Close-range blast exposure & neurodegenerative processes among those with genetic risk for AD

June 24, 2019

(Boston)--A new study raises the possibility that close-range blast exposure among veterans with a genetically higher risk for Alzheimer's disease (AD), may make them more susceptible to degradation of their white matter, the part of the brain made of fiber connections called axons that connect nerve cells.

Although there is evidence that genetic risk for AD may elevate the risk of neurodegeneration following traumatic brain injury, it has been unknown if blast exposure also interacts with AD disease risk to promote neurodegeneration.

Researchers examined whether apolipoprotein (APOE) ε4, a well-known genetic risk factor for AD, influenced the relationship between close-range blast exposure (approximately 10 yards) and white matter integrity in a group of 200 Iraq and Afghanistan War veterans.

"We found that veterans who had close-range blast exposure and carried the ε4 allele had more spatially diffused white matter abnormalities than those without the ε4 allele," explained corresponding author Danielle R. Sullivan, PhD, a research health science specialist at the National Center for PTSD, VA Boston Healthcare System and assistant professor of psychiatry at Boston University School of Medicine. According to Sullivan this interaction remained significant after controlling for traumatic brain injury, pointing to the specificity of close-range blast exposure and APOE in white matter disruptions.

The researchers believe this study has implications for the long-term health effects of veterans returning from the Iraq and Afghanistan Wars. "It suggests that veterans who experienced a blast exposure within close-range and have elevated genetic risk for neurodegenerative disease may be at a greater risk for neurodegeneration and subsequent presentation of neurodegenerative diseases such as Alzheimer's disease."

Research has shown that repetitive and sub-concussive injuries without apparent acute symptoms are especially important in neurodegenerative processes. "Therefore, it is possible that close-range blast exposure, particularly when combined with genetic risk for neurodegenerative disease, may be a sensitive marker for sub-clinical but persistent effects on the brain related to potential neurodegenerative processes."
-end-
These findings appear in the Journal of Neurotrauma.

This work was supported by Career Development Award (grant number: 1 IK2 CX001772-01) from the United States Department of Veterans Affairs, Clinical Science Research and Development Service awarded to DRS and the Translational Research Center for TBI and Stress Disorders (TRACTS), a VA Rehabilitation Research and Development National Network Research Center (B9254-C). This work was further supported with resources and the use of facilities at the National Center for PTSD, the Neuroimaging Research for Veterans Center, VA Boston Healthcare System, and the Pharmacogenomics Analysis Laboratory Research and Development Service, Central Arkansas VA Healthcare System, Little Rock, Arkansas.

Boston University School of Medicine

Related Traumatic Brain Injury Articles from Brightsurf:

Point-of-care biomarker assay for traumatic brain injury
Intracranial abnormalities on CT scan in patients with traumatic brain injury (TBI) can be predicted by glial fibrillary acidic protein (GFAP) levels in the blood.

Long-studied protein could be a measure of traumatic brain injury
WRAIR scientists have recently demonstrated that cathepsin B, a well-studied protein important to brain development and function, can be used as biomarker, or indicator of severity, for TBI.

Reducing dangerous swelling in traumatic brain injury
After a traumatic brain injury (TBI), the most harmful damage is caused by secondary swelling of the brain compressed inside the skull.

Blue light can help heal mild traumatic brain injury
Daily exposure to blue wavelength light each morning helps to re-entrain the circadian rhythm so that people get better, more regular sleep which was translated into improvements in cognitive function, reduced daytime sleepiness and actual brain repair.

Dealing a therapeutic counterblow to traumatic brain injury
A team of NJIT biomedical engineers are developing a therapy which shows early indications it can protect neurons and stimulate the regrowth of blood vessels in damaged tissue.

Predictors of cognitive recovery following mild to severe traumatic brain injury
Researchers have shown that higher intelligence and younger age are predictors of greater cognitive recovery 2-5 years post-mild to severe traumatic brain injury (TBI).

Which car crashes cause traumatic brain injury?
Motor vehicle crashes are one of the most common causes of TBI-related emergency room visits, hospitalizations and deaths.

Traumatic brain injury and kids: New treatment guidelines issued
To help promote the highest standards of care, and improve the overall rates of survival and recovery following TBI, a panel of pediatric critical care, neurosurgery and other pediatric experts today issued the third edition of the Brain Trauma Foundation Guidelines for the Management of Pediatric Severe TBI.

Addressing sleep disorders after traumatic brain injury
Amsterdam, NL, December 10, 2018 - Disorders of sleep are some of the most common problems experienced by patients after traumatic brain injury (TBI).

Rutgers researchers discover possible cause for Alzheimer's and traumatic brain injury
Rutgers researchers discover a possible cause for Alzheimer's and traumatic brain injury, and the new mechanism may have also led to the discovery of an effective treatment.

Read More: Traumatic Brain Injury News and Traumatic Brain Injury Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.