Health
Simple blood test diagnoses Parkinson's disease long before symptoms appear — A new research report appearing in the December issue of the FASEB Journal (http://www.fasebj.org) shows how scientists from the United Kingdom have developed a simple blood test to…
Early sign of Alzheimer's reversed in lab — One of the earliest known impairments caused by Alzheimer's disease - loss of sense of smell - can be restored by removing a plaque-forming protein in a mouse model of the disease,…
Parental controls on embryonic development? — When a sperm fertilises an egg, each contributes a set of chromosomes to the resulting embryo, which at these very early stages is called a zygote. Early on, zygotic genes are inert,…
Newly discovered heart stem cells make muscle and bone — Researchers have identified a new and relatively abundant pool of stem cells in the heart. The findings in the December issue of Cell Stem Cell, a Cell Press publication, show that…
BUSM researchers develop blood test to detect membranous nephropathy — Research conducted by a pair of physicians at Boston University School of Medicine (BUSM) and Boston Medical Centre (BMC) has led to the development of a test that can help diagnose…
New hip implants no better than traditional implants — New hip implants appear to have no advantage over traditional implants, suggests a review of the evidence published on bmj.com today…
Action needed to improve men's health in Europe — Policies aimed specifically at men are urgently needed to improve the health of Europe's men, say experts on bmj.com today…
Probiotics reduce infections for patients in intensive care — Traumatic brain injury is associated with a profound suppression of the patient's ability to fight infection. At the same time the patient also often suffers hyper-inflammation, due…
High blood sugar levels in older women linked to colorectal cancer — Elevated blood sugar levels are associated with an increased risk of colorectal cancer, according to a study led by researchers at Albert Einstein College of Medicine of Yeshiva University.…
Engineered botulism toxins could have broader role in medicine — The most poisonous substance on Earth - already used medically in small doses to treat certain nerve disorders and facial wrinkles - could be re-engineered for an expanded role in helping…
Where am I? > Home > News > Health

Sodium plays key role in tissue regeneration

Science Centric | 29 September 2010 17:26 GMT
Printable version A clip for your blog or website E-mail the story to a friend
Bookmark or share the story on your social network Vote for this article Decrease text size Increase text size
DON'T MISS —
The battle for CRTC2: How obesity increases the risk for diabetes
The battle for CRTC2: How obesity increases the risk for diabetes — Obesity is probably the most important factor in the development of insulin resistance, but science's understanding of the…
Cancer: The cost of being smarter than chimps?
Cancer: The cost of being smarter than chimps? — Are the cognitively superior brains of humans, in part, responsible for our higher rates of cancer? That's a question that…
More Health

Sodium gets a bad rap for contributing to hypertension and cardiovascular disease. Now biologists at Tufts University's School of Arts and Sciences have discovered that sodium also plays a key role in initiating a regenerative response after severe injury. The Tufts scientists have found a way to regenerate injured spinal cord and muscle by using small molecule drugs to trigger an influx of sodium ions into injured cells.

The approach breaks new ground in the field of biomedicine because it requires no gene therapy; can be administered after an injury has occurred and even after the wound has healed over; and is bioelectric, rather than chemically based.

In a paper appearing as the cover story of the September 29, 2010, issue of the Journal of Neuroscience, the Tufts team reported that a localised increase in sodium ions was necessary for young Xenopus laevis tadpoles to regenerate their tails - complex appendages containing spinal cord, muscle and other tissue.

Like human beings, who regenerate fingertips only as children, these tadpoles lose the ability to regenerate their tail with age. Most remarkably, it was shown that such 'refractory' tadpoles whose tails had been removed could be induced to make a perfect new tail by only an hour of treatment with a specific drug cocktail.

The findings have tremendous implications for treating wounds sustained in war as well as accidental injuries. The treatment method used is most directly applicable to spinal cord repair and limb loss, which are highly significant medical problems world-wide. It also demonstrates a proof-of-principle that may be applicable to many complex organs and tissues.

'We have significantly extended the effective treatment window, demonstrating that even after scar-like wound covering begins to form, control of physiological signals can still induce regeneration. Artificially causing an influx of sodium for just one hour can overcome a variety of problems, such as the decline in regenerative ability that comes with age and the effect of regeneration-blocking drugs,' said Tufts Professor of Biology Michael Levin, Ph.D., corresponding author on the paper and director of the Centre for Regenerative and Developmental Biology at Tufts. Co-authors were Research Associate Ai-Sun Tseng, Postdoctoral Associate Wendy S. Beane, Research Associate Joan M. Lemire, and Alessio Masi, a former post-doctoral associate in Levin's laboratory.

The transport of ions in and out of cells is regulated by electronic security doors, or gates, that let in specific ions under certain circumstances. A role for sodium current in tissue regeneration had been proposed in the past, but this is the first time the molecular-genetic basis of the ion flow has been identified, and a specific drug-based treatment demonstrated. Until now, advances in this model system had involved administering therapies before the injury was sustained.

'This is a novel, biomedically-relevant approach to inducing regeneration of a complex appendage,' noted Levin.

The Tufts research established a novel role in regeneration for the sodium channel Nav1.2, a crucial component of nerve and cardiac function. It showed that local, early increase in intracellular sodium is required for initiating regeneration following Xenopus tail amputation, while molecular and pharmacological inhibition of sodium transport causes regenerative failure. The new treatment induced regeneration only of correctly-sized and patterned tail structures and did not generate ectopic or other abnormal growth.

'The ability to restore regeneration using a temporally-controllable pharmacological approach not requiring gene therapy is extremely exciting,' said the researchers.

Of critical importance, they said, was the discovery that the tail could be induced to regenerate as late as 18 hours after amputation, revealing that tissues normally fated for regenerative failure still maintain their intrinsic characteristics and can be programmed to reactivate regeneration.

Amphibians such as frogs can restore organs lost during development, including the lens and tail. The frog tail is a good model for human regeneration because it repairs injury in the same way that people do: each tissue makes more of itself. (In contrast, regeneration in some other animals occurs through transdifferentiation (one cell type turns into another cell type) or adult stem cell differentiation. Furthermore, though small, the Xenopus larval tail is complex, with muscle, spinal cord, peripheral nerves and vasculature cells.

Source: Tufts University


Leave a comment
The details you provide on this page [e-mail address] will not be used to send unsolicited e-mail, and will not be supplied to a third party! Please note that we can not promise to give everyone a response. Comments are fully moderated. Once approved they will be posted within 24 hours.
Expand the form to leave a comment

RSS FEEDS, NEWSLETTER
Find the topic you want. Science Centric offers several RSS feeds for the News section.

Or subscribe for our Newsletter, a free e-mail publication. It is published practically every day.

Study gives clues to how adrenal cancer formsStudy gives clues to how adrenal cancer forms

— At the ends of chromosome are special pieces of DNA called telomeres. Think of it as the little tip that caps off a shoelace. The telomeres send signals to the cells…

New centre aims to improve recovery of soldiers with severe injuriesNew centre aims to improve recovery of soldiers with severe injuries

— When a soldier is wounded during combat, surgeons must focus on reducing infection and reconstructing damaged bone and tissues. Technologies that could improve the…

Products may revolutionise how men monitor their reproductive statusProducts may revolutionise how men monitor their reproductive status

— A medical home test kit based on a protein discovered at the University of Virginia Health System - SpermCheck Vasectomy - has begun shipping to zip codes across…

'Whose turn to pay?' can be deal-breaker for cohabiting couples'Whose turn to pay?' can be deal-breaker for cohabiting couples

— Couples living together face dozens of spending decisions every week. Should we eat out tonight? Whose turn to pay? Should we hire a lawnmower or a house cleaner,…

Popular tags in Health: cancer · diabetes · malaria · obesity