A mother's touch may protect against drug cravings later
An attentive, nurturing mother may be able to help her children better resist the temptations of drug use later in life, according to a study in rats conducted by Duke University and the University of Adelaide in Australia.
A rat mother's attention in early childhood actually changes the immune response in the brains of her pups by permanently altering genetic activity, according to Staci Bilbo, an assistant professor of psychology and neuroscience at Duke, who led the research. High-touch mothering increased the brain's production of an immune system molecule called Interleukin-10, leaving these rats better able to resist the temptation of a dose of morphine much later in life.
This is the first study to show how morphine causes a molecular response in the glial cells of the brain's reward centers, which had only recently been identified as part of drug addiction's circuitry. "We set out to find out what that response looks like," Bilbo said.
To program some of the rat pups to produce more IL-10, the researchers used an established technique called the "handling paradigm," in which very young rat pups are removed from their mother's cage for 15 minutes and then returned. "As soon as they're returned, she checks them out vigorously," grooming the pups and cleaning them, Bilbo said. For a control group, another set of pups were never removed. Some of them had more attentive mothers than others, just by natural variation.
The animals then were put through a test called the "place preference chamber," a two-roomed cage in which they would be given a dose of morphine if they entered one side, or a dose of saline on the other. Over the next four weeks, the rats were returned to the two-sided chamber three times a week for five minutes, but were never given another dose of morphine. Initially, they all showed a preference for the morphine side, but over time, the handled rats showed little preference, which indicated their craving had been "extinguished," Bilbo said.
About 8 weeks after their first exposure to morphine, the animals were each given a very small dose of morphine to prime craving and then returned to the 2-sided chamber. The non-handled control rats preferred spending time in the morphine chamber; the handled rats still showed no clear preference.
Morphine activates the glial cells of the brain to produce inflammatory molecules which signal a reward center of the brain called the nucleus accumbens. But IL-10 works against that inflammation and reward. The more IL-10 the brain produces, the less likely morphine would cause an increase in craving or relapse weeks after the initial experience with the drug.
The brains of the rat pups who experienced high-touch mothering were found to have more active genes for producing IL-10 in the microglial cells of the brain, which apparently "completely knocked out this drug-seeking behavior," Bilbo said. They were producing about four times as much IL-10 as the control animals. "The nurturing moms can profoundly change outcomes," Bilbo said.
This is a change not of the genes themselves, but of the way they are controlled by something called methylation, which can keep a gene's activity suppressed. High-touch mothering removed methylation on the IL-10 gene, making these rats produce more of the anti-inflammatory molecule.
To further prove that IL-10 levels were key to the craving, the researchers used a drug called ibudilast to artificially increase IL-10 production in a group of control rats. These rats experience craving extinction much the same as the high-touch rats.
It's important to note that the genetic modification created by the mothering didn't change the initial rewarding effect of the morphine, it altered the craving for that reward much later, Bilbo said.
Bilbo said her team next wants to look at the long-term effects of maternal stress on the brain's immune response. They'll be working with the Children's Environmental Health Initiative at Duke, which examines real-world environmental health effects in Durham, NC in collaboration with the US Environmental Protection Agency.
More information: "Early-Life Experience Decreases Drug-Induced Reinstatement of Morphine CPP in Adulthood via Microglial-Specific Epigenetic Programming of Anti-Inflammatory IL-10 Expression," Jaclyn M. Schwarz, Mark R. Hutchinson and Staci D. Bilbo. The Journal of Neuroscience, Dec. 6, 2011. DOI -10.1523/JNEUROSCI.3297-11.2011
Provided by Duke University
- Source found for immune system effects on learning, memory Oct 26, 2011 | not rated yet | 0
- The biggest loser: Maternal obesity puts a load on her offspring that lasts a lifetime Feb 09, 2010 | not rated yet | 0
- New medication more potent, longer lasting than morphine Jan 04, 2011 | not rated yet | 0
- Study first to confirm long-term benefits of morphine treatment in infants Nov 03, 2008 | not rated yet | 0
- A safer, more effective morphine may be possible with IU discovery Mar 24, 2011 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
How can there be a term called "intestinal metaplasia" of stomach
17 hours ago Hello everyone, Ok Stomach's normal epithelium is simple columnar, now in intestinal type of adenocarcinoma of stomach it undergoes "intestinal...
Pressure-volume curve: Elastic Recoil Pressure don't make sense
May 18, 2013 From pressure-volume curve of the lung and chest wall (attached photo), I don't understand why would the elastic recoil pressure of the lung is...
If you became brain-dead, would you want them to pull the plug?
May 17, 2013 I'd want the rest of me to stay alive. Sure it's a lousy way to live but it beats being all-the-way dead. Maybe if I make it 20 years they'll...
MRI bill question
May 15, 2013 Dear PFers, The hospital gave us a $12k bill for one MRI (head with contrast). The people I talked to at the hospital tell me that they do not...
Ratio of Hydrogen of Oxygen in Dessicated Animal Protein
May 13, 2013 As an experiment, for the past few months I've been consuming at least one portion of Jell-O or unflavored Knox gelatin per day. I'm 64, in very...
Alcohol and acetaminophen
May 13, 2013 Edit: sorry for the typo in the title , can't edit I looked around on google quite a bit and it's very hard to find precise information on the...
- More from Physics Forums - Medical Sciences
More news stories
Activating an enzyme known to play a role in the anti-aging benefits of calorie restriction delays the loss of brain cells and preserves cognitive function in mice, according to a study published in the May ...
Neuroscience 7 hours ago | 5 / 5 (3) | 0 |
(Medical Xpress)—Despite spending billions of dollars on research and development, drug companies have been unable to come up with effective treatments for dementia and Alzheimer's Disease (AD). Now, A. ...
Neuroscience 10 hours ago | 4.9 / 5 (9) | 0 |
You're standing near an airport luggage carousel and your bag emerges on the conveyor belt, prompting you to spring into action. How does your brain make the shift from passively waiting to taking action when ...
Neuroscience 11 hours ago | 5 / 5 (1) | 0 |
(Medical Xpress)—Native peoples in regions where cameras are uncommon sometimes react with caution when their picture is taken. The fear that something must have been stolen from them to create the photo ...
Neuroscience 12 hours ago | 4.2 / 5 (5) | 0 |
In a remote fishing community in Venezuela, a lone fisherman sits on a cliff overlooking the southern Caribbean Sea. This man –– the lookout –– is responsible for directing his comrades on the water, ...
Neuroscience 14 hours ago | 4 / 5 (1) | 0 |
Australian scientists have charted the path of insulin action in cells in precise detail like never before. This provides a comprehensive blueprint for understanding what goes wrong in diabetes.
12 hours ago | 4.5 / 5 (6) | 0 |
An experimental sleeping pill from US drug company Merck is effective at helping people fall and stay asleep, according to reviewers at the US Food and Drug Administration, which could soon approve the new drug.
6 hours ago | 3 / 5 (2) | 0
A drug commonly used to treat depression and anxiety may improve a stress-related heart condition in people with stable coronary heart disease, according to researchers at Duke Medicine.
8 hours ago | 5 / 5 (1) | 0 |
Researchers at USC have found that a class of pharmaceuticals can both prevent and treat Alzheimer's Disease in mice.
9 hours ago | 5 / 5 (4) | 0 |
Children with autism showed significant improvement after six months of simple sensory exercises at home using everyday items such as scents, spoons and sponges, according to UC Irvine neurobiologists.
10 hours ago | not rated yet | 0 |
In a striking, unexpected discovery, researchers at Albert Einstein College of Medicine of Yeshiva University have determined that vitamin C kills drug-resistant tuberculosis (TB) bacteria in laboratory culture. The finding ...
12 hours ago | 5 / 5 (5) | 0 |