumed 436 drinks per year, compared to 579 drinks for depressed men not using antidepressants, and 414 drinks for depressed men who used antidepressants.
Unfortunately for women, the alcohol use remained higher whether those experiencing depression took antidepressants or not. The numbers are telling: 179 drinks per year for non-depressed women, 235 drinks for depressed women not using antidepressants, and 264 drinks for depressed women who used antidepressants."

Conclusions: "While men suffering from depression generally consume more alcohol than non-depressed men, those who use antidepressants consume alcohol at about the same level as non-depressed men."

There are still many possible explanations for this that have nothing to do with the actual effects of the antidepressants themselves. Hopefully their next study can try to tease those out.

http://www.sciencedaily.com/releases/2007/02/070227105517.htm

Synthetic compound blocks alcoholism in rats

Researchers have created a synthetic compound, MTIP, blocks the activity of Corticotropin-releasing factor (CRF) in the brain under stress while not interacting under normal situations.

"CRF levels in the brain rise in the short term after drinking; in subjects that are not dependent, this activation returns to normal within a day or so. The new study shows that the CRF system becomes overactive in the long term in animals with a history of alcohol dependence, increasing the risk for relapse. "

Researchers speculate that they might be able to use MTIP to eventually treat many diseases in addition to alcoholism where CRF levels are high. This includes anxiety and depression.

If this someday turns into a prescription medication, it could change the field of chemical dependency practice.

Currently, there are no 'good' drugs for alcoholism. The three main ones for preventing alcohol relapse are naltrexone (Revia), acamprosate (Campral), or disulfiram (Antabuse). The first two are supposed to decrease cravings and/or decrease the euphoria associated with alcohol. The third, and oldest (antabuse), helps to curb alcohol relapse by making you physically ill if you drink (you will vomit, have nausea, etc...).

Surprisingly (to me, at least) I have more patients on antabuse than the other 2 combined. It is likely due to the culture of my clinic, but many patients who choose antabuse and stay on it really do swear by it. In general, I am not a firm believer in aversion therapies, but having patients who choose antabuse as a deterrent to relapse, and watching it actually work for them really forces me to reconsider.

http://www.sciencedaily.com/releases/2007/03/070307075548.htm

Predisposition to Addiction Found in Cocaine Study

The neurotransmitter in question is dopamine.

The receptor deficiency is D2 (one of the types of dopamine receptor) .

The specific brain area is the ventral (front) area of the striatum, the nucleus accumbens.

Details of the study: "Researchers at the University of Cambridge in England report in this week's Science that a lower number of specific types of receptors that bind the neurotransmitter dopamine—a chemical central to the brain's reward system—in the front (or ventral) section of the striatum (a midbrain region implicated in planning and movement as well as executive function) correlates to increased impulsive behavior in rats. In addition, they found that the more impulsive animals, when given the option, consumed more cocaine than the calmer rats did. "
http://www.sciam.com/article.cfm?chanID=sa003&articleID=102E18AA-E7F2-99DF-31F85020F2B25647&ref=rss

This just means that some brains are more susceptible to drug addiction, and they hypothesize that deficiencies in the D2 receptor in the nucleus accumbens of the brain may explain why.

Clinical Implications (aka how I'll use it with my patients):
Many chemically dependent patients have a lot of guilt and poor self esteem around their drug abuse. This is not necessarily a bad thing, but when they start expanding this into judgements about their moral character, and being a 'bad' person, it can get in the way of treatment. By explaining to them that their addictive nature may be at least partially due to brain chemistry, it often helps them to separate out addiction from morality. I don't mean to imply that someone is not responsible for their actions. Rather, it's that if someone knows their brain has a vulnerability (ie. addiction), then they need to change their environment and/or behavior(s) if they want to stay out of trouble.
A less charged example: if you are diabetic, your body just can't process carbohydrates and sugars as well as the average person. It doesn't make you a bad person because your body is different. However, if you don't make accommodations (ie. change your diet, take medications or insulin, make efforts to keep you blood glucose in balance), you will get sick, your organs will fail, and it will likely kill you.

Basically, this supports the disease model for addiction and mental illness, rather than a character judgement about the 'weakness' of an individual. Doesn't mean they can use this as an excuse to abuse drugs either, unless they want to give up on the idea of free will.

Happy Friday everyone!