Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover why not enough choline results in fewer brain cells, poorer memory

18.03.2004


Five years ago, University of North Carolina at Chapel Hill researchers first reported finding that the nutrient choline played a critical role in memory and brain function by positively affecting the brain’s physical development.



Differences in development influenced action, the scientists and their colleagues found. In animal experiments conducted at Duke University, both young and old rats performed significantly better on memory tasks if they received enough choline before birth compared with same-age rats whose mothers were fed choline-deficient diets. The latter showed deficits in the hippocampus and septums of their brains.

Because humans and rodents are so similar biologically, something comparable probably happens in humans, the investigators believe.


Now, working with nerve tissue derived from a human cancer known as a neuroblastoma, the UNC researchers have discovered why more choline causes stem cells -- the parents of brain cells -- to reproduce more than they would if insufficient choline were available.

A report on the findings will appear in the April issue of the Journal of Neurochemistry. Authors are doctoral student Mihai D. Niculescu and Dr. Steven H. Zeisel, professor and chair of nutrition at the UNC schools of public health and medicine. Dr. Yutaka Yamamuro, a former postdoctoral fellow in Zeisel’s laboratory now with Nihon University in Japan, was a key contributor.

"We found that if we provided them with less choline, those nerve cells divided less and multiplied less," Zeisel said. "We then went on to try to explain why by looking at genes known to regulate cell division."

Scientists focused on cyclin-dependent kinase inhibitor 3 genes, which keep cells from dividing until a biochemical message turns the genes off, he said. They found exactly what they expected.

"We showed that choline donates a piece of its molecule called a methyl group and that gets put on the DNA for those genes," Zeisel said. "When the gene is methylated, its expression is shut down."

But when the gene is under-methylated -- such as when there’s not enough choline in the diet -- then it’s turned on -- halting or slowing nerve cell division, he said.

"Nature has built a remarkable switch into these genes something like the switches we have on the walls at home and at work," Zeisel said. "In this very complicated study, we’ve discovered that the diet during pregnancy turns on or turns off division of stem cells that form the memory areas of the brain. Once you have changed formation of the memory areas, we can see it later in how the babies perform on memory testing once they are born. And the deficits can last a lifetime."

The next step, Zeisel said, will be confirm that the same things happen in living mouse fetuses when the mothers receive either high or low doses of choline.

Developing babies get choline from their mothers during pregnancy and from breast milk after they are born, he said. Other foods rich in choline include eggs, meat, peanuts and dietary supplements. Breast milk contains much more of this nutrient than many infant formulas.

Pregnancy and nursing make female rats -- and presumably women -- especially susceptible to becoming choline deficient, the scientist said. The months before and immediately after childbirth appear to be special times when women need more in their diets.

Choline is a vitamin-like substance that is sometimes treated like B vitamins and folic acid in dietary recommendations. The body uses it in making the nerve messenger chemical known as acetylcholine and in building cell membrane -- the biological "wrapper" that keeps cells from leaking.

A paper Zeisel’s laboratory published in January in the Journal of Nutrition also showed that the nutrient folic acid is not just critical for brain development in embryos during the earliest stages of pregnancy, but it’s a key to healthy brain growth and function late in pregnancy too.

Humans and other mammals lacking sufficient folic acid shortly before they are born can suffer lifelong brain impairment, the earlier UNC animal studies indicated. Such research can never be done directly in growing human fetuses for obvious reasons.

"In the past few years, folic acid has been the single greatest success story in nutrition and in preventing birth defects," Zeisel said. "Spina bifida, the early birth defect in which the spinal cord doesn’t close, and anencephaly, a condition in which the brain doesn’t form normally, can be eliminated between 50 and 85 percent of the time if women get sufficient folic acid before they become pregnant."

The National Institute on Aging supports the continuing studies at UNC, which maintains a federally designated and National Institutes of Health-supported Clinical Nutrition Research Unit. The U.S. Department of Agriculture recently released a choline food database Zeisel helped develop: www.nal.usda.gov/fnic/foodcomp.

David Williamson | UNC
Further information:
http://www.unc.edu/news/newsserv/archives/mar04/zeisel031804.html
http://www.nal.usda.gov/fnic/foodcomp

More articles from Life Sciences:

nachricht For a chimpanzee, one good turn deserves another
27.06.2017 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)

nachricht New method to rapidly map the 'social networks' of proteins
27.06.2017 | Salk Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>