Scientists Identify New Approaches to Treating PTSD

March 1, 2010

AUSTIN, Texas — Drugs known as HDAC inhibitors may prove useful in treating post-traumatic stress disorder (PTSD), according to a study conducted by faculty at The University of Texas at Austin's Waggoner Center for Alcohol and Addiction Research.

The study, the results of which were recently published in Neuropsychopharmacology, may point the way toward new treatments for PTSD, a severe anxiety disorder which is estimated to afflict as many as one in eight returning Iraq and Afghanistan War veterans.

"The HDAC inhibitors are already being used in clinical trials, but in relation to other neurological diseases, like Alzheimer's and Huntington's," says Igor Ponomarev, a research assistant professor in the College of Pharmacy and the Waggoner Center. "They've never been tested in PTSD. The results of this study suggest that they should be."

PTSD occurs as a result of exposure to severe stress—from battle, for example, or a natural disaster—and its symptoms, including flashbacks, an excessive startle response, depression, anxiety, and insomnia, can persist over long periods of time.

Researchers believe that PTSD occurs when the brain's system for regulating stress overloads to the point where it can no longer revert to a normal state, even after the cause of the stress disappears. Particularly affected is the amygdala, which is one of the critical structures in the brain related to learning and memory, and in particular to fear-related learning and memory.

Those suffering from PTSD can end up with an amygdala that is on high alert for mild stressors and stimuli that are evocative of the original source of the stress.

Ponomarev and co-author R. Adron Harris, professor of neurobiology, used a rat model of PTSD to trace these broad changes in the amygdala down to the level of gene expression.

"What we found were that genes that are known to be involved in excitation and inhibition changed their expression three weeks after stress," says Ponomarev. "The overall result is an amygdala that's unable to normally respond to stressors."

One of the most potentially useful findings of the study is that severe stress—like the kind that produces PTSD—can result in the increased expression of certain genetic elements that had, until recently, been dismissed by neuroscientists as "junk DNA."

These particular DNA sequences may prove significant, says Ponomarev, because they seem to be involved in, or indicative of, a process known as "chromatin remodeling," which helps determine which genes are or are not expressed in a given cell. It's precisely this process that seems to be responsive to the HDAC inhibitors.

"It's a hot area in neuropsychiatric disorders," he says, "because there are some pharmacological compounds that can block or promote chromatin remodeling. It's possible to imagine that some of the long-term changes in gene expression, which we've seen result from severe stress, could be reversed or modulated by the drugs."

For more information, contact: Daniel Oppenheimer, Hogg Foundation, 512 745 3353; Igor Ponomarev, Waggoner Center for Alcohol and Addiction Research, 512-471-5122.

6 Comments to "Scientists Identify New Approaches to Treating PTSD"

1.  Angela Peacock said on March 3, 2010

Thank you for researching PTSD. It seems that every treatment out there is not working, and we need all the research we can get in this area.

Iraq Veteran/PTSD

2.  Carl Whitmire said on March 4, 2010

FYI - The minister of my church here in Atlanta, Ga. is an ex-military chaplain and is heavily involved in helping our military, particularly in the area of suicide while serving. I forwarded him this article, for his benefit and work in this area. His name is Robert Certain, of St. Peter and St. Paul Episcopal Church in Marietta, Ga. I hope that between the two of your efforts, and thousands of others', that you can help our soldiers who are serving our country, and may need your help. Good luck to you. Carl Whitmire (UT '76)

3.  Justin Springer said on March 5, 2010

Great article and continued success to the researchers at UT. For those interested in more on PTSD and traumatic brain injury in the veteran population, check out the documentary film "Along Recovery" at http://www.alongrecovery.com. The film chronicles the recovery process of four soldiers recovering from traumatic brain injury and PTSD at the Brooke Army Medical Center in San Antonio.

4.  Chuck Yarling said on March 7, 2010

I welcome investigation into and positive results from any study on PTSD. My life changed after a rocket attack in Vietnam (1970): excessive startle response on which current medication "takes the edge off" but does not totally remove my reaction from sudden noises; and the need to wear ear plugs whenever I go out in public because of an extreme sensitivity to any volume of noise that would not bother most people. It would be nice to not be affected by these responses.

Chuck Yarling (UT '68 & '76)

5.  Katie Edwards said on March 8, 2010

I'm so encouraged by this new approach. My husband did two (12 months-plus) tours of Iraq and was recently diagnosed with PTSD. It is impossible for us to go anywhere with more than a handful of people around without him becoming extremely agitated and irritable, the jumping throughout his sleep at night and explosive anger and violence, just to name a few things. He is beginning treatment through the VA. I'm happy to hear that there may be more promising paths of treatment soon.

Thank you to all who have served and to UT for their continued excellence in research!

Katie Edwards (UT '03)

6.  Eric Greenstein said on March 13, 2010

This was well thought out and quite informative. I write on addiction, treatment and chemical dependency, and I'm hard to impress...but you have done an excellent job.