Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study finds chlorophyll can help prevent cancer - but questions traditional research methods

13.01.2012
A recent study at Oregon State University found that the chlorophyll in green vegetables offers protection against cancer when tested against the modest carcinogen exposure levels most likely to be found in the environment.

However, chlorophyll actually increases the number of tumors at very high carcinogen exposure levels.

Beyond confirming the value of chlorophyll, the research raises serious questions about whether traditional lab studies done with mice and high levels of toxic exposure are providing accurate answers to what is a real health risk, what isn’t, and what dietary or pharmaceutical approaches are useful.

The findings, published in the journal Food and Chemical Toxicology, were done using 12,360 rainbow trout as laboratory models, instead of more common laboratory mice. Rodent studies are much more expensive, forcing the use of fewer specimens and higher carcinogen exposures.

“There’s considerable evidence in epidemiologic and other clinical studies with humans that chlorophyll and its derivative, chlorophyllin, can protect against cancer,” said Tammie McQuistan, a research assistant working with George Bailey, a professor emeritus in the Linus Pauling Institute at OSU.

“This study, like others before it, found that chlorophyll can reduce tumors, up to a point,” McQuistan said. “But at very high doses of the same carcinogen, chlorophyll actually made the problem worse. This questions the value of an approach often used in studying cancer-causing compounds.”

OSU experts in recent years have become pioneers in the use of rainbow trout as a model for biomedical research, in part because the fish react in similar ways to those of rodents, but also because scientists can use thousands of them – instead of dozens or hundreds of mice – and do experiments that would not otherwise be possible.

In that context, this study raises questions about a fundamental premise of much medical research – expose a laboratory animal to a compound at high levels, observe the result, and predict that a proportional amount of that same result would be present at low levels of exposure.

In one part of the study, trout were exposed to fairly moderate levels of a known carcinogen, but also given chlorophyll. This reduced their number of liver tumors by 29-64 percent, and stomach tumors by 24-45 percent. But in another part of the study, using much higher and unrealistic doses of the same carcinogen, the use of chlorophyll caused a significant increase in the number of tumors.

In other words, traditional research with small numbers of animals fed very high doses of a carcinogen might conclude that chlorophyll has the potential to increase human cancer risk. This study, and other evidence and trials, concludes just the opposite.

It also found that the protective mechanism of chlorophyll is fairly simple – it just binds with and sequesters carcinogens within the gastrointestinal tract until they are eliminated from the body. At the lower carcinogen doses and cancer rates relevant to humans, chlorophyll was strongly protective.

“The central assumption of such experiments is that intervention effects at high carcinogen dose will apply equally at lower carcinogen doses,” the researchers wrote in their report. “Contrary to the usual assumption, the outcomes in the major target organ were strikingly dependent on carcinogen dose.”

OSU experts have argued that in some studies rainbow trout can produce better, more accurate, real-world results compared to traditional rodent animal models and relevant to humans, because many more specimens can be used and lower doses of toxins studied. Experiments done with fish may be about 20 times cheaper and, in the end, more scientifically valid, they say.

“Results derived at high carcinogen doses and high tumor responses may be irrelevant for human intervention,” the scientists said in their conclusion.

This work was supported by the National Institutes of Health.

About the Linus Pauling Institute: The Linus Pauling Institute at OSU is a world leader in the study of micronutrients and their role in promoting optimum health or preventing and treating disease. Major areas of research include heart disease, cancer, aging and neurodegenerative disease.

George Bailey | EurekAlert!
Further information:
http://oregonstate.edu

More articles from Studies and Analyses:

nachricht New model connects respiratory droplet physics with spread of Covid-19
21.07.2020 | University of California - San Diego

nachricht Risk of infection with COVID-19 from singing: First results of aerosol study with the Bavarian Radio Chorus
03.07.2020 | Klinikum der Universität München

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

Im Focus: NYUAD astrophysicist investigates the possibility of life below the surface of Mars

  • A rover expected to explore below the surface of Mars in 2022 has the potential to provide more insights
  • The findings published in Scientific Reports, Springer Nature suggests the presence of traces of water on Mars, raising the question of the possibility of a life-supporting environment

Although no life has been detected on the Martian surface, a new study from astrophysicist and research scientist at the Center for Space Science at NYU Abu...

Im Focus: Manipulating non-magnetic atoms in a chromium halide enables tuning of magnetic properties

New approach creates synthetic layered magnets with unprecedented level of control over their magnetic properties

The magnetic properties of a chromium halide can be tuned by manipulating the non-magnetic atoms in the material, a team, led by Boston College researchers,...

Im Focus: A new method to significantly increase the range and stability of optical tweezers

Scientists of Tomsk Polytechnic University jointly with a team of the V.E. Zuev Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences have discovered a method to increase the operation range of optical traps also known

Optical tweezers are a device which uses a laser beam to move micron-sized objects such as living cells, proteins, and molecules. In 2018, the American...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Novel approach improves graphene-based supercapacitors

03.08.2020 | Information Technology

Germany-wide rainfall measurements by utilizing the mobile network

03.08.2020 | Information Technology

Drug discovery: First rational strategy to find molecular glue degraders

03.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>