Project 3

PET/MRI of the brain-hematopoiesis-atherosclerosis axis in PTSD patients

Atherosclerosis’ clinical consequences, including myocardial infarction (MI) and stroke, are the most common causes of death worldwide. Lipid accumulation and associated inflammatory processes promote atherosclerosis progression. Investigators from Projects 1 and 2 observed that chronic psychosocial stress accelerates hematopoiesis and promotes inflammation in atherosclerotic mice. This discovery illuminates a potentially important mechanism that gives rise to systemic inflammation. Whether emotional stress similarly influences this hematopoietic pathway in humans remains unknown. PTSD, a serious stress disorder triggered by exposure to extreme traumatic events, is associated with elevated circulating inflammation markers and higher risk for MI. PTSD patients therefore provide a unique opportunity to study the mechanisms linking chronic psychosocial stress and atherosclerosis.

This Project will investigate the mechanisms that link PTSD and inflammatory atherosclerosis. We will combine innovative PET with magnetic resonance imaging (PET/MRI) to simultaneously study the hematopoietic system, the artery wall, and the brain’s fear system to elucidate the relationship between psychosocial stress and systemic inflammation/atherosclerosis in: I) individuals with PTSD whose traumatic event occurred at least one year prior to enrollment, II) individuals without PTSD who have time-matched exposure to severe psychosocial trauma, and III) matched volunteers with neither PTSD nor trauma exposure.  A total of 240 participants, allocated to the three 80-subject study groups, will be recruited in New York and Boston. This research will be conducted at ISMMS and MGH.

Specific Aims:

  • Aim 1: To investigate atherosclerotic inflammation and burden in PTSD using PET/MRI
  • Aim 2: To investigate relationships among brain, hematopoietic organs, and vascular inflammation