Skip to main content

Prion Diseases



Prion is a term used to describe the mysterious infectious agent responsible for several neurodegenerative diseases such as Creutzfeldt-Jakob disease.

The word refers to Dr Stanley Prusiner’s hypothesis of the infectious agent causing these diseases. This hypothesis explains why the infectious agent is resistant to ultraviolet light, which would typically kill the agent by damaging the DNA/RNA, but is instead susceptible to substances that disrupt proteins. 


Prion diseases include Creutzfeldt-Jakob Disease and Kuru in humans, as well as Bovine Spongiform Encephalopathy and Scrapie in animals. They are distinguished by characteristic spongiform changes associated with neuronal loss and failure to induce inflammatory response. 


The prion protein was discovered to be encoded by a gene (PrP gene) found in all animals examined, including humans. The infectious prion protein was caused by a mutation in the PrP gene. These studies argued that prion diseases can be inherited and infectious, which is an unprecedented concept. 


However, there is no chemical difference that distinguishes normal PrP from the disease form. Instead, the only difference between the two proteins was its conformation. The disease form of PrP acts as a template for the refolding of normal PrP into the disease form, resulting in the “spread” of the disease. Prion diseases are thus also diseases of protein conformation. 


For his discovery of prions and his work on the subject, Dr Stanley Prusiner was awarded The Nobel Prize in Physiology of Medicine 1997.


Sources:

https://www.cdc.gov/prions/index.html

https://www.scientificamerican.com/article/what-is-a-prion-specifica/

https://www.hopkinsmedicine.org/health/conditions-and-diseases/prion-diseases

http://www.laskerfoundation.org/awards/show/prions-as-a-cause-of-chronic-neurodegenerative-diseases/

https://www.nobelprize.org/prizes/medicine/1997/prusiner/facts/

Comments

Post a Comment

Popular posts from this blog

Parkinson's Disease

Parkinson’s disease is a progressive nervous system disorder that affects one’s movements. Parkinson’s disease signs and symptoms are different for every individual and may go unnoticed in the early stage. Symptoms typically start on one side of the body and remain worse on that side even after the symptoms begin appearing in both sides of the body.  Generally, the symptoms of Parkinson’s disease include tremors, slowed movement, rigid muscles, impaired posture and balance, loss of automatic movements such as blinking or swinging of arms when walking, and speech and writing changes.  Parkinson’s disease occurs when neurons in an area of the brain that controls movement becomes impaired or dies. These neurons normally produce dopamine. As more neurons become impaired or die, the amount of dopamine produced in the body is reduced significantly, causing the movement problems associated with Parkinson’s disease.  People with Parkinson’s also lose the nerve endings that produc...
Post a Comment
Read more

Tinnitus

Tinnitus is a hearing condition often described as ringing in the ears. Tinnitus can also cause other types of noise in your ears such as: buzzing, roaring, clicking, hissing and humming.  The pitch heard from tinnitus can vary from a high squeal to a low roar, this can affect the patient’s ability to detect tinnitus from external sounds Tinnitus can develop gradually over time or occur suddenly. It is often associated with: age-related hearing loss, inner ear damage, earwax build-up and middle ear infection However, one in every three people with tinnitus doesn't have any obvious problem with their ears or hearing. Sources: https://www.mayoclinic.org/diseases-conditions/tinnitus/diagnosis-treatment/drc-20350162 http://www.webmd.com/a-to-z-guides/understanding-tinnitus-basics
Post a Comment
Read more

Pompe Disease

Pompe disease is a rare genetic condition where the body is unable to break down complex sugars. This is due to a deficiency in an enzyme called acid alfa glucosidase (GAA). Mutations in the GAA gene causes this disorder and results in a build up of glycogen in cells.  Pompe disease can appear in patients from within a few months of birth, at about 1 years old and even during the teenage years.  Those with Pompe disease usually inherit the disease from their parents. However, the allele for the disease is recessive, and may not be expressed in the parents. This disease is typically associated with weak muscles, poor muscle tone and an enlarged liver. However, there are many complications with regards to the respiratory system and motor skills which can also develop.  Enzyme replacement treatment is used for all Pompe patients. A drug called aglucosidase alfa is given intravenously, which acts as a replacement for GAA. Sources: https://my.clevelandclinic.org/health/disease...
Post a Comment
Read more