Scientists surprised to discover lymphatic 'scavenger' brain cells

May 01, 2017

The brain has its own inbuilt processes for mopping up damaging cellular waste -- and these processes may provide protection from stroke and dementia.

University of Queensland scientists discovered a new type of lymphatic brain "scavenger" cell by studying tropical freshwater zebrafish -- which share many of the same cell types and organs as humans.

Lead researcher Associate Professor Ben Hogan from UQ's Institute for Molecular Bioscience said the fundamental discovery would help scientists understand how the brain forms and functions.

"It is rare to discover a cell type in the brain that we didn't know about previously, and particularly a cell type that we didn't expect to be there," he said.

"The brain is the only organ without a known lymphatic system, so the fact that these cells are lymphatic in nature and surround the brain makes this finding quite a surprise.

"These cells appear to be the zebrafish version of cells described in humans called "mato" or lipid laden cells, which clear fats and lipids from the system but were not known to be lymphatic in nature.

"When wastes such as excess fats leak out of the bloodstream, it is the job of the lymphatic system to clean them out to avoid damaging our organs."

Dr Hogan said the study focused on the presence and development of "scavenger" cells in zebrafish, however there was good reason to believe that equivalent cells surrounded and protected the human brain from a build-up of cellular waste.

"Zebrafish are naturally transparent, which means we can use advanced light microscopes to see directly into the zebrafish brain," Dr Hogan said.

"Examining the zebrafish brain up close allowed us to find these cells and see how they form and function in detail.

"Normally, lymphatic endothelial cells will group together to form lymphatic vessels to carry fluid, but impressively, in the adult zebrafish brain these cells exist individually, independent of vessels and collect waste that enter the brain from the bloodstream.

"Our focus now is to investigate how these cells function in humans and see if we can control them with existing drugs to promote brain health, and improve our understanding of neurological diseases such as stroke and dementia."
-end-
The study was published today in Nature Neuroscience (DOI: 10.1038/nn.4558) and involved researchers from UQ's Institute for Molecular Bioscience, The University of Melbourne, Monash University and Japan's National Cerebral and Cardiovascular Centre.

The National Health and Medical Research Council and UQ funded the research.

Media: Gemma Ward, IMB Communications, 07 3346 2155, 0439 651 107, communications@imb.uq.edu.au

University of Queensland

Related Stroke Articles from Brightsurf:

Stroke alarm clock may streamline and accelerate time-sensitive acute stroke care
An interactive, digital alarm clock may speed emergency stroke care, starting at hospital arrival and through each step of the time-sensitive treatment process.

Stroke patients with COVID-19 have increased inflammation, stroke severity and death
Stroke patients who also have COVID-19 showed increased systemic inflammation, a more serious stroke severity and a much higher rate of death, compared to stroke patients who did not have COVID-19, according a retrospective, observational, cross-sectional study of 60 ischemic stroke patients admitted to UAB Hospital between late March and early May 2020.

'Time is vision' after a stroke
University of Rochester researchers studied stroke patients who experienced vision loss and found that the patients retained some visual abilities immediately after the stroke but these abilities diminished gradually and eventually disappeared permanently after approximately six months.

More stroke awareness, better eating habits may help reduce stroke risk for young adult African-Americans
Young African-Americans are experiencing higher rates of stroke because of health conditions such as high blood pressure, diabetes and obesity, yet their perception of their stroke risk is low.

How to help patients recover after a stroke
The existing approach to brain stimulation for rehabilitation after a stroke does not take into account the diversity of lesions and the individual characteristics of patients' brains.

Kids with headache after stroke might be at risk for another stroke
A new study has found a high incidence of headaches in pediatric stroke survivors and identified a possible association between post-stroke headache and stroke recurrence.

High stroke impact in low- and middle-income countries examined at 11th World Stroke Congress
Less wealthy countries struggle to meet greater need with far fewer resources.

Marijuana use might lead to higher risk of stroke, World Stroke Congress to be told
A five-year study of hospital statistics from the United States shows that the incidence of stroke has risen steadily among marijuana users even though the overall rate of stroke remained constant over the same period.

We need to talk about sexuality after stroke
Stroke survivors and their partners are not adequately supported to deal with changes to their relationships, self-identity, gender roles and intimacy following stroke, according to new research from the University of Sydney.

Standardized stroke protocol can ensure ELVO stroke patients are treated within 60 minutes
A new study shows that developing a standardized stroke protocol of having neurointerventional teams meet suspected emergent large vessel occlusion (ELVO) stroke patients upon their arrival at the hospital achieves a median door-to-recanalization time of less than 60 minutes.

Read More: Stroke News and Stroke 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.