A prion is thought of as a protein molecule with no genetic material that can infect, multiply and kill. Prions are caused by misfolded ‘normal’ proteins and were “discovered” by Stanley Prusiner (who won a nobel prize).
I recently read Fatal Flaw by Jay Ingram (of Daily Planet and Quirks & Quacks), “the rough and tumble story of prions, filled with rivals, eccentrics, meddlesome governments and brilliant creatives“.
As I sat down with my coffee and danish, I started to read about cannibalism in New Guinea and a disease “Kuru”. How appetizing. This book tracks prion disease from kuru (thought to be caused by cannibalism of prion-diseased brains), scrapie in sheep (spongiform encephalopathy), related to bovine spongiform encephalopathy (mad cow disease), chronic wasting disease in North American deer, and finally to Creutzfeldt-Jakob disease.
The book eventually discusses other diseases that, while not infectious, do involve misfolded proteins; including amyotrophic lateral sclerosis (Lou Gehrig’s), Parkinson’s disease, chronic traumatic encephalopathy (“punch drunk”) and Alzheimer’s disease.
How better understanding prion disease relates to Parkinson’s disease is in the misfolded alpha-synuclein protein deposits that clump together to form lewy bodies. These invading misfolded proteins have a long incubation period (similar to prion disease), where it can be anywhere from 5-30 years before Parkinson’s symptoms even develop. Lewy bodies first accumulate in the nerves of the gut, travel in the spinal cord before spreading to the lower brain (substantia nigra = when symptoms develop) and eventually to cerebral cortex (which may cause dementia). This migration is thought to support the environmental theory of Parkinson’s and paralleled how cow’s who developed Mad Cow Disease ate infected meat and bone meal, which travelled from their stomach to their brain.
Investigation into prions will help Parkinson’s by understanding
1) how midfolded proteins have the ability to move from one cell to another
2) long disease incubation periods
3) possibilities of stabilize proteins to make them resistent to midfolding, which may halt/reverse disease progression.
if you can get past the cannibalism and infected animals (sheep, cows, deer), it really tells the story of how science begins to understand disease, proteins, DNA, outbreaks, and neurodegenerative conditions. much love.