Magnetic fields may hold key to malaria treatment, UW researchers find

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http://www.washington.edu/newsroom/news/2000archive/03-00archive/k033000.html

 

DATE: March 30, 2000

 

 

Magnetic fields may hold key to malaria treatment, UW researchers find

 

 

A malaria parasite within a human red blood cell. The large circle

in the parasite is a food vacuole. Stacked heme are visible inside the

vacuole.

 

Researchers at the University of Washington have discovered a method

of treating malaria with magnetic fields that could prove

revolutionary in controlling the disease the World Health Organization

calls one of the world's most complex and serious human health concerns.

 

Henry Lai, UW research professor of bioengineering, says the malaria

parasite Plasmodium appears to lose vigor and can die when exposed to

oscillating magnetic fields, which Lai thinks may cause tiny

iron-containing particles inside the parasite to move in ways that

damage the organism.

 

" If further studies confirm our findings and their application in

animals and people, this would be an inexpensive and simple way to

treat a disease that affects 500 million people every year, almost all

in third-world countries, " Lai said. According to the World Health

Organization, as many as 2.7 million people die of malaria every year.

Approximately 1 million of those are children.

 

In the past two decades, the emergence of drug-resistant malaria

parasites has created enormous problems in controlling the disease.

Lai says his method could bypass those concerns because it is unlikely

Plasmodium could develop a resistance to magnetic fields.

 

Malaria is spread by female Anopheles mosquitoes. The organism first

invades the liver, then re-emerges into the bloodstream and attacks

red blood cells. This is what causes malaria's hallmark symptoms:

fever, uncontrolled shivering, aches in the joints and headaches.

Infected blood cells can block blood vessels to the brain, causing

seizures and death. Other vital organs are also at risk.

 

Lai's research appears to take advantage of how the parasites feed.

Malaria parasites " eat " the hemoglobin in red blood cells of the host.

They break down the globin portion of the hemoglobin molecule, but the

iron portion, or the heme, is left intact because the parasite lacks

the enzyme needed to degrade it. This causes a problem for the

parasite because free heme molecules can cause a chain reaction of

oxidation of unsaturated fatty acids, leading to membrane damage in

the parasite. The malaria organism renders the free heme molecules

non-toxic by binding them into long stacks - like " tiny bar magnets, "

according to Lai.

 

He and three other researchers have exposed Plasmodium falciparum, the

deadliest of the four malaria parasite species, to a weak alternating,

or oscillating, magnetic field. Data sets showed that exposed samples

ended up with 33 to 70 percent fewer parasites than unexposed samples.

Measurements of hypoxanthine, a precursor for nucleic acid synthesis

used by the parasite, indicated that metabolic activities had also

significantly slowed in exposed samples. Such reductions would be

enough to manage malaria, Lai said.

 

The oscillating magnetic field may affect the parasites in two ways,

according to Lai. In organisms still in the process of binding free

heme molecules into stacks, the alternating field likely " shakes " the

stacked heme molecules, preventing further stacking. That would allow

harmful heme free reign within the parasite. If the parasite is

further along in its life cycle and has already bound the heme into

stacks, the oscillating field could cause the stacks to spin, causing

damage and death of the parasite.

 

Although initially promising, Lai says more research is needed.

 

" We need to make certain that it won't harm the host, " Lai said. " My

guess is that it won't. It's a very weak magnetic field, just a little

stronger than the earth's. The difference is that it is oscillating. "

 

If the method is proven effective and safe, Lai envisions rooms

equipped with magnetic coils to produce the oscillating field.

 

" It would be very easy. People could come to the room and sit and read

or whatever while they're being treated, " he said. " Or you could set

it up in the back of a big transport truck, then drive from village to

village to treat people. "

 

Collaborating researchers include Jean E. Feagin, UW associate

professor of pathobiology and senior scientist at the Seattle

Biomedical Research Institute; and Ceon Ramon, UW electrical

engineering research scientist.

 

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For more information, contact Lai at (206) 543-1071 or

hlai. Copies of a background symposium paper on the

research are available via fax from Rob Harrill at (206) 543-2580 or

rharrill. A high-resolution image of the malaria

parasite is available on the Web at:

http://www.washington.edu/newsroom/news/images/malariacell.jpg.