Prions Cause Fatal Neurological Diseases in the Brain of Animals and Humans

Creutzfeldt-Jakob Disease: It happens when a prion protein misfolds itself, thus causing a “domino effect” which unfolds itself causing a malfunction.

Humans have to deal with many different diseases and the ones most disliked are the ones with no cures. Like cancer, transmissible spongiform encephalopathies have no cure, but they are more rare. These diseases are prion diseases which cause the brain to deteriorate. Prions are proteins that sometimes behave like viruses, which mean that they should have some form of nucleic acid, but since they don’t, they cause abnormalities. The nervous system contains many normal prions, but when an abnormal prion comes along, it transforms all the normal prions into abnormal ones. Bovine spongiform encephalopathy is found in cattle, but it can be transmitted to humans.

In bovine spongiform encephalopathy (BSE), the disease is caused by the misfolding of proteins that cause proteins and peptides to develop a fibrillary structure. The PrPc is a correctly folded prion and the misfolded form is called PrPSc. BSE occurs when the normal PrPc come into contact with the toxic PrPSc and the normal prion takes on the shape of the PrPSc. The normal chaperones are unable to convert the PrPSc back to the normal form. The PrPSc now takes on the role of chaperone and the conversion of PrPc prions continue over and over. PrPSc, now being hydrophobic avoids the water of the inner cell and begin to accumulate and form plaques along the neuronal cell membranes. The aggregation of the prions on the cell membrane eventually lead to cell death which produces the sponge-like appearance in the brain of cattle infected with BSE (Thompson, 2014).

This disease gets its name from the German neurologist Hans Gerhard Creutzfeldt and Alfons Maria Jakob that first identified this disease. (Victor, 2015) VCJD is primarily found in the brain of the cattle. Abnormal proteins called prions have thought to be the cause of this disease in both cattle and in humans. These prions cause tiny holes that look like a sponge under a microscope. (Melissa Conrad Stöppler, 2015) Unlike most viruses and bacteria these prions unfortunately do not die when exposed to heat, ultraviolet light, and radiation. Disinfectants that are usually used to kill viruses and bacteria also do not work to kill prions. Even cooking the meat very well will not lower the risk of prions in the

Chronic Wasting Disease (CWD) is a fatal neurodegenerative transmissible spongiform encephalopathy (TSE ) found in some white tailed deer. CWD is associated with diseases such as Mad-Cow disease, Scrapie, and Creutzfeldt–Jakob disease. With well supported evidence it is hypothesized that CWD originated from Scrapie. The causation of CWD is an abnormal form of PrPcwd prion. This prion is a naturally occurring protein found in mammals. Prions lack genome and are highly resistant to degradation. Chronic Wasting Disease can be transmitted by direct contact between the animals and/or on resources such as salt licks.

It is a rare, degenerative but fatal brain disorder affecting very a small fraction of persons. The symptoms usually arise at the age of 60 and the person dies within a year. Many researchers believe that this disorder is the result of an abnormal protein known as prion. About 5-10% cases reported in the United States share a genetic basis where this form of dementia is caused by a mutation in the gene for the prion protein. Patients with Creutzfeldt-Jakob disease suffer from the problems associated with muscle coordination, personality changes, impaired memory, judgment making, thinking disability and impaired vision. Other possible symptoms include insomnia and depression. In later stages the persons

Figure one: A simplistic schematic diagram depicting similarities between the PrPC protein and prion diseases, and the synaptic protein, α-syn and PD. Volpicelli-Daley et al. (2011) and Luk et al. (2012) studies illustrate a neuron-to-neuron transmissibility of α-syn drawing parallels between α-syn and the proteinaceous infectious particle pathogenic prion protein (PrPSc). PrPC consists of roughly 210 amino acids in length. PrPC comprises largely of an α-helical conformation and predominantly resides on the cell surface. When PrPC becomes misfolded, it acquires a high β-sheet content and assembles into rods that coalesce to form amyloid plaques. These aggregations dissipate throughout the brain, aiding neurodegeneration. Importantly, PrPSc is the sole component of the infectious prion and can cause disease in WT animals and humans. α-syn is a protein consisting of roughly 140 amino acids in length. It is a presynaptic protein that is involved in vesicular transport. On binding to cell membranes, α-syn acquires a largely α-helical conformation. When α-syn misfolds, it obtains a high β-sheet content and polymerises into fibrils that are related to the formation of Lewy bodies/neurites. Sole overexpression of α-syn can induce PD in WT animals and humans. There are significant parallels between PrPC involvement in Prion diseases and α-syn role in the formation of PD. This encourages the conception that PD is a “prion-like” disease. A

Addressing the question of nature vs. nurture, Dr. Sonia Mathur states that “Genetics loads the gun, environment pulls the trigger” (Mathur).

Author Beata Sikorska writes a chapter on this disease in the book Neurodegenerative Diseases, she discusses how this rare disease is caused by an abnormal piece of protein (PrP) called a prion (Sikorska, 2012). A prion is an infectious particle made of proteins and the specific protein PrP is the human gene encoding expressed mostly in the nervous system. Proteins are made up by a string of amino acids that fold and form a 3-D shape; the shape the amino acids take gives these proteins it’s function. When a protein does not fold properly it does not function or can become destructive. The human body has specific mechanisms to protect itself from many different types of infections; one of these mechanisms is the blood brain barrier. This barrier blocks harmful substances from entering the brain while allowing necessary nutrients in this includes allowing PrP proteins to enter. Marie-Clare Porter describes the process of CJD in the British Journal of Anesthesia as a prion which is also known as transmissible spongiform encephalopathies, are a group of neurodegenerative conditions that are transmissible, progressive and uniformly fatal (Porter, 2013). Once a prion enters the brain it can infect other normal proteins causing them to lose function and become destructive. As the affected brain cells continue to die they leave tiny sponge-like holes; these holes eventually lead to the signs and symptoms of CJD and are

Generally, a sponge is equated with the soaking or consumption of liquids. Nevertheless, this is not representative of this disease or its effects on the human brain. This progressive and debilitating disease maintains many unknowns, and patient outlook is equivalent to lethal injection. Creutzfeldt-Jakob’s Disease (CJD) is a rare, degenerative, invariably fatal brain disorder, derived from transmissible spongiform encephalopathy caused by prions. Prions occur in a normal state, which are harmless proteins found in the body’s cells, and also in an infectious form that causes disease. Harmless forms of prion proteins have the same sequence of amino acids, but the infectious forms of protein have a different folded shape than normal proteins.

The reason for mad cow disease, or Bovine Spongiform Encephalopathy, is as yet being encountered off. Most powers, in any case, hold that deformed prion proteins cause the illness. These misfolded proteins are irresistible when straightforwardly vaccinated into the mind, infused into the body, or eaten. Since prions need nucleic corrosive, they can't be assaulted the same way infections are. Truth be told, prions are for all intents and purposes

Creutzfedlt-Jakob Disease(CJD) is a rare, non-treatable, and fatal brain disorder caused by a prion, a pathogen that is smaller than a virus. The causative agent of Creutzfedlt-Jakob Disease is very difficult, almost impossible to destory. The casusative agent is a clear watery fluid that fills the space between the arachnoid membrane and the pia mater. Per year, Creutzfedlt-Jakob Disease effects one in every one million people worldwide, in the United States there are around 300 cases. There are 3 catagories of Creutzfedlt-Jakob Disease; The most common being sporadic CJD(the disease appears even though the person has no common risk factors for CJD), Hereditary CJD, and the least common acquired CJD(caused by exposure to the brain or nervous

It has been considered to be one of the most mysterious diseases scientists are fighting so far. With no effective treatment or research on the disease, it has a 100% fatality rate, however fortunately for us, the disease is extremely rare with only 2 cases and deaths since 2008. The disease is caused by an abnormal and infectious protein in the brain called a prion. Normally, prions are used to help transmit messages between certain brain cells. They use “protein folding” which is beginning as a string of amino acids and folding themselves into a 3-D shape. However, CJD causes mistakes in the process, which causes misfolded prion proteins to spread, whereas a healthy person’s body easily recycles them. As more and more misfolded prion

Prions are a type of protein found naturally in the brain and other regions of the central nervous system. The diseases associated with

Prions are an incongruous pathogen that is causative of transmissible spongiform encephalopathies (TSE); a group of fatal neurodegenerative diseases found in mammals. This abnormal proteinaceous particle is believed to be a post-translational mutation of a normal cellular protein found in the brain (Emmanuel, 2002). This naturally occurring pathogen acts similarly to a viral infection, however as it lacks nucleic acid it is invulnerable to death via means of antibiotics or sterilisation. PrPc and PrPsc, the known prion proteins indicative of TSE’s, are known to bind to the surface of neurons and fold these proteins into an abstract spongiform structure. Although the process inducing this folding mechanism is unknown, it is