Alzheimer's Disease a Prion?

You may be wondering what a prion is and whyfound that fit this pattern. These included scrapie
you should care. Well, your ears might perk up a(found in sheep), chronic wasting disease (found in
lot if you hear the words - 'Mad Cow Disease'.deer and elk), Creutzfeldt-Jakob disease and fatal
That disease is caused by a transmissible prion.familial insomnia in humans, and bovine spongiform
Prion related diseases have been recognized forencephalopathy in cattle (also known as mad cow
years. However, until recently we did not realizedisease).
what caused them.What is not known is if there is a connection to
What we did know about them is that theyprion disease and Alzheimer's disease. We have
caused dementia. People gradually lost their abilityrecognized several genetic mutations that can
to reason and remember things. We also noticedcause Alzheimer's disease and form prions in the
that there were typical changes in the brain whenbody of the person with the mutation. However,
looked at during autopsy.this does not account for the total number of
Prions became famous when Kuru was foundthose with Alzheimer's disease.
among the Fore people of New Guinea. In thisOne piece of evidence that is suspicious. It is
disease, people would get unsteady gait, tremors,known that people who habitually eat meat more
and slurred speech. The interesting thing was thatthan four times a week have three times as
only women and children seemed to get themuch chance of getting Alzheimer's disease than
disease.vegetarians. However, at least some of this
It was finally noticed that when a person died, hisstatistic could be related to increasing
family would eat him as a way to honor the dead.arteriosclerosis (hardening of the arteries) in those
But only the women and children participated inthat eat meat.
this practice. Scientists found that by stopping thisIf there is a prion that causes Alzheimer's disease
practice, the incidence of the disease suddenlythat you can get from eating meat, why can't
plummeted.you easily prove or disprove it? Well, here is the
Further research in Kuru found that the causeproblem. The currently know prions cause disease
was a protein - not a bacteria or virus.fast enough that you can put the prions into lab
Furthermore, there was no way to destroy thisanimals like white mice and they get the disease.
protein by filtering or cooking. Proteins are formedHowever, have you ever seen a mouse live as
as a long molecule that then folds over and over.long as someone who has Alzheimer's disease? Of
The shape of the folded molecule determinescourse not.
how it functions.We do know that prions come in strains that
It also determines what enzymes in the body arevary widely in the amount of time that it takes
needed to break it down when it is no longerto cause the disease. So, here is the big question.
needed. The prion works by causing a protein inWhat if there were a prion that caused disease in
the brain into the wrong shape. Therefore it doeshumans, but it took longer to cause problems
not work and the brain makes more and more ofthan the lifespan of the animal that it came from?
the chemical - trying to make enough of theFor instance, if cows live 10 years but it takes 50
protein to fill the need of the body.years for the disease to show up, you would
The real devastation of the disease though is thatnever - ever see the disease in cows even if
the resulting misshapen chemical does not havethey carried the disease. The same goes for
enzymes in the body that can break it down! Sochickens, sheep and pigs. You see the problem?
the protein builds up in large amounts thatAt this point, we do know that one fact - that
become toxic to brain cells and finally cause themyou get only 1/3 as much dementia if you are a
to die.vegetarian. Until more is known about what is
Once scientists realized the cause and effect ofreally in fact safe to eat, vegetarians have a leg
this prion, several other known diseases wereup on carnivores on this issue.