Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

HKUST researchers discover ways to regenerate corticospinal tract axons

06.07.2015

Researchers at the Hong Kong University of Science and Technology (HKUST) have found a way to stimulate the growth of axons, which may spell the dawn of a new beginning on chronic SCI treatments.

Chronic spinal cord injury (SCI) is a formidable hurdle that prevents a large number of injured axons from crossing the lesion, particularly the corticospinal tract (CST). Patients inflicted with SCI would often suffer a loss of mobility, paralysis, and interferes with activities of daily life dramatically. While physical therapy and rehabilitation would help the patients to cope with the aftermath, axonal regrowth potential of injured neurons was thought to be intractable.


This sagittal section shows the regeneration of mouse corticospinal tract axons (red) 7 months after Pten deletion was initiated in motor cortex. Pten deletion was initiated 1 year after spinal cord injury in this mouse. Green labels glial fibrillary acidic protein.

Credit: Division of Life Science, HKUST

No outside stimulants are needed; the growth driver lies within the neurons themselves.

Inside our DNA, in particular.

In the July 1st issue of The Journal of Neuroscience, HKUST researchers report that the deletion of the PTEN gene would enhance compensatory sprouting of uninjured CST axons. Furthermore, the deletion up-regulated the activity of another gene, the mammalian target of rapamycin (mTOR), which promoted regeneration of CST axons. Axons transmit information to different neurons, muscles, and glands; as bundles they help make up nerves.

Led by Kai Liu, PhD, the study's senior author and assistant professor in life sciences at HKUST, the research team initiated PTEN deletion on mice after pyramidotomy. Similar treatment procedures were carried out on a 2nd group 4 months after severe spinal cord injuries, and a 3rd group after 12 months.

The team recorded a regenerative response of CST axons in all 3 samples--showing that PTEN deletion stimulates CST sprouting and regeneration, even though the injury was sustained a long time ago.

"As one of the long descending tracts controlling voluntary movement, the corticospinal tract (CST) plays an important role for functional recovery after spinal cord injury," says Professor Liu. "The regeneration of CST has been a major challenge in the field, especially after chronic injuries. Here we developed a strategy to modulate PTEN/mTOR signaling in adult corticospinal motor neurons in the post-injury paradigm."

"It not only promoted the sprouting of uninjured CST axons, but also enabled the regeneration of injured axons past the lesion in a mouse model of spinal cord injury, even when treatment was delayed up to 1 year after the original injury. The results considerably extend the window of opportunity for regenerating CST axons severed in spinal cord injuries.

Compared with acute injury, axons face more barriers to regenerate after chronic SCI. Previously, scientists have shown that Axon retraction may further increase the distance that axons need to travel; Extracellular matrices, which become well consolidated around the chronic lesion site, also increases inhibition. Neuronal aging may also add obstacles to regrowth. In light of all of these challenges, it is indeed surprising to find that CST axons can still regenerate after 1 year.

"It is interesting to find that chronically injured neurons retain the ability to reform tentative synaptic connections," says Liu. "PTEN inhibition can be targeted on particular neurons, which means that we can apply the procedure specifically on the region of interest as we continue our research."

###

This study was supported in part by the Hong Kong Research Grants Council Theme-Based Research Scheme (Grant T13-607/12R), the National Key Basic Research Program of China (Grant 2013CB530900), the Research Grants Council of Hong Kong Special Administrative Region (Grants AoE/M-09/12, HKUST5/CRF/12R, AoE/M-05/12, C4011-14R, 662011, 662012, 689913, and 16101414), and the Hong Kong Spinal Cord Injury Fund.

Media Contact

Anita Lam
Anitalam@ust.hk
852-235-86313

http://www.ust.hk 

Anita Lam | EurekAlert!

More articles from Life Sciences:

nachricht Plant escape from waterlogging
17.10.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Study suggests oysters offer hot spot for reducing nutrient pollution
17.10.2017 | Virginia Institute of Marine Science

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

Im Focus: New nanomaterial can extract hydrogen fuel from seawater

Hybrid material converts more sunlight and can weather seawater's harsh conditions

It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Study suggests oysters offer hot spot for reducing nutrient pollution

17.10.2017 | Life Sciences

Breaking: the first light from two neutron stars merging

17.10.2017 | Physics and Astronomy

World first for reading digitally encoded synthetic molecules

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>