Nav: Home

This gene could play a major role in reducing brain swelling after stroke

April 15, 2019

Could a medication someday help the brain heal itself after a stroke, or even prevent damage following a blow to the head? A new USC study lends support to the idea.

When a person has a stroke, the brain responds with inflammation, which expands the area of injury and leads to more disability. In the April 9 issue of Cell Reports, USC researchers describe a key gene involved with tamping down inflammation in the brain, as well as what happens when the injured brain gets an added boost of that gene.

The gene -- called TRIM9 -- is abundant in the youthful brain but grows scarce with age, just as people become more at risk from stroke. In a lab model of stroke, researchers found that older brains with low TRIM9 levels -- or engineered brains missing the TRIM9 gene entirely -- were prone to extensive swelling following stroke.

But when the scientists used a harmless virus to carry a dose of the gene directly into TRIM9-deficient brains, the swelling decreased dramatically and recovery improved.

Jae Jung, lead author and chair of the Department of Molecular Microbiology and Immunology at the Keck School of Medicine of USC, says it's unlikely that gene therapy delivered by viruses will become the go-to treatment for strokes, head injuries or encephalitis. It's too slow, he said, and the best shot at treating stroke is within the first 30 minutes to one hour. Jung says the next step will be identifying what, exactly, flips on the switch for TRIM9 gene expression.

"Maybe there will be a way to chemically activate TRIM9 right after a stroke," Jung said. "Or maybe a football player can take a medication that turns on TRIM9 gene expression right after they get a blow to the head."

Not all inflammation in the brain is bad, Jung added. Inflammation plays a role in fighting infection and helps clear away dead tissue. But when it goes on too long, neurons die; inflammation causes the brain's blood vessels to become permeable, allowing white blood cells to enter tissue where they don't belong.
-end-
In addition to Jung, the paper's other authors are Berislav Zlokovic and Zhen Zhao of the Zilkha Neurogenetic Institute at the Keck School; co-first authors Jianxiong Zeng and Yaoming Wang, Zhifei Luo Lin-Chun Chang, Ji Seung Yoo, Huan Yan, Younho Choi and Xiaochun Xie, all of the Keck School; Benjamin Deverman and Viviana Gradinaru of the California Institute of Technology; and Stephanie Gupton of the University of North Carolina at Chapel Hill.

The study was supported by the National Institutes of Health (grants CA200422, CA180779, DE023926, DE027888, DE28521, AI073099, AI116585, AI129496, AI140718, 9R01NS090904-16 and AI140705), the Hastings Foundation, the Fletcher Jones Foundation, the Alzheimer's Association (grant NIRG-15-363387), the Whittier Foundation, the Cure for Alzheimer's Fund (NS090904), Fondation Leducq Transatlantic Network of Excellence for the Study of Perivascular Spaces in Small Vessel Disease (reference 16 CVD 05 and GM108970), the Beckman Institute at Caltech through the Resource Center for CLARITY, Optogenetics and Vector Engineering, and an NIH Director's New Innovator Award (DP20D017782).

University of Southern California

Related Stroke Articles:

Retraining the brain to see after stroke
A new study out today in Neurology, provides the first evidence that rigorous visual training restores rudimentary sight in patients who went partially blind after suffering a stroke, while patients who did not train continued to get progressively worse.
Catheter ablations reduce risks of stroke in heart patients with stroke history, study finds
Atrial fibrillation patients with a prior history of stroke who undergo catheter ablation to treat the abnormal heart rhythm lower their long-term risk of a recurrent stroke by 50 percent, according to new research from the Intermountain Medical Center Heart Institute.
Imaging stroke risk in 4-D
A new MRI technique developed at Northwestern University detects blood flow velocity to identify who is most at risk for stroke, so they can be treated accordingly.
Biomarkers may help better predict who will have a stroke
People with high levels of four biomarkers in the blood may be more likely to develop a stroke than people with low levels of the biomarkers, according to a study published in the Aug.
Pre-stroke risk factors influence long-term future stroke, dementia risk
If you had heart disease risk factors, such as high blood pressure, before your first stoke, your risk of suffering subsequent strokes and dementia long after your initial stroke may be higher.
Intervention methods of stroke need to focus on prevention for blacks to reduce stroke mortality
Blacks are four times more likely than their white counterparts to die from stroke at age 45.
Study shows area undamaged by stroke remains so, regardless of time stroke is left untreated
A study led by Achala Vagal, M.D., associate professor at the University of Cincinnati College of Medicine and a UC Health radiologist, looked at a group of untreated acute stroke patients and found that there was no evidence of time dependence on damage outcomes for the penumbra, or tissue that is at risk of progressing to dead tissue but is still salvageable if blood flow is returned in a stroke, but rather an association with collateral flow -- or rerouting of blood through clear vessels.
Immediate aspirin after mini-stroke substantially reduces risk of major stroke
Using aspirin urgently could substantially reduce the risk of major strokes in patients who have minor 'warning' events.
SAGE launches the European Stroke Journal with the European Stroke Organisation
SAGE, a world leading independent and academic publisher, is delighted to announce the launch of the European Stroke Journal, the flagship journal of the European Stroke Organisation.
The S-stroke or I-stroke?
The year 2016 is an Olympic year. Developments in high-performance swimwear for swimming continue to advance, along with other areas of scientific research.

Related Stroke Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Changing The World
What does it take to change the world for the better? This hour, TED speakers explore ideas on activism—what motivates it, why it matters, and how each of us can make a difference. Guests include civil rights activist Ruby Sales, labor leader and civil rights activist Dolores Huerta, author Jeremy Heimans, "craftivist" Sarah Corbett, and designer and futurist Angela Oguntala.
Now Playing: Science for the People

#521 The Curious Life of Krill
Krill may be one of the most abundant forms of life on our planet... but it turns out we don't know that much about them. For a create that underpins a massive ocean ecosystem and lives in our oceans in massive numbers, they're surprisingly difficult to study. We sit down and shine some light on these underappreciated crustaceans with Stephen Nicol, Adjunct Professor at the University of Tasmania, Scientific Advisor to the Association of Responsible Krill Harvesting Companies, and author of the book "The Curious Life of Krill: A Conservation Story from the Bottom of the World".