Matters of the Head and the Heart

Feb. 19, 2014

3 Bullets:

• Previous links between posttraumatic stress disorder (PTSD) and cardiovascular disorders were mostly thought to be psychological.
• Using mouse models, researchers at ISB and U.S. Army Center for Environmental Health Research found physical injury of heart tissue as a result of exposure to stressful environments.
• This research is important for developing future methods for early and objective diagnosis, and new therapeutic approaches for patients with PTSD and PTSD-associated ailments.

By Hillary Lauren

In a study published online on Feb. 10 in the Proceedings of the National Academies of Science (PNAS), researchers at the Institute for Systems Biology and the U.S. Army Center for Environmental Health Research present molecular evidence that exposure to conditions similar to that experienced in post-traumatic stress disorder (PTSD) can cause heart tissue damage in mice.

Journal: PNAS, Feb. 10, 2014
Title: Molecular evidence of stress-induced acute heart injury in a mouse model simulating post traumatic stress disorder (link to paper)
Authors: Ji-Hoon Cho, Inyoul Lee, Rasha Hammamieh, Kai Wang, David Baxter, Kelsey Scherler, Alton Etheridge, Alena Kulchenko, Aarti Gautam, Seid Muhie, Nabarun Chakraborty, David J. Galas, Marti Jett, and Leroy Hood.

PTSD can develop as a result of experiencing one or more traumatic events, such as natural disasters, physical assault and a military combat environment. Affecting about 7 percent of the population in the United States, PTSD is one of the most common psychological conditions. Patients with PTSD have a higher risk of cardiovascular conditions, including high blood pressure, elevated cholesterol levels and stroke.

Previously, heart disorders related to PTSD were mostly thought to be anxiety-induced. Similarly, in the condition known as Da Costa syndrome (or “soldier’s heart” reported during the American Civil War), patients display symptoms of heart disorders such as palpitations and chest pain but show no apparent physical abnormalities upon examination.

ISB researchers used a systems approach to study how stress affects organs such as the heart in a PTSD mouse model. After the researchers paired subservient mice with aggressive mice, the socially-stressed mice displayed symptoms similar to PTSD patients, including avoidance behavior, weight gain and decreased memory. Further examinations of gene expression from heart tissues in the social defeated mice revealed increased cellular processes related to immune responses and active tissue repair.

Future research interests include investigating the long-term effects of stress and genetic factors involved in stress-associated heart injury. Using this PTSD mouse model may also lead to developing methods for early diagnosis and insights on therapeutic approaches for treatment.