(Press-News.org) The body's blood clot-busting enzymes are much busier than previously imagined, with new research showing that they also dispose of every cell that dies prematurely from disease or trauma.
In research published today in Cell Reports, scientists from Monash University have demonstrated for the first time the enzyme t-PA, which plays a vital role in the removal of blood clots, is also a major player in the removal of necrotic, or dead, cells.
Necrosis occurs when cells in living tissue die prematurely due to external stress or injury. The body's system for removing waste associated with necrotic cell removal was not, until now, well understood.
Professor Robert Medcalf and Dr Andre Samson, of the University's Australian Centre for Blood Diseases (ACBD), led the research with Professor Stephen Bottomley of the Monash Department of Biochemisty and Molecular Biology.
The research team found that in the late stages of death, the injured cell undergoes a restructure and takes on a form not unlike a blood clot, to prepare for efficient removal from the body. This process had never been described before.
Professor Medcalf said the blood clot-like structure allowed the damaged cells to be recognised and removed by t-PA and its enzymatic waste disposal team.
"It's exactly the same principle as the formation and removal of a blood clot," Professor Medcalf said.
"In the process of a cell dying it goes through this unique form of aggregation to keep all the intracellular debris localised. Then, it can be taken out in an orderly fashion by the blood clot-busting enzyme system without causing damage to the body."
The researchers were studying brain tissue when they made the discovery, but have shown that the same process applies to every cell in the body.
"It's very efficient. Instead of doubling up, the body is using the same disposal system to eliminate a variety of unwanted waste products, be they dead cells or blood clots that have served their purpose," Professor Medcalf said.
"What this means is that t-PA and its team of enzymes recognises waste through structure or shape, not by the specific proteins involved."
The findings shed further light on the function and therapeutic uses of t-PA, which is used in the treatment of stroke and heart attack.
Researchers from Alfred Health and the Ludwig Institute for Cancer Researchers also collaborated on the study, which was funded by the National Health and Medical Research Council of Australia.
### END
Clot-busting enzymes are working 2 jobs
2012-10-04
ELSE PRESS RELEASES FROM THIS DATE:
The smell of Mom: Scientists find elusive trigger of first suckling in mice
2012-10-04
LA JOLLA, CA – A team led by biologists at The Scripps Research Institute has solved the long-standing scientific mystery of how mice first know to nurse or suckle.
This basic mammalian instinct, which could be a key to understanding instinctive behavior more generally, was thought to be triggered by a specific odor (pheromone) that all mouse mothers emit. But, as described online ahead of print by the journal Current Biology on October 4, 2012, the trigger in mice turns out to be a more complicated blend of nature and nurture: a signature mix of odors, unique for each ...
In cancer, an embryonic gene-silencing mechanism gone awry
2012-10-04
There are some genes that are only activated in the very first days of an embryo's existence. Once they have accomplished their task, they are shut down forever, unlike most of our genes, which remain active throughout our lives. EPFL scientists have unveiled part of this strange mechanism. The same process, accidentally initiated later in life, could be responsible for many kinds of cancer. The discovery is described in a recent article in the journal Cell Reports.
The researchers identified a group of proteins that play a key role in this phenomenon. They bind to a ...
BWH researchers discover genetic risk for uterine fibroids
2012-10-04
BOSTON, MA—Uterine fibroids are the most common type of pelvic tumors in women and are the leading cause of hysterectomy in the United States. Researchers from Brigham and Women's Hospital (BWH) are the first to discover a genetic risk allele (an alternative form of a gene) for uterine fibroids in white women using an unbiased, genome-wide approach. This discovery will pave the way for new screening strategies and treatments for uterine fibroids.
The study will be published online on October 4, 2012 in The American Journal of Human Genetics.
The research team, led by ...
Study shows benefits, drawbacks, for women's incontinence treatments
2012-10-04
Oral medication for treating a type of incontinence in women is roughly as effective as Botox injections to the bladder, reported researchers who conducted a National Institutes of Health clinical trials network study, with each form of treatment having benefits and limitations.
After six months, women in both treatment groups said that the average number of daily episodes had declined from about five per day to about 1-2 per day.
In the study, the researchers compared the effectiveness of Botox injections to oral anticholinergic medications for treating urge urinary ...
Babies learn the smell of mum
2012-10-04
Researchers show for the first time that a mammal begins to suckle its mother's milk through a learned response built on learning her unique combination of smells. When it is born, the newborn is exposed to the smell of its mother's amniotic fluid and the baby then responds to those smells to feed.
Prevailing thought has been that pheromones –chemicals that trigger an innate behaviour – drove the suckling response as an automatic behaviour. The new work determines that, in mice, the smells must be learned before the behaviour can occur.
Suckling is a critical step for ...
New function of a protein involved in colon cancer is identified
2012-10-04
Researchers from IMIM, Hospital del Mar Medical Research Institute, have succeeded in determining the function of a new variant of enzyme IKKalpha (IKKα) to activate some of the genes taking part in the tumor progressions of colorectal cancer. In the future, this fact will make it possible to design new drugs that inhibit this enzyme specifically and are less toxic for the remaining body cells, hence improving the treatment for this disease.
The study is the culmination of previous research by the IMIM Research Group on Stem Cells and Cancer that had proven the ...
Penn researchers create a universal map of vision in the human brain
2012-10-04
PHILADELPHIA - Nearly 100 years after a British neurologist first mapped the blind spots caused by missile wounds to the brains of soldiers, Perelman School of Medicine researchers at the University of Pennsylvania have perfected his map using modern-day technology. Their results create a map of vision in the brain based upon an individual's brain structure, even for people who cannot see. Their result can, among other things, guide efforts to restore vision using a neural prosthesis that stimulates the surface of the brain. The study appears in the latest issue of Current ...
Better battlefield triage, transport may raise severely wounded soldiers' survival rates
2012-10-04
CHICAGO—Wounded soldiers who sustained chest injuries in Operation Enduring Freedom (Afghanistan) and Operation Iraqi Freedom (Iraq) had higher mortality rates than soldiers
in Korea and Vietnam, according to a military trauma study presented at the 2012 American College of Surgeons Annual Clinical Congress. However, better battlefield triage and transport may have meant that severely wounded soldiers whom would have been considered killed in
action in previous conflicts are more likely to get sent to trauma centers in the United States sooner in their course of care, ...
Chewing ability linked to reduced dementia risk
2012-10-04
Can you bite into an apple? If so, you are more likely to maintain mental abilities, according to new research from Karolinska Institutet in Sweden.
The population is ageing, and the older we become the more likely it is that we risk deterioration of our cognitive functions, such as memory, decision-making and problem solving. Research indicates several possible contributors to these changes, with several studies demonstrating an association between not having teeth and loss of cognitive function and a higher risk of dementia.
One reason for this could be that few ...
No evidence for 30-nm chromatin fibers in the mouse genome
2012-10-04
HEIDELBERG, 4 October 2012 – Scientists in Canada and the United States have used three-dimensional imaging techniques to settle a long-standing debate about how DNA and structural proteins are packaged into chromatin fibres. The researchers, whose findings are published in EMBO reports, reveal that the mouse genome consists of 10-nm chromatin fibres but did not find evidence for the wider 30-nm fibres that were previously thought to be important components of the DNA architecture.
"DNA is an exceptionally long molecule that can reach several metres in length. This means ...