Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

"Catch-up" Growth Signals Revealed

31.01.2011
University of Michigan researchers have uncovered molecular signals that regulate catch-up growth---the growth spurt that occurs when normal conditions are restored after a fetus, young animal or child has been ill, under stress or deprived of enough food or oxygen to grow properly.

The results, published in the Feb. 15 issue of the journal Development, could lead to better understanding of why babies who undergo catch-up growth are at higher risk in later life for diabetes, cardiovascular disease, obesity and other health problems.

"Catch-up growth is a widespread phenomenon in the animal kingdom, from humans down to little fish and worms," said Cunming Duan, U-M professor of molecular, cellular and developmental biology. "But biologists have known very little about the molecular signals that coordinate this phenomenon."

Duan and co-workers suspected that a group of hormones called insulin-like growth factors (IGFs)---known to be important in normal growth and development and also implicated in cancer and aging---might be involved. Like other peptide and protein hormones, IGFs work by binding to receptors on the cells they target. The binding then sets off a cascade of reactions that ultimately direct the cell to do something.

"Since we were dealing with a type of growth, it made sense to look at the main growth regulators," Duan said.

Also, in research published in 2010, Duan's group found that altering oxygen levels in muscle cells changed the chemical signal of IGF. Knowing that catch-up growth can be triggered by changing oxygen levels, the researchers reasoned that IGF might mediate the process.

Using zebrafish as a model system, Duan's group did a series of experiments. First, they simply monitored growth and IGF signaling in fish embryos grown in water in which the oxygen concentration was reduced for a time and then restored. As expected, growth was suppressed when oxygen was low, but the fish caught up with a growth spurt when oxygen was restored to normal levels. Interestingly, IGF signals changed in concert with oxygen levels.

Next the researchers repeated the low-oxygen, normal-oxygen experiment with a different twist: They blocked IGF signaling in the fish embryos, using either genetic methods or pharmacological inhibitors.

"We found that if you block IGF signaling, the animal cannot catch up," Duan said. "From this we learned that the IGF signal is not only changing, but that the change is really necessary for the animal to catch up."

Duan's group went on to investigate the specific biochemical pathways involved. They found that one, called the MAP kinase pathway, is critical for catch-up growth. However, it may not be the only pathway that figures in, and the specific pathway used may depend on circumstances.

"You can think of it like your route to work. Maybe you normally take I-94, but if it's blocked, you use other routes that you normally don't use," Duan said.

In future research, Duan's group wants to explore the long-term effects of changes in the IGF-MAP kinase pathway that are related to catch-up growth.

"If we find lasting changes, we may be able to figure out ways of intervening to reduce the risk of associated health problems that develop later in life," Duan said.

In addition to Duan, the paper's authors are postdoctoral fellow Hiroyasu Kamei, former postdoctoral fellow Yonghe Ding, former graduate student Shingo Kajimura, graduate student Michael Wells and former undergraduate student Peter Chiang.

Funding was provided by the National Science Foundation and the Japan Society for Promotion of Science Fellowship program.

Cunming Duan: www.mcdb.lsa.umich.edu/faculty_cduan.html

Developmen: http://dev.biologists.org

Nancy Ross-Flanigan | Newswise Science News
Further information:
http://www.umich.edu
http://dev.biologists.org

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>