Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In vitro study suggests acrylamide causes DNA damage

18.06.2003


Acrylamide, a possible human carcinogen that has been found in a variety of fried and starch-based foods, appears to exert its mutagenicity (the capacity to induce mutations) by forming DNA adducts and introducing genetic mutations, according to a study in the June 18 issue of the Journal of the National Cancer Institute. DNA adducts can interfere with the DNA replication process and lead to mutations and, in theory, to tumor formation.



Exposure to acrylamide has been shown to increase the incidence of a variety of cancers in rats and mice. Although no one knows how this process works, one theory is that acrylamide triggers mutagenesis by damaging DNA.

Ahmad Besaratinia, Ph.D., and Gerd P. Pfeifer, Ph.D., of the Beckman Research Institute of the City of Hope National Medical Center in Duarte, Calif., tested this hypothesis in mammalian cells in vitro by exposing mouse embryonic fibroblasts (connective tissue cells) that carried an artificially inserted gene known as a transgene to either acrylamide or a control, double-distilled water.


Cells treated with acrylamide had more DNA adduct formation at specific spots along the transgene than control-treated cells. Treatment of the cells with low (micromolar) concentrations of acrylamide was associated with a twofold increase in the number of mutations in the transgene compared with the control-treated cells. This mutation rate was similar to that of cells treated with the known carcinogen BPDE at considerably lower concentrations. However, treatment of the cells with higher concentrations of acrylamide (e.g., in the millimolar range) resulted in a mutation rate similar to that of untreated cells, possibly because cells die when exposed to such high concentrations of acrylamide.

The researchers also found that acrylamide exposure resulted in the formation of a spectrum of genetic mutations that were different from those mutations formed spontaneously. They point out, however, that the sites of acrylamide-induced DNA adducts did not match the pattern of acrylamide-induced mutations, suggesting that not all DNA adducts formed by acrylamide resulted in mutations.

The researchers note that the role of acrylamide in embryonic mouse fibroblasts may differ from its role in a grown animal. They acknowledge that their study was conducted on a transgene rather than a native gene and say that their findings cannot yet be applied to humans.

In an accompanying editorial, Fredrik Granath, Ph.D., of the Karolinska Institute in Stockholm, Sweden, and Margareta Törnqvist, Ph.D., of Stockholm University in Sweden, point out that the estimated average concentration of acrylamide in the blood is approximately 6 nanomolar, a concentration that is five times lower than the lowest concentration used in this study. "Studying effects at such low exposures is very difficult even in in vitro studies," they say. Considering the low statistical power in epidemiologic studies, they say that "clarification and improvement of the risk assessment of acrylamide will be obtained primarily from experimental studies."

They say that the estimated individual cancer risk from dietary acrylamide is quite small and they would not recommend changing nutritional guidelines. "However, the situation for vulnerable groups, e.g., pregnant women and children, should always be carefully considered," they write.


Contact: Greg Hughes, City of Hope National Medical Center, 626-359-8111 Ext. 65263; fax: 626-301-8462, ghughes@coh.org.

Editorial: Margareta Törnqvist, Stockholm University 46-8163-769, 46-703-736771 (cell), margareta.tornqvist@mk.su.se or Fredrik Granath (after June 18), Karolinska Institute, 46-8517-79182, fredrik.granath@mep.ki.se.

Besaratinia A, Pfeifer GP. Weak yet distinct mutagenicity of acrylamide in mammalian cells. J Natl Cancer Inst 2003;95:889–96.

Editorial: Granath F, Törnqvist M. Who knows whether acrylamide in food is hazardous to humans? J Natl Cancer Inst 2003;95:842–3.

Note: The Journal of the National Cancer Institute is published by Oxford University Press and is not affiliated with the National Cancer Institute. Attribution to the Journal of the National Cancer Institute is requested in all news coverage.

Linda Wang | EurekAlert!
Further information:
http://jncicancerspectrum.oupjournals.org/

More articles from Health and Medicine:

nachricht Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center

nachricht Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>