Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Down syndrome neurons grown from stem cells show signature problems

28.05.2013
Down syndrome, the most common genetic form of intellectual disability, results from an extra copy of one chromosome.

Although people with Down syndrome experience intellectual difficulties and other problems, scientists have had trouble identifying why that extra chromosome causes such widespread effects.

In new research published this week, Anita Bhattacharyya, a neuroscientist at the Waisman Center at the University of Wisconsin-Madison, reports on brain cells that were grown from skin cells of individuals with Down syndrome.

"Even though Down syndrome is very common, it's surprising how little we know about what goes wrong in the brain," says Bhattacharyya. "These new cells provide a way to look at early brain development."

The study began when those skin cells were transformed into induced pluripotent stem cells, which can be grown into any type of specialized cell. Bhattacharyya's lab, working with Su-Chun Zhang and Jason Weick, then grew those stem cells into brain cells that could be studied in the lab.

One significant finding was a reduction in connections among the neurons, Bhattacharyya says. "They communicate less, are quieter. This is new, but it fits with what little we know about the Down syndrome brain." Brain cells communicate through connections called synapses, and the Down neurons had only about 60 percent of the usual number of synapses and synaptic activity. "This is enough to make a difference," says Bhattacharyya. "Even if they recovered these synapses later on, you have missed this critical window of time during early development."

The researchers looked at genes that were affected in the Down syndrome stem cells and neurons, and found that genes on the extra chromosome were increased 150 percent, consistent with the contribution of the extra chromosome.

However, the output of about 1,500 genes elsewhere in the genome was strongly affected. "It's not surprising to see changes, but the genes that changed were surprising," says Bhattacharyya. The predominant increase was seen in genes that respond to oxidative stress, which occurs when molecular fragments called free radicals damage a wide variety of tissues.

"We definitely found a high level of oxidative stress in the Down syndrome neurons," says Bhattacharyya. "This has been suggested before from other studies, but we were pleased to find more evidence for that. We now have a system we can manipulate to study the effects of oxidative stress and possibly prevent them."

Down syndrome includes a range of symptoms that could result from oxidative stress, Bhattacharyya says, including accelerated aging. "In their 40s, Down syndrome individuals age very quickly. They suddenly get gray hair; their skin wrinkles, there is rapid aging in many organs, and a quick appearance of Alzheimer's disease. Many of these processes may be due to increased oxidative stress, but it remains to be directly tested."

Oxidative stress could be especially significant, because it appears right from the start in the stem cells. "This suggests that these cells go through their whole life with oxidative stress," Bhattacharyya adds, "and that might contribute to the death of neurons later on, or increase susceptibility to Alzheimer's."

Other researchers have created neurons with Down syndrome from induced pluripotent stem cells, Bhattacharyya notes. "However, we are the first to report this synaptic deficit, and to report the effects on genes on other chromosomes in neurons. We are also the first to use stem cells from the same person that either had or lacked the extra chromosome. This allowed us to look at the difference just caused by extra chromosome, not due to the genetic difference among people."

The research, published the week of May 27 in the Proceedings of the National Academy of Sciences, was a basic exploration of the roots of Down syndrome. Bhattacharyya says that while she did not intend to explore treatments in the short term, "we could potentially use these cells to test or intelligently design drugs to target symptoms of Down syndrome."

David Tenenbaum, 608-265-8549, djtenenb@wisc.edu

Anita Bhattacharyya | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Life Sciences:

nachricht New application for acoustics helps estimate marine life populations
16.01.2018 | University of California - San Diego

nachricht Unexpected environmental source of methane discovered
16.01.2018 | University of Washington Health Sciences/UW Medicine

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Gran Chaco: Biodiversity at High Risk

17.01.2018 | Ecology, The Environment and Conservation

Only an atom thick: Physicists succeed in measuring mechanical properties of 2D monolayer materials

17.01.2018 | Physics and Astronomy

Fraunhofer HHI receives AIS Technology Innovation Award 2018 for 3D Human Body Reconstruction

17.01.2018 | Awards Funding

VideoLinks
B2B-VideoLinks
More VideoLinks >>>