Researchers have discovered mechanism that could, in the future, lead to new treatments for anxiety disorders.
Glo1 gene numbers are said to be responsible for increased levels of anxiety. Scientists claim that lowering levels of Glo1 or increasing levels of methylglyoxal (MG) could reduce anxiety behaviors.
"Animals transgenic for Glo1 had different levels of anxiety-like behavior, and more copies made them more anxious. We showed that Glo1 was causally related to anxiety-like behavior, rather than merely correlated,” said Abraham Palmer, PhD and senior author of the study in a University of Chicago press release.
To find out whether the number of Glo1 has any effect on anxiety, the scientists Margaret Distler and colleagues inserted two, eight or ten copies of GLO1 in mice. They then tested the levels of anxiety in these mice through open field tests.
As expected, higher number of Glo1 resulted in the mice being more withdrawn, showing symptoms of anxiety.
“It's the first study to show that it's the copy number variant that has the potential to change Glo1 expression and behavior. Our study was a physiological representation of what it means to increase Glo1 expression for anxiety," said Distler.
In the next stage of experiment, the researchers found that increasing the levels of Methylglyoxal eased these anxiety symptoms almost immediately.
“Methylglyoxal changed behavior within 10 minutes of administration, which means it's a rapid onset. It's not changing gene expression, and it's not having long-term downstream effects. That was our first breakthrough,” said Distler.
The scientists are hopeful that the discovery of this new mechanism will pave way for a new type of treatment in people whose lives are affected by anxiety or epilepsy or other psychiatric disorders.
Benzodiazepines and barbiturates are generally used to treat anxiety but these drugs have various side-effects. Scientists feel that the new approach could lower the risks, especially that of overdose.
"The GABA-A receptor agents already out there have a lot of side effects, such as sedation and hypothermia, as well as a high abuse liability. It’s possible that taking a Glo1 inhibitor will increase only MG levels to a certain maximum. You could have the potential for more specificity, given that you're activating a system that's already in place, not just dumping methylglyoxal or some other GABA-A receptor agent throughout the brain," Distler said.
Another study published in the Journal of Alternative and Complementary Medicine says that behavioral interventions like yoga can lower levels of anxiety in people and increase thalamic GABA levels.
"What's neat is that we started with exploratory, open-ended genetic studies in mice, and we've now gotten into some fundamental new physiology that nobody had appreciated or put together before. Now we're starting to reap some of the fruit from those types of genetic studies to enrich our understanding of more classical aspects of biology,” Palmer said.