Featured Research

from universities, journals, and other organizations

Newts Regrow Hearts: Scientists Reveal Molecular Details Of Regeneration In Amphibians

Date:
December 5, 2006
Source:
Max-Planck-Gesellschaft
Summary:
When a newt loses a limb, the limb regrows. What is more, a newt can also completely repair damage to its heart. Scientists at the Max Planck Institute for Heart and Lung Research in Bad Nauheim have now started to decode the cellular mechanisms in this impressive ability to regenerate and have discovered the remarkable plasticity of newt heart cells. As mammals, and therefore also humans, do not have this ability, the findings could contribute to new cell therapies for patients with damaged organs (Journal of Cell Science, 2006).

Notophthalmus viridescens, the red-spotted newt.
Credit: Image : Max Planck Institute for Heart and Lung Research

When a newt loses a limb, the limb regrows. What is more, a newt can also completely repair damage to its heart. Scientists at the Max Planck Institute for Heart and Lung Research in Bad Nauheim have now started to decode the cellular mechanisms in this impressive ability to regenerate and have discovered the remarkable plasticity of newt heart cells. As mammals, and therefore also humans, do not have this ability, the findings could contribute to new cell therapies for patients with damaged organs (Journal of Cell Science, 2006).

The red-spotted newt, Notophthalmus viridescens, is a favourite animal of the researchers working with Thomas Braun in Nauheim. This amphibian comes from the wetlands of North America, but it also feels quite at home in the Institute’s aquaria. It is a small animal that scientists find interesting for a particular reason: whereas humans cannot regenerate damaged heart muscle adequately after a heart attack and the destroyed muscle tissue scars over instead, following damage, a newt’s heart can be completely repaired and the organ’s function can be completely restored.

The key to this ability to regenerate are the heart muscle cells themselves. When a newt’s heart sustains damage, its cells can lose their characteristic properties; they can dedifferentiate. The researchers were able to show that proteins typical of heart muscle cells - the heavy myosin chain and various troponins - were dramatically down-regulated in this process. At the same time, the cells embark on massive cell division to build up new heart muscle. It takes around two weeks for the heart function to be restored in the newt. The data shows that at this point the expression of the muscle-specific proteins is again normal, i.e. the cells have differentiated again, and have regained their characteristic properties.

The researchers isolated the heart muscle cells and cultured them. In most of the cells, Braun and his colleagues were able to demonstrate the existence of a protein called Phospho-H3. This protein is a marker for the G2 phase of the cell cycle and indicates that the newt heart regenerates without the involvement of stem cells. It also seems that the heart regeneration does not create typical wound healing tissue, called a blastema. Braun explains this finding: "The heart only has a relatively small number of different cell types. This could be a reason why the regeneration of heart tissue does not require a blastema." The researchers in Bad Nauheim found no indication that stem cells were involved in repairing newt hearts.

The process of regenerating lost extremities is different. Unlike in the process with the heart, newts develop a blastema in this case. Blastema cells have certain characteristics in common with stem cells, such as the development into different cell types. The cell biologists in Bad Nauheim injected isolated heart muscle cells into a newt’s leg that was regrowing after amputation. In this environment, the cells began to de-differentiate, as they did in the heart. However, this did not happen when they were injected into an undamaged extremity. Again, the researchers registered the very rapid loss of heart muscle-specific proteins.

"We suspect that the signal for the de-differentiation comes from the area where the wound is healing and the cells communicate with each other," explains Braun. These signals could be transmitted via certain enzymes, for example. An enzyme of this nature - focal adhesion kinase -, which plays a part in the transmission of signals in the cells, is phosphorylated in the transplanted cells and is thus active. The Max Planck researchers in Bad Nauheim hope that better understanding of the molecular issues involved in regeneration in the newt will open up new possibilities for the repairing human patients’ damaged hearts.


Story Source:

The above story is based on materials provided by Max-Planck-Gesellschaft. Note: Materials may be edited for content and length.


Cite This Page:

Max-Planck-Gesellschaft. "Newts Regrow Hearts: Scientists Reveal Molecular Details Of Regeneration In Amphibians." ScienceDaily. ScienceDaily, 5 December 2006. <www.sciencedaily.com/releases/2006/12/061205112423.htm>.
Max-Planck-Gesellschaft. (2006, December 5). Newts Regrow Hearts: Scientists Reveal Molecular Details Of Regeneration In Amphibians. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2006/12/061205112423.htm
Max-Planck-Gesellschaft. "Newts Regrow Hearts: Scientists Reveal Molecular Details Of Regeneration In Amphibians." ScienceDaily. www.sciencedaily.com/releases/2006/12/061205112423.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins